Sibanye Stillwater Ltd 20-F/A, filed Dec 14, 2023
Sibanye Stillwater Ltd (SBSW)
20-F/A
2023-12-14
For: 2022-12-31
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Added on
August 22, 2026
About this 20-F/A
Sibanye Stillwater Ltd filed this 20-F/A on December 14, 2023, covering the fiscal year ended December 31, 2022.
As filed with the Securities and Exchange Commission on 14 December 2023 | ||
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
Form (Amendment No. 1) | |||||||||||||||||||||||||||||
(Mark One) or For the fiscal year ended or or Date of event requiring this shell company report For the transition period from to Commission file number: | |||||||||||||||||||||||||||||
(Exact name of registrant as specified in its charter) | |||||||||||||||||||||||||||||
(Jurisdiction of incorporation or organization)
011-27-11-278-9600
(Address of principal executive offices)
with copies to:
Chief Financial Officer
Sibanye Stillwater Limited
Tel:
Jeffrey Cohen
Igor Rogovoy
Linklaters LLP
Tel: 011-44-20-7456-3660
One Silk Street
London EC2Y 8HQ
United Kingdom
Linklaters LLP
Tel: 011-44-20-7456-3660
One Silk Street
London EC2Y 8HQ
United Kingdom
(Name, Telephone, E-mail and/or Facsimile number and Address of Company Contact Person)
Securities registered or to be registered pursuant to Section 12(b) of the Act
| Title of Each Class | Trading Symbol | Name of Each Exchange on Which Registered | ||||||||||||||||||||||||||||||
| * Not for trading, but only in connection with the registration of the American Depositary Shares pursuant to the requirements of the Securities and Exchange Commission. | ||||||||||||||||||||||||||||||||
Securities registered or to be registered pursuant to Section 12(g) of the Act None (Title of Class) Securities for which there is a reporting obligation pursuant to Section 15(d) of the Act None (Title of Class) Indicate the number of outstanding shares of each of the issuer’s classes of capital or common stock as of the close of the period covered by the Annual Report | ||||||||||||||||||||||||||||||||
If this report is an annual or transition report, indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934. Yes ☐ No ☒
Note – Checking the box above will not relieve any registrant required to file reports pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 from their obligations under those Sections.
Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐
Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No ☐
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or an emerging growth company. See definition of “large accelerated filer,” “accelerated filer,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.
If an emerging growth company that prepares its financial statements in accordance with U.S. GAAP, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards† provided pursuant to Section 13(a) of the Exchange Act. ☐
† The term “new or revised financial accounting standard” refers to any update issued by the Financial Accounting Standards Board to its Accounting Standards Codification after April 5, 2012.
Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report. ☒
If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements. ☐
Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b). ☐.
Indicate by check mark which basis of accounting the registrant has used to prepare the financial statements included in this filing:
U.S. GAAP ☐ International Financial Reporting Standards as issued by the International Accounting Standards Board ☒ Other ☐
If “Other” has been checked in response to the previous question, indicate by check mark which financial statement item the registrant has elected to follow: Item 17 ☐ Item 18 ☐
If this is an annual report, indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒
Auditor name: Ernst & Young Incorporated Auditor location: Johannesburg, Republic of South Africa Auditor Firm ID: 1698
(APPLICABLE ONLY TO ISSUERS INVOLVED IN BANKRUPTCY PROCEEDINGS DURING THE PAST FIVE YEARS)
Indicate by check mark whether the registrant has filed all documents and reports required to be filed by Sections 12, 13 or 15(d) of the Securities Exchange Act of 1934 subsequent to the distribution of securities under a plan confirmed by a court. Yes ☐ No ☐
EXPLANATORY NOTE
Sibanye Stillwater Limited (the “Company”) is filing this Amendment No. 1 (the “Amendment No. 1”) to the Annual Report on Form 20-F for the fiscal year ended 31 December 2022 filed with the Securities and Exchange Commission (the “Commission”) on 24 April 2023 (the "2022 Form 20-F"), solely for the purpose of amending exhibits 96.1 “Technical Report Summary of the Sibanye-Stillwater US PGM Operations (Stillwater and East Boulder)” and 96.7 “Technical Report Summary of Keliber lithium project” thereto, to reflect comments received from the staff of the Commission.
In connection with the filing of this Amendment No. 1, the Company is including the relevant certifications of the Company’s Chief Executive Officer and Chief Financial Officer pursuant to Rule 13a-14(a) and Rule 15d-14(a) (the “Section 302 Certifications”) of the Securities Exchange Act of 1934 (the “Exchange Act”). The Company is not including certifications pursuant to Section 1350 of Chapter 63 of Title 18 of the United States Code (18 U.S.C.1350) in this Amendment No. 1 as no financial statements are being filed.
Other than as expressly set forth above, this Amendment No. 1 does not, and does not purport to, amend, update or restate any other information in the 2022 Form 20-F as originally filed, or reflect any events that have occurred since the 2022 Form 20-F was filed on 24 April 2023.
EXHIBITS
The following documents are included as Exhibits to this Amendment No. 1.
| No. | Exhibit | |||||||
1.1** | ||||||||
2.1** | ||||||||
2.2** | ||||||||
2.3** | ||||||||
2.4** | ||||||||
4.1** | ||||||||
4.2** | ||||||||
4.3** | ||||||||
4.4** | ||||||||
8.1** | ||||||||
12.1* | ||||||||
12.2* | ||||||||
15.1** | ||||||||
16** | ||||||||
96.1* | ||||||||
96.2** | ||||||||
96.3** | ||||||||
96.4** | ||||||||
96.5** | ||||||||
96.6** | ||||||||
96.7* | ||||||||
| 101* | Interactive data files | |||||||
* Filed herewith
** Previously filed
SIGNATURES
The registrant hereby certifies that it meets all of the requirements for filing on Form 20-F and that it has duly caused and authorised the undersigned to sign this Amendment No 1 to the Annual Report for the fiscal year ended 31 December 2022 on its behalf.
| SIBANYE STILLWATER LIMITED | |||||||||||
| /s/ Charl Keyter | |||||||||||
| Name: | Charl Keyter | ||||||||||
| Title: | Chief Financial Officer | ||||||||||
| Date: | 14 December 2023 | ||||||||||
Exhibit 12.1
CERTIFICATIONS
I, Neal Froneman, the Chief Executive Officer of Sibanye Stillwater Limited, certify that:
1.I have reviewed this Amendment No.1 to the annual report on Form 20-F of Sibanye Stillwater Limited for the fiscal year ended 31 December 2022;
2.Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;
3.[Omitted];
4.[Omitted];
5.[Omitted].
Date: 14 December 2023
/s/ Neal Froneman | |||||||||||||||||
Neal Froneman | |||||||||||||||||
Chief Executive Officer | |||||||||||||||||
Exhibit 12.2
CERTIFICATIONS
I, Charl Keyter, the Chief Financial Officer of Sibanye Stillwater Limited, certify that:
1.I have reviewed this Amendment No.1 to the annual report on Form 20-F of Sibanye Stillwater Limited for the fiscal year ended 31 December 2022;
2.Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;
3.[Omitted];
4.[Omitted];
5.[Omitted].
Date: 14 December 2023
/s/ Charl Keyter | |||||||||||||||||
Charl Keyter | |||||||||||||||||
Chief Financial Officer | |||||||||||||||||
TECHNICAL REPORT SUMMARY OF THE SIBANYE-STILLWATER US PGM OPERATIONS SITUATED IN THE MONTANA, UNITED STATES Report Date: 13 December 2023 Effective Date: 31 December 2021 Prepared by: Qualified Persons at Sibanye-Stillwater US PGM Operations ii Important Notices Description of Amendments to Previously Filed Technical Report Summary This Technical Report Summary (TRS) for the US PGM Operations of Sibanye-Stillwater Limited (Sibanye- Stillwater) (the Sibanye-Stillwater US PGM Operations), dated 13 December 2023, serves as an amendment to the TRS prepared by the Qualified Persons at Sibanye-Stillwater for the fiscal year ended 31 December 2021, effective 31 December 2021, which was filed as Exhibit 96.1 to Sibanye- Stillwater’s 2021 annual report filed on Form 20-F on 22 April 2022 (the Original 2021 Sibanye-Stillwater US PGM Operations TRS) and incorporated by reference into Sibanye-Stillwater’s 2022 annual report filed on Form 20-F on 24 April 2023. This TRS was prepared by the Qualified Persons at Sibanye-Stillwater following the receipt of comment letters by Sibanye-Stillwater and associated dialogue with the staff (the Staff) of the United States Securities and Exchange Commission (the SEC) regarding information in the Original 2021 Sibanye- Stillwater US PGM Operations TRS. While this TRS incorporates certain changes to the Original 2021 Sibanye-Stillwater US PGM Operations TRS, it maintains an effective date of 31 December 2021 with regard to assumptions and the knowledge of the Qualified Persons at Sibanye-Stillwater. This TRS revises the following information in the Original 2021 Sibanye-Stillwater US PGM Operations TRS as a result of the comments received from the Staff: • Revisions to the abridged cash flow results table on page [253] (Table 63) to include the particularized disclosure requirements of Item 601(b)(96)(iii)(B)(19) of Regulation S-K in one table, including annual production for the life of the project and the associated revenue, operating and capital costs, taxes, and royalties. iii Table of Contents EXECUTIVE SUMMARY ............................................................................................................................. 1 Introduction ............................................................................................................................................ 1 Property Description, Mineral Rights and Ownership ........................................................................ 1 Geology and Mineralisation ................................................................................................................. 2 Exploration Status, Development and Operations and Mineral Resource Estimates.................... 2 Mining Methods, Ore Processing, Infrastructure and Mineral Reserve Estimates ........................... 4 Capital and Operating Cost Estimates and Economic Analysis ...................................................... 7 Permitting Requirements ....................................................................................................................... 8 Conclusions and Recommendations .................................................................................................. 8 INTRODUCTION ....................................................................................................................................... 9 Registrant ................................................................................................................................................ 9 Compliance ............................................................................................................................................ 9 Terms of Reference and Purpose of the Technical Report ............................................................... 9 Sources of Information......................................................................................................................... 10 Site Inspection by Qualified Persons .................................................................................................. 11 Units, Currencies and Survey Coordinate System ............................................................................ 11 RELIANCE ON INFORMATION PROVIDED BY REGISTRANT ................................................................. 12 PROPERTY DESCRIPTION ....................................................................................................................... 14 Location and Operations Overview .................................................................................................. 14 Mineral Title ........................................................................................................................................... 15 Title Overview ................................................................................................................................ 15 Title and Tenure Held ................................................................................................................... 15 Title and Tenure Conditions and Compliance .......................................................................... 17 Surface Rights and Servitudes..................................................................................................... 18 Royalties ................................................................................................................................................ 20 Legal Proceedings and Significant Encumbrances to the Property ............................................. 20 ACCESSIBILITY, CLIMATE, LOCAL RESOURCES, INFRASTRUCTURE AND PHYSIOGRAPHY ................ 22 Topography and Elevation ................................................................................................................. 22 Stillwater Mine and the Hertzler Tailing Storage Facility ........................................................... 22 East Boulder Mine ......................................................................................................................... 22 Fauna and Flora ........................................................................................................................... 22 Access, Towns and Regional Infrastructure ...................................................................................... 23 Climate .................................................................................................................................................. 23 Infrastructure and Bulk Service Supplies ............................................................................................ 24 iv Personnel Sources ................................................................................................................................ 25 HISTORY ................................................................................................................................................. 26 Ownership History ................................................................................................................................. 26 Previous Exploration and Mine Development .................................................................................. 27 Previous Exploration ..................................................................................................................... 27 Mine Development ...................................................................................................................... 28 Plant, Property and Equipment .......................................................................................................... 29 ADJACENT PROPERTIES ......................................................................................................................... 31 GEOLOGICAL SETTING, MINERALISATION AND DEPOSIT .................................................................. 32 Regional Geology ................................................................................................................................ 32 Local and Property Geology .............................................................................................................. 35 Local Stratigraphy ........................................................................................................................ 35 J-M Reef Mineralisation ................................................................................................................ 37 EXPLORATION ........................................................................................................................................ 44 Data Acquisition Overview ................................................................................................................. 44 Gravity Surveys ..................................................................................................................................... 44 Aeromagnetic Surveys ........................................................................................................................ 44 Topographic Surveys ........................................................................................................................... 45 Exploration and Mineral Resource Evaluation Drilling ..................................................................... 45 Drilling ............................................................................................................................................. 45 Core Logging and Reef Delineation .......................................................................................... 50 Survey Data .......................................................................................................................................... 50 Density Determination ......................................................................................................................... 52 Underground Mapping ....................................................................................................................... 52 Hydrogeological Drilling and Testwork .............................................................................................. 53 Stillwater Mine ............................................................................................................................... 53 East Boulder Mine ......................................................................................................................... 56 Geotechnical Data, Testing and Analysis ......................................................................................... 58 Geotechnical Characterisation ................................................................................................. 58 Geotechnical Testwork and Data Collection ........................................................................... 58 Geotechnical Results and Interpretation .................................................................................. 60 SAMPLE PREPARATION, ANALYSES AND SECURITY ............................................................................ 62 Sampling Governance and Quality Assurance ............................................................................... 62 Reef Sampling ...................................................................................................................................... 63 Sample Preparation and Analysis ...................................................................................................... 63 Laboratory ..................................................................................................................................... 63
v Sample Preparation and Analysis .............................................................................................. 64 Analytical Quality Control ................................................................................................................... 65 Nature and Extent of Quality Control Procedures ................................................................... 65 Quality Control Results ................................................................................................................. 66 DATA VERIFICATION ............................................................................................................................. 71 Data Storage and Database Management .................................................................................... 71 Database Verification ......................................................................................................................... 71 MINERAL PROCESSING AND METALLURGICAL TESTING .................................................................... 73 Metallurgical Testwork and Amenability ........................................................................................... 73 Deleterious Elements............................................................................................................................ 73 MINERAL RESOURCE ESTIMATES ........................................................................................................... 74 Background .......................................................................................................................................... 74 Geological Modelling and Interpretation ......................................................................................... 74 Zone Picking and Evaluation Cut Determination ..................................................................... 74 Data Processing and Analysis ..................................................................................................... 75 Structural Modelling and Geological Loss Determination ...................................................... 81 Geological Interpretation and Wireframe Modelling .............................................................. 81 Block Modelling ............................................................................................................................ 86 Grade and Tonnage Estimation ......................................................................................................... 86 Grade and Thickness Estimation................................................................................................. 86 Block Model Validation ............................................................................................................... 90 Tonnage Estimation ...................................................................................................................... 92 Mineral Resource Classification.......................................................................................................... 92 Cut-off Grades, Technical Factors and Reasonable Prospects for Economic Extraction .......... 93 Prospects for Eventual Economic Extraction Assessment ....................................................... 93 Cut-off Grades and Minimum Mining Width ............................................................................. 94 Mineral Resource Estimates ................................................................................................................ 96 MINERAL RESERVE ESTIMATES ............................................................................................................... 98 Mineral Resource to Mine Reserve Conversion Methodology ....................................................... 98 Mineral Resources Available for Conversion ............................................................................ 98 Mineral Reserve Estimation Methodology ................................................................................. 98 Point of Reference ..................................................................................................................... 100 Cut-off Grades ............................................................................................................................ 100 Mineral Reserve Classification Criteria ............................................................................................ 101 Mineral Reserve Estimates ................................................................................................................. 104 Risk Assessments ................................................................................................................................. 105 vi MINING METHODS .............................................................................................................................. 107 Introduction ........................................................................................................................................ 107 Mine Design ........................................................................................................................................ 107 Mining Method Rationale .......................................................................................................... 107 Ramp and Fill Method ............................................................................................................... 108 Captive Cut and Fill Method .................................................................................................... 109 Sub-level Extraction and Sub-level Development.................................................................. 109 Transverse Long Hole Stoping ................................................................................................... 110 Stope Extraction Ratios .............................................................................................................. 111 Hydrogeological Model .................................................................................................................... 111 Stillwater Mine ............................................................................................................................. 111 East Boulder Mine ....................................................................................................................... 112 Geotechnical Model ......................................................................................................................... 112 Geotechnical Characterisation ............................................................................................... 112 Support Design ........................................................................................................................... 113 Surface and Subsidence Control ............................................................................................. 114 Backfill .......................................................................................................................................... 114 Stillwater Mine Operations ................................................................................................................ 115 Background ................................................................................................................................ 115 Key Operational Infrastructure ................................................................................................. 116 Mine Layout ................................................................................................................................ 116 East Boulder Mine Operations .......................................................................................................... 117 Background ................................................................................................................................ 117 Key Operational Infrastructure ................................................................................................. 117 Mine Layout ................................................................................................................................ 118 Life of Mine Planning and Budgeting .............................................................................................. 120 Introduction ................................................................................................................................. 120 Mine Planning Criteria ................................................................................................................ 120 Modifying Factors ....................................................................................................................... 122 Indicated Mineral Resources to Probable Mineral Reserves Conversion Factors .............. 124 Life of Mine Production Scheduling and Budgeting ...................................................................... 125 Process Overview ....................................................................................................................... 125 LoM Production Schedule for Stillwater Mine ......................................................................... 126 Life of Mine Production Schedule for East Boulder Mine ....................................................... 128 Mining Equipment .............................................................................................................................. 129 Stillwater Mine ............................................................................................................................. 129 East Boulder Mine ....................................................................................................................... 130 Logistics ............................................................................................................................................... 131 Stillwater Mine ............................................................................................................................. 131 East Boulder Mine ....................................................................................................................... 132 Underground Mine Services .............................................................................................................. 133 Stillwater Mine ............................................................................................................................. 133 vii East Boulder Mine ....................................................................................................................... 136 Manpower .......................................................................................................................................... 140 PROCESSING AND RECOVERY ........................................................................................................... 143 Mineral Processing Methods ............................................................................................................. 143 Background ................................................................................................................................ 143 Ore Processing .................................................................................................................................... 143 Stillwater Concentrator .............................................................................................................. 143 East Boulder Concentrator ........................................................................................................ 147 Concentrator Process Control Sampling ................................................................................. 151 Smelting and Refining ........................................................................................................................ 152 Background ................................................................................................................................ 152 Smelter ......................................................................................................................................... 152 Base Metal Refinery.................................................................................................................... 157 PGM Prill Splits ..................................................................................................................................... 161 Processing Logistics ............................................................................................................................ 161 INFRASTRUCTURE ................................................................................................................................. 163 Stillwater Mine Complex .................................................................................................................... 163 Concentrator Infrastructure ...................................................................................................... 163 Tailings Storage Facilities ........................................................................................................... 163 Power ........................................................................................................................................... 166 Bulk Water ................................................................................................................................... 167 Roads ........................................................................................................................................... 168 Equipment Maintenance .......................................................................................................... 168 Buildings ....................................................................................................................................... 169 Transportation ............................................................................................................................. 171 East Boulder Mine Complex .............................................................................................................. 172 Concentrator Infrastructure ...................................................................................................... 172 Tailings Storage Facilities ........................................................................................................... 172 Power ........................................................................................................................................... 174 Bulk Water ................................................................................................................................... 174 Roads ........................................................................................................................................... 176 Buildings ....................................................................................................................................... 176 Equipment Maintenance .......................................................................................................... 177 Transportation ............................................................................................................................. 178 Dry Fork Waste Rock Storage Area .......................................................................................... 178 Columbus Metallurgical Facility ............................................................................................... 178 MARKET STUDIES .................................................................................................................................. 180 Introduction ........................................................................................................................................ 180 viii PGM Market Overview ...................................................................................................................... 180 Platinum and Palladium Demand and Supply ............................................................................... 181 Demand Drivers .......................................................................................................................... 181 Platinum ....................................................................................................................................... 181 Palladium ..................................................................................................................................... 181 Palladium and Platinum Pricing Outlook ........................................................................................ 181 Metals Marketing Agreements ......................................................................................................... 182 The Columbus Metallurgical Complex .................................................................................... 182 Precious Metals Refining ............................................................................................................ 182 Wheaton International Streaming Agreement ....................................................................... 182 The 2020 Palladium Hedge ....................................................................................................... 183 ENVIRONMENTAL STUDIES, PERMITTING, PLANS, NEGOTIATIONS/AGREEMENTS ........................... 184 Social and Community Agreements ............................................................................................... 184 Environmental Studies, Permitting and Plans .................................................................................. 185 Overview of Environmental Legislation and Regulation ....................................................... 185 Environmental Setting and Factors .......................................................................................... 190 Environmental Studies ................................................................................................................ 190 Permitting Status and Compliance .......................................................................................... 194 Requirements for Environmental Monitoring, Closure and Post Closure, and Management Plans ............................................................................................................................................. 220 Reclamation Plans and Costs ................................................................................................... 229 CAPITAL AND OPERATING COSTS ..................................................................................................... 235 Overview ............................................................................................................................................. 235 Capital Costs ...................................................................................................................................... 235 Background ................................................................................................................................ 235 Stillwater Mine ............................................................................................................................. 235 East Boulder Mine ....................................................................................................................... 239 Columbus Metallurgical Complex ........................................................................................... 242 Operating Costs ................................................................................................................................. 244 Background ................................................................................................................................ 244 Stillwater Mine ............................................................................................................................. 244 East Boulder Mine ....................................................................................................................... 245 Columbus Metallurgical Complex ........................................................................................... 246 ECONOMIC ANALYSIS ....................................................................................................................... 251 Background ........................................................................................................................................ 251 Economic Viability Testing Method ................................................................................................. 251 Economic Assumptions and Forecasts ............................................................................................ 252 Taxation ....................................................................................................................................... 252
ix Metal Price Forecast .................................................................................................................. 252 Discount Rate.............................................................................................................................. 252 DCF Results and Sensitivity Analysis .................................................................................................. 252 DCF Model .................................................................................................................................. 252 Net Present Values ..................................................................................................................... 256 Internal Rate of Return ............................................................................................................... 256 Sensitivity Analysis ....................................................................................................................... 256 OTHER RELEVANT DATA AND INFORMATION .................................................................................... 258 Catalytic Converter Recycling Business .......................................................................................... 258 Background ................................................................................................................................ 258 Recycle Processing .................................................................................................................... 258 Recycling Operations ................................................................................................................ 259 INTEPRETATION AND CONCLUSIONS ................................................................................................ 260 RECOMMENDATIONS ......................................................................................................................... 264 QUALIFIED PERSONS’ CONSENT AND SIGN-OFF .............................................................................. 265 REFERENCES ......................................................................................................................................... 266 List of Figures Figure 1: Location of Sibanye-Stillwater US PGM Operations in Montana ............................... 14 Figure 2: Sibanye-Stillwater US PGM Operations Mineral Title and Tenure Map ..................... 19 Figure 3: Regional Geology of the Stillwater Complex and Surrounds .................................... 33 Figure 4: South to North Sections Through Stillwater Mine Showing Subsurface Geology ..... 34 Figure 5: A Schematic Section through Stillwater Mine Depicting the Horseman Thrust System ............................................................................................................................ 34 Figure 6: General Stratigraphy of the Stillwater Complex ......................................................... 36 Figure 7: Typical Stratigraphic Sequence and Pd-Pt Grade Profiles of the J-M Reef ............. 39 Figure 8: West to East Schematic Section Showing Variability in Stratigraphy and Impact on the J-M Reef at Stillwater Mine ............................................................................... 41 Figure 9: West to East Section Showing Geological Blocks of the J-M Reef at Stillwater Mine ........................................................................................................................................ 42 Figure 10: West to East Section Showing Geological Blocks of the J-M Reef at East Boulder Mine ............................................................................................................................... 43 Figure 11: Underground Definition Diamond Drilling Pattern ...................................................... 46 Figure 12: Drillhole Layout for Stillwater Mine ............................................................................... 48 Figure 13: Drillhole Layout for East Boulder Mine ......................................................................... 49 x Figure 14: Sub-surface Water Basin in the Stillwater East Mine Area .......................................... 54 Figure 15: Hydrogeological Drillhole Locations along Adits in the Stillwater East Section ........ 55 Figure 16: Average Water Inflow at East Boulder Mine ............................................................... 57 Figure 17: Test Sites for In Situ stress Measurements at Stillwater Mine ....................................... 59 Figure 18: Test Sites for In Situ Stress Measurements at East Boulder Mine ................................. 60 Figure 19: Repeat Data Analysis for Stillwater Mine .................................................................... 67 Figure 20: Repeat Sample Data Analysis for East Boulder Mine ................................................. 67 Figure 21: Blank Sample Data Analysis for Stillwater and East Boulder Mines ........................... 68 Figure 22: Laboratory Standard MF-14 Data Analysis ................................................................. 69 Figure 23: Laboratory Standard MF-15 Data Analysis ................................................................. 69 Figure 24: Laboratory Standard MF-16 Data Analysis ................................................................. 69 Figure 25: Laboratory Standard MF-18 Data Analysis ................................................................. 70 Figure 26: Laboratory Standard MF-20 Data Analysis ................................................................. 70 Figure 27: Laboratory Standard MF-21 Data Analysis ................................................................. 70 Figure 28: Scatter plot of Composite UHW vs. 2E Grade for Stillwater Mine .............................. 77 Figure 29: Scatter plot of Composite UHW vs. 2E Grade for East Boulder Mine ........................ 77 Figure 30: Histogram Plot of Composite 2E Grades for Stillwater Mine ...................................... 78 Figure 31: Histogram Plot of Composite 2E Grades for East Boulder Mine ................................ 78 Figure 32: Spatial Analysis of FCW Continuity .............................................................................. 80 Figure 33: Illustration of Reef Channel Wireframe Model Terminated at a Fault at Stillwater Mine ............................................................................................................................... 82 Figure 34: Illustration of Reef Channel Wireframe Model Terminated at Dykes at East Boulder Mine ............................................................................................................................... 83 Figure 35: J-M Reef Geological and Structural Models for Stillwater Mine ................................ 84 Figure 36: J-M Reef Geological and Structural Models for East Boulder Mine .......................... 85 Figure 37: Modelled 2E Grades and Classification for Stillwater Mine ....................................... 88 Figure 38: Modelled 2E Grades and Classification for East Boulder Mine ................................. 89 Figure 39: Blitz Mean 2E Grade (opt) by Easting .......................................................................... 91 Figure 40: Frog Pond East Mean 2E Grade (opt) by Easting....................................................... 91 Figure 41: Mineral Reserve classification for Stillwater Mine ..................................................... 102 Figure 42: Mineral Reserve classification for East Boulder Mine................................................ 103 Figure 43: Overhand and Underhand Ramp and Fill Mining Methods .................................... 108 Figure 44: Sub-level Extraction (Longitudinal) Long Hole Open Stoping ................................. 109 Figure 45: Transverse Long Hole Open Stoping ......................................................................... 110 Figure 46: Generalized Underground Layouts for Stillwater and East Boulder Mines ............. 119 Figure 47: Typical Ramp and Fill Stope Design .......................................................................... 122 Figure 48: LoM RoM ore production schedule for Stillwater Mine ............................................ 127 Figure 49: LoM Production Schedule for East Boulder Mine ..................................................... 129 Figure 50: Stillwater Mine Compressed Air Service Map ........................................................... 135 xi Figure 51: Stillwater East Section Service Water Reticulation ................................................... 136 Figure 52: East Boulder Mine Compressed Air Distribution System ........................................... 139 Figure 53: East Boulder Mine Drill Water Reservoir Layout ......................................................... 140 Figure 54: Block Flow Diagram of the Stillwater Concentrator ................................................. 145 Figure 55: Stillwater Concentrator Actual and Forecast LoM Operational Throughput and Outputs ........................................................................................................................ 146 Figure 56: Stillwater Concentrator Actual and Forecast LoM Operational Data ................... 146 Figure 57: East Boulder Concentrator Simplified Block Flow Diagram ..................................... 148 Figure 58: East Boulder Concentrator Actual and Forecast LoM Operational Throughput and Outputs ................................................................................................................ 150 Figure 59: East Boulder Concentrator Actual and Forecast LoM Operational Data ............. 150 Figure 60: A Simplified Block Flow Diagram of the Smelter ....................................................... 154 Figure 61: Smelter Actual and Forecast LoM Operational Throughput .................................. 156 Figure 62: Smelter LoM Operational Performance, Actual and Forecast .............................. 156 Figure 63: A Simplified Block Flow Diagram of the Base Metal Refinery .................................. 158 Figure 64: Base Metal Refinery Actual and Forecast LoM Operational Throughput and Base Metals Recovered ...................................................................................................... 160 Figure 65: Base Metal Refinery Actual and Forecast LoM Operational Performance ........... 161 Figure 66: Hertzler TSF Knight-Piésold Calculated Elevation Profile .......................................... 165 Figure 67: Stillwater Mine Site Layout .......................................................................................... 171 Figure 68: East Boulder TSF Calculated Elevation Profile ........................................................... 173 Figure 69: East Boulder Mine Site Layout .................................................................................... 177 Figure 70: Stillwater Mine NPV Sensitivity Analysis ...................................................................... 256 Figure 71: East Boulder Mine NPV Sensitivity Analysis ................................................................ 257 List of Tables Table 1: Details of Qualified Persons Appointed by Sibanye-Stillwater US PGM Operations 10 Table 2: Technical Experts/Specialists Supporting the Qualified Persons ............................... 12 Table 3: Summary of Sibanye-Stillwater US PGM Operations Mineral Title and Tenure ......... 16 Table 4: Summary Details of Mining Claims Subject to Royalties ............................................ 20 Table 5: Details of Historical Royalty Payments to Franco-Nevada and Mouat .................... 20 Table 6: Historical Surface and Adit Exploration Drillholes ....................................................... 27 Table 7: Historical Production for Stillwater and East Boulder Mines ....................................... 29 Table 8: Summary Description of Plant, Property and Equipment for the Sibanye-Stillwater US PGM Operations ...................................................................................................... 30 Table 9: Summary of Geotechnical Parameters ...................................................................... 60 Table 10: Details of the In-house Standards ................................................................................ 68 Table 11: Summary Indicating the Impact of Replacing Zero Values in the Datasets ............ 76 xii Table 12: Capping Grades and Yield Limits Employed for the Mineral Resource Evaluation 79 Table 13: Summary of Standardised Variogram Parameters for FOZPT .................................... 80 Table 14: Summary of Standardised Variogram Parameters for FCW ...................................... 80 Table 15: Search Parameters Employed for Grade Estimation ................................................. 87 Table 16: Domain Global Means Calculated from Declustered Data ..................................... 87 Table 17: Comparison of the Estimated and Evaluation Cut Composite Grades ................... 90 Table 18: Parameters Employed for Cut-off Grade Calculation and Mineral Reserve Declaration .................................................................................................................... 95 Table 19: Mineral Resource Estimates Inclusive of Mineral Reserves at the End of the Fiscal Year Ended December 31, 2021 Based on Pd and Pt Price of $1 500/oz ................ 96 Table 20: Mineral Resource Estimates Exclusive of Mineral Reserves at the End of the Fiscal Year Ended December 31, 2021 Based on Pd and Pt Price of $1 500/oz ................ 97 Table 21: Mineral Reserve Estimates Inclusive of Mineral Reserves at the End of the Fiscal Year Ended December 31, 2021 Based on Pd and Pt Price of $1 250/oz .............. 104 Table 22: Mining method frequency of use at Stillwater and East Boulder Mines ................. 108 Table 23: Stope Extraction Ratios ............................................................................................... 111 Table 24: Planning Parameters for Stoping for Stillwater Mine ................................................ 121 Table 25: Planning Parameters for Primary Development for Stillwater Mine ........................ 121 Table 26: Planning Parameters for Stoping for East Boulder Mine ........................................... 121 Table 27: Planning Parameters for Primary Development for East Boulder Mine .................. 121 Table 28: Mining Dilution Factors and Dilution Methodology for Stillwater Mine ................... 123 Table 29: Mining Dilution Factors and Dilution Methodology for East Boulder Mine ............. 124 Table 30: LoM Production Schedule for Stillwater Mine ........................................................... 127 Table 31: LoM Production Schedule for East Boulder Mine ..................................................... 128 Table 32: Stillwater West Section Current Mechanised Mining Equipment Quantities .......... 129 Table 33: Stillwater East Section Current Mechanised Mining Equipment Quantities ........... 130 Table 34: East Boulder Mine Mechanised Mining Equipment Quantities ............................... 130 Table 35: LoM Manpower Plan for Stillwater Mine .................................................................... 141 Table 36: LoM Manpower Plan for East Boulder Mine .............................................................. 142 Table 37: Stillwater Concentrator Actual and Forecast LoM Operational Throughput and Outputs ........................................................................................................................ 145 Table 38: East Boulder Concentrator Actual and Forecast LoM Operational Throughput and Outputs ................................................................................................................ 149 Table 39: Smelter Historical and Budget Operational Data .................................................... 155 Table 40: Base Metal Refinery Historical and Forecast LoM Operational Data ..................... 160 Table 41: Summary of Pt and Pd Prill Split Data ........................................................................ 161 Table 42: Comparison of Sibanye-Stillwater and Market Consensus Prices ........................... 182 Table 43: Regulatory Agencies and Permits, Licenses or Approval Requirements ................ 187
xiii Table 44: Summary of Recent Environmental Studies Associated with Expansions at Stillwater Mine ............................................................................................................. 192 Table 45: Summary of Recent Environmental Studies Associated with Expansions at Stillwater Mine ............................................................................................................. 194 Table 46: Permits Status Summary for the Sibanye-Stillwater US PGM Operations ................. 199 Table 47: Stillwater Mine Operations Actionable Reportable Documents ............................. 221 Table 48: Stillwater Mine Closure Actionable Reportable Documents ................................... 222 Table 49: Stillwater Mine Post Closure Actionable Reportable Documents ........................... 223 Table 50: East Boulder Mine Operations Actionable Reportable Documents ....................... 225 Table 51: East Boulder Mine Closure Actionable Reportable Documents ............................. 227 Table 52: East Boulder Mine Post Closure Actionable Reportable Documents ..................... 227 Table 53: Stillwater Mine Reclamation Schedule...................................................................... 230 Table 54: Stillwater Mine Closure Monitoring and Maintenance Schedule ........................... 231 Table 55: East Boulder Mine Reclamation Schedule ................................................................ 232 Table 56: East Boulder Mine Closure Monitoring and Maintenance Schedule ..................... 232 Table 57: Stillwater Mine Actual and LoM Capital Schedule .................................................. 238 Table 58: East Boulder Mine Actual and LoM Capital Schedule ............................................ 241 Table 59: Columbus Metallurgical Complex Actual and LoM Capital Expenditure ............. 243 Table 60: Actual and LoM Operating Costs for Stillwater Mine ............................................... 248 Table 61: Actual and LoM Operating Cost for East Boulder Mine .......................................... 249 Table 62: Actual and LoM Operating Costs for the Columbus Metallurgical Complex........ 250 Table 63: Abridged Cash Flow Results ....................................................................................... 253 Table 64: Net Present Values at Different Discount Rates ........................................................ 256 Table 65: Combined Sibanye-Stillwater US PGM Operations, NPV5% Sensitivity to Pd and Pt Price Variation ............................................................................................................. 257 1 EXECUTIVE SUMMARY Introduction This Technical Report Summary was prepared by in-house Qualified Persons for filing by Sibanye- Stillwater Limited (Sibanye-Stillwater), which is an independent international precious metals mining company with a diverse mineral asset portfolio. It covers Sibanye-Stillwater's wholly owned platinum group metal (PGM) operations in Montana in the United States (the Sibanye-Stillwater US PGM Operations). These operations comprise integrated mines and concentrator plants situated at the Stillwater and East Boulder Mines and mineral beneficiation facilities (a smelter, base metal refinery, PGM recycling plant and an analytical laboratory) at the Columbus Metallurgical Complex. Owing to the integrated nature of the mining, ore processing and mineral beneficiation operations, the Sibanye- Stillwater US PGM Operations constitute a single unit (material property). This Technical Report Summary for the Sibanye-Stillwater US PGM Operations supports the disclosure of the Mineral Resource and Mineral Reserve estimates for Stillwater and East Boulder Mines as at 31 December 2021. Due to Sibanye-Stillwater’s listing on both the New York Stock Exchange (NYSE) and Johannesburg Stock Exchange (JSE or JSE Limited), the Mineral Resource and Mineral Reserve estimates were prepared and reported according to the United States Securities and Exchange Commission's (SEC's) Subpart 1300 of Regulation S-K and following the guidelines of the 2016 Edition of the South African Code for the Reporting of Exploration Results, Mineral Resources and Mineral Reserves (The SAMREC Code, 2016), Section 12 of the JSE Listing Requirements. This Technical Report Summary has been prepared according to the SEC's Subpart 1300 of Regulation S-K disclosure requirements. Property Description, Mineral Rights and Ownership Stillwater and East Boulder Mines are well-established, ongoing mines situated 13 miles apart, extracting the J-M Reef in the Stillwater Complex and processing the ore at onsite concentrators to produce PGM concentrates, which are further beneficiated at the Columbus Metallurgical Complex. A network comprising state roads and Sibanye-Stillwater maintained mine access roads connect the mines, local towns and the Columbus Metallurgical Complex. Regional power infrastructure is already installed providing adequate power supplies to the operations. Climatic conditions in this area do not significantly affect the operations at the three sites. Sibanye-Stillwater has title (leased or held Mining Claims) in perpetuity over the entirety of the known outcrop of the J-M Reef along the Beartooth Mountains in Montana. It also holds surface rights (Tunnel and Mill Site Claims) over key land parcels on which mining infrastructure is built at Stillwater and East Boulder Mines or which provide servitude required to access the reef. The claims total 1 704 in number and cover an area of 24 156 acres. A total of 898 claims are subject to the Franco-Nevada Royalty and Mouat Royalty, with annual royalty payments based on Net Smelter Return for the palladium and platinum produced while considering the cost of production. There are no material legal proceedings in relation to the Sibanye-Stillwater US PGM Operations discussed in this Technical Report Summary. Despite the simplified regulatory framework for mining prevailing in the Unites States, the granting of permits and approvals for building a mine or expansions of existing mining operations in Montana is 2 costly and can be a lengthy process. The 21-year-old Good Neighbor Agreement between Sibanye- Stillwater and the local authorities has facilitated seamless stakeholder participation in the scoping and review of applications for permits and approvals. Geology and Mineralisation The J-M Reef mined at Stillwater and East Boulder Mines is a world class primary magmatic reef-type Pd- Pt deposit occurring at a consistent stratigraphic level in the Stillwater Complex. It is a laterally continuous magmatic reef-type PGM deposit defined as the Pd-Pt rich stratigraphic interval, occurring mainly within a troctolite (OB-I zone) of the Lower Banded Series. At Stillwater Mine, the dip of the J-M Reef northwards varies from approximately vertical in the eastern part to approximately 62° in the central part and between 45° and 50° in the Upper West sector of the mine. However, dips at East Boulder Mine are less variable and are on average 50° towards the northeast. Having retained most of its primary magmatic characteristics, the J-M Reef is laterally continuous, very coarse-grained and identified by the presence of 0.25% to 3% visible disseminated copper-nickel sulphide minerals within the OB-I zone and using hangingwall markers. However, sampling and laboratory analysis provide the definitive data used to confirm the presence of the J-M Reef and to determine its PGM tenor. A high thickness and grade variability over short ranges (stope level) characterises the J-M Reef and this is more pronounced at Stillwater Mine (West Section) where the mineralisation may occur as a unique mixture of "ballrooms", low-grade and normal J-M Reef mineralisation over short intervals. The combined effect of dip, thickness and grade variability affects the way in which the J-M Reef is evaluated, but this resembles the conventional evaluation approaches employed for other PGM reefs in layered igneous complexes. Exploration Status, Development and Operations and Mineral Resource Estimates Extensive exploration for PGMs since the 1960s dominated by diamond drilling at Stillwater and East Boulder Mines produced data utilised for the evaluation of the J-M Reef. The exploration was focused on the appraisal and evaluation of the J-M Reef along the Beartooth Mountains in Montana within Sibanye-Stillwater’s title areas and led to the establishment of Stillwater and East Boulder Mines in 1986 and 2002, respectively. The mines have been operational for most of the time except for a short-lived stoppage in 2008. The extensive drillhole database accumulated from moderately spaced surface diamond drilling and closely spaced underground definition diamond drilling from footwall lateral drifts, complemented by mining and ore processing information, was used for the estimation of Mineral Resources for Stillwater and East Boulder Mines. Geotechnical and hydrogeological data has also been collected in parallel with the geological data used for Mineral Resource estimation. In all cases, the approaches employed for the collection, validation, processing and interpretation of the drillhole data are in line with industry best practice. A combination of long-range continuity, occurrence at a consistent stratigraphic position and within a consistent stratigraphic sequence, localised thickness and grade variability and steep dips influences the estimation approaches employed for the J-M Reef. The construction of three-dimensional geological models and the estimation of grades in areas supported by both surface and definition 3 drillhole data classified as Measured Mineral Resources and the remainder of the areas supported by surface drillhole data classified as Indicated or Inferred Mineral Resources are appropriate for the style and variability of the J-M Reef. In both cases, the available drillhole data permitted grade interpolation into individual blocks through simple kriging and classification of the estimates as Inferred, Indicated or Measured on account of geological confidence. The Mineral Resource estimates for Stillwater and East Boulder Mines below are reported from grade block models for the mines as at December 31, 2021 and as inclusive or exclusive of Mineral Reserves. These estimates are in situ estimates of tonnage and grades reported at a minimum mining width of 7.5ft applicable for the dominant Ramp and Fill mining method used at the mines, and at a Pt + Pd (2E) cut-off grade of 02opt (6.86g/t) at Stillwater Mine and 0.05opt (1.71g/t) at East Boulder Mine. In addition, these estimates account for geological losses due to disturbance of the J-M Reef continuity by geological structures. Description Mineral Resources Inclusive of Mineral Reserves Imperial Category Mine Tons (Million) Pd (opt) Pt (opt) 2E (opt) 2E Content (Moz) Measured Stillwater 24.0 0.35 0.10 0.46 10.9 East Boulder 20.0 0.31 0.09 0.40 7.9 0 Subtotal/Average 44.0 0.33 0.09 0.43 18.9 Indicated Stillwater 34.5 0.32 0.09 0.41 14.3 East Boulder 30.6 0.30 0.08 0.39 11.8 Subtotal/Average 65.1 0.31 0.09 0.40 26.1 Measured + Indicated Stillwater 58.5 0.34 0.10 0.43 25.2 East Boulder 50.6 0.31 0.08 0.39 19.8 Subtotal/Average 109.1 0.32 0.09 0.41 45.0 Inferred Stillwater 67.7 0.28 0.08 0.35 24.0 East Boulder 57.5 0.28 0.08 0.36 20.6 Subtotal/Average 125.2 0.28 0.08 0.36 44.6 Metric Category Mine Tonnes (Million) Pd (g/t) Pt (g/t) 2E (g/t) 2E Content (Moz) Measured Stillwater 21.7 12.16 3.46 15.63 10.9 East Boulder 18.1 10.66 2.96 13.62 7.9 Subtotal/Average 39.9 11.48 3.23 14.71 18.9 Indicated Stillwater 31.3 11.06 3.15 14.22 14.3 East Boulder 27.8 10.38 2.88 13.26 11.8 Subtotal/Average 59.1 10.74 3.03 13.77 26.1 Measured + Indicated Stillwater 53.0 11.51 3.28 14.79 25.2 East Boulder 45.9 10.49 2.91 13.40 19.8 Subtotal/Average 99.0 11.04 3.11 14.15 45.0 Inferred Stillwater 61.5 9.45 2.69 12.14 24.0 East Boulder 52.2 9.61 2.67 12.28 20.6 Subtotal/Average 113.6 9.52 2.68 12.21 44.6 2E Cut-off Grade Stillwater Mine – 0.20opt (6.86g/t) 2E Cut-off Grade East Boulder Mine – 0.05opt (1.71g/t) Pd Price – $1 500/oz Pt Price – $1 500/oz 2E Recovery Stillwater Mine – 92.3% 2E Recovery East Boulder Mine – 91.0% Pd:Pt Ratio Stillwater Mine – 3.51:1 Pd:Pt Ratio East Boulder Mine – 3.60:1
4 Description Mineral Resources Exclusive of Mineral Reserves Imperial Category Mine Tons (Million) Pd (opt) Pt (opt) 2E (opt) 2E Content (Moz) Measured Stillwater 8.7 0.34 0.10 0.44 3.8 East Boulder 8.0 0.31 0.09 0.40 3.1 Subtotal/Average 16.6 0.33 0.09 0.42 6.9 Indicated Stillwater 9.9 0.33 0.09 0.43 4.2 East Boulder 12.1 0.30 0.08 0.38 4.6 Subtotal/Average 22.0 0.31 0.09 0.40 8.8 Measured + Indicated Stillwater 18.6 0.34 0.10 0.43 8.0 East Boulder 20.0 0.30 0.08 0.38 7.7 Subtotal/Average 38.6 0.32 0.09 0.41 15.7 Inferred Stillwater 67.7 0.28 0.08 0.35 24.0 East Boulder 57.5 0.28 0.08 0.36 20.6 Subtotal/Average 125.2 0.28 0.08 0.36 44.6 Metric Category Mine Tonnes (Million) Pd (g/t) Pt (g/t) 2E (g/t) 2E Content (Moz) Measured Stillwater 7.9 11.68 3.33 15.00 3.8 East Boulder 7.2 10.61 2.95 13.55 3.1 Subtotal/Average 15.1 11.16 3.14 14.31 6.9 Indicated Stillwater 9.0 11.35 3.23 14.58 4.2 East Boulder 10.9 10.14 2.81 12.95 4.6 Subtotal/Average 19.9 10.68 3.00 13.68 8.8 Measured + Indicated Stillwater 16.9 11.50 3.28 14.78 8.0 East Boulder 18.2 10.32 2.87 13.19 7.7 Subtotal/Average 35.0 10.89 3.06 13.95 15.7 Inferred Stillwater 61.5 9.45 2.69 12.14 24.0 East Boulder 52.2 9.61 2.67 12.28 20.6 Subtotal/Average 113.6 9.52 2.68 12.21 44.6 2E Cut-off Grade Stillwater Mine – 0.20opt (6.86g/t) 2E Cut-off Grade East Boulder Mine – 0.05opt (1.71g/t) Pd Price – $1 500/oz Pt Price – $1 500/oz 2E Recovery Stillwater Mine – 92.3% 2E Recovery East Boulder Mine – 91.0% Pd:Pt Ratio Stillwater Mine – 3.51:1 Pd:Pt Ratio East Boulder Mine – 3.60:1 Mining Methods, Ore Processing, Infrastructure and Mineral Reserve Estimates Stillwater and East Boulder Mines are mature operations extracting the J-M Reef to produce PGMs and base metals using well-established mining and ore processing methods. Most of the permanent infrastructure required to access the underground operations is already established and being upgraded where necessary to accommodate production increases anticipated in the LoM plans for Stillwater Mine (Stillwater East Expansion). Detailed LoM plans for Stillwater and East Boulder Mines support the Mineral Reserve estimates presented below and reported as at December 31, 2021. 5 Description Mineral Reserves Imperial Category Mine Tons (Million) Pd (g/t) Pt (g/t) 2E (opt) 2E Content (Moz) Proved Stillwater 5.1 0.39 0.11 0.50 2.6 East Boulder 3.9 0.30 0.08 0.38 1.5 Subtotal/Average 9.0 0.35 0.10 0.45 4.1 Probable Stillwater 39.4 0.27 0.08 0.35 13.7 East Boulder 26.8 0.28 0.08 0.36 9.6 Subtotal/Average 66.3 0.27 0.08 0.35 23.2 Proved + Probable Stillwater 44.6 0.28 0.08 0.36 16.2 East Boulder 30.7 0.28 0.08 0.36 11.1 Total/Average 75.3 0.28 0.08 0.36 27.3 Metric Category Mine Tonnes (Million) Pd (g/t) Pt (g/t) 2E (g/t) 2E Content (Moz) Proved Stillwater 4.6 13.42 3.82 17.25 2.6 East Boulder 3.5 10.16 2.82 12.98 1.5 Subtotal/Average 8.2 12.02 3.39 15.41 4.1 Probable Stillwater 35.8 9.24 2.63 11.87 13.7 East Boulder 24.3 9.59 2.66 12.26 9.6 Subtotal/Average 60.1 9.38 2.64 12.03 23.2 Proved + Probable Stillwater 40.4 9.72 2.77 12.49 16.2 East Boulder 27.9 9.67 2.68 12.35 11.1 Total/Average 68.3 9.70 2.73 12.43 27.3 2E Cut-off Grade Stillwater Mine – 0.20opt (6.86g/t) 2E Cut-off Grade East Boulder Mine – 0.05opt (1.71g/t) Business Planning and Mineral Reserve Declaration Pd and Pt Price – $1 250/oz Cut-off Determination Pd Price – $1 250/oz Cut-off Determination Pt Price – $1 250/oz 2E Recovery Stillwater Mine – 92.3% 2E Recovery East Boulder Mine – 91.0% Pd:Pt Ratio Stillwater Mine – 3.51:1 Pd:Pt Ratio East Boulder Mine – 3.60:1 The Ramp and Fill method, which is the dominant mining method (more than 80%), is well-understood at the mines and suited to the character and attitude of the J-M Reef. The remainder of the stopes are mined through the Sub-level Extraction Long Hole stoping, with the Captive Cut and Fill mining method having been phased out for safety reasons. Mine designs for Stillwater and East Boulder Mines incorporate the hydrogeological and geotechnical models constructed from appropriate groundwater and geotechnical testwork, the extensive geotechnical database and historical experiences at the mines. Ore extraction ratios of 60% to 90% for stopes and 40% to 50% for the entire mine are typical for the mining methods employed. Ground support designs and procedures employed at the mines, which have been refined through ongoing continuous improvement initiatives, have eliminated occurrences of major fall of ground events. No significant groundwater inflows are experienced except when development extends into new areas, but these are addressed using existing procedures combining probe drilling, the use of drainholes and routine mine dewatering using cascading water pumps. The LoM production plans for Stillwater and East Boulder Mines were developed through Mineral Resources to Mineral Reserve conversion processes that utilised dilution factors and mining (stoping and development) parameters informed by historical reconciliation results and performance. The use of factors aligned to historical performance enhances the likely achievability of the plans. The LoM plan for Stillwater Mine envisages an important ore production tonnage ramp up from the current 898 thousand tons to a FY2027 steady state average of 1.45 million tons per annum milled associated 6 with the Stillwater East Section and ongoing steady state production until FY2056. With production levels for East Boulder Mine at steady state after conclusion of the Fill the Mill Project, the LoM plan envisages ongoing production at the steady state average of 785 thousand tons per annum milled until FY2049 followed by production at the reduced rate of 726 thousand tons per annum milled until in FY2061. Economic viability testing of the LoM plans demonstrated that extraction of the scheduled Indicated and Measured Mineral Resources is economically justified, and the declaration of Mineral Reserves is appropriate. In general, the LoM plans include appropriate staffing levels which are informed by historical experience. Most of the key infrastructure for mining is already installed at the Stillwater and East Boulder Mines, with the additional infrastructure required for the expanded operations at Stillwater Mine at advanced stages of installation. Similarly, most of the mining equipment required for the execution of the LoM plans is already available at the mines, with the remaining equipment required at Stillwater Mine already purchased and awaiting delivery. Bulk power and water supplies are secure, and the infrastructure upgrades required at both sites have been completed ahead of the achievement of steady state production levels. The concentrators employed for ore processing at the Stillwater and East Boulder Mines have been operational for several decades and use proven technology and process routes. The forecast metallurgical recoveries of approximately 92% and 91% respectively for the Stillwater and East Boulder Concentrators, and production profiles employed in the LoM plans are informed by historical experience. A plant capacity upgrade from 1.1 million tons to 1.45 million tons per annum is under way at Stillwater Mine to accommodate increasing RoM ore production from the Stillwater East Section. The East Boulder Concentrator has historically been operated below the 850 thousand tons per annum capacity, and sustainable ore processing at 785 thousand tons per annum should be achievable without significant additional capital expenditure. There is adequate storage capacity for the tailings resulting from ore processing at the concentrators at Stillwater and East Boulder Mines in the short to medium term. However, additional tailings storage capacity will be required for the remainder of the LoMs. Plans being considered for the upgrading of the tailings storage (TSF) capacities for the long-term disposal of the tailings include storage capacity upgrades at existing TSFs through elevation lifts and lateral expansions as well as the establishment of new TSFs. Sibanye-Stillwater is aware of the long timeframes for the granting of permits and related approvals of the upgrades and establishment of new TSFs. Accordingly, it will expedite the finalisation of the long-term tailings storage plans to enable the undertaking of the requisite studies needed for permit and approval applications. The smelter and base metal refinery at the Columbus Metallurgical Complex utilise proven technology and process routes for the processing of concentrate and matte, respectively. There are no plans to introduce new processing technology at the processing facilities, with the modest capacity upgrades and debottlenecking projects implemented to accommodate the increased concentrate production at Stillwater and East Boulder Mines currently being concluded. 7 Capital and Operating Cost Estimates and Economic Analysis The LoM plans for Stillwater and East Boulder Mines and the Columbus Metallurgical Complex provide for appropriate capital expenditure budgets for the sustainability of the operations and for the various capacity upgrades and production expansions envisaged. Sustaining capital costs are benchmarked to historical capital expenditure. Similarly, the forecast operating costs included in the LoM plans are based on historical experience at the operations. Sustaining capital costs cater for mine and surface equipment, capitalised development, projects, infrastructure and environmental capital expenditure. The capital budget for Stillwater Mine ranges between $13.55 million and $352.39 million (average $89.46 million) per annum from FY2022 to FY2051, totalling $2.69 billion over the FY2022 to FY2055 period, and is dominated by the costs of capitalised development and mine and surface equipment (approximately 62% to 97% of the annual capital costs). For East Boulder Mine, the capital costs vary from approximately $18.8 million to $57.0 million (average $33.78 million) annually from FY2022 to FY2058, totalling $1.26 billion over the FY2022 to FY2061 period, also dominated by capitalised development and mine and surface equipment costs except for periods associated with TSF expansions or construction of new TSFs. Stillwater Mine, which is ramping up production, has budgeted operating costs ranging from approximately $275/ton to $316/ton processed, with mining contributing 88% to 91% of the total cost and surface facilities (concentrator, sand and paste plants, ore hoisting and tailings storage management) contributing the remainder. At steady state, after FY2027, the costs are set to decrease to an approximate average of $244/ton processed, with mining accounting for 90% of the total cost. For East Boulder Mine, operating costs of $165/ton to $215/ton milled are forecast with mining accounting for 87% to 90% of the total cost and surface facilities accounting for the remainder. Credits from the recycling business and by-product metals exceed the operating cost for smelting and base metal refining for as long as both Stillwater and East Boulder Mines are producing ore at the steady state production levels. This underscores the importance of the catalyst recycling business and associated by-products to the Sibanye-Stillwater US PGM Operations. The market fundamentals for palladium and platinum are forecast to remain in place in the foreseeable future. The budgeted capital and operating costs, forecast metal prices and other economic assumptions utilised for economic viability testing of the LoM plans are reasonable. The post-tax flows for Stillwater and East Boulder Mines and the integrated Sibanye-Stillwater US PGM Operations derive the DCF results (NPVs) contained in the table below at Sibanye-Stillwater’s weighted average cost of capital (discount rate) as at December 31, 2021 of 5%. The table also clearly indicates the discount rate sensitivity of the operations. The Internal Rate of Return (IRR) of the Sibanye-Stillwater US PGM Operations is 182%. Mineral Asset Units Real Discount Rate 0.00% 2.50% 5.00% 7.50% East Boulder Mine NPV$ million $4 324 $2 639 $1 764 $1 272 Stillwater Mine NPV $ million $3 812 $2 429 $1 625 $1 137 Sibanye-Stillwater US PGM Operations NPV $ million $8 162 $5 079 $3 394 $2 411
8 The table below shows two-variable sensitivity analysis of the NPV5% to ±10% variance in both palladium and platinum price. This demonstrates robust results over material economic input range variances. NPV5% $ million Palladium Price Variance from Base Assumption Variance -10% -5% 0% 5% 10% Platinum Price Variance from Base Assumption -10% $2 327 $2 736 $3 145 $3 554 $3 962 -5% $2 452 $2 861 $3 270 $3 678 $4 087 0% $2 577 $2 986 $3 394 $3 803 $4 212 5% $2 702 $3 111 $3 519 $3 928 $4 337 10% $2 827 $3 235 $3 644 $4 053 $4 462 With the results of the economic viability testing of the LoM plans demonstrating that extraction of the scheduled Indicated and Measured Mineral Resources is economically justified, the declaration of Mineral Reserves is appropriate. Permitting Requirements Sibanye-Stillwater has in place all the necessary rights and approvals to operate the mines, concentrators, TSFs, waste rock storage dumps, smelter and associated ancillary facilities associated with the operations. Appropriate additional studies, designs and permitting documents have been or are in the process of being completed to support the planned operational expansions. Current permit and license violations are being corrected and environmental impacts are being managed in close consultation with the appropriate agencies. There are reasonable prospects that the operator’s licence to operate on these premises is secure for the foreseeable future, unless terminated by regulatory authorities for other reasons. Bonding amounts are deemed reasonable and appropriate for the permitted activities and obligations, contingent to final resolution of the Stillwater Mine bond negotiations with the regulatory authorities. Furthermore, based on assessment of the current permits, technical submittals, regulatory requirements and project compliance history, continued acquisition of permit approvals should be possible and there is low risk of rejections of permit applications by the regulatory for the foreseeable future. Conclusions and Recommendations The Qualified Persons could not identify any material risks that would affect the Mineral Resources and Mineral Reserves reported for Stillwater and East Boulder Mines. Most of the issues identified are low to medium risks which include the following: • Inadequate tailings storage capacity in the long term due to permitting delays; • Power losses due to inclement weather; • Unplanned production cost escalation; • Failure to effectively execute the LoM plan; • Higher groundwater inflows than experienced previously; and • Excavation failure due to geotechnical conditions never experienced previously. Sibanye-Stillwater is fully aware of the low to medium risks identified and has mitigation measures in place to minimise the impact of the risks on the mining, ore processing and mineral beneficiation operations in Montana. 9 INTRODUCTION Registrant This Technical Report Summary was prepared for Sibanye-Stillwater Limited (Sibanye-Stillwater) and covers Sibanye-Stillwater's wholly owned platinum group metal (PGM) operations in Montana in the United States of America (the Sibanye-Stillwater US PGM Operations). Sibanye-Stillwater (the registrant) is an independent international precious metals mining company with a diverse mineral asset portfolio comprising PGM operations in the United States and Southern Africa, gold operations and projects in South Africa, and copper, , lithium, gold and PGM exploration properties and mining operations in North and South America as well as a lithium project in Finland. It is domiciled in South Africa and listed on both the Johannesburg Stock Exchange (JSE or JSE Limited) and New York Stock Exchange (NYSE). The Sibanye-Stillwater US PGM Operations comprise integrated mines and concentrator plants situated at the Stillwater and East Boulder mining complexes (Mines) as well as the mineral beneficiation facilities (a smelter, base metal refinery, PGM recycling plant and an analytical laboratory) at the Columbus Metallurgical Complex (Figure 1). Sibanye-Stillwater owns the Sibanye-Stillwater US PGM Operations through its wholly owned subsidiaries, Sibanye Platinum (Pty) Limited, Sibanye Platinum International Holdings (Pty) Limited, Thor US HoldCo Incorporated and Stillwater Mining Company (SMC). Compliance Due to listings on both the JSE (Code SSW) and NYSE (Code SBSW), Sibanye-Stillwater's Mineral Resources and Mineral Reserves are compiled and reported following the guidelines of the 2016 Edition of the South African Code for the Reporting of Exploration Results, Mineral Resources and Mineral Reserves (The SAMREC Code, 2016), Section 12 of the JSE Listing Requirements and the United States Securities and Exchange Commission's (SEC's) Subpart 1300 of Regulation S-K. The Qualified Person has prepared this Technical Report Summary and the Mineral Resources and Mineral Reserves for the Sibanye- Stillwater US PGM Operations according to the SEC's Subpart 1300 of Regulation S-K disclosure requirements. Terms of Reference and Purpose of the Technical Report This Technical Report Summary for the Sibanye-Stillwater US PGM Operations reports the Mineral Resource and Mineral Reserve estimates for Stillwater and East Boulder Mines as at 31 December 2021. The Qualified Persons can confirm that this report is the first Technical Report Summary for the Sibanye- Stillwater US PGM Operations prepared under the SEC's Subpart 1300 of Regulation S-K disclosure requirements. Stillwater and East Boulder Mines are ongoing, established mines extracting the J-M Reef in the Stillwater Complex. The J-M Reef ore produced by the mines is processed at integrated concentrator plants situated at the mines to produce PGM-base metal concentrate which is beneficiated further at the smelter and base metal refinery situated at the Columbus Metallurgical Complex. The Sibanye-Stillwater US PGM Operations constitute a single unit (material property) owing to the integrated nature of the 10 mining and ore processing at the Stillwater and East Boulder Mines and the mineral beneficiation operations at the Columbus Metallurgical Complex. This Technical Report Summary has been compiled by in-house Qualified Persons for Mineral Resources and Mineral Reserves who were appointed by Sibanye-Stillwater. The Qualified Persons are Technical Experts/Specialists registered with professional bodies that have enforceable codes of conduct (Table 1). The Qualified Persons with responsibility for reporting and sign-off of the Mineral Resources for Stillwater and East Boulder Mines are Jeff Hughs and Jennifer Evans, respectively. Both Qualified Persons are Professional Geologists with more than five years of experience relevant to the estimation and reporting of Mineral Resources and the mining of the J-M Reef at Stillwater and East Boulder Mines. The Qualified Person with responsibility for reporting and sign-off of the Mineral Reserves for both mines is Justus Deen. Justus is a Registered Member of the Society of Mining, Metallurgy and Exploration with more than five years of experience relevant to the estimation and reporting of Mineral Reserves and the mining of the J-M Reef at Stillwater and East Boulder Mines. Other than normal compensation specified in their employment contracts, the Qualified Persons did not receive any professional fees for the preparation of this Technical Report Summary for the Sibanye- Stillwater US PGM Operations. In addition, the Qualified Persons who contributed to this Technical Report Summary do not have any material interest in either Sibanye-Stillwater or the Sibanye-Stillwater US PGM Operations beyond formal employment. Table 1: Details of Qualified Persons Appointed by Sibanye-Stillwater US PGM Operations Name Position Area of Responsibility Academic and Professional Qualifications Justus Deen Technical Services Manager - Engineering Lead Qualified Person Mineral Reserves – Stillwater and East Boulder Mines Bachelor of Science - Geology, Master of Science – Mining Engineering Registered Mining Engineer (SME Reg. No. 04227906RM) Jeff Hughs Technical Services Manager - Geology Qualified Person Mineral Resources – Stillwater Mine Bachelor of Science - Geology American Institute of Professional Geologists - Certified Professional Geologist (AIPG CPG – 11792) Jennifer Evans Senior Geologist Qualified Person Mineral Resources – East Boulder Mine Bachelor of Science - Geology American Institute of Professional Geologists - Certified Professional Geologist (AIPG CPG – 11669) Matt Ladvala Senior Geologist Qualified Person Mineral Resources – Stillwater Mine Bachelor of Science - Geology American Institute of Professional Geologists - Certified Professional Geologist (AIPG CPG – 11941) Kevin Butak Senior Geologist Qualified Person Mineral Resources – Stillwater Mine Master of Science - Geology American Institute of Professional Geologists - Certified Professional Geologist (AIPG CPG – 12012) Sources of Information The J-M Reef outcrop is known from historical exploration and the Mineral Resource estimates for Stillwater and East Boulder Mines contained in this Technical Report Summary have been estimated from the extensive surface and underground drillhole database. These Mineral Resources are the basis for the Mineral Reserve estimates reported for the mines. Furthermore, the Mineral Reserve estimates are based on detailed Life of Mine (LoM) plans and technical studies completed internally by the Sibanye- 11 Stillwater US PGM Operations personnel utilising modifying factors and capital and operating costs which are informed by historical experience at the mines. Sibanye-Stillwater (the registrant) provided most of the technical data and information utilised for the preparation of the Technical Report Summary for the Sibanye-Stillwater US PGM Operations. The surface and underground drillhole data is stored in an electronic drillhole database. Much of the technical information is contained in a variety of internal reports documenting various internal technical studies undertaken in support of the current and planned operations, historical geological work and production performance at Stillwater and East Boulder Mines and the Columbus Metallurgical Complex. Sibanye- Stillwater also provided the forecast economic parameters and assumptions employed for cut-off grade determination, the assessment of prospects for economic extraction of the Mineral Resources and the assessment of economic viability of the LoM plans underlying the Mineral Reserves. Other supplementary information was sourced from the public domain and these sources are acknowledged in the body of the report and listed in the References Section of this Technical Report Summary (Section 26). Site Inspection by Qualified Persons The Qualified Persons for Mineral Resources and Mineral Reserves who authored this Technical Report Summary and the supporting Technical Experts/Specialists are all in-house employees who work at the Sibanye-Stillwater US PGM Operations. By virtue of their employment, the Qualified Persons visit Stillwater and East Boulder Mines and the Columbus Metallurgical Complex regularly in the course of carrying out their normal duties. Accordingly, confirmatory site visits for the specific purposes of this Technical Report Summary were not warranted. Units, Currencies and Survey Coordinate System In the United States of America (USA or US), imperial units are utilised for all measurements and the reporting of quantities at the Sibanye-Stillwater US PGM Operations. Accordingly, the US imperial units are utilised throughout this Technical Report Summary. However, the Mineral Resource and Mineral Reserve estimates are also reported in metric units. All the metal prices and costs are quoted in the US$ currency and, as such, no exchange rates have been used in the Technical Report Summary. The coordinate system employed for all the surface surveys and maps shown in this Technical Report Summary is based on the North American Datum of 1983 (NAD83) State Plane. However, the underground surface surveys and maps for Stillwater and East Boulder Mines are based on the local mine grid, which is in turn based on the North American Datum of 1927 (NAD27) State Plane with a 20º clockwise rotation for alignment of the eastings with the roughly east to west strike direction of the J-M Reef.
12 RELIANCE ON INFORMATION PROVIDED BY REGISTRANT The Qualified Persons have relied on information provided by the Sibanye-Stillwater US PGM Operations and Sibanye-Stillwater (the registrant) in preparing the findings and conclusions regarding the following aspects of the modifying factors outside of the Qualified Persons’ expertise: • Macroeconomic trends, data and assumptions, and commodity prices – Section 21; • Marketing information – Section 18; • Legal matters – Sections 4.3 and 4.4; • Environmental matters and agreements with local communities – Section 19; and • Title and governmental factors – Sections 4.2, 4.4, 19 and 20. Furthermore, the Qualified Persons for Mineral Resources and Mineral Reserves have sought input from in-house Technical Experts/Specialists on aspects of the modifying factors indicated above and for the disciplines outside their expertise. Based on the technical support and advice from the in-house Technical Experts/Specialists who have identified no fatal flaws in the data and information pertaining to their technical disciplines and the operations, the Qualified Persons consider it reasonable to rely upon the information on the Sibanye-Stillwater US PGM Operations provided by Sibanye-Stillwater (the registrant). A list of the in-house Technical Specialists/Experts and their technical areas of competency is summarised in Table 2. Table 2: Technical Experts/Specialists Supporting the Qualified Persons Name Position Area of Competency Academic Qualifications Matt O’Reilly Vice President/General Manager – Stillwater Mine Technical Expert - Mining Bachelor of Science - Mining Engineering Bill Kloth Vice President/General Manager – East Boulder Mine Technical Expert - Mining Bachelor of Science - Mining Engineering Dave Shuck Vice President - Refinery & Laboratory Technical Expert - Refinery Bachelor of Science - Metallurgical Engineering Bruce Parker Operations - Superintendent Metallurgical Complex Technical Expert - Smelting Bachelor of Science – Civil Engineering Perry Finco Maintenance Superintendent Metallurgical Complex Technical Expert - Smelter and Refinery Maintenance Certified Fluid Power Industrial Hydraulic Mechanic CFPIHM #6528, Certified Fluid Power Hydraulic Specialist CFPHS #8727 and Certified Fluid Power Accredited Instructor AFPI #10807 Randy Weimer Corporate Environmental Manager Technical Expert - Environmental and Governmental Affairs Bachelor of Science - Environmental Engineering Jeff Sargent Manager of Projects Technical Expert - Projects High School Diploma, Industry Experience Matt Knight Human Resources Manager Technical Expert - Human Resources Bachelor of Science - Geologic Engineering, Master of Science - Economic Geology Tyler Luxner Chief Engineer Technical Expert - Mine Engineering Bachelor of Science - Mining Engineering Justin Patterson Chief Engineer Technical Expert - Mine Engineering Bachelor of Science - Mining Engineering, Master of Business Administration Matthew Deeks Chief Geologist Technical Expert - Geology Bachelor of Science Dean Brower Chief Geologist Technical Expert - Geology Bachelor of Science Mark Ferster Geotechnical Engineer Technical Expert - Rock Mechanics Bachelor of Science - Geologic Engineering 13 The financial and technical assumptions underlying the Mineral Resources and Mineral Reserves estimations contained in this report are current as at December 31, 2021, which marks the end of the period covered by this report. Such assumptions rely on various factors that may change after the reporting period. For example, in 2022 Sibanye-Stillwater initiated a comprehensive review of the Sibanye-Stillwater operations to reassess its existing budget and LoM plan. Accordingly, the Mineral Resources and Mineral Resources estimations contained in this report may be materially impacted by, among other things, the results of these assessments, including any changes to the underlying financial and technical assumptions. 14 PROPERTY DESCRIPTION Location and Operations Overview The location of Stillwater and East Boulder Mines and the surrounding PGM mining claims near Nye as well as that for the Columbus Metallurgical Complex in Montana, United States of America (US), are indicated in Figure 1 Stillwater and East Boulder Mines are underground mines extracting the J-M Reef and situated approximately 13 miles apart. Figure 1: Location of Sibanye-Stillwater US PGM Operations in Montana The run of mine (RoM) ore from the mines is processed at the integrated surface concentrator plants adjacent to the mine shaft at Stillwater Mine and main access adits at East Boulder Mine. PGM-base metal concentrate from Stillwater and East Boulder Mines is transported to the Columbus Metallurgical 15 Complex, which consists of a smelter, PGM recycling facility, base metal refinery and an analytical laboratory. The smelter processes the PGM-base metal concentrate from the mines and PGM-bearing catalytic converter material from the onsite recycling facility to produce converter matte. The PGM- bearing catalytic converter material is either purchased from or toll processed on behalf of third parties. The converter matte produced is processed at the base metal refinery to recover base metals after which the remaining PGM matte is despatched to third party PGM refineries to recover individual PGMs. Mineral Title Title Overview The General Mining Law of 1872 (May 10, 1872) is the major federal law that authorises and governs prospecting and mining for economic minerals on federal public lands. This law allows for US citizens (including corporate entities) to explore for, discover and purchase these economic minerals and provides for a formalised system of acquiring and protecting mineral title. A Mining Claim is the title that provides a claimant with the right to extract minerals from a specific portion of land. There are two categories of Mining Claims, namely Unpatented and Patented Mining Claims. An Unpatented Mining Claim provides the claimant the right to mine and extract economic minerals (mineral title) for commercial purposes. However, a Patented Mining Claim gives a claimant exclusive title to the minerals and the land (mineral and surface title), with the Federal Government passing the title of the specific portion of land to the claimant, thereby making it private property. Mining Claims can also be permitted either as Lode Claims (for veins or vein-type deposits) that have well- defined boundaries and include other in situ rocks containing valuable mineral deposits or Placer Claims (for all those deposits not subject to Lode Claims). A Mill Site is a form of title that provides surface rights for the establishment of mining-related infrastructure on non-mineralised land. A Tunnel Site, which is similar to servitude, is a form of title that provides a right of way under federal land. It is acquired for access to Lode Mining Claims or to conduct exploration when following a mineral deposit along strike. The more recent Federal Land Policy and Management Act of 1976 (FLPMA) did not amend the General Mining Law of 1872 but affected the documentation and maintenance of all claims. The purpose of the FLPMA is to provide the Bureau of Land Management (BLM) with information on the locations and number of Mining Claims, Mill and Tunnel Sites. Under the FLPMA, claimants are required to record their claims (existing or new claims) with the BLM. Title and Tenure Held The Qualified Persons have considered mineral and surface title provisions of the General Mining Law of 1872 and FLPMA during the assessment of title for Sibanye-Stillwater US PGM Operations. Sibanye- Stillwater (through SMC) holds or leases 1 704 Patented and Unpatented Lode, Placer, Tunnel or Mill Site Claims in the Stillwater, Sweet Grass and Park Counties of south-central Montana which are shown in Figure 2. Table 3 presents a summary of Sibanye-Stillwater's Mining Claims (both leased and held claims)
16 covering the Sibanye-Stillwater US PGM Operations as of December 31, 2021. The 1 704 claims encompass an area of over 24 156 acres in two separate contiguous blocks situated east and west of the Stillwater River and cover the following: • The entirety of the known J-M Reef apex; • Areas to the north for the construction of ventilation and other shafts to the surface from lower levels in the northward-dipping J-M Reef; • The east end of the Stillwater Complex; • East Boulder Mine's access adits and the plant site; • Benbow Decline access and surface portal; • A leased group of claims east of the Stillwater Valley that cover a portion of the Basal Series; and • A leased group of claims west of the Stillwater Valley that cover a portion of the Ultramafic Series. Due to the sheer number of claims held or leased by Sibanye-Stillwater, the Qualified Persons grouped the claims shown in Figure 2 by type and location (county) in Table 3. Table 3 also highlights the Mining Claims covered by the Mouat Basal Zone Lease, Mouat Mountain View Lease, Mouat 'A' Claim Lease and Mouat 'B' Claim Lease Agreements. The Mouat Basal Zone Lease covers 60 claims over the copper and nickel occurrences in the Stillwater Complex located in the Benbow and Stillwater Valley areas. Of the 60 claims, 57 are Lode Claims (33 Patented), one is an Unpatented Placer Claim, one is a Patented Placer Claim and one is a Patented Mill Site Claim. The Mouat Mountain View Lease covers 77 claims of the chromite zones in the Stillwater Valley, of which 70 are Lode Claims (one Patented), two are Unpatented Mill Site Claims, one is an Unpatented Tunnel Site and four are Unpatented Placer Claims. Mouat 'A' Claim Lease covers 28 Lode Claims (nine of which have been issued a First Half Financial Certificate or FHFC), one Unpatented Mill Site Claim and four Placer Claims. The Mouat 'B' Claim Lease covers 145 Lode Claims of which 35 are Patented Claims. Table 3: Summary of Sibanye-Stillwater US PGM Operations Mineral Title and Tenure County Type No. of Claims Area (Acres) Status Expiry Dates Lease Agreement Park Lode Claims 33 622 Unpatented N/A - Sweet Grass Mill Site Claims 163 763 Unpatented N/A - Lode Claims 712 2 001 116 Patented N/A 1 claim subject to the Mouat Basal Zone Lease 10 161 612 Unpatented N/A 17 claims subject to the Mouat Basal Zone Lease Sweet Grass/Park Lode Claims 17 Unpatented N/A Sweet Grass/Stillwater Lode Claims 26 3 Patented N/A 1 claim subject to the Mouat 'B' claim 13 Unpatented N/A 11 claims subject to the Mouat 'B' claim Stillwater Tunnel Site 2 8 Unpatented N/A 1 claim subject to the Mouat Mt View Lease Placer Claims 11 320 9 Unpatented (1 application for patent submitted) N/A 4 claims subject to the Mouat 'A' claim 4 claims subject to the Mouat Mt View Lease 1 claim subject to the Mouat Basal Zone Lease 17 County Type No. of Claims Area (Acres) Status Expiry Dates Lease Agreement 124 2 Patented N/A Mill Site Claims 192 902 191 Unpatented N/A 1 claim subject to the Mouat 'A' claim 2 claims subject to the Mouat Mt View Lease 4 1 Patented N/A 1 claim subject to the Mouat Basal Zone Lease Lode Claims 548 335.3 20 Applied for patent N/A 20 claims subject to the Mouat Mt View Lease 123.3 9 Final Certificate N/A 9 claims subject to the Mouat 'A' claim 721.7 (PGE) 20.7 (Mt View) 632.3 (Basal) 76 Patented N/A 35 claims subject to the Mouat 'B' claim 32 claims subject to the Mouat Basal Zone Lease 1 claim subject to the Mouat Mt View Lease 7 418 444 Unpatented N/A 98 claims subject to the Mouat 'B' claim 19 claims subject to the Mouat 'A' claim 7 claims subject to the Mouat Basal Zone Lease 49 claims subject to the Mouat Mt View Lease Total Number of Claims/Area (acres) 1 704 24 156 Title and Tenure Conditions and Compliance Compliance and maintenance of mineral and surface title can be achieved through payment of maintenance fees or by completing the required Annual Assessment Work. An annual maintenance fee per claim is required to be paid on or before 1 September of the year preceding an assessment year. Placer Claims over 20 acres must pay an additional US$165 per year for each 20 acres or portion thereof. A FHFC can be issued for a claim signifying that the BLM has finished with the paperwork portion of the process and that the claim does not need the annual maintenance fee payment until the patent is issued or the claim is withdrawn from the patent process. Of the 1 704 claims, 1 498 claims are filed on an annual basis with the BLM and County Offices. Sibanye-Stillwater, through the SMC and Sibanye-Stillwater US PGM Operations, also pays the maintenance fee of $165 per claim to the BLM each year to keep the 1 498 claims valid. The Qualified Persons have confirmed that all payments to the BLM are up to date. Annual Assessment Work is note necessary to maintain a claim if the maintenance fees have been paid. When required, the Annual Assessment Work must be performed within the period defined as the Assessment Year and a report submitted for record to the BLM. The assessment work includes, but is not limited to drilling, excavations, driving shafts and tunnels, sampling (geochemical or bulk), road construction on or for the benefit of the Mining Claim, and geological, geochemical and geophysical surveys. For operations involving more than 5 acres, a detailed Plan of Operations must be filed with the appropriate BLM field office. Sibanye-Stillwater has a Plan of Operations for Stillwater and East Boulder 18 Mines which was approved by the US Forest Service (USFS) Custer Gallatin National Forest and the Montana Department of Environmental Quality (MTDEQ). Operating Permits were issued for the operations at Stillwater Mine (Permit #00118) and East Boulder Mine (Permit #00149). All necessary permits and approvals are in place, current, and adequate for existing operations at both Stillwater and East Boulder Mines. Surface Rights and Servitudes The Patented and Unpatented Mill Site and Tunnel Sites held by Sibanye-Stillwater cover the predominant surface infrastructure required for the operations at Stillwater and East Boulder Mines. In addition to the Mill Site and Tunnel Claims, Sibanye-Stillwater owns several land parcels that have been purchased over the years. A number of these parcels are currently used for the operations while others are earmarked for future use. Assessment work is not a requirement for owners of Mill or Tunnel Sites. However, Sibanye-Stillwater is required to file an Annual Notice of Intent to hold each of the sites. The Qualified Persons have confirmed that this condition has been complied with for all the Mill Sites and Tunnel Sites held by Sibanye-Stillwater. Title for the Columbus Metallurgical Complex is based on freehold owned by Sibanye-Stillwater. The building and stack heights at the complex are limited due to the proximity of a light aircraft field but these restrictions do not affect the current and planned mineral beneficiation operations. 19 Figure 2: Sibanye-Stillwater US PGM Operations Mineral Title and Tenure Map
20 Royalties Of the 1 704 Sibanye-Stillwater owned Mining Claims, a total of 898 are subject to the Franco-Nevada and Mouat Royalties as indicated in Table 4. The Franco-Nevada Royalty is a 5% Net Smelter Return (NSR) royalty on all commercially recoverable metals produced from the 813 claims subject to the royalty, and the royalty is then reduced after the application of permissible “onward processing” deductions. The Mouat Royalty is a consequence of the 1984 Mining and Processing Agreement with SMC. The 180 Mouat Royalty claims are subject to a NSR royalty of 0.35%, which is payable to the Mouat family. Table 4: Summary Details of Mining Claims Subject to Royalties County No. of Claims on the J-M Reef Details of Royalties Claims Subject To Royalty Park 34 Claims subject to Franco-Nevada Royalty Sweet Grass 636 Claims subject to Franco-Nevada Royalty Stillwater 85 Claims subject to Mouat Royalty 48 Claims subject to Franco-Nevada Royalty 95 Claims subject to both Mouat Royalty and Franco-Nevada Royalty The Qualified Persons have confirmed that the royalty payments by Sibanye-Stillwater are up to date and the annual royalty amounts paid since 2019 are indicated in Table 5. The differing annual royalty amounts in each of the previous years reflect changes in the key variables considered in the royalty calculations which are metal prices, the number of troy ounces produced and mining claims where the production occurred. Table 5: Details of Historical Royalty Payments to Franco-Nevada and Mouat Counties No. of Claims Royalty Amounts Expensed (US$ Million) FY2019 FY2020 FY2021 Park, Sweet Grass and Stillwater 898 40.9 52.6 59.6 Legal Proceedings and Significant Encumbrances to the Property The Qualified Persons have been advised by Sibanye-Stillwater and the management team at the Sibanye-Stillwater US PGM Operations that there are no material legal proceedings in relation to the Sibanye-Stillwater US PGM Operations discussed in this Technical Report Summary. It should, however, be noted that Sibanye-Stillwater and the Sibanye-Stillwater US PGM Operations may be involved in various non-material legal matters such as employment claims, third party subpoenas and collection matters on an ongoing basis which are not material to the Mineral Resources and Mineral Reserves reported in this Technical Report Summary. The Good Neighbor Agreement is a significant legally binding contract between Sibanye-Stillwater, the Northern Plains Resource Council, Cottonwood Resource Council and Stillwater Protective Association. It formalises engagements between the various stakeholders and provides an innovative framework for the protection of the natural environment while encouraging responsible economic development in the area within which Stillwater and East Boulder Mines are located. Pursuant to these objectives, the Good Neighbor Agreement stipulates clear and enforceable water quality standards, mine traffic 21 restrictions and requirements for the monitoring of and adherence to the permitted traffic volumes and speed limits. The mine plans for Stillwater and East Boulder Mines accommodate the commitments made in the Good Neighbor Agreement to ensure that these commitments are not breached, and historical operations at the mines have honoured these commitments. From the documentation reviewed and the input by the relevant Technical Specialists and Experts, the Qualified Persons could not identify any significant factors or risks with regards to the title permitting, surface ownership, environmental and community factors that would prevent the mining of the J-M Reef and the declaration and disclosure of the Mineral Resources and Mineral Reserves for Stillwater and East Boulder Mines. The Qualified Persons concluded that the Sibanye-Stillwater US PGM Operations comply with all title and environmental permitting requirements of the Federal and State Governments. 22 ACCESSIBILITY, CLIMATE, LOCAL RESOURCES, INFRASTRUCTURE AND PHYSIOGRAPHY Topography and Elevation Stillwater Mine and the Hertzler Tailing Storage Facility Stillwater Mine is located in a steep-sided mountainous valley where elevations exceed 5 000ft above mean sea level (ftamsl). The valley drainage hosts the Stillwater River, which originates in a valley of the Beartooth Mountains within the Custer Gallatin National Forest between Miller Mountain and Wolverine Peak, approximately 25 miles to the south of the Stillwater Mine. Stillwater River generally flows from south to north and to the northeast (Figure 1) after leaving the mountains near the town of Nye, approximately 4.5 miles downstream of Stillwater Mine. It is a tributary to the Yellowstone River, which it joins approximately 36 miles downstream of the Stillwater Mine. The Hertzler Tailings Storage Facility (TSF) is located approximately 6 miles north-northeast of Stillwater Mine (Figure 1) on a relatively flat bluff formed by an old glacial moraine deposit west of the Stillwater River. The Hertzler TSF sits approximately 170ft above the Stillwater River at an elevation of approximately 4 900ftamsl. East Boulder Mine East Boulder Mine is also located in a steep-sided mountainous valley where the elevation exceeds 6 200ft. The valley drainage hosts the East Boulder River, which originates in a valley of the Beartooth Mountains within the Custer Gallatin National Forest between Chrome Mountain and Iron Mountain, approximately 8.5 miles to the south of the East Boulder Mine (Figure 1). The East Boulder River generally flows from south to north. East Boulder Mine is located in the upper third of a roughly 3-mile reach where the river flows west-northwest around Long Mountain before resuming its northward flow to join the Boulder River approximately 14 miles downstream of the East Boulder Mine (Figure 1). Fauna and Flora Vegetation types are similar at Stillwater and East Boulder Mines. The Environmental Impact Statement (EIS) for Stillwater Mine compiled in 1985 identified thirteen vegetation types in the study area, along with water and disturbed areas with no vegetation (MDEQ and USFS, 1985). These vegetation types were described as follows: stony grassland, sagebrush and skunkbush shrubland, drainage bottomland, riparian woodland, ravine aspen-chokecherry, open forest-meadow understory, open forest-rocky understory, Douglas-fir forest, Lodgepole pine forest, sub-alpine forest and cultivated hay land. Timber resources in the mine areas are generally of low commercial value due to the poor quality of the timber and the rugged terrain's limits on harvest operations. Wildlife studies indicate that the mine areas support diverse and abundant wildlife populations, which include bird, mammal, reptile, amphibian and aquatic species. The mine areas also provide winter ranges for elk, mule deer and bighorn sheep, and host moose, black bear, mountain goats and 23 mountain lions. Wildlife habitat types correspond closely to vegetation types in this area. Both the Bald Eagle and American Peregrine Falcon, which were identified as listed species in the 1985 EIS, have been de-listed due to the recovery of their populations. Stillwater and East Boulder Rivers are the principal resources that may be adversely affected by mining operations at Stillwater and East Boulder Mines, but historical and cultural resources are also known to exist within the current and planned mine disturbance areas. The Qualified Persons noted that the river waters are of high quality and, although they have measurable loading of nitrate and dissolved solids from the mining operations with localized, minor periphyton and macroinvertebrate impairment, there has not been evidence of adverse impacts on aquatic or terrestrial wildlife populations. Stillwater and East Boulder Rivers are both considered "substantial fishery resources” and host brown trout, rainbow trout, brook trout and mountain whitefish (MDEQ and USFS, 1985). Both rivers have good insect and periphyton diversities and densities. Access, Towns and Regional Infrastructure The Sibanye-Stillwater US PGM Operations are situated in or near three geographic clusters, namely Stillwater Mine, East Boulder Mine and Columbus Metallurgical Complex, and are accessed local towns through paved and unpaved roads (Figure 1). Stillwater Mine is located near Nye in Stillwater County while East Boulder Mine is located south of Big Timber in Sweet Grass County. Both counties are located in Montana. The Boe Ranch is located northwest of the East Boulder Mine while the Hertzler Tailings Storage Facility (TSF) is located approximately 6 miles north-northeast of Stillwater Mine. Stillwater Mine is located approximately 30 miles southwest of Absarokee and 4 miles south-southwest of Nye. It is accessed from Absarokee by the mainly unpaved County Road 420, which passes the Hertzler Ranch TSF, or via the paved State Highway 78, State Highway 419 and Nye Road (Figure 1). East Boulder Mine is located approximately 25 miles south of Big Timber. It is accessed from Big Timber via the paved State Highway 298 and the unpaved East Boulder Road which is maintained by Sibanye- Stillwater. PGM-base metal concentrate from Stillwater and East Boulder Mines is trucked to the smelter at the Columbus Metallurgical Complex. The town of Columbus is situated approximately 42 miles west of the town of Billings and the two towns are connected by the US Interstate Highway 90. The nearest regional airport is situated in Billings. Climate Stillwater and East Boulder Mines and the Columbus Metallurgical Complex are situated in a region where summer temperatures range from average highs of around 76°F to 82°F to winter average lows of approximately 12°F to 20°F. Extreme highs can reach 91°F and extreme lows can reach -15ºF. East Boulder Mine tends to experience cooler overall temperatures due to its higher elevation when compared to Stillwater Mine. The cold period starts in November and ends in March followed by a warm season starting in April and ending in September. Monthly average precipitation ranges from highs of 3 inches to 4 inches in May to lows of 1 inch to 1.4 inches in late summer (July and August). Rainfall typically
24 increases from March to May and decreases to lows around June through to September, with a short period of increased precipitation occurring around October due to autumn storms. The Qualified Persons noted that, although the mine sites experience a wide range of climatic conditions, the mining operations have often proceeded all year round. Heavy snows, stream flooding or forest fires are the only significant environmental factors affecting site access, but these have not significantly hindered operations since mining commenced at Stillwater and East Boulder Mines. Freezing temperatures in winter and snow can pose adverse operating conditions, although avalanches from the steep mountain slopes have never directly affected operations at the mines. However, snow can affect mine site access, especially to the Benbow Decline at Stillwater Mine which is accessed via a steep dirt road. This decline is roughly at a similar elevation as East Boulder Mine, which is 1 500ft higher than the elevation for the remainder of Stillwater Mine. Snow removal and road maintenance by Sibanye-Stillwater has effectively been used to maintain mine access even in winter storms. The combination of storm conditions and temporary loss of grid power and the need to move a number of personnel from the mine, could potentially pose challenges on occasions. Winter winds can move winter ice on the TSF pond surfaces and cause water storage pond and TSF liner damage, but these operational impacts from climate have been successfully mitigated through routine inspections, facilities maintenance, and installation of liner protection barriers. Infrastructure and Bulk Service Supplies Stillwater and East Boulder Mines and the Columbus Metallurgical Complex have been operational for decades and, as a result, most of the regional and onsite infrastructure required for mining and ore processing is all established at these sites. Electrical power to both Stillwater and East Boulder Mines is provided via the local electrical grid. East Boulder Mine has one 69kV power line owned by Park Electric, which is a local power co-operative that relays power from the Northwestern Energy grid. Stillwater Mine is served by a 100kV powerline and a 50kV power line both of which are owned by Northwestern Energy. The 100kV powerline was recently commissioned to ensure sufficient energy for increased production at Stillwater Mine. Power supply to the Columbus Metallurgical Complex is from Northwestern Energy through a 100kV powerline. Onsite surface infrastructure at the mine complexes includes PGM concentrators, workshops, warehouse, changing facilities, water treatment and storage facilities, offices and TSFs. Tailings deposition at Stillwater Mine has moved from the original Nye TSF to the Hertzler TSF. The TSF at East Boulder Mine is located immediately adjacent to the PGM concentrator. Water supplies to Stillwater and East Boulder Mines are a mix of fresh make-up water from onsite wells and recycled water from the onsite biological and reverse osmosis water treatment facilities. The treatment facilities process water from mine dewatering and process facilities. Bulk water from external sources is not required as the water supply from the onsite sources exceeds the daily water requirements for mining and ore processing. The surplus water is treated further to remove nitrates before it is discharged to the environment. 25 Personnel Sources In-house personnel constitute the bulk of the manpower for Sibanye-Stillwater US PGM Operations, with contractors engaged to execute specific projects when required. Manpower is sourced from different areas of the US and beyond. While preference is given to manpower from local towns and local communities within the Montana State in support of local economic development, there are no restrictions imposed on Sibanye-Stillwater in terms of manpower sourcing. 26 HISTORY Ownership History Prior to the discovery of the J-M Reef in the fall of 1973, Lode Claims were staked by Johns-Manville Corporation (Manville) primarily to cover soil geochemical and geophysical anomalies in the area. The Stillwater Complex-wide contour soil sampling programme completed in 1974 prompted a claim staking blitz as palladium (Pd) and platinum (Pt) were discovered in the J-M Reef. By the end of 1978, Manville controlled 1 022 Lode Claims covering the J-M Reef. In 1979, a Manville subsidiary (Manville Products) entered into a partnership agreement with Chevron USA Inc. (Chevron) to develop the PGMs discovered in the J-M Reef. In 1983, Anaconda Minerals (Anaconda) became a third member of the joint venture but sold its stake to LAC Minerals Ltd (LAC) in 1985. Manville, Chevron and LAC explored and developed the Stillwater property and commenced underground mining in 1986 at Stillwater Mine. By 1989, many shareholding changes had taken place and Manville and Chevron had become the only shareholders in the partnership, with equal shareholding. In 1992, SMC was incorporated followed by the transfer of all Chevron and Manville assets, liabilities and operations at the Stillwater Mine property to SMC on 1 October 1993. As a result, Chevron and Manville each received a 50% ownership interest in the SMC’s stock. In September 1994, SMC redeemed Chevron’s entire 50% ownership. SMC completed an initial public offering in December 1994, which enabled Manville to dispose of a portion of its shares, thereby reducing its ownership percentage to approximately 27%. In August 1995, Manville sold its remaining ownership interest in SMC to institutional investors. Production at East Boulder Mine commenced in 2002. On 23 June 2003, SMC completed a stock purchase transaction with MMC Norilsk Nickel (Norilsk Nickel), whereby a subsidiary of Norilsk Nickel became a majority stockholder of the company. On that date, all the stockholders entered into a Stockholders’ Agreement governing the terms of Norilsk Nickel’s investment in SMC. In December 2010, Norilsk Nickel disposed of its entire ownership interest in SMC through a secondary offering of the SMC shares in the public market. From 2010, SMC operated as a NYSE listed company until May 2017 when it was delisted following its acquisition by Sibanye Gold Limited. An internal restructuring exercise in 2019 resulted in Sibanye Gold Limited becoming a gold-focused subsidiary of Sibanye-Stillwater and the PGM mineral assets in Montana (i.e., the Sibanye-Stillwater US PGM Operations) forming part of Sibanye Platinum (Pty) Limited – the PGM portfolio, which is a wholly owned Sibanye-Stillwater subsidiary. The Sibanye-Stillwater US PGM Operations are currently owned by Sibanye-Stillwater through its wholly owned subsidiaries, Sibanye Platinum (Pty) Limited, Sibanye Platinum International Holdings (Pty) Limited, Thor US HoldCo Incorporated and Stillwater Mining Company (SMC). 27 Previous Exploration and Mine Development Previous Exploration The Stillwater Complex and adjacent areas have been known to host copper (Cu), nickel (Ni) and chromium (Cr) deposits since 1883. However, the complex was first geologically mapped and described in the 1930s by Princeton University Geologists operating out of a base camp in Red Lodge, Montana. Chromite was mined during World War II and processed at a plant on the site of the current Stillwater Mine. Sulphides containing PGMs were discovered in the early 1930s, but significant exploration only started in the 1960s by two separate groups, namely Anaconda Minerals Company (Anaconda) exploring for Cu and Ni, and Manville exploring for PGMs. Exploration by Manville identified the J-M Reef in 1973. This discovery was significant in that it laid the foundation for future exploration for PGMs in this area. Over the years, state agencies, mainly the United States Geological Survey (USGS), carried out significant regional geological survey work (regional surface mapping and gravity, aeromagnetic and topographic surveys) along the Beartooth Mountains which complemented the exploration work by private sector companies. Surface exploration on the eastern part near the Stillwater Mine initiated by Anaconda in 1977 led to the establishment of the Minneapolis Adit between 1979 and 1981. In 1983, SMC, then a partnership between Chevron, Manville and Anaconda, pursued exploration drilling westward and eastward along the J-M Reef from both the surface and underground from the Minneapolis Adit. By 1995, SMC and predecessor firms had drilled 944 diamond drillholes (Table 6) from the surface and from the Frog Pond and West Fork adits over a 28-mile distance in the Stillwater Complex. This work delineated the known 28-mile strike extent of the J-M Reef over which Sibanye-Stillwater holds mineral title. Furthermore, the results of the drilling were used to define the estimated mineralisation in the various blocks (sectors) along the strike length, which are bounded by major geological structures (mainly major faults). Table 6: Historical Surface and Adit Exploration Drillholes Sector Number of Drillholes Tecate 13 Boulder West 28 Boulder East 52 Frog Pond West 104 Frog Pond Adit (in Frog Pond West) 94 Frog Pond East 59 Brass Monkey West 46 Brass Monkey East 83 West Fork West 41 West Fork East 99 West Fork Adit (in West Fork East) 95 Dow 38 Stillwater West 88 Stillwater East 74 Blitz 30 Total Drillholes 944 In 1998, a drillhole located in the Stillwater River Valley at Stillwater Mine intersected the major thrust splay underlying Stillwater Mine, more than 4 000ft below surface. An additional deep drillhole further to
28 the west allowed further delineation of the J-M Reef at depth and of the bounding thrust fault. These deep drillholes also allowed the projection of thrust fault positions that currently define the lower limits of the estimated Mineral Resources and Mineral Reserves in areas near the deep drilling. No surface exploration drilling was carried out between 1995 and 2010 at Stillwater Mine. However, significant surface exploration drilling was carried out between 2010 and 2017 in the easternmost part of the identified J-M Reef in support of the Blitz Project. The Blitz Project is an eastward expansion of the Stillwater Mine footprint, which is now termed the Stillwater East Section. There has not been any surface drilling at East Boulder Mine since 1993. In addition, limited deep drilling to approximately 4 000ft below surface was carried out to explore the depth continuity of the J-M Reef at East Boulder Mine. Most of the post-1995 underground exploration drilling was focused on the brownfield areas within the Stillwater and East Boulder Mine footprints. In general, the ongoing exploration at both mines has entailed driving primary development footwall laterals along with drilling advance probe holes from these laterals to ensure that the J-M Reef is being appropriately followed. This has remained the primary drilling strategy employed to generate the close spaced data required for the evaluation of the J-M Reef and for detailed mine planning at Stillwater and East Boulder Mines. Currently, Mineral Resources across the 28-mile strike length of the J-M Reef are reported within the footprints of Stillwater and East Boulder Mines. In addition to the ongoing infill drilling, surface exploration will be required in the long term to improve the geological confidence in the Mineral Resource area comprising the western part of Stillwater Mine and eastern part of East Boulder Mine. Mine Development Stillwater Mine has been in production since 1986 and was the epicentre for future PGM mining and ore processing operations at the time, whereas production at East Boulder Mine started in 2002. The development of the Stillwater Mine was spurred by a surge in platinum prices due to social and political instability in South Africa, which affected global supplies. Stillwater Mine was originally planned to produce approximately 500 tons of RoM ore per day, but the production target was revised upwards initially to 1 000 tons per day and later to 2 500 tons of RoM ore per day, which was reached in 2001. Production at East Boulder was originally planned at 2 000 tons per day. However, with the development of the East Boulder Mine and a high skills turn-over due to the global competition for mining skills during the worldwide mineral commodity prices boom at the time, production could not be maintained at the steady state levels at both mines. This was exacerbated by labour unrest at the mines in 2007 and the PGM price decline in 2008. Production at the mines was halted in 2008 for a month, and then resumed following organisational restructuring in 2008 and has continued without major interruptions to date. The production history for Stillwater and East Boulder Mines since 2004 is summarised in Table 7, which also indicates that the mines have been on progressive production ramp-up since 2015. The mining footprint at Stillwater Mine has been increasing due to the development of the Stillwater East Section (the Blitz Project). At steady state which will be achieved in 2027, a RoM ore monthly production level of approximately 121 000 tons is planned for Stillwater Mine. Production at East Boulder Mine has also increased progressively since 2008 until 2017 at which point a new steady state target of approximately 29 65 000 tons per month (approximately 785 000 tons per annum) was set. The production increase since 2017 followed the implementation of the Fill the Mill Project which required full utilisation of the previously unused plant capacity (i.e., more than 15 000 tons per month). A combined monthly production output for Stillwater and East Boulder Mines of approximately 186 000 tons is planned from 2027 onwards when both mines operate at steady state. Table 7: Historical Production for Stillwater and East Boulder Mines Year Stillwater Mine East Boulder Mine Total Montana Mines New Mill Feed Tons Pd +Pt Returnable Ounces New Mill Feed Tons Pd +Pt Returnable Ounces New Mill Feed Tons Pd +Pt Returnable Ounces 2021 898 229 346 556 720 953 223 842 1 619 181 570 399 2020 963 533 373 624 679 270 229 442 1 642 802 603 066 2019 886 264 376 395 669 169 217 579 1 555 433 593 974 2018 811 724 364 167 662 638 228 441 1 474 362 592 608 2017 745 240 328 515 643 028 218 676 1 388 267 547 191 2016 715 147 326 976 656 044 218 354 1 371 191 545 330 2015 747 965 319 822 583 452 200 984 1 331 417 520 806 2014 748 680 340 849 515 753 176 928 1 264 333 517 777 2013 800 868 366 061 472 944 157 824 1 273 811 523 885 2012 709 100 377 430 441 103 136 278 1 150 203 513 708 2011 793 826 386 871 416 160 131 001 1 209 986 517 872 2010 780 436 351 702 400 411 133 387 1 180 847 485 088 2009 777 151 393 837 407 393 136 091 1 184 544 529 928 2008 767 608 349 365 438 755 149 526 1 206 363 498 891 2007 714 680 359 269 528 962 178 204 1 243 642 537 473 2006 800 996 409 389 549 665 191 162 1 350 661 600 551 2005 790 020 381 054 495 778 172 495 1 285 799 553 549 2004 786 580 404 966 483 281 164 221 1 269 861 569 187 Plant, Property and Equipment Sibanye-Stillwater owns extensive long-term assets at Stillwater and East Boulder Mines and the Columbus Metallurgical Complex. These assets include property, plants and equipment most of which have been inherited from the previous owners and the remainder acquired after acquisition in 2017. Concentrators, smelter and base metal refinery (the plants) and surface infrastructure have significantly longer useful lives than equipment. Appropriate sustaining capital funding for maintenance and upgrades of major units for each of property, plants and equipment has been included in annual budgets to prolong their useful lives. A summary description highlighting the age and physical condition of the major units of property, plants and equipment at Stillwater and East Boulder Mines and the Columbus Metallurgical Complex is provided in Table 8. 30 Table 8: Summary Description of Plant, Property and Equipment for the Sibanye-Stillwater US PGM Operations Site Description Age Profile Physical Condition Net Book Value ($ million) Category Major Units Period Acquired/Built Range Useful Life (Years) Average Age (Years) Average Utilisation (%) Description Stillwater Mine Underground Equipment Load Haul Dumpers (LHDs), Dump Trucks, Utility Vehicles (UVs), Drill Rigs 1998-2021 1-25 8 28 Average to Good, Operating 72.6 Underground Infrastructure Workshops, Offices, Services, Rail, Ore passes, 1985-2021 1-50 18 50 Average to Good, Operating 1.8 Underground Development Shaft, Surface Portals, Declines, Ramps, Vent Shafts 1985-2021 30-50 19 100 Average, Operating 373.5 Surface Equipment UVs 1992-2002 1-25 23 20 Average, Operating 1.1 Surface Buildings & Plant Offices, Core Storage Facilities, Concentrator (Conveyor belts, crusher, mills, flotation circuits, filter press, contrate handling facilities) 1985-2014 1-40 30 90-100 Poor to Average, mill being rebuilt 100.4 Total 549.4 East Boulder Mine Underground Equipment LHDs, Dump Trucks, UVs, Drill Rigs 2000-2021 1-25 16 18 Poor to Average, Operating 7.4 Underground Infrastructure Workshops, Offices, Services, Rail, Ore passes, 2000-2021 1-50 16 50 Average, Operating 0.2 Underground Development Shaft, Surface Portals, Declines, Ramps, Vent Shafts 2000-2021 30-50 11 100 Average, Operating 150.5 Surface Equipment UVs 1996-2021 1-25 18 25 Average, Operating 0.2 Surface Buildings & Plant Offices, Core Storage Facilities, Concentrator (Conveyor belts, crusher, mills, flotation circuits, filter press, contrate handling facilities) 2001-2021 1-40 20 75-100 Average, Operating 29.5 Total 187.8 Columbus & Columbus Met Complex Surface Equipment 1996-2021 1-30 20 40 Poor to Average, Operating 0.6 Surface Buildings & Plants Offices, Laboratory, Smelter (furnaces, drying, converting, granulation, bagging and scrubbing facilities), BMR (mills, leaching, drying, filtration, electrowinning circuits), loading facilities 1990-2021 1-40 25 50 Poor to Good, Operating 81.7 Total 82.3 Grand Total 819.5 31 ADJACENT PROPERTIES Sibanye-Stillwater’s mineral title covers the entire known strike length of the J-M Reef of approximately 28 miles. The J-M Reef is currently the only PGM-bearing layer in the Stillwater Complex that can be economically exploited at the current and expected economic conditions. As a result, only the geological and mining information generated by Sibanye- Stillwater and predecessor companies within the areas for which Sibanye-Stillwater holds title is of relevance to the Mineral Resources and Mineral Reserves for Stillwater and East Boulder Mines. Accordingly, there is no relevant adjacent property information to be discussed in this Technical Report Summary.
32 GEOLOGICAL SETTING, MINERALISATION AND DEPOSIT Regional Geology The geology of the Stillwater Complex is fairly well-understood from state (US Geological Survey or USGS) and private sector companies driven regional and local exploration and mining as well as from academic research spanning decades. The following summary description of regional geology and geological structure of the Stillwater Complex is based on overviews provided by Page and Zientek (1985), Zientek et al. (1985), Boudreau (1999) and McCallum (2002). The Stillwater Complex is a large layered igneous complex (Figure 3) resulting from magma intrusion through regional transverse faults into highly deformed Archaean sedimentary rocks at approximately 2.7 billion years ago (Ga). Intruded as a layered igneous complex with shallow dipping layers in a lopolithic form, the Stillwater Complex was exposed and partially eroded before burial by extensive sedimentary cover following substantial marine and continental sedimentation. Post burial, there were repeated phases of deformation of the Stillwater Complex and the underlying and overlying sedimentary rocks, the most notable being the Laramide Orogeny. The Laramide Orogeny, which started in the Late Cretaceous and lasted until the Early Tertiary, involved northward verging thrusting (Horseman Thrust Fault System) that resulted in the 20 000ft of uplift (Beartooth Uplift; Figure 4 and Figure 5) and erosion, which exposed the small part of the Stillwater Complex mapped in the Beartooth Mountains. The exposed portion of the complex has been the exploration and mining target for chromite and PGMs since the 1960s. However, the flat-lying part of the Stillwater Complex occurs at significant depth below surface, which makes the exploitation of the J-M Reef in this part of the complex uneconomic. The magma intrusion and emplacement relating to the Stillwater Complex were accompanied by fractionation and accumulation of magmatic crystals that gave rise to the conspicuous magmatic layering observed in the complex. The magmatic layering is reflected by the changes in mineralogy, mode, grain size and texture across the stratigraphic profile of the complex. However, the overall texture of the lithological units in the Stillwater Complex is typified by subhedral to euhedral cumulate grains in a framework of post- cumulus interstitial material including oikocrysts. The mineralogical, modal, grain size and textural variations formed the basis for subdividing the Stillwater Complex into five major series (from bottom upwards) as follows: the Basal Series, Ultramafic Series, Lower Banded Series, Middle Banded Series and Upper Banded Series (Figure 6; McCallum, 2002). The Ultramafic Series (UMS) is further subdivided into the Bronzitite Zone and Peridotite Zone. The Lower Banded Series hosts the J-M Reef targeted at Stillwater and East Boulder Mines. 33 Figure 3: Regional Geology of the Stillwater Complex and Surrounds (Source: Montana Bureau of Mines and Geology) 34 Figure 4: South to North Sections Through Stillwater Mine Showing Subsurface Geology (Source: Montana Bureau of Mines and Geology) Figure 5: A Schematic Section through Stillwater Mine Depicting the Horseman Thrust System The steep dipping nature of the lithological layers in the exposed part of the Stillwater Complex is due to uplift and tilting associated with the Laramide Orogeny. Faults and dykes are the most common geological structures. Most of the regional faults affecting the 35 Stillwater Complex have been ascribed to the Laramide Orogeny and are grouped according to trends as follows: • Northwest to southeast striking thrust faults; • East to west striking south dipping steep reverse faults; and • East to west trending vertical faults. These are also the most common fault and dyke trends observed at Stillwater and East Boulder Mines. Numerous diabase and felsic dykes that cut and offset the J-M Reef at the mines are known from surface mapping, underground drilling and mining. These dykes dilate the J-M Reef, but do not destroy the PGM mineralisation and have limited (up to 30ft) contact alteration zones along which poor ground conditions are common. However, these ground conditions do not present significant obstacles to mining and are dealt with using established support procedures. Local and Property Geology Local Stratigraphy The local stratigraphy at Stillwater and East Boulder Mines resembles the regional stratigraphic sequence of the Stillwater Complex indicated in Figure 6. Much of the area covered by the Sibanye-Stillwater held or leased Mining Claims is underlain by the Lower Banded Series that hosts the J-M Reef and, to a lesser extent, the Ultramafic and Middle Banded Series.
36 Figure 6: General Stratigraphy of the Stillwater Complex (Source: Boudreau, 1999) The Lower Banded Series consists of norite and gabbronorite units and minor olivine-bearing cumulates that host the J-M Reef. The series has been subdivided into Norite I (N-I), Gabbro- norite-I (GN-I), Olivine-bearing-I (OB-I), Norite-II (N-II), Gabbronorite-II (GN-II) and Olivine- bearing-II (OB-II) zones. While the J-M Reef is generally confined to the OB-I (troctolite) zone, it is not restricted to a particular stratigraphic position within this zone. The contact between the Lower Banded Series and the underlying Bronzitite Zone of the Ultramafic Series has been mapped over much of the Stillwater Complex. 37 The Bronzitite Zone is relatively uniform and consists of bronzitite and forms the upper part of the 2 756ft to 6 562ft thick Ultramafic Series. The Peridotite Zone constitutes the bottom part of the Ultramafic Series and is characterised by cyclic peridotite, harzburgite and bronzitite units. This zone overlies a uniform, laterally extensive bronzitite cumulate layer, dominates the Basal Series and is underlain by norite units and subordinate anorthosite, gabbro and peridotite units. Layers of massive and disseminated chromite – referred to by the letters of the alphabet A to K from bottom upwards – occur in the peridotite member of the cyclic units (Figure 6). The thickness of chromitite layers range from a few inches to 3ft, and only layers G and H have been exploited at Mountain View by other parties. Sibanye-Stillwater targets only the PGM and associated base metal mineralisation in the J-M Reef and, as a result, the chromitite mineralisation in the Stillwater Complex will not be discussed further in this Technical Report Summary. The Middle Banded Series overlying the Lower Banded Series consists of anorthosite, olivine gabbro and troctolite units, which constitute the Anorthosite Zones I and II (AN-I and AN-II), which are separated by OB-III and OB-IV zones. A second but low-grade PGM-bearing zone (referred to as the Picket Pin deposit) occurs in the upper part of AN-II and close to the contact with the Upper Banded Series, approximately 9 850ft above the J-M Reef. The Upper Banded Series consists of gabbronorite units and minor troctolite and norite units making up the OB-V and GN-III subzones. The Picket Pin deposit is traceable at a similar stratigraphic position over 14 miles and consists of podiform and lenticular concentrations of sulphide minerals in anorthosite. Due to its low-grade nature, it has not been mined but is the subject of exploration and evaluation by other parties in areas adjacent to Sibanye-Stillwater mineral tenement and is therefore not discussed further in this Technical Report Summary. J-M Reef Mineralisation 8.2.2.1 Mineralisation Style and Geological Controls The J-M Reef exploited at Stillwater and East Boulder Mines is a world class primary magmatic stratiform PGM deposit occurring mainly within a troctolite (OB-I zone) of the Lower Banded Series. It has retained most of its primary magmatic characteristics, particularly its broad lateral continuity, very coarse textures and consistent ore and silicate mineral abundances. A combination of visible disseminated copper-nickel sulphide minerals (0.25% to 3% modal abundances) within a complex cumulate of silicate minerals, consistent stratigraphic location (OB-I zone) and lithological sequences (footwall, reef and hangingwall) as well as reliable lithological markers facilitate the visual identification and delineation of the J-M Reef for sampling purposes. Sampling and laboratory analysis provide the definitive data required to confirm the presence of the J-M Reef and to determine its PGM tenor. Historically, reef intersections that did not have visible sulphide minerals were not sampled but were assigned a zero grade. However, current protocols require the sampling of all reef intersections irrespective of the sulphide mineral abundance. The ore mineralogy of the J-M Reef is dominated by disseminated chalcopyrite, pyrrhotite and pentlandite, with minor pyrite, moncheite, cooperite, braggite, kotulskite, Pt-Fe alloy and various arsenides within a complex cumulate of olivine, plagioclase, bronzite and augite. Pd is the dominant PGM in the J-M Reef and occurs primarily (80%) as a solid-solution 38 in pentlandite as well as in sulphides (15%) and moncheite (5%). Pt occurs primarily (67%) in sulphides, as a metal alloy (isoferroplatinum, 25%) and in moncheite (telluride mineral, 8%). 8.2.2.2 Length and Width Sibanye-Stillwater holds title over the entire 28-mile strike length of the J-M Reef. For evaluation purposes, the J-M Reef is defined as the Pd-Pt rich stratigraphic interval mainly occurring within the OB-I zone and characterised by a variable thickness ranging from 3ft to 9ft (average 6ft) and average combined Pd and Pt (2E) grades of 0.6oz per ton (opt) to 0.8opt. Locally, it forms keel-shaped footwall zones, which transgress the footwall mafic rocks, commonly reaching thicknesses of 18ft and greater. Of the two PGMs, Pd is the most significant resulting in average in situ Pd:Pt ratio of 3.4:1 and 3.6:1 for Stillwater and East Boulder Mines, respectively. Ongoing metallurgical accounting has determined Pd:Pt ratio of 3.5:1 and 3.6:1 for Stillwater and East Boulder Mines, respectively, which are used for all evaluations. Other associated PGMs (e.g., Rh, Ir, Ru and Os), Au and base metals (Cu and Ni) occur in low abundances and are generally not evaluated. In general, the stratigraphy of the J-M Reef is relatively consistent and is fairly well-understood from the extensive diamond core drilling and mining undertaken at Stillwater and East Boulder Mines. It consists of a sequence comprising the Footwall Zone, J-M Reef and Hangingwall Zone. The J-M Reef consists of mineralised troctolite or olivine-bearing rock units. The immediate Footwall Zone underlying the reef consists of bronzitite, norite and gabbro- norite units whereas the Hangingwall Zone consists of anorthosite, norite, gabbro-norite and troctolite units. Unlike the Hangingwall Zone, which is present in most places, the footwall Zone is not always present. Figure 7 shows the stratigraphic sequence and two typical downhole Pd-Pt grade profiles of the J-M Reef intersected by drillhole DDH41276 at Stillwater Mine and DDH2017-0064 at East Boulder Mine. 39 Figure 7: Typical Stratigraphic Sequence and Pd-Pt Grade Profiles of the J-M Reef The basal contact of the J-M Reef is conformable, but irregular, with the irregularity depicted by local depressions and highs in the plane of the reef. It is also common for the hangingwall contact to cut across lithological contacts. Geological personnel at the mines employ textural changes in the footwall, J-M Reef and hangingwall lithologies to guide the visual delineation of the J-M Reef for sampling purposes. The textures include rounded cumulus olivine, oikocrysts and fine to medium grained intercumulus pyroxene, as well as micro- rhythmic layering. The textures for hangingwall lithologies differ from the J-M Reef textures which are typified by pegmatoidal pyroxene, adcumulus pyroxene surrounding anhedral olivine and coarse grained intercumulus pyroxene. Furthermore, the hangingwall textural contact is always present and identifiable along the strike lengths of the J-M Reef and is, therefore, the most reliable marker. The reappearance of olivine cumulates or sulphide minerals above GN-I usually marks the lower boundary of the reef package. Accordingly, drilling information should facilitate accurate delineation of the J-M Reef in space and it is
40 unlikely that the reef will be incorrectly identified during logging or inaccurately correlated during modelling. A high thickness and grade variability over short ranges (stope level) characterises the J-M Reef and this is more pronounced at Stillwater Mine (West Section) where the PGM mineralisation may occur as a unique mixture of "ballrooms", low-grade and normal J-M Reef mineralisation over short intervals. Ballrooms describe localised areas of thickened J-M Reef at Stillwater Mine where the Basal, Main and Upper Zones of the reef coalesce. The ballrooms are important to the economics of the J-M Reef as they contain significant (anomalous) reef tons and Pd-Pt metal content, but their location and size are unpredictable. In general, wider than normal J-M Reef intercepts from initial sparsely to moderately spaced drillholes are interpreted as indicative of the existence of ballrooms at Stillwater Mine. However, ballrooms can only be definitively identified through underground definition drilling at 50ft drillhole spacing whereas the actual ballroom dimensions can only be ascertained during mining. 8.2.2.3 J-M Reef Continuity The attitude of the J-M Reef is variable and characterised by moderate to sub- vertical/vertical dips towards the north and northeast. At Stillwater Mine, the dip of the J-M Reef northwards varies from approximately vertical in the eastern part to approximately 62° in the central part and between 45° and 50° in the Upper West sector of the mine. However, at East Boulder Mine, the dip is less variable and is on average 50° towards northeast. Being a magmatic reef type deposit, the J-M Reef package is laterally continuous and located at a consistent stratigraphic level in the Stillwater Complex. Accordingly, the presence and relative location of the J-M Reef at a mine scale can be predicted accurately even from sparse drillhole information, such as that generated from surface drilling. The J-M Reef has been explored from surface outcrop to depths of approximately 4 000ft below surface mainly through diamond core drilling. The down dip continuity of the J-M Reef is interpreted to have been terminated by thrust faults relating to the Horseman Thrust Fault System. These faults have been intersected by deep drillholes at Stillwater Mine. These drillhole intersections of the faults have been used to constrain the depth limit of the Mineral Resources and Mineral Reserves reported for Stillwater Mine. However, similar deep drilling at East Boulder Mine has not intersected these faults and the location of the faults is currently unknown. Available deep drilling information at East Boulder Mine suggests that the elevation of these thrust faults decreases towards the west from Stillwater Mine. Therefore, there may be potential for generating additional Mineral Resources at depth at East Boulder Mine. Results of geostatistical analysis also confirm the continuity of the Pd-Pt grades in the J-M Reef. At a local scale, the geological continuity of the J-M Reef is interrupted by geological structures such as mafic and felsic dykes and sills, and faults. There are clear lithological and textural differences between the J-M Reef and the dykes and sills, which facilitate the identification of these intrusives in drillcores and during mining. Locally, the sill-like behaviour of the intrusive geological structures resulted in reef splitting, but this has no material negative impact to the mining operations. 41 8.2.2.4 J-M Reef Variability and Implications for Evaluation The combined effect of dip, thickness and grade variability affects the manner in which the J-M Reef is evaluated. Comprehensive geological and geostatistical studies of the J-M Reef completed over the years undertaken in support of Mineral Resource estimation have confirmed that the Pd-Pt mineralisation is broadly continuous and predictable throughout the J-M Reef, except when the continuity is interrupted by faults, dykes and sills. However, these studies and mining experience have also identified high variability of the reef at a micro (stope) level. Trends in the thickness and grade variability also show a direct link between this localised variability and changes in local reef stratigraphy (Figure 8). The cumulative knowledge accumulated over the years has been used to delineate blocks of similar grade and thick signatures and stratigraphy. This knowledge has also been used to establish a yield (ore ton per ft of development), which was valuable metric used in historical evaluations until FY2020. Some of these blocks are bound by major geological features. Geological blocks delineated at Stillwater Mine are the following: Dow Lower, Dow Upper, Block 1 Lower West, Block 1 Lower East, Block 1 Upper, Block 2, Block 3, Block 6 Lower, Block 6 Upper, Block 7, Block 8, Blitz West and Blitz (Figure 9). Reef intersections at East Boulder Mine show less localised variability and, as a result, six broad geological blocks have been delineated, namely the lower grade Frog Pond East (FPE), and Brass Monkey East (BME) and Brass Monkey West (BMW), and the higher-grade Frog Pond West (FPW), Boulder East (BOE) and Boulder West (BOW) shown in Figure 10. The J-M Reef is evaluated using these geological blocks. At the Stillwater Mine, some of the geological blocks are grouped into geological domains where adjacent blocks have a similar reef orientation. Block 1 Lower West, Block 1 Lower East, Block 1 Upper, and Block 2 are grouped into the Upper West East (UWE) domain. Block 3 and Block 6 Lower are grouped into the Off-Shaft West Lower (OSWL) domain. Block 7 is the Off-Shaft East-West (OSEW) domain. Block 8 is the Off-Shaft East-East (OSEE) domain. At East Boulder Mine, the blocks and the domains are the same. Figure 8: West to East Schematic Section Showing Variability in Stratigraphy and Impact on the J-M Reef at Stillwater Mine 42 Figure 9: West to East Section Showing Geological Blocks of the J-M Reef at Stillwater Mine 43 Figure 10: West to East Section Showing Geological Blocks of the J-M Reef at East Boulder Mine
44 EXPLORATION Data Acquisition Overview Exploration work completed in the Stillwater Complex, which led to the discovery of the J-M Reef in the 1970s and generated the geological data used to prepare the Mineral Resource estimates for Stillwater and East Boulder Mines, spans decades. Early exploration work mapped the entire outcrop of the J-M Reef of approximately 28 miles in the Beartooth Mountains and identified major geological structures disrupting the continuity of the reef. Much of this early exploration was driven by the USGS and academic research institutions, and the geological information generated is publicly available, for instance, from the following organisations and their websites: Montana State Library website (http://geoinfo.msl.mt.gov/msdi.as), Montana Bureau of Mines and Geology (https://www.mbmg.mtech.edu/gmr/gmr.asp) and USGS (https://www.usgs.gov). Additional information was generated from exploration and mining activities completed by SMC and predecessor companies. The historical exploration employed a variety of exploration techniques, namely aeromagnetic, gravity and soil geochemical surveys, surface mapping, excavation of adits and sampling, diamond core drilling and drillcore sampling. Of the exploration techniques, diamond core drilling has produced the most relevant data used for Mineral Resource estimation. It is also the dominant sampling technique for ongoing exploration and evaluation, and all mineralised drillcores are sampled and analysed at the laboratory. Accordingly, the Qualified Persons have focused on this relevant part of data collection while presenting overviews of the historical gravity, aeromagnetic and topographic surveys carried out within the Stillwater Complex by the USGS. Gravity Surveys Kleinkopf (1985) interpreted the Bouger gravity-anomaly map of the historical gravity survey data collected mainly by the USGS and US Defence Mapping Agency. The gravity data was based on helicopter and ground surveys, with an estimated precision of 2mGal. From the interpretation, it was noted that the Stillwater Complex occurs as a high-gradient gravity zone in the Beartooth Mountains, which is defined by -175mGal to -155mGal contours. This work facilitated the mapping of the Stillwater Complex and provided indications of the orientation at depth of the uplifted part of the complex. Aeromagnetic Surveys Blakely and Zientek (1985) described the results of the aeromagnetic survey completed by Anaconda in 1978 to map the extent of the uplifted part of the Stillwater Complex along the Beartooth Mountains, the main magnetic lithological units and geological structures. The aeromagnetic survey campaign was based on 853ft helicopter flight line spacing at a mean terrain clearance of 249ft. Mafic and ultramafic lithological units of the Stillwater Complex associated with magnetic anomalies of between 50nT to 300nT were delineated. The magnetic survey data which facilitated the mapping of the Stillwater Complex is available at the USGS in the form of digital maps. 45 Topographic Surveys For previous Mineral Resource evaluations until 2019, historical LandSat topographic survey data acquired by the USGS was used. However, the USGS generated high-resolution topographic data of the area in 2019, which was acquired by Sibanye-Stillwater for use at Stillwater and East Boulder Mines. This data is now being used for Mineral Resource estimation at Stillwater and East Boulder Mines. Exploration and Mineral Resource Evaluation Drilling Drilling The Mineral Resource estimates for Stillwater and East Boulder Mines contained in this Technical Report Summary are based on an extensive drillhole database consisting of underground and surface diamond core drillhole data. The combination of localised grade and thickness variability and subvertical to vertical dips of the J-M Reef and the rugged topography of the Beartooth Mountains has influenced the drilling strategy and evaluation approaches used at the mines. The diamond core drilling is based on the standard tube BQ-size drill bit to recover 1.4-inch diameter drill cores. The Qualified Persons are satisfied with the BQ drill bit size used as this is appropriate for the style of the mineralisation and is widely used in the PGM sector. Most of the underground and surface drillholes are inclined but not ‘oriented’ as this is not necessary given the style of the mineralisation, short drilling lengths and overall attitude of the J-M Reef which is well-understood. Surface drilling is only completed in areas where topography allows access and drilling activities can be safely completed. Owing to the broad lateral geological continuity and occurrence at a consistent stratigraphic location of the J-M Reef, the reef’s presence and relative location can be predicted relatively accurately from moderately spaced surface drillhole data. The overall spacing utilised for the surface drillholes ranges from approximately 1 000ft to 2 000ft. The surface drillhole data is sufficient to confirm the presence and to determine the main characteristics of the reef critical for evaluation, namely thickness, grade and domain. Accordingly, surface drilling information generates the primary information that is utilised to plan underground access drives to be utilised for follow up underground drilling. Geological information generated by public institutions, SMC and predecessor companies during the early exploration programmes was utilised for the planning of the 944 diamond core holes drilled between 1969 and 1995 from surface over the 28-mile strike of the J-M Reef and from the adits at the Frog Pond and West Fork. The historical exploration drilling data was also utilised to determine the depth continuity of the J-M Reef. The historical drillholes intersected the Horseman Thrust Fault, which is the regional fault that forms the lower boundary on the estimated Mineral Resources at Stillwater Mine. Surface drilling ceased from 1995 until 2010 but was resumed at the Stillwater East (Blitz) Section of Stillwater Mine until 2017. At East Boulder Mine, underground drilling has been ongoing since 2002. There has not been any surface drilling at both mines under Sibanye-Stillwater ownership since 2017. The localised grade and thickness variability necessitates follow up close spaced underground drilling at 50ft spaced drill stations. Underground drilling is mainly aimed at increasing the confidence in the geological knowledge to a level that permits the estimation of Measured Mineral Resources and that generates the requisite data for detailed mine planning. The underground drill stations are situated in 46 footwall lateral drifts, which are spaced 300ft to 400ft vertically and established approximately 100ft to 150ft from the J-M Reef plane. At each drill station, a single radial drillhole fan is established to drill through the J-M Reef and perpendicular to its strike (Figure 11). This is achieved through drilling a sub- horizontal hole perpendicular to the reef plane, four up-holes and two down-holes. In addition, probe and off-angle drillholes are drilled when required to investigate local geological, geotechnical or groundwater conditions. Additional underground drillhole information is generated through development drilling. Figure 12 and Figure 13 are drillhole layouts for Stillwater and East Boulder Mines, respectively. These layouts show points at which the drillholes intersect the J-M Reef (pierce points) and not actual drillhole collar positions. The current drillhole database for Stillwater Mine contains data relating 47 312 drillholes (11.4 million feet of drilling) whereas that for East Boulder Mine contains data relating to11 489 drillholes (3.5 million feet of drilling). Figure 11: Underground Definition Diamond Drilling Pattern The Qualified Persons are satisfied with the drilling strategy employed as well as the density and distribution of drillhole data generated at Stillwater and East Boulder Mines. While the intensity of the 47 underground diamond drilling is remarkably high for PGM reef evaluation, generating between 0.5 million feet and one million feet of drillcore per annum at Stillwater and East Boulder Mines combined, this is necessary for the accurate definition of the reef especially in the areas earmarked for mining in the short to medium terms in light of the localised grade and thickness variability. Furthermore, this drilling provides the close spaced data required to support the geological modelling and estimation approaches employed at Stillwater and East Boulder Mines. Extensive underground drilling is currently taking place in the Stillwater East (Blitz) Section owing to the requirement to generate Measured Mineral Reserves for the production ramp-up at Stillwater Mine, resulting in Stillwater Mine accounting for more than 80% of the 0.5 million feet and one million feet of drillcore drilling per annum. The Qualified Persons are satisfied with the drilling management practices employed. Standard procedures are available for diamond core drilling management, with internal sign-off procedures and supervisory structures in place specifying areas of responsibility and oversight. The drillcore recovered is sequentially placed in core trays according to drilling depth, and the trays are transported by the drilling crews to surface drillcore processing and storage facilities once drilling has been completed. Geologists are responsible for drilling management and for ensuring that the drillers maintain the integrity of drillcores during drilling and the transportation of core trays to the core logging facilities. The drilling management protocols require high standards of drilling and cleanliness as well as high core recoveries, with any significant core loss resulting from the driller’s negligence necessitating a re-drill of the hole. All drillcores recovered are cleaned and placed in core trays, which are sealed and transported from drill sites to the core logging facilities from where core accounting, depth reconciliation, core depth marking, core photography, core logging and core sampling are undertaken by Geologists. Core recoveries are determined for each drill run on a pull-by-pull basis. Cases of re-drilling holes are infrequent, and the few cases are due to bad ground conditions affecting core recovery, which makes the re-drills unnecessary. All drillhole collars are surveyed but drillhole traverse surveys are completed on selected drillholes to assess and quantify any deviation. All drillholes are logged by experienced geological personnel. Grade estimation is based entirely on surface and underground drillhole data. Typically, the drillhole data includes drillhole collar and traverse surveys, sample lengths, lithological descriptions, reef delimitations, reef facies (domain) descriptions and grades. The Qualified Persons are satisfied that this data is of sufficient quality to be relied upon, having been subjected to rigorous internal validations.
48 Figure 12: Drillhole Layout for Stillwater Mine 49 Figure 13: Drillhole Layout for East Boulder Mine 50 Core Logging and Reef Delineation All drillcores are logged and sampled by experienced Geologists who are also responsible for the sampling of mineralised reef intersections. The Geologists perform core processing, marking, logging and sampling for surface and underground drillholes. A manual is in place to standardise the core logging and sampling processes. The Geologists at Stillwater and East Boulder Mines are trained to identify local stratigraphy, lithological units and the J-M Reef. Upon delivery of the core trays at the core storage facilities, the Geologists inspect the core trays and check the information on the driller’s log sheets against the original drilling proposal, and this information includes the drillhole identification number, inclination and total length. Core logging is undertaken for the entire rock core recovered and involves the capture of key geological and geotechnical attributes of the rocks as well as geological structures observed. It focuses on the identification and demarcation of reef intersections for sampling and the immediate footwall and hangingwall lithologies. In addition, occurrences of sulphide minerals are noted by way of marking with a yellow lumber crayon. Elevated sulphide mineral abundances are denoted with bold lines and trace sulphide mineralisation is marked using a dashed line. The Geologists estimate the proportion of sulphide mineral as a percentage of the total sample volume. Trace sulphide mineralisation is referred to using the following terminology: trace minus (barely visible pyrite); trace (fleck or two of chalcopyrite, pyrrhotite or pentlandite); and trace plus (few sulphides flecks up to 0.25% of sample volume). Logging is completed on paper log sheets, but the log details are captured manually in the Core Logger system for onward electronic transmission into the Ore QMS database. After electronic capture, the paper logs are kept until the information in the Ore QMS is fully validated and archived on the central Information Technology (IT) server. Core recovery data is captured during geotechnical logging and available data indicates achievement of over 96% core recoveries by the drillers (Table 9). As PGM minerals are not identifiable visually, their presence is inferred from their association with copper- nickel sulphide minerals. All visually identified mineralised intersections in drillcores are sampled and the samples collected are analysed at the in-house laboratory situated at the Columbus Metallurgical Complex. After the delineation of the J-M Reef, sample intervals are marked in 0.5ft to 3ft segments and the marking is extended to 3ft and 1ft into the footwall and hangingwall of the mineralised intersection. The Qualified Persons are satisfied with the core logging and reef delineation carried out at Stillwater and East Boulder Mines. These activities are performed by trained Geologists who are supervised by experienced Geologists. The use of a common manual for core logging and reef delineation and marking ensures consistent core logging and sampling at Stillwater Mine and Easter Boulder Mine, which facilitates the integration of the datasets during modelling. Survey Data The NAD83 State Plane is used for all surface surveys whereas a mine grid, which is based on the NAD27 State Plane rotated by 20º clockwise for alignment with the generally east to west strike direction of the J-M Reef, is used for all underground surveys at Stillwater and East Boulder Mines. There is a conversion in place to work between these two coordinate systems. 51 In 2019, Sibanye-Stillwater US PGM Operations acquired recent high-resolution topographic data from the United States Geological Survey. The airborne LIDAR survey data was processed to yield topographic contours with 5ft vertical intervals. The airborne LIDAR survey data is more accurate than the LandSat survey data used for previous Mineral Resource evaluations. As a result, the processed topographic data is now being used to generate the topographic wireframe used as the upper constraint for geological modelling and Mineral Resource reporting. The mines survey the collar coordinates, azimuth and inclination of each hole, and these surveys are completed by the Mine Surveyors. Initial collar locations of surface drillholes are established by GPS. After drilling, a total station is used to survey the drillhole collar, azimuth and inclination. Surveying of underground diamond drillholes consists of placing a rod into the drill collar to a depth of 2ft and collecting survey points at the collar and endpoint of the rod. From this data, the information is processed and stored in the database showing drillhole collar co-ordinates, azimuth and inclination. Drillhole traverse (downhole) surveys are completed on selected drillholes to assess and quantify any deviation. Experience at the mines has shown that downhole surveys on definition holes do not significantly improve the modelling of the J-M Reef and are unnecessary for as long as the holes are surveyed at the collar for azimuth and inclination. Furthermore, available data has shown up to 5ft of deviation on 300ft to 400ft long holes and up to 10ft on the 600ft to 650ft probe holes. As a result, the mines minimise the drilling of definition drillholes obliquely given that even 5ft of deviation can become exaggerated with off-section drilling. At Stillwater Mine, the downhole surveys are completed for probe holes designed to intersect the J-M Reef ahead of the footwall lateral advance, probe holes drilled straight ahead to check for ground conditions for development advance and the few holes drilled oblique to the J-M Reef plane from a single location to cover a wide area. The surveys are completed using a magnetic multi-shot downhole survey tool (isCompass) with accuracies of ±0.15º and ±0.35º on inclination and azimuth measurements, respectively. At East Boulder Mine, down hole surveys are completed on select probe holes. These surveys are completed using a Reflex EZ-TRAC tool that has an accuracy of ±0.25º on inclination and ±0.35º on azimuth. In poor ground conditions, where the downhole survey tool could be at risk, the mines will survey only the first 50ft into the hole. However, the entire hole is surveyed at 50ft depth intervals from the bottom of the hole towards the collar when it is situated in good ground conditions. Four Leica total stations are used for underground surveying at Stillwater Mine, with three of the total stations being TS06 one-second instruments and the fourth being a Leica 1200 fully robotic one-second instrument. At East Boulder Mine, two TS06 one-second total stations are used for underground surveying. Direction for development headings is design dependent. Linear drives greater than 500ft utilise McGarf sidewall lasers whereas those less than 500ft and radius designs use grade chains or removable sleeved McGarf lasers. An as-built stope survey is performed typically once a month and when a stope cut is mined out. All data collected each day is processed and stored in a database. Survey controls employed at both mines are primarily double, direct right angle survey points as well as a small amount of re-sectioning. Primary control points have tagged sequential numbers and there are more than 19 000 control points at Stillwater Mine and more than 5 000 control points at East Boulder
52 Mine. Temporary control points are hung from ground support and number over 200 000 control points. Control points are generally advanced at 100ft to 200ft spacing. Groundlines, back spans and sill angles are collected while advancing control. At the distance of approximately 2 000ft, a closed loop traverse is performed. The results of the traverse must close within established parameters (less than 1ft per 50 000ft) and errors are balanced and applied to the control database. The Qualified Persons are satisfied with the quantity and accuracy of the surface topography, collar and downhole survey data utilised for Mineral Resource evaluation. Given the insignificant drillhole deviation for the short definition drillholes at Stillwater and East Boulder Mines, there are no issues with the approach to complete downhole profiles for selected holes. Standard procedures are available for the execution of the survey work. Stillwater and East Boulder Mines each have a Chief Surveyor who is responsible for the oversight on all survey traverse work, calculation of the closed loop surveys in the Traverse PC Land Surveying software used and all survey sign-off. Density Determination Stillwater and East Boulder Mines have previously used a historical density (tonnage) factor of 11.6ft3/ton (equivalent to 0.086 ton/ft3) determined in 2000 from a limited dataset of J-M Reef intersections for all in situ tonnage estimation. In 2017, Sibanye-Stillwater introduced routine relative density (RD) determinations on representative J-M Reef intersections from Stillwater and East Boulder Mines prior to submission to the laboratory for analysis. The RD determinations are based on the Archimedes method and are performed by the Geologists. An expanded RD dataset accumulated since 2017 has been used for tonnage estimation. This indicates average density (tonnage) factors of 11.1ft3/ton (equivalent to 0.090 ton/ft3) to 11.3ft3/ton (equivalent to 0.088 ton/ft3) for the J-M Reef. Since FY2020, the density factor used for tonnage estimation at both the Stillwater and East Boulder Mines is 11.30ft3/ton (i.e., 0.09ton/ft3). The Qualified Persons support the approach to carry out routine determinations of RD on J- M Reef intersections prior to submission to the laboratory for analysis and the use of the accumulated RD data for tonnage estimation for improved accuracy of the tonnage and metal content estimates reported. Underground Mapping Routine underground geological and structural mapping is performed by Geologists as part of stope observation which also includes grade control face evaluation. Underground geological structural mapping inter alia captures the exact locations of the faults and dykes exposed in underground excavations, and the mapping information is transferred into AutoCad and/or Vulcan (and Deswik in future). The new information is integrated with existing information from previous surface and underground mapping. The updated structural maps support the drillhole data used for Mineral Resource estimation. This structural information is also utilised for short to long term rock engineering, hydrogeological, infrastructure and mine planning. 53 Hydrogeological Drilling and Testwork Stillwater Mine 9.9.1.1 Hydrogeological Characterisation A series of groundwater investigations at Stillwater Mine have been carried out since 2016 as part of the Blitz Dewatering Project. Itasca Denver, Inc. (Itasca) completed the groundwater studies on behalf of Sibanye-Stillwater. There has not been any groundwater investigation in the Stillwater West Section in recent years. The Stillwater West section has relied on actual experiences by the mine over the years in terms of groundwater inflows, impact of groundwater on geotechnical stability and mine dewatering requirements to prevent flooding. In general, there have not been any significant groundwater issues encountered in the Stillwater West Section, with major inflows of groundwater only experienced during the initial development into new areas. Subsurface development in the Stillwater East Section will take place beneath four surface drainage basins, which are – from west to east – Nye Creek, Burnt Creek, Prairie Creek, and Little Rocky Creek (Figure 14). Nye basin is a hanging, U-shaped valley formed during alpine glaciation in the Beartooth Mountains. The drifts and production areas of Stillwater East Section are being established in the crystalline rocks of the Stillwater Complex, which typically have low permeability. The portal for the Benbow decline is located in the Triassic Chugwater Formation, and the decline traverses southwest through older sedimentary units that include several Palaeozoic carbonate-rock units. The carbonate rocks have greater permeability and more groundwater storage capacity than the crystalline rocks of the Stillwater Complex. At 3 615 ft from the portal, the decline traverses the unconformity between the sedimentary rocks and the Stillwater Complex. Groundwater flow in the carbonate rocks is largely disconnected from the groundwater-flow network in the crystalline rocks of the Stillwater Complex. A number of north-south trending dykes and steeply dipping faults create secondary permeability and facilitate the flow of groundwater. Regional-scale, low-angle thrust faults striking roughly east-west (e.g., the Prairie Fault) are also present and tend to have substantial clay-rich (gouge) cores that impede the flow of water across the faults. However, these faults sometimes have damaged zones, which facilitate the flow of groundwater along the fault plane. 54 Figure 14: Sub-surface Water Basin in the Stillwater East Mine Area Climatic conditions drive groundwater recharge over the long term and directly influence the discharge/flow rates of meteoric-sourced springs and streams that issue from shallow groundwater systems in the short term. Direct infiltration of the seasonal snowmelt and runoff in the vicinity of the decline produce a minor amount of recharge to the groundwater system. 9.9.1.2 Hydrogeological Testwork and Data Collection For the groundwater investigations in the Stillwater East Section, Itasca recorded water pressures from underground drillholes, performed hydraulic (flow and shut-in) tests and collected groundwater samples for geochemical and isotopic analyses at eleven different locations, and developed analytical models to estimate inflow rates to the development drifts and future production areas. Itasca recorded water pressures and obtained water samples from ten hydrogeological boreholes at sites indicated in Figure 15 to determine flow rates and hydraulic conductivity (K) values. All of the instrumented drillholes were sampled for water chemistry and isotopic analyses, along with one of the non-instrumented probe holes. Water-pressure time-series data was automatically recorded by pressure transducers equipped with dataloggers at each of the instrumented drillholes. Hydraulic flow and shut- in tests were conducted during drilling using a special drill-collar manifold constructed by Itasca. The drill-collar manifold apparatus included a manual pressure gauge for water-pressure readings and a valve for regulating the flow through the manifold. Discharge from the manifold during a flow test was routed into a tank with graduated volume markings and was timed to make flow measurements. As 55 part of quality assurance and control, each instrumented location was retested post-drilling and after installing monitoring manifolds while allowing the water pressures to re-equilibrate following the perturbations caused by drilling. Figure 15: Hydrogeological Drillhole Locations along Adits in the Stillwater East Section 9.9.1.3 Hydrogeological Results and Interpretation The average hydraulic conductivity (K) values computed from the flow and shut-in/recovery tests vary between approximately 0.005ft and 4ft per day and are consistent with a range of values for fractured igneous and metamorphic rocks. The average K values are the best estimates of the rock mass near the drillholes. The geometric mean K value for all the full-hole-length flow and shut-in/recovery tests is 0.079ft per day. The Qualified Persons note that the full-hole-length tests provide a good representation of the “effective K” value of the overall rock mass as they account for both the occasional high-permeability fracture zones and the predominant less-fractured bulk rock mass of very low permeability. Since the bulk of the water flow in the rock mass is taking place along discontinuities (i.e., in the fractured zones created by faulting), the average K values computed from the flow and shut-in tests are primarily controlled by the density, aperture size and persistence of the discontinuities intersected by the drillholes. From the conceptual hydrogeological model of the Nye basin, steady-state analysis yielded the following estimates: • Average net surface-water exchange with 159gal per minute of groundwater discharge to Nye Creek; • Average recharge to the groundwater system of 663gal per minute; • Average discharge of groundwater to the historical mine development drifts at 450gal per minute; and
56 • Average groundwater outflow from Nye basin of 54gal per minute. Based on the conceptual hydrogeological model, average inflows from groundwater to the Stillwater East Section are estimated to be 883gal per minute for interception of recharge and 200gal per minute for depletion of water stored in the rock. This suggests that an average of approximately 1 100gal per minute would enter this section of Stillwater Mine. Refinements to the model based on the Perrochet analytical modelling predicted inflow rates as high as 1 500gal per minute by the end of the 25-year life of mine. Stillwater Mine determined that 1 600gal per minute would be the basis for the Stillwater East Section water treatment system. Updated modelling (March 2021) using the Stillwater East Ramp up plan is being completed at this time. The predicted total inflows to the development and production areas in all the basins combined indicated that the February 2021 Mine Plan would generate higher inflow rates during the first four years (FY2021 to FY2024) than mining under the December 2020 Mine Plan would generate during that same period. Thereafter, both mine plans are predicted to generate similar total inflow rates to the underground development and workings. The maximum increase in the total predicted inflow under the February 2021 Mine Plan, relative to the December 2020 Mine Plan, is approximately 360 gallons per minute and occurs near the end of FY2023. The total inflow rates are predicted to increase rapidly during the first three years and then to gradually level off starting in Year 4. Apart from the first four years, both mine plans are predicted to generate approximately the same inflow rates for the duration of the modelled time period (through FY2031), with overall maximum total inflow rates ranging between approximately 3 600gal and 3 800gal per minute after Year 4. The South Prairie Fault is a hydrogeologically important feature in the immediate vicinity of the J-M Reef and future production areas. This fault appears to limit southward-directed groundwater flow across the fault into the development drifts and future production areas in the Nye Creek Basin, which is beneficial to the mining operations. However, this situation may be different in the basins to the east of the Nye Creek Basin, due to a possible reversal of groundwater flow directions in the headwater portions of those eastern basins. East Boulder Mine 9.9.2.1 Hydrogeological Characterisation and Testwork A groundwater investigation was conducted in 1992 during the planning stage of East Boulder Mine primarily focusing on the path of the access adit. The Qualified Persons could not locate any information on quality assurance and control in reference to this investigation. Furthermore, no updated hydrogeology work has been completed since the inception of the mine. The 1992 groundwater investigation has been superseded by actual experiences by the mine over the years in respect of groundwater inflows, impact of groundwater on geotechnical stability and the requirements for mine dewatering to prevent flooding. 57 The Qualified Persons note that the risk to encounter major inflows of groundwater is likely during the initial development into new areas. During the development of the adit, the only significant water was encountered where diamond drill water probes produced a maximum of 80gal to 100gal per minute of inflow. However, most of these holes bled off to flows less than 80gal per minute over time, with any holes that did not bleed off controlled through grouting. Figure 16 shows the average water inflow into the mining operations at East Boulder Mine. Water inflows increased from 61gal per minute in 2010 to a peak of 246gal per minute in 2013 but have ranged from 211gal per minute to 249gal per minute thereafter until 2020 after which inflows receded to an average of 184gal per minute. The post-2010 levels of water inflow ranging from 61gal per minute to 249gal per minute should be expected at East Boulder Mine. Figure 16: Average Water Inflow at East Boulder Mine 9.9.2.2 Hydrogeological Results and Interpretation The Qualified Persons note that much of the area being mined at East Boulder Mine is adjacent to active mining fronts, which have historically had no issues with groundwater. The lowest level of the mine currently acts as a drawdown point for surrounding groundwater levels. Most of the mining areas continue to be above this drawdown point and the inflows are likely to be similar or lower than those experienced by historical mining operations. The average mine-wide water inflow is only likely to increase slightly with the increase in development and production activity associated with the Fill the Mill Project. All mining activity will remain within the crystalline rocks of the Stillwater Complex, which have very low permeability. Water will likely be encountered when it relates to the intersection of faults and joints. However, there is risk of encountering alluvial systems associated with surface channels as mining gets 61 109 153 246 224 211 229 217 223 248 249 184 0 25 50 75 100 125 150 175 200 225 250 275 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 W a te r In fl o w ( G a l/ M in u te ) Year 58 to within 500ft from surface. Standard practice during underground development at East Boulder Mine includes the diamond core drilling of water probe holes prior to any development work to mitigate the risk of encountering water. Prior to mining any area, diamond core drilling on 50ft centres is also completed resulting in a good understanding of water potential before mining activity begins. Geotechnical Data, Testing and Analysis Geotechnical Characterisation The J-M Reef and its immediate hangingwall and footwall consist of varying assemblages of norite, anorthosite, leucotroctolite and peridotite. Mafic dykes traverse the J-M Reef, Footwall and Hangingwall Zones. The dyke material is generally blocky, slick and akin to the nature of the jointed host rock. Stillwater and East Boulder Mines constitute the two main geotechnical ground control districts. The J-M Reef is mined at the following depth ranges: • Stillwater West Section: Shallow to intermediate, onset of stress fracturing deeper than 3 300ft below surface. At depths less than 3 300ft below surface, joint and structural lineament influence stability and tensile zone; • Stillwater East Section: Shallow to intermediate depth of mining environment, joint and structural lineament influence stability, tensile zone and, in deeper areas, stress fracturing combines with micro fractures to stimulate mobilisation effects; and • East Boulder Mine: Predominantly shallow environment. The effects of mine seismicity have not had a significant influence to the mining operations at Stillwater and East Boulder Mines. This is because, at current mining depths at the Stillwater and East Boulder Mines, the propensity for mining induced seismicity (strong ground motion) is low. The probability of natural earthquake induced strong ground motion is also low. East Boulder Mine has a micro-seismic system installed and monitors blasts and seismic events daily. Geotechnical Testwork and Data Collection Rock engineering and support designs utilised at Stillwater and East Boulder Mines have been developed using a combination of geotechnical drillcore logging and underground mapping data. Geotechnical drillcore logging is the primary method of gathering rock strength and quality parameters. Geotechnical logging is completed by Geologists on drillcores recovered from surface exploration and underground probe and definition diamond core drilling. The definition drillholes at Stillwater Mine that are considered for geotechnical logging include the first down hole and up hole at a drill station, sill holes and holes identified as low and high-grade mineralisation at the time of logging. Furthermore, drill core for straight-ahead and south-directed probe holes are geotechnically logged. At East Boulder Mine, geotechnical information is collected on all drillholes. In general, the geotechnical data is collected at a drillhole spacing of 50ft. In general, the entire J-M Reef is geotechnically logged, with the logging extended 1ft to 15ft into the immediate Footwall and Hangingwall Zones. Geotechnical logging involves the determination of core recovery, Rock Quality Designation (RQD), fracture frequency, number of joint sets, joint roughness, joint alteration, nature of fracture fill and Point Load Index. As the drillcores are not oriented, the joint 59 orientations and number of joint sets recorded are estimated through visual inspection of drillcores backed up by underground mapping information. Point load tests are performed on intact rock cores. Due to the destructive nature of this technique on the sample, it is impractical to perform a duplicate test. The most practical quality assurance and control entails comparing the new result to the existing data for a similar type and neighbouring drillholes. A new result that varies significantly (>10%) in the absence of shearing and a concomitant low RQD (<70%) is adjudged to be a spurious result which should be excluded from the database. The geotechnical data is stored in the Ore QMS database and utilised for rock engineering. Other geotechnical parameters determined are the uniaxial compressive strengths (UCS) and the International Society for Rock Mechanics (ISRM) grading for intact strength of the J-M Reef and the immediate hangingwall and footwall zones. UCS is calculated from the Point Load Index through regression. Barton’s Q-system is exclusively used to classify the rock mass characteristics at Stillwater and East Boulder Mines. A combination of drillcore and underground ground evaluation data on the geotechnical parameters above is used for the computation of Q-values used to classify rock mass conditions. Measurements of in situ stress were conducted at the mines in 1997, 2002 and 2016 using hollow inclusion stress cells. The initial (1997 and 2002) stress measurements were conducted under mountain and valley terrains within Stillwater Mine (Figure 17), whereas the most recent (2016) measurement at East Boulder Mine was performed at test sites where there has been minimal stoping (Figure 18). The Qualified Persons could not locate any information in relation the pre-2016 in situ stress. However, duplicate tests were performed as quality control and assurance for 2016 measurements. In most cases, the results were repeatable. The isolated incidences of significant variations between duplicate measurements were investigated and rectified during data collection. Figure 17: Test Sites for In Situ stress Measurements at Stillwater Mine
60 Figure 18: Test Sites for In Situ Stress Measurements at East Boulder Mine Geotechnical Results and Interpretation A recent geotechnical dataset indicates overall core recoveries for the J-M Reef, Footwall and Hangingwall Zones of above 96% (Table 9). Core recovery is the initial indicator used to predict potential ground control issues. The database also shows RQDs above 75% for most (over 69%) of the logged drillcore intersections, which indicates fair to good rock mass conditions. Over 78% of the sampled intervals have rock strengths above the 3 500Psi threshold considered weak rock. Sections with lower strengths than this threshold are commonly associated with olivine cumulates or geological structures. When these rock types and structures are identified in the drillcores, the mining and support designs are adjusted accordingly. The UCS of the rock units contained within the J-M Reef, Footwall and Hangingwall Zones range from 60Mpa to 85Mpa (overall mean of 70.45Mpa). The ISRM Grade R4 classification for the intact strength of all the stratigraphic units indicates a strong rock (i.e., UCS of 50MPa to 100Mpa). Table 9: Summary of Geotechnical Parameters Stratigraphic Unit Average Core Recovery (%) Average UCS (MPa) Average RQD Average Rock Strength (Psi) Average Q-Value Hangingwall 96.30 65.41 77.83 12 184.59 8.16 J-M Reef 97.00 61.93 80.74 9 486.48 8.24 Footwall 96.20 84.01 76.40 8 982.68 6.19 Mean 96.50 70.45 78.43 1 0812.86 7.83 The three most prominent joint orientations observed in underground excavations are associated with the following geological structures: • North-northeast (020°) striking, steeply dipping faults; • Northeast striking mafic dykes with dips of 35° to 70° towards southeast; and • Westerly striking, layer parallel joints with dips of 45° to 90° towards north. 61 The crosscutting nature of the joints periodically creates wedges in the backs and ribs of the mine openings. The Q-Values obtained for Stillwater and East Boulder Mines typically range from 1 to 13 (average for the Footwall, J-M Reef and Hangingwall Zones is 7.83; Table 9) and the rock mass can be classified as poor to good. Approximately 50% of the rock mass is classified as fair, 25% is classified as good and 25% is classified as poor. Conditions are generally dry with rare occurrences of low-pressure low-volume water inflows. The stress reduction factors (SRFs) used to calculate the Q-ratings have a mean value of 1.88 while joint water conditions range from dry (SRF = 1.0) to medium inflow (SRF = 0.66). Measurements of in situ stress indicate that the horizontal to vertical stress ratios at Stillwater and East Boulder Mines are typical for shallow to intermediate operations: • 1.5 to 1.9 for valley areas at Stillwater Mine; • 0.8 to 1.9 for mountain areas at Stillwater Mine; and • 2.4 for East Boulder Mine. Other associated data on stress orientations and magnitudes help form a portion of the input parameters for numerical assessments of development and stope stability, local and regional sequencing and support design. 62 SAMPLE PREPARATION, ANALYSES AND SECURITY Sampling Governance and Quality Assurance The Qualified Persons are satisfied with the standard procedures for geological data gathering used at Stillwater and East Boulder Mines which prescribe methods that are aligned to industry norms. The governance system at Stillwater and East Boulder Mines relies on directive control measures and, as such, makes use of internal manuals (standard procedures) to govern and standardise data collection, validation and storage. Furthermore, the standard procedures are mandatory instructions that prescribe acceptable methods and steps for executing various tasks relating to the ongoing collection, validation, processing, approval and storage of geological data, which is utilised for geological modelling and Mineral Resource estimation. In addition to internal standard procedures, Sibanye-Stillwater implements an internal analytical quality control protocol for the routine assessment of laboratory performance and quality of analytical data from the laboratory. As required by the protocol, batches of samples sent to the laboratory include routine “blank” samples (hangingwall and footwall anorthosite samples) and pulp samples from previous sample batches (repeat samples) analysed at the laboratory. Results of the analytical quality control are discussed in Section 10.4. The governance system also emphasises training to achieve the level of competence required to perform specific functions in the data gathering, validation and storage. Extensive on-the-job training of new Geologists, who will eventually be responsible for logging and sampling, is performed. Lithological and geotechnical data is acquired through the logging of drillcores recovered from surface and underground drilling. The logging is undertaken by trained Geologists, who are familiar with the J- M Reef, footwall and hangingwall stratigraphy and rock types. Existing drillhole information from previous core logging guide ongoing core logging and any deviations from the expected rock types and stratigraphic sequence observed during logging are investigated further by the Geologists supervising the logging. Routine validations are undertaken by the experienced Geologists at various stage gate points in the data collection process flow, with the ultimate validations performed by the Qualified Persons. The Qualified Persons note that the internal peer review of the data facilitates the early detection of material errors in the data capture before the collection is finalised. Another aspect of the governance system is the documentation of the geological data gathering process flow (i.e. data collection, processing and validation). The Qualified Persons acknowledge that this documentation facilitates the auditability of the process flow activities and outcomes as well as the measures undertaken to rectify anomalous or spurious data. Surface core storage facilities at Stillwater and East Boulder Mines are secure and accessed by authorised geological personnel. In addition, the facilities are part of the surface infrastructure at the mine sites which are fenced off to prevent unauthorised entry by the public and animals, with access restricted to the Sibanye-Stillwater US PGM Operations employees. 63 Reef Sampling The sampling procedure at Stillwater and East Boulder Mines requires the sampling of all mineralised intersections of the J-M Reef containing visible sulphide minerals. For this sampling, it is critical to break the sample intervals taking into account variations in sulphide mineralisation abundance and lithology. Furthermore, a break in sampling should always occur at the hangingwall contact. This approach facilitates efficient assessment of the analytical results of the sampled sections. The laboratory requires a minimum sample size equivalent to 0.5ft in length for BQ-size drill core. As a result, reef samples are taken in 0.5ft to 3ft segments and the sampling is extended by 1ft to 3ft into the footwall and hangingwall of the mineralised intersections. Sampling may be extended further into the footwall zones that are mineralised. Sample lengths can also be varied when sampling large internal waste zones where the sample interval can be extended to 4ft or only a fraction of the drilled core was recovered during drilling due to poor ground conditions in which case the full 5ft between running blocks is taken. An internal waste zone of less than 10 inches between mineralised zones should be sampled together with the mineralised zones but is assigned a zero grade. In order to ensure sample representivity in light of the very coarse-grained nature of the J-M Reef, the entire drillcore sample is submitted to the analytical laboratory and no core splitting is performed. Accordingly, there is no risk of contamination, selective losses or high grading associated with the sampling of the recovered drillcores at Stillwater and East Boulder Mines. The samples are assigned unique sample identification numbers and tags before they are transported to the laboratory by Geologists. In addition, the samples for each drillhole and the associated quality control samples (repeat and blank samples) are submitted to the laboratory on the same day that the sampling takes place, failing which they should be submitted during the morning of the following day. The Geologists prepare sample submission sheets that accompany the samples. Both the samples and sample submission sheets are placed in customised bins from which they are received by the laboratory personnel. Records of the sample data are captured in the Ore QMS database. Sample Preparation and Analysis Laboratory Samples from Stillwater and East Boulder Mines are analysed at the analytical laboratory located at the Columbus Metallurgical Complex which is owned and operated by Sibanye-Stillwater. The Qualified Persons can confirm that the analytical laboratory is a secure facility as it is situated in the Columbus Metallurgical Facility which is fenced off to prevent unauthorised entry by the public and where access is restricted to only authorised personnel of the Sibanye-Stillwater US PGM Operations. The laboratory has facilities for sample preparation and chemical analysis (via fire assay and instrumental techniques). It is equipped with the Laboratory Information System (LIMS) software, which facilitates effective and efficient management of samples and associated data. The analytical laboratory was automated with wavelength dispersive and energy dispersive X-Ray Fluorescence (XRF)
64 instrumentation as well as robotic sample preparation facilities in 2011. It handles geological drillcore and grade control samples as well as samples from the concentrators, smelter and base metal refinery. The laboratory is not certified by any standards association. The Qualified Persons do not consider the absence of certification as a material issue on the basis that the laboratory is subjected to periodic external checks on internal samples by a group of six international accredited laboratories. Furthermore, the Qualified Persons periodically inspect the laboratory facilities, interact with laboratory personnel and assess analytical data from the laboratory as they carry out their normal duties. These activities are aimed at detecting and eliminating any material issues in the sample preparation, analytical equipment and methods utilised by the laboratory for geological samples. Sample Preparation and Analysis The laboratory employs industry aligned approaches to sample receiving, preparation and analysis and the reporting of analytical results. Drillcore samples originating from Stillwater and East Boulder Mines are transported to the Columbus Warehouse in totes via third-party carrier. Laboratory personnel retrieve the totes from the Columbus Warehouse in the cargo holds of site vehicles. Sample batches received at the laboratory are reconciled against submission sheets and any discrepancies identified are reported to the Geologists for rectification prior to sample preparation. Sample preparation includes sample drying, crushing and milling. The drillcore samples of approximately 4.4lb to 11lb mass are dried at a temperature of 221°F for approximately two hours, organised into sets containing up to 22 samples and assigned tags with bar codes. The barcoded sample labels are scanned and logged into the LIMS after which the samples are run through a primary and secondary jaw crusher producing material grading 100% passing 0.25 inches. The processes utilised for sample size reduction after crushing are performed by robotic equipment thereby minimising the potential for bias or sampling error. The crushed material is split down to approximately 0.40lb to 0.44lb using a Jones riffle splitter and introduced into the robotic sample preparation system (HPM1500). This system sequentially pulverises each sample to achieve 95% passing 140-mesh size (i.e., 106µm particle size) in an automated grinding mill. Grind tests are performed quarterly to ensure the correct grind size is always achieved. Analyses are performed through the dual analytical route of XRF analysis and lead fire assay (PbFA) collection followed by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) for metal content determination. Silver (Ag) is introduced into the flux as a co-collector in the PbFA process to help collect the precious metals in the geological samples. Results produced by both XRF and PbFA + ICP-OES analytical techniques are total analyses that reflect potentially extractable in situ values of the target metals (Pd and Pt) reported in the Mineral Resource statements for Stillwater and East Boulder Mines. A portion of the pulverised material is weighed, mixed with binder and loaded into an automated pellet press. Balances used for charging fire assay samples are tested for accuracy, with each shift required to use certified check weights. Furthermore, a third party performs preventative maintenance and calibration annually on the scales. An XRF analysis is performed on the pressed pellet. The remaining 65 sample material is taken to the fire assay balance room. The fire assay (FA) process comprises the following steps: • Fusing the primary and standards samples with a Pb-based flux at 2 084°F; • Separating the Pb to form a Pb button; • Cupellation to form a precious metal bead (PbFA-collection); • Bead digestion in aqua regia; and • Metal content determination via ICP-OES analysis of the digestion solution. All analytical results are reported directly into the LIMS via the instrumentation and forwarded to the Geologists electronically, which eliminates the risk of data capture error. The instrument lower detection limits (LDL) for the analytical processes employed are 5ppb for Pd and 10ppb for Pt. The XRF analysis also produces results for multiple elements and oxides, but the LIMS is configured to report only the elements of significance (Pd and Pt) required for PGM evaluation. For the PbFA collection and ICP-OES analysis, only Pt, Pd and Au values are determined although only the Pd and Pt values are reported. The Pd data reported from the XRF analysis is compared with the Pd data based on the PbFA collection technique before the analytical reports are finalised. Any discrepancies are investigated and rectified before the report is finalised. The laboratory has in place quality assurance and control procedures for the analysis and handling of the samples. The laboratory operates separate lines for the receiving, preparation and analysis of low- grade (e.g., geological) samples and high-grade (e.g. concentrate) samples, with an overall high level of cleanliness maintained to minimise contamination. Furthermore, the laboratory standards and blanks are also included in each sample batch and any anomaly identified in the quality control samples is addressed as required. As there are no commercially available independent standards of the J-M Reef mineralisation, the laboratory manufactures its own internal standards, which it sends out to external laboratories periodically for check analysis. The laboratory uses these internal standards to monitor analytical accuracy and the analytical data for the standards is made available to the Geologists at their request. The Qualified Persons are satisfied with the sample preparation, analytical methods, accuracy and precision and the level of cleanliness at the analytical laboratory. The analytical methods employed are suited to the mineralisation style and grades of the J-M Reef and are widely used in the PGM sector. Accordingly, the analytical data from the laboratory is a suitable input for grade estimation. Analytical Quality Control Nature and Extent of Quality Control Procedures Sibanye-Stillwater implements an analytical quality control protocol requiring ongoing monitoring of the laboratory performance by the Geologists at Stillwater and East Boulder Mines. This protocol has been in use since 2006. All sample batches from the mines submitted to the laboratory include matrix matched blank samples (drawn from hangingwall and footwall anorthosite) and repeat (pulp) samples introduced by Geologists to assess laboratory performance on contamination and analytical precision, respectively. The pulp samples are carefully selected to monitor precision across the 2E grade spectrum 66 as follows: 0.00-0.19opt (waste), 0.20-0.49opt (low-grade), 0.50-0.99opt (high-grade) and 1.00opt and above (very high grade). In general, the insertion rates for quality control samples included in sample batches at each of East Boulder Mine and the East and West Sections of Stillwater Mine ensure that at least ten blank samples and ten repeat samples from each of these areas are analysed at the laboratory every month. Currently, there are no certified reference materials (standards) of the J-M Reef prepared by independent suppliers and the geological personnel at Stillwater and East Boulder Mines rely on the analytical results of in-house developed standards (MF-series standards) introduced into geological sample streams by the laboratory personnel to monitor the accuracy of the laboratory analytical procedures. Analysis of the repeat and blank sample analytical data is an ongoing process and any issues identified are investigated and rectified by the geological and laboratory personnel. Quality Control Results Analytical results for the blank and repeat samples and internal standards are analysed graphically on control charts to facilitate the identification of anomalous data points. This assessment also includes the following: • Review of sample results from the laboratory for abnormal Pt:Pd ratios or abnormally high grades before any analytical results are accepted into the Ore QMS database; • Comparison between visual sulphide mineral estimates made during the core logging and grades after the analytical results are accepted into the Ore QMS database. Occurrences of sulphide minerals with no associated/expected Pt and Pd values or high Pt and Pd values where there are no significant visible sulphide minerals are noted and investigated; and • Identification of anomalous repeat and blank sample data and standards data on control charts over time to identify any trends in the data. If any of these steps show indications of possible problems, the Geologists request for re-analysis of the affected samples or sample batches. Repeat sample data for Stillwater and East Boulder Mines collected since 2006 was reviewed on an ongoing basis during collection but for the purposes of this Technical Report Summary was reviewed further by the Qualified Persons using control charts, in terms absolute mean error deviation and scatter plots as indicated in Figure 19 and Figure 20 for Stillwater and East Boulder Mines, respectively. An absolute mean error deviation value less than 10% or a squared correlation coefficient (R2) value shows high analytical precision. In general, 86% and 96% of the repeat data for Stillwater and East Boulder Mines, respectively, indicates high precision (mean percent difference <10%; R2>0.8) of the analytical procedure. However, samples with low grades close to the instrument analytical detection limits (i.e., from the waste zones) are often associated with low precision and these constitute 4% and 14% of the repeat sample datasets for East Boulder and Stillwater Mines, respectively. Furthermore, there were isolated incidences of anomalous data, which necessitated re-analysis of the affected samples or rejection of the results if the anomalous data could not be resolved. In most of these cases, the second and third analyses were comparable, which suggests that the problem was related to sample selection and labelling (i.e. sample swapping and mislabelling) by the geological personnel rather than poor precision by the laboratory. 67 Figure 19: Repeat Data Analysis for Stillwater Mine Figure 20: Repeat Sample Data Analysis for East Boulder Mine The blank material utilised at Stillwater and East Boulder Mines has no certified value. As a result, the blank sample data is analysed visually on plots to identify anomalous values that may suggest overwhelming contamination or sample swapping. The blank sample data for Stillwater and East Boulder Mines collected since 2006 was also reviewed further by the Qualified Persons for the purposes of this Technical Report Summary (Figure 21). In general, the blank sample values for both mines are similar, with most of the blank samples having values that are lower than the grade threshold of 0.2opt utilised for reef and waste material discrimination, which discounts the presence of overwhelming cross sample contamination. Isolated incidences of elevated PGM values returned on some blank samples may be attributed to localised elevated abundances of PGMs in the hangingwall and footwall anorthosites used as blank material and may not necessarily reflect contamination at the laboratory during sample preparation. While there is no evidence of overwhelming sample contamination, the Qualified Persons recommend the inclusion of certified blank material with insignificant levels of Pd and Pt to definitively assess the extent of any contamination at the laboratory.
68 Figure 21: Blank Sample Data Analysis for Stillwater and East Boulder Mines The Qualified Persons procured the internal standards analytical data from the laboratory to assess the level of accuracy to which the geology samples have been analysed. The laboratory provided data for standards material MF-14 to MF-21 as well as the applicable expected (mean) values, Lower Control Limits (LCLs) and Upper Control Limits (UCLs) presented in Table 10. The data was analysed using control charts in Figure 22 to Figure 26, all of which show acceptable accuracy and precision levels for the standards analytical data. Accordingly, the analytical data for the sample batches analysed together with these internal standards is deemed acceptable for inclusion in the database for Mineral Resource estimation. Table 10: Details of the In-house Standards Name of Standard Description Pd (ppm) Pt (ppm) MF-14 Expected 16.87 4.82 LCL 15.99 4.37 UCL 17.96 5.20 MF-15 Expected 7.65 1.61 LCL 7.32 1.48 UCL 7.97 1.74 MF-16 Expected 7.52 1.58 LCL 7.25 1.46 UCL 7.80 1.71 MF-18 Expected 4.23 0.93 LCL 4.06 0.85 UCL 4.58 1.07 MF-20 Expected 14.97 3.72 LCL 13.85 2.81 UCL 16.07 4.63 MF-21 Expected 9.41 1.95 LCL 8.87 1.73 UCL 9.95 2.16 69 Figure 22: Laboratory Standard MF-14 Data Analysis Figure 23: Laboratory Standard MF-15 Data Analysis Figure 24: Laboratory Standard MF-16 Data Analysis 70 Figure 25: Laboratory Standard MF-18 Data Analysis Figure 26: Laboratory Standard MF-20 Data Analysis Figure 27: Laboratory Standard MF-21 Data Analysis Based on the foregoing, the Qualified Persons conclude that the laboratory’s analytical data shows overall acceptable precision and accuracy, and no evidence of overwhelming contamination that would affect the integrity of the data. As a result, the analytical data from the inhouse laboratory is of acceptable integrity and can be relied upon for Mineral Resource estimation. 71 DATA VERIFICATION Data Storage and Database Management All the drillhole data (i.e., collar and downhole survey, lithological, geotechnical, structural, analytical, and mineralisation data) for Stillwater and East Boulder Mines is stored in the Ore QMS database, which is an in-house built database designed to standardise information gathering during drilling. The data is imported electronically from the Core Logger system into the database. Library tables, key fields and codes are the validation tools available in the Ore QMS database utilised for ensuring correct entries. The Ore QMS database is stored on the central IT server where it is backed up and has rigorous controls (e.g., password protection and access restrictions) to ensure security and integrity of the data. The drillhole data stored in the Ore QMS database is exported to Maptek VulcanTM (Vulcan) modelling software, which provides additional backup. The Qualified Persons are satisfied with data storage and validation as well as the database management practices, which are all aligned to industry practice. There are sufficient provisions to ensure the security and integrity of the data stored in the Ore QMS database. Database Verification Internally generated surface exploration and underground definition drillhole data is the primary data utilised for geological modelling and Mineral Resource estimation at Stillwater and East Boulder Mines. The Qualified Persons did not perform independent verifications of the data collected but relied on the rigorous validations performed during data collection and processing to which they participate. Surface topography survey data used was sourced from the USGS and this was validated by comparing it with existing survey data. The high-resolution topographic survey data was found to have better accuracy than existing survey data used for previous Mineral Resource estimations. The validation of drillhole data is a continuous process completed at various stages during data collection, before and after import into the Ore QMS database and during geological modelling and Mineral Resource estimation. As the Qualified Persons are fulltime employees of Sibanye-Stillwater, they either performed or supervised the validation of the drillhole data collected at the mines after which they approved and signed-off the validated data for Mineral Resource estimation. The Mineral Resource estimates for both mines are based on the validated drillhole data collected by Sibanye-Stillwater and its predecessors, which is stored in the Ore QMS database. The current drillhole databases for Stillwater and East Boulder Mines contain data relating 47 312 and 11 489 drillholes, respectively. The databases contain 101 773 assays for Stillwater Mine and 80 179 assays for East Boulder Mine. After data validation, data pertaining to 41 655 and 9 948 drillholes was used for the 2021 Mineral Resource estimation at Stillwater and East Boulder Mines, respectively. The primary elements of the drillhole data are the following: • Survey data: drillhole collar co-ordinates, azimuth, dip and down hole surveys; • Lithological data: descriptions of rock type, mineralisation, alteration and geological structures; and
72 • Analytical data: chemical analyses for Pd and Pt for each sample of the J-M Reef analysed at the laboratory. In general, the lithological data is acquired through the routine geological logging of drillcores recovered from surface and underground diamond core drilling. The Geologists who log the drillcores are well trained and familiar with the J-M Reef, footwall and hangingwall stratigraphy and rock types. In addition, they are supervised by appropriately experienced Geologists who review their log sheets. The core logging is performed according to a standard procedure which standardises data gathering, and the type of detail required for each drillhole log, with any deviations or anomalous entries flagged by the inbuilt validations tools available in the Ore QMS database system. During core logging, the Geologists also consider existing drillhole information and any deviation from the expected rock types and stratigraphic sequence are investigated further by the Senior Geologists supervising the logging. Analytical data is received electronically from the laboratory and imported electronically into the database, where it is integrated with the relevant lithological and survey data. Prior to finalisation of the import, the analytical data is assessed, accepted for use and stored in the database according to the analytical quality control protocols discussed in Section 10.4. All drillhole survey data is reviewed and signed-off by the Chief Surveyors. Geologists also validate the survey data by comparing it against planned coordinates and through visual checks in the Vulcan software environment. The imports into the Ore QMS database and validations are performed by experienced geological personnel. In the Ore QMS database, the data is validated for missing and incorrect entries through spot checks completed on strip logs (logs of the integrated data) and using the inbuilt validation tools. The drillhole database is also periodically checked using a Vulcan program script that automatically checks for missing, overlapping or inverted analytical intervals during data import. Additional validations include comparisons of survey database entries against surveyed 3D models of the footwall lateral drifts to validate that drillhole collar coordinates, azimuth and inclination. Downhole metal profiles for each drillhole are compared against expected profiles for each geological domain and any discrepancies are investigated further and addressed. The Qualified Persons acknowledge the rigorous validation of the extensive drillhole database utilised for Mineral Resource estimation at Stillwater and East Boulder Mines. The data was validated continuously at critical points during collection, in the Ore QMS database and during geological modelling and Mineral Resource estimation. The Qualified Persons either participated in or supervised some of the validations which were performed by suitably trained personnel. The Qualified Persons also approved the use of the validated drillhole data which was signed-off for Mineral Resource estimation. The Qualified Persons confirm that the data validations are consistent with industry practice while the quantity and type of data collected are appropriate for the nature and style of the PGM mineralisation in the J-M Reef. 73 MINERAL PROCESSING AND METALLURGICAL TESTING Metallurgical Testwork and Amenability There has not been any recent relevant metallurgical testwork completed for the Stillwater and East Boulder concentrator plants, smelter and base metal refinery at the Columbus Metallurgical Complex. The Qualified Persons are of the view that the testwork has not been warranted as the Stillwater and East Boulder concentrator plants and the Columbus Metallurgical Complex facilities have all been operational for several decades and have been upgraded and modified over the years to take account of new technology and increased capacity. Process flow diagrams for the various installed plants are presented in Section 16 and these are based on industry aligned PGM process flows and technology. Detailed flow sheets, mass balances and metallurgical accounting schedules are available for all the operations. The metallurgical and mineralogical characteristics of the ore from the J-M Reef are well-understood and metallurgical recoveries of the ore processing and mineral beneficiation operations are based on detailed historical production data accumulated over many years. As the Stillwater and East Boulder Concentrators and the Columbus Metallurgical Complex facilities have all been operating sustainably, metallurgical amenability predictions for Stillwater and East Boulder Mine ores and associated forecast budget tonnage throughput rates and metallurgical recoveries are based on historical experience and supported by operational data reviewed (Section 16.1). Ore from the Stillwater East (Blitz) Section has been processed at the Stillwater Concentrator since 2017. Experience from the processing of this ore indicates that the J-M Reef in this section is metallurgically similar to that in the Stillwater West Section and that the ore has not behaved any differently during processing at the Stillwater Concentrator. Deleterious Elements The Qualified Persons are not aware of any reports of deleterious elements in the concentrate produced from the processing of J-M Reef ore at the Stillwater and East Boulder Concentrators. The ores produced from the mines have been successfully processed for several decades and the Qualified Persons consider it reasonable to expect that there will not be any deleterious elements in the unmined parts of the J-M Reef. Neither bulk nor pilot scale testing has been necessary as the processing facilities have all been operational for several decades. 74 MINERAL RESOURCE ESTIMATES Background An extensive drillhole database relating to 41 655 and 9 948 drillholes at Stillwater and East Boulder Mines, respectively, was utilised for 3D geological modelling of the J-M Reef and the Mineral Resource estimation. The 3D geological modelling of the J-M Reef and Mineral Resource estimation, which were performed internally by Sibanye-Stillwater personnel, are based on a common estimation process flow and methodology that suit the architecture, mineralisation style and variability of the J-M Reef at the mines. The process flow is well-established and provides for mandatory checks and validations by the Qualified Persons at critical points in the Mineral Resource evaluation process. The Qualified Persons participated in the 3D geological modelling of the J-M Reef and the Mineral Resource estimation for Stillwater and East Boulder Mines and approved the key inputs and outputs at each stage gate as well as the final 3D geological models and estimates reported. The point of reference for the Mineral Resource estimates for Stillwater and East Boulder Mines is an in situ tonnage and grade estimate of the J-M Reef material for which there are reasonable prospects for eventual economic extraction. Furthermore, estimates are completed for the combined Pd and Pt grades (2E) and reef thickness, but co-products or by-products which occur at low abundances were not estimated. There have been no deleterious elements identified in the J-M Reef since the start of the mining and ore processing operations at Stillwater and East Boulder Mines. Accordingly, no deleterious elements were estimated. A consistent estimation and evaluation approach was employed for Mineral Resources eventually classified as either Measured, Indicated or Inferred at both Stillwater and East Boulder Mines. The approach is aligned to the conventional estimation and evaluation methods employed for other tabular PGM reefs which are characterised by long-range thickness and grade continuity. The Mineral Resources in this Technical Report Summary are reported at a minimum mining width and cut-off grade and exclude the J-M Reef mineralisation within the 50ft crown pillar from surface and in structurally disturbed areas. Geological Modelling and Interpretation Zone Picking and Evaluation Cut Determination The Main Zone constitutes the well-mineralised economic part of the J-M Reef that is included in the Mineral Resource evaluation cuts termed the reef channel. However, there are localised occurrences of well-mineralised footwall material included in the evaluation cuts. The Main Zone intersections employed for 3D geological modelling are identified and selected by Geologists through a manual process called zone picking. The Geologists use the hangingwall as a reference on the basis that between 80% and 90% of the Main Zone intersections occur near the hangingwall. For each drillhole, validated analytical data is integrated with relevant lithological and sample data to generate an integrated log sheet (strip log) employed for zone picking. 75 Zone picking entails scanning the integrated log sheet of a drillhole to identify the hangingwall of the J- M Reef package. From the hangingwall contact, the underlying mineralised zone (Main Zone and mineralised portions of the immediate footwall units) is identified and delineated using a composite 2E grade threshold of 0.20opt. For each drillhole J-M Reef intersection, the selected portions are assigned a unique identifier geology code indicating that these can be included in the evaluation cut dataset. Zone picking also includes the consideration of neighbouring drillholes in a particular drill section and adjacent drill sections to ensure smooth extension of the zone picks between drillholes and drill sections. For poorly mineralised reef intersections with 2E grades below 0.20opt, a single sub-ore grade value is flagged at the hangingwall contact. If no analytical data was collected because of the total lack of any sulphide minerals in the drillcore, a 0.5ft or 1ft blank interval is input and flagged at the hangingwall contact of the J-M Reef. Such intersections are assigned a 2E grade equivalent to the LDL during modelling. Zone picking on these intersections requires diligence and experience by the Geologists as there are between 10% and 20% of intersections located in the footwall (localised footwall mineralisation), duplicated or disturbed by geological structures (e.g., mafic intrusions and faults) that need to be identified. These mineralised footwall zones and repeated Main Zones are flagged with unique zone identification numbers, which permit separate assessment and modelling of these zones. The Qualified Persons are satisfied with the zone picking method used to discriminate between mineralised and waste zones as this is appropriate for the nature and style of the J-M Reef and ensures consistency in the delineation of reef composites used for geological modelling and estimation. The Qualified Persons noted that the 0.20opt 2E grade threshold employed for the zone picking (reef channel delineation) is conservative as this is higher than the cut-off grades used for Mineral Resource reporting. Mineral Resources are reported at the minimum mining width (thickness) which can be wider than the reef channel, which justifies the use of a higher grade threshold for zone picking. Data Processing and Analysis 13.2.2.1 Compositing Industry practice was followed for evaluation cut (reef channel) data processing and analysis. Subsequent to zone picking and coding, the evaluation cut data for each drillhole comprising collar and downhole survey, stratigraphic, lithological and analytical data for each drillhole was imported into Vulcan and integrated and positioned into the correct three-dimensional (3D) space through an automated process called de-surveying. The integration of the data allowed for the following validations: • Examination of the sample analytical, collar survey, downhole survey and lithological data to ensure that all drillholes had complete data on the key estimation variables; • Examination of the data to check for spatial errors; • Examination of the analytical data to identify out of range and anomalous data; and • Checking of sample intervals to identify overlaps and unexplained gaps between samples. The integrated data was composited in Vulcan by geology code and using the drillhole collar survey, azimuth, inclination and analytical data for each zone pick (evaluation cut). This process resulted in new X, Y, and Z collar co-ordinates, single composite values for Pt, Pd and 2E and thickness for each drillhole
76 Main Zone intersection. The drillhole composite grades were derived through length weighted averaging of the sample grades in the evaluation cuts. The composite data was utilised for geological block modelling as well as grade and thickness estimation. 13.2.2.2 Statistical Analysis and Grade Capping Statistical analysis was performed in Datamine Supervisor software (Supervisor). Prior to statistical analysis, the evaluation cut datasets for Stillwater and East Boulder Mines were reviewed to identify zero values assigned during zone picking. J-M Reef intersections which were assigned zero values amounted to approximately 15% of the Stillwater Mine dataset whereas these constituted 1% of the East Boulder Mine dataset. The zero values were replaced by the LDL value for 2E (5ppb for Pd, 10ppb for Pt or 15ppb for 2E) to prevent the problem of negative weights in the kriging equation caused by zero grades. Replacement of the zero values with LDL values (correction) did not alter the global mean of the evaluation cut data. Table 11: Summary Indicating the Impact of Replacing Zero Values in the Datasets Mine Stillwater East Boulder Total Number of Data Points 41 655 9 948 Number of Data Points with Zero Values 6 375 106 Global 2E Mean Before Correction (opt) 0.683 0.595 Global 2E Mean After Correction (opt) 0.683 0.595 The length weighted composites of the evaluation cuts were subjected to statistical analysis initially by mine and by domain at each of Stillwater and East Boulder Mines. The domains for Stillwater and East Boulder Mines Mine are shown in Figure 9 and Figure 10. Due to sparsity of data at Boulder East and West domains were combined with Frog Pond West while Brass Monkey East and West domains were combined with Frog Pond East for the current evaluation. Therefore, estimation parameters for Frog Pond West were applied to the Boulder domains and parameters for Frog Pond East were applied to Brass Monkey blocks. Statistical data analysis of the composite data involved the construction of scatter plots of thickness vs. 2E grade to assess any correlation between them and histogram plots of grade (2E) to determine population distribution characteristics. Scatter plots of thickness vs. 2E grade generated using the composite data (Figure 28 and Figure 29) indicated no correlation between these variables but it was decided to estimate grades indirectly as grade-thickness accumulations in line with practice in the PGM sector. 77 Figure 28: Scatter plot of Composite UHW vs. 2E Grade for Stillwater Mine Figure 29: Scatter plot of Composite UHW vs. 2E Grade for East Boulder Mine R² = 0.0314 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 0 5 10 15 20 25 C o m p o si te 2 E G ra d e ( o p t) Undiluted Horizontal Width (ft) R² = 0.0254 0 0.5 1 1.5 2 2.5 3 0 5 10 15 20 25 C o m p o si te 2 E G ra d e ( o p t) Undiluted Horizontal Width (ft) 78 Histogram analysis of the 2E data (Figure 30 and Figure 31) revealed positively skewed distributions and outliers (anomalous values). Outliers tend to have undue influence on the overall estimates and, to minimise this influence, the outliers were dealt with using value capping during the estimation runs in Vulcan. Figure 30: Histogram Plot of Composite 2E Grades for Stillwater Mine Figure 31: Histogram Plot of Composite 2E Grades for East Boulder Mine 79 Capping was performed on 2E grade and the key variables evaluated, which are reef channel true width in feet (FCW), undiluted horizontal width in feet (UHW) and the grade-thickness accumulation termed feet ounces per ton (FOZPT) which is a product of FCW and 2E grade. Capping values for 2E utilised at Stillwater and East Boulder Mines which are presented in Table 12 were selected at the 98th percentile to align the modelled grades and actual grades observed at the mines during mining; capping was set at the 98th percentile for the Brass Monkey and Boulder blocks due to data sparsity. However, the Competent Persons acknowledge the impact the conservative capping values on masking the actual potential of the reef particularly at Stillwater Mine where the outlier grades are real and often associated with ballrooms. Ballrooms are localised areas of the reef containing anomalous quantities of PGMs and have a significant positive impact on the economics of mining the J-M Reef. Table 12: Capping Grades and Yield Limits Employed for the Mineral Resource Evaluation Mine Domain Capping Value at 98th Percentile UHW (ft) 2E (opt) FOZPT FCW (ft) Stillwater B 26.10 2.48 33.17 25.10 BW 15.90 2.47 17.70 15.00 DOWL 21.60 2.65 15.39 14.40 DOWU 21.60 1.74 11.52 14.60 OSEE 17.80 4.26 31.37 17.10 OSEW 17.00 3.99 26.74 15.20 OSW 18.00 3.92 28.79 15.80 UWE 17.60 3.26 19.08 13.10 BLK2-OSW 22.00 4.85 40.05 19.50 BLK2-UWE 22.40 3.99 26.20 17.30 East Boulder FPE 19.06 1.51 11.13 14.60 FPW 18.57 1.57 11.68 14.22 13.2.2.3 Geostatistical The composite FOZPT, UHW and FCW data was also subjected to geostatistical analysis in Supervisor to determine an appropriate estimation methodology and estimation parameters. The geostatistical analysis included the assessment of spatial trends in the composite FOZPT, UHW and FCW data and it was observed that these exhibit anisotropic behaviour (trends) as depicted in Figure 32 for FCW. Accordingly, normalised variograms were modelled for each the three variables per domain at Stillwater and East Boulder Mines and the variography results along strike for FOZPT and FCW which are relevant to the Mineral Resources are summarised in Table 13 and Table 14.
80 Figure 32: Spatial Analysis of FCW Continuity Table 13: Summary of Standardised Variogram Parameters for FOZPT Mine Domain Nugget Structure 1 Structure 2 Sill 1 Range 1 (ft) Range 2 (ft) Range 3 (ft) Sill 2 Range 1 (ft) Range 2 (ft) Range 3 (ft) Stillwater B 0.38 0.45 218 218 218 0.17 887 887 887 BW 0.44 0.41 204 204 204 0.15 921 921 921 OSWU 0.46 0.43 136 136 136 0.11 1 102 1 102 1 102 OSWL 0.46 0.43 136 136 136 0.11 1 102 1 102 1 102 OSEW 0.46 0.46 177 177 177 0.08 969 969 969 OSEE 0.44 0.38 146 146 146 0.18 1081 1081 1081 UWE 0.46 0.38 177 177 177 0.16 894 894 894 DOWL 0.43 0.5 180 180 180 0.07 853 853 853 DOWU 0.43 0.46 139 139 139 0.11 983 983 983 East Boulder FGE 0.42 0.49 134 112 51 0.09 952 820 179 FPW 0.42 0.49 134 112 51 0.09 952 820 179 Table 14: Summary of Standardised Variogram Parameters for FCW Mine Domain Nugget Structure 1 Structure 2 Sill 1 Range 1 (ft) Range 2 (ft) Range 2 (ft) Sill 2 Range 1 (ft) Range 2 (ft) Range 2 (ft) Stillwater B 0.38 0.45 180 180 180 0.17 887 887 887 BW 0.44 0.41 173 173 173 0.15 921 921 921 OSWU 0.46 0.43 136 136 136 0.11 1 102 1 102 1 102 OSWL 0.46 0.43 136 136 136 0.11 1 102 1 102 1 102 OSEW 0.46 0.48 146 146 146 0.06 1 102 1 102 1 102 OSEE 0.44 0.38 167 167 167 0.18 887 887 887 UWE 0.46 0.39 143 143 143 0.15 915 915 915 DOWL 0.43 0.48 245 245 245 0.09 1 112 1 112 1 112 DOWU 0.43 0.46 139 139 139 0.11 1 067 1 067 1 067 East Boulder FGE 0.39 0.48 127 94 44 0.13 839 640 94 FPW 0.39 0.48 127 94 44 0.13 839 640 94 The Qualified Persons are satisfied with the double structured variogram models of FOZPT and FCW constructed from the domain composite data as these indicate the achievement of second order stationarity, implying that grade estimation through simple or ordinary kriging interpolation is appropriate. The variograms indicate relatively high nugget to sill ratios, which need to be investigated further in future evaluations as nugget to sill ratios in the order of 10% to 20% have previously been 81 modelled from the available close spaced data. The variogram ranges indicated in Table 13 and Table 14 are typical of reef-type PGM deposits. Structural Modelling and Geological Loss Determination The evaluation cuts delineated through zone picking provide an outline of the potentially economic portions of the J-M Reef that can be modelled for reporting as Mineral Resources. Structural interpretation precedes 3D geological modelling of the economic part of the J-M Reef. Most of the major structures delineated at Stillwater and East Boulder Mines were identified from trenching and surface mapping or were interpreted from available aeromagnetic survey and drillhole data. Ongoing underground mapping and underground definition drilling generates additional closed spaced data used to refine the structural models at both mines. Structural interpretation by the Geologists and the Qualified Persons at both Stillwater and East Boulder Mines identified several major faults and intrusive dykes that intersect, offset or replace the J-M Reef in places. Geological structures of note are the regional South Prairie and Horseman Faults identified at Stillwater Mine. However, there are numerous other medium scale faults and dykes, which were modelled independently in Vulcan and Leapfrog for incorporation in the final geological model. The drillhole database contains standardised rock codes for dyke and fault intercepts, which are used to construct models for each geological structure. For the current evaluation, faults and dykes were digitised in Vulcan using available data and the geological structure outlines (polylines) were imported into the Leapfrog software environment where wireframes were constructed and projected the limits of the Mineral Resource footprint. Faults were modelled as planes in the 3D space using both drilling data and geological mapping information for the footwall lateral drifts, where possible. Dykes were modelled as 3D solids. The dyke and fault models were honoured during 3D modelling of the J-M Reef (Figure 33 to Figure 36). As a result, the 3D geological models of the reef already account for explicit geological losses. Additional geological losses were applied to tonnage estimates to account for possible losses due to unknown geological structures. The unknown geological structures (primarily dykes) were estimated from mine reconciliation data collected in the mined-out areas of Stillwater and East Boulder Mines. Unknown geological losses of 3.5% and 45.4% were applied to the tonnages estimates at Stillwater and East Boulder Mines, respectively. The Qualified Persons acknowledge that small-scale faults do not cause geological losses nor necessitate changes in mine designs as these are mined through by underground mining operations. As a result, unknown geological losses due to unidentified small-scale faults were not estimated. However, these faults present geotechnical and grade dilution challenges during mining and are, therefore, accounted for during detailed mine planning. Geological Interpretation and Wireframe Modelling The coded evaluation cut data was imported into Leapfrog for 3D geological block modelling and the data was desurveyed. Geological modelling of the reef channel was based on the “vein system” implicit wireframe modelling tool available in Leapfrog. The 3D geological modelling of the shape of 82 the reef channel was facilitated by the persistent continuity and regularity of the hangingwall contact of the J-M Reef package over most of the geological model footprints at Stillwater and East Boulder Mines. The wireframe models defining the reef channel limits allowed for conventional geological block modelling and grade estimation applicable to reef-type PGM deposits characterised by long range continuity of the orebody and PGM grades. Given the high intensity of localised thickness and grade variability of the J-M Reef and the data point density contrast between areas supported by both surface and underground definition drillhole data (eventually classified as Measured) and those supported by surface data only (eventually classified as Indicated or Inferred), it was decided build separate wireframe models for the two areas by domain. Wireframe models for the areas supported by surface data only were extended into adjacent undrilled areas where the reef is expected to occur and terminated at either a mining block boundary, surface topography wireframe model or a wireframe model for a major geological structure (e.g., the Horseman Fault at Stillwater Mine; Figure 33 and Figure 34). A topographic wireframe surface modelled using high- resolution airborne LIDAR survey data forms the up-dip limit of the reef channel 3D model. Figure 33: Illustration of Reef Channel Wireframe Model Terminated at a Fault at Stillwater Mine 83 Figure 34: Illustration of Reef Channel Wireframe Model Terminated at Dykes at East Boulder Mine
84 Figure 35: J-M Reef Geological and Structural Models for Stillwater Mine 85 Figure 36: J-M Reef Geological and Structural Models for East Boulder Mine 86 Block Modelling The varying strike, dip and mineralisation facies of the J-M Reef necessitated geological modelling and Mineral Resource estimation according to the domains at Stillwater and East Boulder Mines. Block modelling was carried out in Vulcan. Block models were built within the reef channel wireframe solids generated for each domain in Leapfrog. Block dimensions of 20ft x 20ft x reef channel width respectively in the X, Z and Y directions were used, with sub-blocking to 5ft x 5ft in the X and Z directions for accurate volume modelling in the plane of the J-M Reef (i.e., X-Z plane). The third dimension (Y plane) of each block is perpendicular to the reef plane. Block dimensions used were derived from a Kriging Neighbourhood Analysis (KNA), which indicated that block sizes of ranging from 3ft x 3ft x 3ft to 25ft x 25ft x 3ft can be used at the current data point spacing for the areas supported by surface and underground definition drillhole data without significantly changing the kriging efficiency and slope of regression of the estimates. Kriging efficiency and slope of regression are key metrics used to assess the quality of estimates. The KNA results also indicate that the block sizes can be increased to 200ft x 200ft in the X and Z directions in areas supported by surface drillhole data only. Data point spacing in the areas supported by surface and underground definition drillhole data ranges from less than 25ft to 100ft whereas the spacing ranges from 100ft to 1 000ft in remainder of the mines' footprints. Accordingly, the Qualified Persons propose a dual block size for the evaluation of the J-M Reef in future evaluations, with a smaller block size used in the well drilled areas and a larger block size used in the sparsely drilled areas. Grade and Tonnage Estimation Grade and Thickness Estimation FOZPT, UHW and FCW estimation in Vulcan was achieved through simple kriging interpolation of the respective composite data directly into the block models for each domain at both Stillwater and East Boulder Mines (Table 15). The simple kriging interpolation was based on a three-pass search and search parameters are summarised in Table 15 which were informed by the KNA and variography results summarised in Table 13 and Table 14. The radii for the first search were aligned to the variogram ranges whereas the search radii for the second searches were set at 1.8 the variogram range for the relevant variable and domain at Stillwater and 1.5 and 1.7 times the variogram range for the relevant variable and domain at East Boulder Mine. The third search radii set at 10 times the variogram range for the relevant variable and domain at both mines. The minimum number of samples was lowered to four and three respectively for Stillwater and East Boulder Mines when estimating footwall zones that sparse data. The three-pass search strategy ensured interpolation of FOZPT, UHW and FCW into all blocks, estimates at longer search radii completed lower levels of confidence than for the first search. Accordingly, search distance and number of samples informing an estimate were included in the Mineral Resource classification scheme. Due to the simple kriging interpolation technique used which requires a reference mean to guide the interpolation process, it was necessary to determine domain mean values for FOZPT, UHW and FCW. Domain global means were calculated for each domain from declustered capped data for the 87 relevant variable and at different panel sizes ranging from 10ft to 600ft with an increment of 10ft in Datamine. This created 6000 interactions and the iteration that provided the lowest mean value was selected as the domain mean for the relevant variable. The domain global means for FOZPT, UHW and FCW employed for simple kriging are presented in Table 16. Table 15: Search Parameters Employed for Grade Estimation Search Reference Number of Samples Description of Area Minimum Maximum First Search 16 34 Close spaced data points Second Search 10 20 Sparse data points Third Search 10 20 Very Sparse data points Table 16: Domain Global Means Calculated from Declustered Data Mine Description of Area Domain UHW (ft) FOZPT FCW (ft) Stillwater Measured and Indicated B 4.54 3.20 4.42 BW 3.28 2.11 2.98 DOWL 5.60 2.70 3.80 DOWU 5.74 2.51 3.79 OSEE 3.86 4.49 3.75 OSEW 4.02 4.00 3.66 OSW 4.13 4.38 3.66 UWE 3.95 2.86 3.07 WFE 5.52 2.27 3.54 WFW 5.52 2.27 3.54 Stillwater Inferred B 4.66 2.69 4.14 BW 2.82 0.95 2.10 DOWL 5.50 2.33 3.61 DOWU 5.55 2.20 3.47 OSEE 3.22 3.00 3.12 OSEW 3.69 3.06 3.18 OSW 3.59 3.23 3.11 UWE 3.56 2.12 2.69 WFE 5.52 2.27 3.54 WFW 5.52 2.27 3.54 BLK2-OSW 1.43 0.36 1.31 BLK2-UWE 1.43 0.36 1.31 East Boulder All Areas BME 5.15 2.28 3.95 BMW 5.15 2.28 3.95 BOE 6.43 3.18 4.93 BOW 6.43 3.18 4.93 FPE 5.15 2.28 3.95 FPW 6.43 3.18 4.93 After simple kriging interpolation of FOZPT, UHW and FCW into the block models, 2E grades were calculated by dividing the modelled FOZPT with FCW per block. Figure 37 and Figure 38 depict the modelled 2E grades contained the block models for Stillwater and East Boulder Mines.
88 Figure 37: Modelled 2E Grades and Classification for Stillwater Mine 89 Figure 38: Modelled 2E Grades and Classification for East Boulder Mine 90 Block Model Validation The Qualified Persons validated the geological block models for each domain by comparing 2E mean grades of the capped composite data and the modelled 2E mean grades as shown in Table 17. The estimates were also validated through spot checks of composite data and block model grades displayed along drillhole sections and on level plans. Table 17: Comparison of the Estimated and Evaluation Cut Composite Grades Mine Domain Mean 2E Grade (opt) Difference (%) Composite Data Estimate - Simple Kriging Stillwater DOWU 0.656 0.648 1.22% DOWL 0.739 0.727 1.62% UWE 0.883 0.799 9.51% OSW 1.125 1.031 8.36% OSEW 1.049 1.02 2.76% OSEE 1.125 1.067 5.16% BW 0.782 0.639 18.29% B 0.853 0.78 8.56% East Boulder FPE 0.598 0.578 3.34% FPW 0.645 0.643 0.31% The comparisons revealed that the 2E means of capped composite data are higher than those for the model results for all domains reflecting an overall conservativeness in the estimation approach. This is more apparent in the Blitz, Blitz West, Off Shaft-East-East, Off Shaft-West and Upper West-East at Stillwater Mine where the modelled results were 5.16% to 18.29% lower than the composite mean 2E grades. This is additional to the grade capping which is conservative measure that limits the undue influence of localised high-grade samples on the overall estimates. The localised high grades are associated with ballrooms. Historical experience from production reconciliation indicates that more metal contents than estimated is recovered during mining at Stillwater Mine. From the spot checks of the distribution of estimated grades within the block models against uncapped composite data along section lines (swath analysis; Figure 39 and Figure 40) and on level plans drill sections, the Qualified Persons also noted overall alignment between the block estimates and composite grades. However, global means tend to have significant influence in the estimates for sparsely drilled areas categorised as Indicated or Inferred which is an attribute of the simple kriging interpolation method. The impact of grade capping was noticeable in the Off Shaft area, where there is a high occurrence of ballrooms and outlier grades. The East Boulder Mine Competent Person for Mineral Resources also noted the sharp grade change at the domain boundary separating Frog Pond East and Frog Pond West. Although the grade change appears to be an unnatural transition, the overall picture best reflects the overall grades in each of the domains given the grade interpolation used. Despite the potential understating of 2E grades which is more pronounced at Stillwater Mine (Off Shaft) than at East Boulder Mine and the unnatural grade change across the domain boundary at East Boulder Mine, the Qualified Persons are satisfied with the congruency in 2E grades between the base composite data and the modelled grades. Accordingly, the block models constitute a credible basis for Mineral Resource reporting. 91 Figure 39: Blitz Mean 2E Grade (opt) by Easting Figure 40: Frog Pond East Mean 2E Grade (opt) by Easting
92 Tonnage Estimation A tonnage factor of 11.3ft3/ton (equivalent to a density of 0.088 ton/ft3) was applied to the block model volumes to derive tonnage estimates for Stillwater and East Boulder Mines. The tonnage factor is an average of the available RD data accumulated since 2017 at both Stillwater and East Boulder Mines. The Qualified Persons recommend continued RD determinations to expand the RD dataset which would permit the modelling of density and density weighting of the composite data to further improve the accuracy of the tonnage and grade estimates. The tonnage estimates for Stillwater and East Boulder Mines were discounted by the application geological loss factors of 3.5% and 5.4%, respectively. Mineral Resource Classification Mineral Resources were classified as Inferred, Indicated or Measured depending on increasing levels of geoscientific knowledge and confidence. Drillhole data quality is similar across all Mineral Resource classes as the entire database was subjected to common rigorous validations, which enabled the identification of spurious data and its remediation or exclusion from the evaluation database. Therefore, data quality was not a contributing factor in the classification of the Mineral Resources. However, the localised thickness and grade variability of the J-M Reef is a major source of uncertainty in the estimates. Considering the long-range continuity and the high localised thickness and grade variability of the J-M Reef, diamond core drillhole spacing and proximity to areas that have been or are being mined (where reef characteristics have been confirmed from underground exposures and ore processing), were the main variables influencing the Qualified Persons' assessment of level of geoscientific knowledge and confidence in the J-M Reef mined at Stillwater and East Boulder Mines. Furthermore, the Qualified Person also considered the quality of estimates, which is highest for the estimates obtained by the first search and lowest for the estimates obtained by the third search. In general, the classification criteria ensured that surface diamond drillhole data is only sufficient for the assessment and classification of Mineral Resources as either Indicated or Inferred and that no Measured Mineral Resources were classified based on surface drillhole data only. There are uncertainties in the thickness and grades due to high localised variability and, as a result, grade and tonnage estimates for these areas were influenced by the domain global means. The Qualified Persons support the use of domain means as these reduce the uncertainty in the tonnage and grade estimates caused by the high localised variability of the J-M Reef. The Qualified Persons employed the following criteria for the Mineral Resource classification: • Measured: The 50ft drill station spacing (i.e., <25ft to 100ft drillhole data point spacing) represents the optimal drillhole spacing that provides sufficient data for the achievement of the highest level of geoscientific knowledge and confidence in the geological and grade continuity of the J-M Reef. Accordingly, the Mineral Resources delineated through underground definition drilling and quantified at a high level of confidence through geological block modelling were classified as Measured. As a result, estimates in these areas were obtained from the first search. Furthermore, these areas are situated close to mined out areas or areas that are currently being mined where capital infrastructure has already been or is currently being established. Reef characteristics in Measured areas are well-known from drilling, mining and ore processing. In addition, the level of geoscientific knowledge and confidence in the J-M Reef in such areas permits detailed mine planning and stope economic evaluation. Errors due to uncertainties in grade, thickness and 93 tonnages do not materially affect the economic viability of extracting the material classified as Measured; and • Indicated and Inferred: Typical drillhole spacing in the Indicated or Inferred areas ranges from 100ft to 1 000ft. Estimates in classified as Indicated were informed by a second search whereas those for Inferred areas were obtained from a third search. The level of geoscientific knowledge and confidence in the areas classified as Indicated permits the scheduling of the Mineral Resources in a mine plan and the planning of capital infrastructure and high-level stope outlines, and assessment of the economic viability of the mining the scheduled material. The uncertainties in grades and thickness of the J-M Reef and domain boundaries as well as the long distances from established mining infrastructure prevent accurate planning of capital infrastructure and stope outlines in the areas classified as Inferred. The Qualified Persons diligently applied these criteria for the classification of Mineral Resources for Stillwater and East Boulder Mines. The Mineral Resource classification outcomes for Stillwater and East Boulder Mines are depicted in Figure 37 and Figure 38, respectively. The Qualified Persons support and approve the disclosure of the Inferred, Indicated and Measured Mineral Resources for Stillwater and East Boulder Mines. Cut-off Grades, Technical Factors and Reasonable Prospects for Economic Extraction Prospects for Eventual Economic Extraction Assessment The Qualified Persons considered the prospects for economic extraction of the J-M Reef within the footprints of Stillwater and East Boulder Mines prior to the declaration of the Mineral Resources. This assessment benefited from the fact that a significant proportion of the Mineral Resources has been included in the LoM production schedules for Stillwater and East Boulder Mines, which were derived from detailed scheduling and subjected to economic tests using reasonable economic parameters and forecasts. The Qualified Person have confirmed that all the Mineral Resources have been delineated within the Stillwater and East Boulder Mines footprints over which Sibanye-Stillwater is legally permitted to mine the J-M Reef. The location, quantity, grade, continuity and other geological characteristics and geotechnical parameters of the J-M Reef in these areas are well-understood from extensive diamond drilling and laboratory analysis of the mineralised intersections, geological modelling, mining and ore processing. The Qualified Persons considered it reasonable to assume that the Mineral Resources located outside of the current LoM plan footprints will be mined and processed in the future using similar underground mining methods and conventional flotation ore processing technology to those employed at the current operations. In addition, some of the major mining infrastructure already established at the two mining complexes (e.g., access and hoisting shafts, underground services infrastructure, powerlines, bulk water pipelines and mine access roads) will be used for future mining operations as the LoM capital budgets continue to provide for maintenance of this infrastructure. Sibanye-Stillwater has continued to fulfil the regulatory requirements that have enabled it to retain the mineral title for PGMs as well as the environmental and social permits required for the mining and ore 94 processing operations at Stillwater and East Boulder Mines and mineral beneficiation operations at the Columbus Metallurgical Complex. As a result, the Qualified Persons consider it likely that Sibanye- Stillwater will be able to obtain regulatory approvals and permits to retain its mineral title and to continue mining the mineralisation included in the Mineral Resource estimates. Owing to consideration of prospects for economic extraction, the J-M Reef mineralisation within a 50ft pillar from surface which cannot be mined was excluded from the Mineral Resources for Stillwater and East Boulder Mines. Sibanye-Stillwater has a marketing strategy in a place for its products which is based on historical experience, long term supply agreements and market research on commodity demand, supply and prices which are utilised for business planning. Mining parameters, production schedules, metallurgical parameters, capital and mining and ore processing operating costs employed for assessing prospects for economic extraction (mine planning) are based on historical experience at the current operations and research-based forecasting. The Qualified Persons conclude that there are no apparent material risks that would prevent the economic extraction of the J-M Reef mineralisation included in the Mineral Resource estimates for Stillwater and East Boulder Mines, and the disclosure of the Mineral Resource estimates is appropriate. Cut-off Grades and Minimum Mining Width The Mineral Resources for Stillwater and East Boulder Mines are reported at a minimum width cut-off (minimum mining width) of 7.5ft and 2E grade cut-offs of 0.20opt (6.86g/t) and 0.05opt (1.71g/t ) at Stillwater and East Boulder Mines, respectively. Over 80% of stopes at Stillwater and East Boulder Mines are mined through the mechanised cut and fill method. For Mineral Resource evaluation, the Qualified Persons determined a minimum mining width of 7.5ft by considering the operating envelopes of a 2-yard load haul dumper (LHD), which is the most representative equipment for the mechanised cut and fill method, and the steep dips of the J-M Reef. In areas of the J-M Reef where the modelled reef channel thickness is narrower than 7.5ft, an appropriate dilution was added to achieve the required minimum mining width, which had the impact of lowering grades in these areas. Then, the relevant 2E grade cut-offs were applied to block models for Stillwater and East Boulder Mines resulting in the exclusion of certain low-grade parts of the J-M Reef. For the determination of the 2E grade cut-off for Mineral Resource reporting, the Qualified Persons considered the minimum 2E grade required to cover the total cost for the extraction of PGMs (i.e., combined mining, ore processing and refining costs) in a ton of mineralised material of the J-M Reef. This assessment also considered available materials hoisting and plant capacities, metallurgical recoveries, and the reef continuity that enables achievement of the targeted production efficiencies while optimising net present value (NPV) and Mineral Resource recovery. For the grade cut-off calculation, the historical costs for East Boulder Mine were used as these reflect steady state operating costs whereas historical costs for Stillwater Mine are higher as the mine is still ramping up production to achieve steady state production levels in FY2027. 95 The Qualified Persons also utilised the forecast Pd and Pt metal prices provided by Sibanye-Stillwater, which have been used for corporate planning and are presented in Table 18. In line with industry practice, Sibanye-Stillwater’s forward-looking price assumptions for Mineral Resource reporting are 10% higher than the three-year trailing-average prices used for Mineral Reserve reporting as they focus on longer timeframes than Mineral Reserves and are intended to better capture the long-term but still reasonable prospect for economic extraction. These prices are expected to stay stable for at least three to five years unless if there is a fundamental, perceived long-term shift in the market. In forecasting the prices, Sibanye-Stillwater also considered its view of the market for PGMs. The Qualified Persons reviewed the economic parameters provided by Sibanye-Stillwater and found them to be reasonable for Mineral Resource estimation and reporting. Table 18: Parameters Employed for Cut-off Grade Calculation and Mineral Reserve Declaration Item Units East Boulder Stillwater Pt Pd Pt Pd Mineral Resource-Mineral Reserve Cut-off Price US$/oz 1 500 1 500 1 500 1 500 Business Planning and Mineral Reserve Declaration Price US$/oz 1 250 1 250 1 250 1 250 J-M Reef Pd:Pt Ratio 1.00 3.60 1.00 3.51 Total Recovery % 92.6 89.7 91.2 93.5 Total Operating Cost $/t milled 275.50 410.23 Total Processing, Smelting and Refining Cost $/t milled 49.97 69.97 J-M Reef Minimum 2E Grade (High Grade Only) opt 0.22 0.32 J-M Reef Minimum 2E Grade (Incremental Cost) opt 0.04 0.06 Overall 2E Cut-off Grade Used opt 0.05 0.20 Using the parameters in Table 18 provided by Sibanye-Stillwater, the Qualified Person initially determined the minimum 2E grades required to pay for the extraction and processing of a ton of high-grade ore at East Boulder Mines of 0.23opt. This scenario excludes low grade (0.05-0.23opt) material which is inevitably mined to access the high-grade material. The cost of mining of this low-grade material is already accounted for in the mining cost for high grade material. Furthermore, there is sufficient hoisting and milling capacity for the processing of the mined low-grade material without displacing any high- grade material. Historically, this low-grade material has been mined and milled profitably together with the high-grade material and together these materials constitute the run of mine ore (RoM) reported as Mineral Reserves. Using the incremental cost of hoisting and processing the low-grade material, the Qualified Person determined an indicative 2E minimum grade of approximately 0.04opt (Table 18). Since all the material grading at least 0.05opt is processed at East Boulder Mine, the Qualified Person considered a 2E cut-off grade of 0.05opt to be appropriate for Mineral Resource reporting and this matches the cut-off grade employed for Mineral Reserve reporting at East Boulder Mine. Applying the same grade cut-off calculation logic to Stillwater Mine, an indicative minimum 2E grade of 0.34opt was obtained for the mining and processing of high-grade ore while a minimum 2E grade of 0.06opt was determined under the incremental cost scenario. The higher grades reflect the current production ramp-up associated with higher operating costs than those for East Boulder Mine. Due plant capacity constraints, Stillwater Mine is expected to mill material above 0.20opt and the mined low- grade material will not be hoisted to surface. Accordingly, the 2E cut-off grade of 0.20opt, which is applicable for the mining and processing of high-grade ore, was used for Mineral Resource reporting at
96 Stillwater Mine and this is also the cut-off grade used for Mineral Reserve reporting. While a higher 2E cut-of grade has been used for reporting the Mineral Resources at Stillwater Mine, the Qualified Person consider it more appropriate and therefore recommends the reporting of Mineral Resource at the 2E cut-off grade of 0.05opt at both mines as this more fully reflects the Mineral Resource potential of the J- M Reef than the 0.20opt used at Stillwater Mine which is driven by plant capacity constraints. Mineral Resource Estimates The Mineral Resource estimates for Stillwater and East Boulder Mines as at the end of the fiscal year ended December 31, 2021 are summarised in Table 19 and Table 20. The Mineral Resource estimates in Table 19 are reported inclusive of Mineral Reserves while the estimates in Table 20 are reported exclusive of Mineral Reserves. These estimates are in situ estimates of tonnage and grades (point of reference) reported at a minimum mining width of 7.5ft, which is applicable for the Ramp and Fill underground mining method dominant at Stillwater and East Boulder Mines. Furthermore, the Mineral Resources are reported at 2E cut-off off grades of 0.20opt (6.86g/t) and 0.05opt (1.71g/t) at Stillwater and East Boulder Mines, respectively. Individual metal grades are based on prill splits (metal ratio) data routinely collected at the concentrators, which are summarised in Table 41. No metal equivalents are reported as these are irrelevant to Stillwater and East Boulder Mines . Table 19: Mineral Resource Estimates Inclusive of Mineral Reserves at the End of the Fiscal Year Ended December 31, 2021 Based on Pd and Pt Price of $1 500/oz Description Mineral Resources Inclusive of Mineral Reserves Imperial Category Mine Tons (Million) Pd (opt) Pt (opt) 2E (opt) 2E Content (Moz) Measured Stillwater 24.0 0.35 0.10 0.46 10.9 East Boulder 20.0 0.31 0.09 0.40 7.9 0 Subtotal/Average 44.0 0.33 0.09 0.43 18.9 Indicated Stillwater 34.5 0.32 0.09 0.41 14.3 East Boulder 30.6 0.30 0.08 0.39 11.8 Subtotal/Average 65.1 0.31 0.09 0.40 26.1 Measured + Indicated Stillwater 58.5 0.34 0.10 0.43 25.2 East Boulder 50.6 0.31 0.08 0.39 19.8 Subtotal/Average 109.1 0.32 0.09 0.41 45.0 Inferred Stillwater 67.7 0.28 0.08 0.35 24.0 East Boulder 57.5 0.28 0.08 0.36 20.6 Subtotal/Average 125.2 0.28 0.08 0.36 44.6 Metric Category Mine Tonnes (Million) Pd (g/t) Pt (g/t) 2E (g/t) 2E Content (Moz) Measured Stillwater 21.7 12.16 3.46 15.63 10.9 East Boulder 18.1 10.66 2.96 13.62 7.9 Subtotal/Average 39.9 11.48 3.23 14.71 18.9 Indicated Stillwater 31.3 11.06 3.15 14.22 14.3 East Boulder 27.8 10.38 2.88 13.26 11.8 Subtotal/Average 59.1 10.74 3.03 13.77 26.1 Measured + Indicated Stillwater 53.0 11.51 3.28 14.79 25.2 East Boulder 45.9 10.49 2.91 13.40 19.8 Subtotal/Average 99.0 11.04 3.11 14.15 45.0 Inferred Stillwater 61.5 9.45 2.69 12.14 24.0 East Boulder 52.2 9.61 2.67 12.28 20.6 Subtotal/Average 113.6 9.52 2.68 12.21 44.6 97 Description Mineral Resources Inclusive of Mineral Reserves Imperial Category Mine Tons (Million) Pd (opt) Pt (opt) 2E (opt) 2E Content (Moz) 2E Cut-off Grade Stillwater Mine – 0.20opt (6.86g/t) 2E Cut-off Grade East Boulder Mine – 0.05opt (1.71g/t) Pd Price – $1 500/oz Pt Price – $1 500/oz 2E Recovery Stillwater Mine – 92.3% 2E Recovery East Boulder Mine – 91.0% Pd:Pt Ratio Stillwater Mine – 3.51:1 Pd:Pt Ratio East Boulder Mine – 3.60:1 Table 20: Mineral Resource Estimates Exclusive of Mineral Reserves at the End of the Fiscal Year Ended December 31, 2021 Based on Pd and Pt Price of $1 500/oz Description Mineral Resources Exclusive of Mineral Reserves Imperial Category Mine Tons (Million) Pd (opt) Pt (opt) 2E (opt) 2E Content (Moz) Measured Stillwater 8.7 0.34 0.10 0.44 3.8 East Boulder 8.0 0.31 0.09 0.40 3.1 Subtotal/Average 16.6 0.33 0.09 0.42 6.9 Indicated Stillwater 9.9 0.33 0.09 0.43 4.2 East Boulder 12.1 0.30 0.08 0.38 4.6 Subtotal/Average 22.0 0.31 0.09 0.40 8.8 Measured + Indicated Stillwater 18.6 0.34 0.10 0.43 8.0 East Boulder 20.0 0.30 0.08 0.38 7.7 Subtotal/Average 38.6 0.32 0.09 0.41 15.7 Inferred Stillwater 67.7 0.28 0.08 0.35 24.0 East Boulder 57.5 0.28 0.08 0.36 20.6 Subtotal/Average 125.2 0.28 0.08 0.36 44.6 Metric Category Mine Tonnes (Million) Pd (g/t) Pt (g/t) 2E (g/t) 2E Content (Moz) Measured Stillwater 7.9 11.68 3.33 15.00 3.8 East Boulder 7.2 10.61 2.95 13.55 3.1 Subtotal/Average 15.1 11.16 3.14 14.31 6.9 Indicated Stillwater 9.0 11.35 3.23 14.58 4.2 East Boulder 10.9 10.14 2.81 12.95 4.6 Subtotal/Average 19.9 10.68 3.00 13.68 8.8 Measured + Indicated Stillwater 16.9 11.50 3.28 14.78 8.0 East Boulder 18.2 10.32 2.87 13.19 7.7 Subtotal/Average 35.0 10.89 3.06 13.95 15.7 Inferred Stillwater 61.5 9.45 2.69 12.14 24.0 East Boulder 52.2 9.61 2.67 12.28 20.6 Subtotal/Average 113.6 9.52 2.68 12.21 44.6 2E Cut-off Grade Stillwater Mine – 0.20opt (6.86g/t) 2E Cut-off Grade East Boulder Mine – 0.05opt (1.71g/t) Pd Price – $1 500/oz Pt Price – $1 500/oz 2E Recovery Stillwater Mine – 92.3% 2E Recovery East Boulder Mine – 91.0% Pd:Pt Ratio Stillwater Mine – 3.51:1 Pd:Pt Ratio East Boulder Mine – 3.60:1 The Qualified Persons with responsibility for reporting and sign-off of the Mineral Resources for Stillwater and East Boulder Mines are Jeff Hughs and Jennifer Evans, respectively. Jennifer and Jeff are Professional Geologists with more than five years of experience relevant to the estimation and reporting of Mineral Resources and mining of the J-M Reef at Stillwater and East Boulder Mines. 98 MINERAL RESERVE ESTIMATES Mineral Resource to Mine Reserve Conversion Methodology Mineral Resources Available for Conversion Prior to commencing the planning process at Stillwater and East Boulder Mines, the first stage was to define the Mineral Resources available for conversion to Mineral Reserves – these being Indicated and Measured Mineral Resources. The Mineral Resource model identified the tonnages, grades and 2E content available for conversion. Mineral Reserve Estimation Methodology Mineral Reserves for Stillwater and East Boulder Mines were prepared from a business and LoM planning process which converted Indicated and Measured Mineral Resources to Mineral Reserves. The Mineral Reserves were classified using criteria set out in Section 14.2. The conversion took into consideration all the modifying factors for the various disciplines relevant to Mineral Reserves, namely mining methods, mining and surveying factors, ore processing and metallurgical recoveries, infrastructure engineering and equipment, market conditions, environmental and social matters, and capital and operating costs (Section 14 to 20). The LoM plan production schedules generated were tested for economic viability using a set of reasonable economic parameters prior to the declaration of Mineral Reserves (Section 21). Despite the common estimation methodology employed for Indicated and Measured Mineral Resources, different approaches were followed for the scheduling of Indicated and Measured Mineral Resources to derive the LoM production schedules underpinning the Mineral Reserves for Stillwater and East Boulder Mines (Section 15.7). This is due to different levels of confidence between the Mineral Resource classes resulting from different drillhole data point spacing given the high microvariability of the J-M Reef. Scheduling of the Measured Mineral Resources and conversion to Proved Mineral Reserves benefitted from the high abundance of geological information available to accurately constrain thickness, tonnage and grades. However, the scheduling of the Indicated Mineral Resources and conversion to Probable Mineral Reserves relied on statistics and key metrics extrapolated from the Proved Mineral Reserve areas per domain and mining block. The Mineral Reserves were estimated for each of the sub-areas at both Stillwater Mine and East Boulder Mines. The conversion of Mineral Resources to Mineral Reserves at the mines follows a methodology that was developed in 1990 and adjusted as required over the years as more geological and mining information became available. The methodology accounts for the different reef facies and the sub- areas that exist at the mines and the fact that a single set of parameters within a sub-area can be used to confidently project surface and underground drilling for Mineral Resource estimates. Mining experience and reconciliation between Mineral Reserve estimates and actual production figures have demonstrated the robustness of the methodology in making estimates of tonnages and ounces that have historically been reported as Mineral Reserves. 99 The following key technical parameters, assumptions and mining modifying factors were utilised to develop the mine designs and LoM production schedules as discussed in Section 14: • Cut-off grade; • Percentage ore recovered; • Geotechnical and geohydrological considerations; • Mining method and applicable minimum mining widths; • Dilution (planned and unplanned overbreak); • Deletion; • Extraction rate; • Extraction sequence; • Planned productivity; • Equipment and personnel equipment requirements; and • Fill requirements (type and quantity). The LoM planning and subsequent production scheduling was developed utilising historical productivity parameters inclusive of the following: • Stoping tons per miner per month per mining method; • Ore tons generated per foot of footwall development; • Primary development productivities, feet advance per month; and • Secondary development productivities, feet advance per month; Historical analysis of mine planning and production data revealed that a recovery factor of 75% was required to reconcile blasted and removed tons in the sub-level extraction stopes. Therefore, a 75% recovery factor was applied to all sub-level extraction tons and ounces to Mineral Reserves. Initially, scheduling included all primary development (footwall lateral drifts) to access the stope blocks in the Measured Mineral Resource areas. Thereafter, the development design and scheduling were extended into the Indicated Mineral Resource areas where primary annual development rates were derived through the utilisation of historical ratios. The scheduling of the stoping was dependent on the completion of the footwall access and the necessary diamond drilling to form an outline of the stopable areas in terms of grade and tonnage. In addition, the scheduling was also dependent on the mill feed requirements. On the completion of the lateral development schedule, the starting dates for the development of the stoping blocks were defined based on when access will be attained and the mines’ requirements in terms of RoM ore production. It is also during this process that the true width was corrected for dip and a minimum mining width was applied dependant on mining method and type of equipment to be employed. For each stope block, a proposal (business plan) was drawn up which included, amongst other information, primary and secondary development requirements, reef widths, tonnage and forecasted grade, expected percentage ore recovery, applied cut-off grades, overall stope design, mining method to be employed, ventilation requirements, backfill requirements extraction sequence, and manpower and mining equipment requirements.
100 Once the technical inputs were defined, each stope block was subjected to an economic test. This economic test used technical and financial parameters to determine the economic viability of the planned stoping operations. It accounted for all costs associated with the ore extraction and balanced the total costs against the revenue generated by the block. From the process, a NPV of the planned stope was determined. Where required (e.g., if a stope does not meet the required financial returns), the stope was optimised to return the best value. The tonnage and grades in the LoM production schedules were aggregated to derive Mineral Reserve tons and grades, with the tonnage and grades scheduled in the Measured Mineral Resources supported by definition drillhole data classified as Proved and those in the Indicated and Measured Mineral Resources supported by surface drillhole data but no definition drillhole data classified as Probable. The Qualified Person can confirm that the process followed to convert the Measured Mineral Resources into Proved Mineral Reserves was based on historical performance and reconciliations, with input and outputs reported within the accuracy level of ±15%. The process followed to convert the Indicated and Measured Mineral Resources to Probable Mineral Reserves utilised statistics from the Proved Mineral Reserves and a geological block model at a lower level of confidence resulting in the outputs reported within ±25% accuracy. Point of Reference The aggregated scheduled tonnages and grades reflected in the LoM production schedules and delivered to the concentrators for processing at Stillwater and East Boulder Mines are the tonnage and grade estimates reported as the Mineral Reserve estimates. Therefore, the mill head is the point of reference for Mineral Reserve reporting. Cut-off Grades The 2E cut-off grade for Mineral Reserve reporting is 0.20opt for Stillwater Mine and 0.05opt for the East Boulder Mine. All diluted blocks within the individual stope outlines that are above the cut-off grade were included in the Mineral Reserves. The 2E cut-off grade was selected as the optimal cut-off grade that ensures continuity of the mineable portions of the reef and enables achievement of targeted production efficiencies while optimising NPV. Using the parameters in Table 18, the Qualified Person determined the minimum 2E grades required to pay for the extraction and processing of a ton of high-grade ore at Stillwater and East Boulder Mines of 0.34opt and 0.23opt, respectively. This approach leaves the mined low-grade material underground, which would be inappropriate if there is unused hoisting and ore processing plant capacities. As a result, the Qualified Person also determined the 2E cut-off grades based on the incremental cost of hoisting and processing low-grade material inevitably mined to access the high-grade ore. The resulting minimum 2E grades determined are 0.06opt and 0.04opt for Stillwater and East Boulder Mines, respectively. 101 As the low-grade (0.05opt to 0.20opt 2E) material being economically mined and milled together with the high-grade material (greater than 0.20opt 2E) at East Boulder Mine, the Qualified Person elected to use 0.05opt as the 2E cut-off grade for Mineral Reserve reporting. This is aligned to the minimum 2E grade derived through consideration of the incremental cost of hoisting and processing and the current practice of milling RoM ore comprising high-grade and low-grade material. Unlike at East Boulder Mine where there is sufficient hoisting and ore processing capacity to process both the high-grade and low-grade material at steady state, Stillwater Mine will have processing capacity to process high-grade material only at steady state. As a result, the Qualified Person deemed it inappropriate to derive a 2E cut-off grade on the incremental cost basis. The Qualified Person also noted that the Stillwater Mine is still ramping up production and its current operating costs exceed steady state operating costs. Due to mill capacity constraints which necessitates the processing of high- grade ore only from FY2027 onwards for the remainder of the LoM, the Qualified Person considered it prudent to use a 2E cut-off grade of 0.20opt for reporting of Mineral Reserves for Stillwater Mine. This is aligned to the minimum 2E grade calculated for the mining and processing of high-grade ore only at East Boulder using steady state operating costs. Mineral Reserve Classification Criteria The tonnage and grades in the LoM production schedules were aggregated to derive Mineral Reserve tons and grades. The tonnage and grades scheduled in the Measured Mineral Resource areas where there is definition drillhole data were classified as Proved Mineral Reserves. The tonnage and grades scheduled in the Measured and Indicated Mineral Resources where there is no definition drillhole data were classified as Probable Mineral Reserves. The Qualified Person can confirm that the process followed to convert the Measured Mineral Resources into Proved Mineral Reserves is based on historical performance and reconciliations, with input and outputs reported within the accuracy level of ±15%. The process followed to convert the Indicated Mineral Resources to Probable Mineral Reserves utilised statistics from the Proved Mineral Reserves and a geological block model at a lower level of confidence and, as a result, the outputs are reported within ±25% accuracy. Mineral Reserve classification maps for Stillwater and East Boulder Mines are shown in Figure 41 and Figure 42 respectively. 102 Figure 41: Mineral Reserve classification for Stillwater Mine 103 Figure 42: Mineral Reserve classification for East Boulder Mine
104 Mineral Reserve Estimates The Mineral Reserve estimates for Stillwater and East Boulder Mines as at December 31, 2021 are reported in Table 21. Only the Measured and Indicated portions of the Mineral Resources within the LoM plans have been included in the Mineral Reserve. No Inferred Mineral Resources have been included in Mineral Reserve estimates. The reference point for tonnage and grade estimates for the Mineral Reserve estimates is the mill head and the Mineral Reserve estimates are reported at the 2E cut-off grade of 0.20opt (6.86g/t) and 0.05opt (1.71g/t) at Stillwater and East Boulder Mines, respectively. The tonnages and 2E grades indicate the expected RoM ore tonnages and grades derived through LoM production scheduling. Individual metal grades are based on the application of prill splits (metal ratios) which are summarised in Table 41 and were determined from actual data routinely collected at the Stillwater and East Boulder Concentrators. The Qualified Person with responsibility for reporting and sign-off of the Mineral Reserves for Stillwater and East Boulder Mines is Justus Deen. The Qualified Person is a Registered Mining Engineer with more than five years of experience relevant to the estimation and reporting of Mineral Reserves and mining of the J-M Reef at Stillwater and East Boulder Mines. Table 21: Mineral Reserve Estimates Inclusive of Mineral Reserves at the End of the Fiscal Year Ended December 31, 2021 Based on Pd and Pt Price of $1 250/oz Description Mineral Reserves Imperial Category Mine Tons (Million) Pd (g/t) Pt (g/t) 2E (opt) 2E Content (Moz) Proved Stillwater 5.1 0.39 0.11 0.50 2.6 East Boulder 3.9 0.30 0.08 0.38 1.5 Subtotal/Average 9.0 0.35 0.10 0.45 4.1 Probable Stillwater 39.4 0.27 0.08 0.35 13.7 East Boulder 26.8 0.28 0.08 0.36 9.6 Subtotal/Average 66.3 0.27 0.08 0.35 23.2 Proved + Probable Stillwater 44.6 0.28 0.08 0.36 16.2 East Boulder 30.7 0.28 0.08 0.36 11.1 Total/Average 75.3 0.28 0.08 0.36 27.3 Metric Category Mine Tonnes (Million) Pd (g/t) Pt (g/t) 2E (g/t) 2E Content (Moz) Proved Stillwater 4.6 13.42 3.82 17.25 2.6 East Boulder 3.5 10.16 2.82 12.98 1.5 Subtotal/Average 8.2 12.02 3.39 15.41 4.1 Probable Stillwater 35.8 9.24 2.63 11.87 13.7 East Boulder 24.3 9.59 2.66 12.26 9.6 Subtotal/Average 60.1 9.38 2.64 12.03 23.2 Proved + Probable Stillwater 40.4 9.72 2.77 12.49 16.2 East Boulder 27.9 9.67 2.68 12.35 11.1 Total/Average 68.3 9.70 2.73 12.43 27.3 2E Cut-off Grade Stillwater Mine – 0.20opt (6.86g/t) 2E Cut-off Grade East Boulder Mine – 0.05opt (1.71g/t) Business Planning and Mineral Reserve Declaration Pd and Pt Price – $1 250/oz Cut-off Determination Pd Price – $1 250/oz Cut-off Determination Pt Price – $1 250/oz 2E Recovery Stillwater Mine – 92.3% 2E Recovery East Boulder Mine – 91.0% Pd:Pt Ratio Stillwater Mine – 3.51:1 Pd:Pt Ratio East Boulder Mine – 3.60:1 105 Risk Assessments The Qualified Person has completed a high-level semi-quantitative risk analysis of the Sibanye-Stillwater US PGM Operations discussed in this Technical Report Summary. The risk analysis sought to establish how the Mineral Reserve estimates for Stillwater and East Boulder Mines could be materially affected by risk factors associated with or changes to any aspect of the modifying factors. For the high-level risk analysis, the Qualified Person has assessed a material risk identified as an issue for which there is a substantial likelihood that a reasonable investor would attach importance in determining whether to buy or sell the securities registered for Sibanye-Stillwater. A material risk should also have a high chance (likelihood) of occurrence. If an issue does not satisfy both criteria, it has been identified as a low to medium risk depending on its impact if it occurs and the likelihood of occurrence. Sibanye-Stillwater has a risk management process in place at the Sibanye-Stillwater US PGM Operations that identifies risks, assesses the materiality of the risks, and provides risk mitigation measures where possible. The Qualified Person could not identify any material risk to the Mineral Reserves associated with the modifying factors or resulting from changes to any aspect of the modifying factors. However, the Qualified Person provides the following opinions relating to the low to medium risks identified in the modifying factors and the mitigation measures in place to minimise the impact of the risks: • Geotechnical: Stillwater and East Boulder Mines have accumulated an extensive geotechnical database and developed ground classification (ground control districts) and support measures that are suited to the rockmass conditions for each of the ground control districts. These measures have significantly reduced major falls of ground at Stillwater and East Boulder Mines. However, there is always a degree of residual low risk relating to excavation failures. The extensive support systems and standards in place at both mines are sufficient to minimise the potential impact of any geotechnical associated risk. • Geohydrological: Mining operations at Stillwater and East Boulder Mines have not experienced material interruptions due to groundwater problems, with both mines being relatively dry in the upper sections. However, a significant amount of groundwater was encountered at the Stillwater East Section during the development of the main access adits and the decline, but conditions have improved significantly with further development. Despite the declining groundwater inflow, the groundwater poses a low risk in terms of excavation stability and the management and disposal of the water generated. Stillwater Mine has already initiated a multi-pronged approach to mitigating this risk which involve the following: o The drilling of probe holes well in advance of any advancing development end; o Carrying out hydraulic tests of probe holes drilled prior to drift advancement whenever practically possible; o Cementation (grouting) ahead of those advancing development ends where the potential for significant water intersections have been identified; o Probe and definition drilling before developing new production areas to evaluate water inflows, with some of these drillholes converted into drain holes for dewatering purposes; and o Evaluating, engineering, and permitting expanded water handling and disposal facilities on surface to manage excess mine water. • Inability to execute LoM plans: Although mining experience at the Stillwater and East Boulder Mines has provided improved understanding of the mineralisation, modelling ability and understanding of the modifying factors, estimation errors cannot be eliminated. The major expected sources of error in the Mineral Reserve estimates include understating production costs, slower than planned production build-ups, understating manpower requirements, regulatory 106 changes, grade and tonnage underestimation and unknown geological conditions. These factors are partially mitigated by using a significant amount of historical data in the LoM forecasting of key elements of the operations, namely RoM ore production levels, RoM ore grades and operating costs. Furthermore, the mines have systems and personnel in place that monitor the mining operations daily (short interval control) to enable the implementation of timeous interventions and, therefore, correction of deviations to the plans. • Unplanned production cost escalation: In recent years since 2019 until 2021, there has not been significant escalation of the production costs. The production costs were mainly affected by the quantities of ore and waste produced each year from each mine and the mining methods employed, with the cost-effective Ramp and Fill methods utilised for most stopes at both mines. Continuous improvement initiatives adopted to contain cost escalation included the increasing use of mechanised mining methods thereby improving productivities and reducing operating costs, the optimisation of the mining fleets (reducing active units) to reduce maintenance costs and increase mining volumes through mining footprint expansion at Stillwater Mine (Stillwater East Section) and optimal utilisation of available hoisting and milling capacities at East Boulder (Fill The Mill Project). Since 2020 and coinciding with the COVID-19 pandemic, the operations have experienced significant cost pressures due to external and internal factors which were compounded by production disruptions caused by the COVID-19 pandemic. The further impact of this risk has been accounted for in the budgeting by allowing for significantly higher cost escalation than historically experienced. • Power losses: The loss of power at the mining operations during the winter months (due to excessive snow and high winds) is the single low to medium risk identified relating to mining infrastructure. The power losses are infrequent and are mitigated by using backup generators. The generators have sufficient capacity to power surface and underground fans to ensure that personnel can be safely withdrawn from the underground mining operations, if required. • Inadequate tailings storage capacity: Tailings storage facilities at Stillwater and East Boulder Mines have adequate storage capacity for the medium term (seven to ten-year range). Production increases at both mines have shortened the lives of the tailings storage capacities. Tailings storage capacity upgrade through elevation lift is a mitigation measure that has been adopted while permitting for the construction of new tailings facilities is being pursued. Permitting for the construction of a new tailings storage facility may require periods of three to five years. Sibanye- Stillwater is aware of the long approval timeframes and has already completed the necessary technical studies and submitted the required permit applications to initiate the permitting processes. It is unlikely that the operations will run out of tailings storage facility capacity before Sibanye-Stillwater receives approvals for the construction of new tailings storage facilities or the upgrading of the existing tailings storage facilities. • Metal price downturns: The prices for palladium and platinum fluctuate depending on global supply and demand. Demand for palladium and platinum primarily depend on their use in auto- catalytic converters for both gasoline and diesel engines. Sensitivity analysis of the NPV for the Sibanye-Stillwater US PGM Operations for variation in metal prices indicates robust economics due to the high-grade nature of the J-M Reef and that significant revisions of the Mineral Reserves for Stillwater and East Boulder Mines would only result from a significant metal price decrease. The estimated revenue per combined ounce of palladium and platinum over the LoM plans varies depending on which parts of each of the mines are being exploited. This offers the mines the flexibility to delay the mining of sub-economic areas during times of price downturns. 107 MINING METHODS Introduction Stillwater and East Boulder Mines are mature operations extracting the J-M Reef using well-established mining methods. Most of the permanent infrastructure required to access the underground operations is already established and being upgraded where necessary to accommodate production increases anticipated in the LoM plans for the operations. The LoM plans for Stillwater and East Boulder Mines, which underlie the Mineral Reserves, were constructed internally by Sibanye-Stillwater’s Qualified Person supported by Technical Experts and utilising modifying factors and capital and operating costs which are informed by historical experience at the mines. Accordingly, the technical inputs, modifying factors, staffing levels, capital and operating costs utilised for LoM production planning and conversion of Measured Mineral Resources to Proved Mineral Reserves are within ±15% accuracy and the costs allow for up to 10% contingency. However, for the LoM production planning and conversion of Indicated Mineral Resources to Probable Mineral Reserves, the inputs and costs are within ±25% accuracy and the costs allow for up to 15% contingency. The economic viability of the LoM plans was assessed through detailed cash flow analysis. Mine Design Mining Method Rationale The J-M Reef outcrops over a 28-mile strike length on the Sibanye-Stillwater Mining Claims but the topography, altitude and thickness of the reef preclude economic exploitation of the reef through open pit mining methods. Accordingly, waste stripping which would be applicable to an open pit mining is not required. At Stillwater Mine, the dip of the J-M Reef varies from 40° to 90° to the north, with an average of 60°. Reef thickness varies from 3ft to more than 9ft but averages 6ft. The J-M Reef at East Boulder Mine dips 35° to 55° (averaging 50°) to the north. The shallowest dip (35°) is observed in the far west area accessed by the 6500 Level Footwall Lateral. Both Stillwater and East Boulder Mines employ the following underground mining methods, which are suited for the variable steep dips and narrow widths of the J-M Reef: • Captive Cut and Fill stoping, utilising either conventional, AlimakTM or raise boring to create accesses, and the resulting stopes are also known as captive stopes – this method is being phased out; • Ramp and Fill using overhand or underhand approaches; and • Sub-level extraction by long hole open stoping with subsequent backfill. Longitudinal and transverse stoping methods are variations of the long hole stoping method in use at the mines. The mining method mix is adjustable and largely driven by mineralisation grade, ground conditions encountered and the requirement to minimise dilution. The percentage distribution (frequency of use) of the three mining methods within each of the mines since FY2016 is shown in Table 22 indicating the predominance of the mechanised Ramp and Fill method. Ramp and Fill stoping (which includes on-reef sub-level sill development) is the predominant mining method at both mine-sites. The Ramp and Fill method allows for maximum selectivity for separating ore and waste. Sub-level extraction long hole
108 stoping is utilised typically in narrow continuous ore zones. Captive Cut and Fill stoping is only used on rare occasions when the other two methods are not practical ceased in 2021. Except for open stoping, the mining methods employ high-quality sand or paste as backfill, with limited use of Cemented Rock Fill (CRF) and/or other backfill materials. Table 22: Mining method frequency of use at Stillwater and East Boulder Mines Mining Method Frequency of Use Stillwater Mine East Boulder Mine Captive Cut and Fill 1% 0% Mechanised Ramp and Fill 85% 79% Sub-level Extraction Long Hole Open Stoping 14% 21% Ramp and Fill Method Overhand Ramp and Fill stoping is the predominant mining method at the Stillwater and East Boulder Mines while 11% to 20% of the stopes at the Stillwater Mine are extracted through undercut Ramp and Fill stoping. The two Ramp and Fill applications practiced at the mines are illustrated in Figure 43. The backfill for the overhand and underhand Ramp and Fill stoping are predominately sand (classified to coarse fraction mill tailings) and paste, respectively; however, CRF is also utilised in limited applications at the Stillwater Mine. Where ground conditions permit, the overhand method is preferred as it is more cost effective. Where less stable ground conditions dictate, underhand Ramp and Fill is applied, with the more expensive paste backfill also used. Up to 12% cement is used in the paste fill, as needed, to provide a stable overhead cemented paste material. Furthermore, development ramp gradients should not exceed 18%. Breast holes are drilled on most of the Ramp and Fill stopes areas using single-boom drill jumbos and, after blasting, the broken rock material is loaded by 2.5 cubic-yard LHDs. Figure 43: Overhand and Underhand Ramp and Fill Mining Methods 109 Captive Cut and Fill Method Several variations of the Cut and Fill method have been practiced at Stillwater Mine, but this method is now employed to mine isolated remnant Mineral Reserve blocks, representing 1% of the total stope volumes mined in FY2021. These blocks are either accessed using AlimakTM raise climbers or equipped raise bore holes. Sandfill (coarse fraction tailings material) is used for the backfill. All the Stillwater Mine’s Captive Cut and Fill stopes use hand-held jackleg drills for drilling and electric slushers for moving the broken ore from the headings to the ore passes. This equipment remains in the captive stope as it advances upward. The Captive Cut and Fill method has been phased out in due to safety considerations. Sub-level Extraction and Sub-level Development Where the J-M Reef and hangingwall are competent and the reef has good continuity, sub-level longitudinal open stoping using relatively shorter “long holes” compared to those in other mining districts is applied. This extraction method is illustrated in Figure 44. The sub-levels are driven on the reef plane at 20ft to 50ft intervals. Considerable tonnage generated by driving sub-levels in the reef is accounted for as Sub-level Development tonnage; this is accounted for in the “Mechanised Cut and Fill” percentage. Figure 44: Sub-level Extraction (Longitudinal) Long Hole Open Stoping In the Sub-level Extraction Longitudinal stoping method, sub-level sills are driven with narrow single-boom jumbos. The long holes are drilled by long hole pneumatic and electric hydraulic drill rigs. Once the sub- levels are advanced, a drop raise is drilled from the upper sub-level to the lower sub-level and blasted at the end of the stope over the full width of the reef at that point. Blast holes are then drilled downward on a pattern between the sub-levels and blasted towards the open cavity of a slot raise. Support pillars are left in place on approximately 80ft to 100ft intervals on the reef in the stope to minimise hangingwall 110 failure and ore dilution. The broken ore is mucked from the sub-level below using remote-controlled, diesel-powered LHDs and then trammed to the nearest ore pass. Transverse Long Hole Stoping Where the J-M Reef and rock mass quality of the hangingwall limit the length of open longitudinal mining span but the reef has good continuity, Transverse Long Hole stoping is applied using relatively shorter “long holes” compared to those in other mining districts mined through Longitudinal Long Hole stoping. This extraction method is illustrated in Figure 45. Figure 45: Transverse Long Hole Open Stoping The secondary footwall lateral drives are driven parallel to the reef at 30ft to 50ft intervals and approximately 30ft from the closest ore zone to allow for adequate distance to safely remote-muck panels that are mined between the secondary footwall lateral drives. Approximately 20ft wide primary and secondary slots are driven from the secondary footwall lateral drives into the reef. Considerable tonnage generated by drilling panels between the slots in the reef is accounted for as Sub-level Development tonnage. The panels are backfilled with cemented rock fill in the primary panels whereas gob or sand is used to backfill the secondary panels. Panels alternate following the cemented rock fill – gob - cemented rock fill pattern, and those that are gobbed must have either rock or cemented rock fill on both sides. The secondary footwall lateral drives are driven with two boom or single boom jumbos whereas the slots are driven with narrow single-boom jumbos. The long holes are drilled by pneumatic or electric/hydraulic 111 longhole drills. Once the slots are advanced, a drop raise is drilled from the upper slot-level to the lower slot-level along with additional drillholes for the desired length of the slot; this is referred to as the panel. The drop raise and panel blast holes are shot together at the end of the stope over the full width of the reef slot at that point. Blast holes are drilled downward on a pattern between the slot-levels and blasted towards the open cavity of the secondary footwall lateral drive. The broken ore is mucked from the secondary footwall lateral drive level below using remote-controlled, diesel-powered LHDs and then trammed to the nearest ore pass. Stope Extraction Ratios The regional and local extraction ratios computed from actual data for Stillwater and East Boulder Mines are shown in Table 23. The Qualified Person notes that the regional extraction ratios in Table 23 are low as large areas of the reef were previously left unmined due to the use of high cut-off grades when palladium prices were low. Extraction ratios are set to increase as 2E cut-off grades have been lowered to 0.20opt and 0.05opt at Stillwater and East Boulder Mines, respectively, in response to significant continuous increases in the palladium price since 2017. Table 23: Stope Extraction Ratios Scale Mining Method Extraction Ratio (%) Stillwater Mine East Boulder Mine West Section East Section All Sections Local (Stope) Captive Cut and Fill 85 90 NA Mechanised Ramp and Fill 90 90 95 Long Hole Open Stopes 60 60 60 Regional (Mine) Overall 40 40 50 Hydrogeological Model Stillwater Mine Based on the hydrogeological model discussed in Section 9.9.1, no known major changes in groundwater conditions are expected in the Stillwater West Section, with this section expected to remain dry on average. Currently, the mine is evaluating what to expect west of the Edge of the World Fault through a hydrogeological study. The mine is currently evaluating, engineering and permitting to handle these increased flows which may be in the order of 1 600gal per minute estimate from a 2017 Itasca study. Stillwater Mine has introduced the following operational interventions to assist with the management of groundwater intersections in underground excavations: • Drilling of probe holes well in advance of any advancing development end; • Carrying out hydraulic tests of probe holes drilled prior to drift advancement whenever practically possible; • Full cover grouting ahead of development that has the potential to intersect significant quantities of groundwater; • Carrying out additional monitoring/testing as warranted if the identified basins exhibit notably different groundwater conditions;
112 • Evaluating groundwater inflows from definition drillholes before developing new production areas and, where appropriate, converting these drillholes into drain holes for depressurisation/dewatering purposes; and • Manifolding drain holes together, wherever possible, to collect the discharge water into a smaller number of flow points that can then be monitored and directed to pumping facilities and setting up all drain holes to record the line pressures and discharges (cumulative volumes rather than instantaneous rates) from separate/individual areas. The Qualified Person is satisfied that most of the potential sources of groundwater have been identified and accounted for in the mine design while appropriate operational interventions have been proposed for the management of groundwater at Stillwater Mine. The designs prescribe direction for development or the placement of crown and rib pillars to protect the underground excavations from uncontrolled water in rushes. The Qualified Person also notes the importance of continuous monitoring using probe drillholes to facilitate early detection of any potential unidentified water sources. East Boulder Mine Mining at East Boulder Mine is planned in areas situated adjacent to active mining fronts that have not experienced any groundwater issues as the host rock has low permeability. Furthermore, these areas are located at a higher elevation than the lowest level of the mine (the 6500 Level) which currently acts as a drawdown point for surrounding groundwater levels. Inflows are likely to be similar or lower than those experienced by historical mining operations, with the average mine-wide water inflow only likely to increase slightly with the increase in development and production activity associated with the Fill the Mill Project. One fault system encountered at the 71300 area that bears water and has been slowing development efforts has been accounted for in the mine plan. Significant water will also likely be encountered in other significantly faulted and jointed areas or when encountering alluvial systems associated with surface channels as mining gets within 500ft of surface. The Qualified Person is satisfied that the mine designs for East Boulder Mine prescribe direction for development or the placement of crown and rib pillars to protect the underground excavations from uncontrolled water in rushes. Furthermore, the standard practice at East Boulder Mine of drilling water probe holes prior to any development work to mitigate the risk of encountering water has been adequate in detecting groundwater inflows while diamond drilling on 50ft centres results in a good understanding of water potential before mining activity begins. Geotechnical Model Geotechnical Characterisation The J-M Reef and its immediate hangingwall and footwall consist of varying assemblages of norite, anorthosite, leucotroctolite and peridotite. As the lithological sequence is similar at Stillwater and East Boulder Mines, a universal approach is adopted for support designs at both mines. The rock units contained within the J-M Reef, Footwall and Hangingwall Zones are classified as strong based on UCS ranging from 60Mpa to 85Mpa. Mining and support designs are adjusted accordingly when lower strengths are commonly associated with olivine cumulates or geological structures are identified in the 113 drillcores. The Q-values obtained for Stillwater and East Boulder Mines ranging from 1 to 13 indicate poor to good rock mass conditions, where the area split for fair, good and poor conditions is 50%, 25% and 25%, respectively. Support Design The ground support requirements for the primary development are described in the standard operating procedures, which detail the requirements for the three ground types (Type I, II, and III). Ground conditions that are assessed by Miners or Supervisors to be poorer than Type III ground will be re-assessed by the Geotechnical Engineer as the many variables causing poor ground mean that it is unlikely that a standard approach can be applied. The Geotechnical Engineer will recommend appropriate support for such areas. Support designs for the Benbow Decline which was completed in Q4 of FY2021 in the Stillwater East Section has incorporated primary development support designs employed at the Stillwater West Section and East Boulder Mine. Rock mass characteristics determined for the assessment of geotechnical data is used to delineate geotechnical domains of similar characteristics. The ground type domains and applicable ground support requirements are integrated with other design and planning information. Areas prone to anomalous rock-related risks are then identified for every planned stope within a “Stope Proposal” document. Ground support employed on the reef is typically pattern-bolting with mesh, which is a combination of friction stabilisers and resin anchor rebar bolts. Due to the requirements to maintain the minimum mining width, it is not possible to drill and install rockbolts in the typical stope envelope with the commercially available mechanised bolters. For this reason, bolts are installed with either jacklegs or CMAC support drill rigs. Support rib pillars are left in place as the stope retreats along strike to keep the hangingwall stable in areas mined through the Sub-level Extraction Long Hole stoping method. In general, low-grade areas of the reef excluded from mining provide additional regional pillar support. Mine personnel are appropriately trained to perform routine basic checks on ground support or changes in ground conditions as part of their daily inspection of the work areas. Internal and external Geotechnical Engineers are then requested to assess geotechnically complex areas. Stillwater and East Boulder Mines routinely engage the services of external consultants to provide geotechnical oversight functions related to ground support performance, stope performance and design at least once every year. Both mines currently use a Trigger Action Response Plan (TARP) in regard to ground conditions and ground support. With progression from a TARP 1 to TARP 3, the plan is escalated to higher levels within the organisation for review. The Qualified Person is of the opinion that support designs for primary development and stopes utilised at Stillwater and East Boulder Mines for decades are appropriate for the ambient rock mass conditions encountered and mining methods used at both mines. A wealth of geotechnical data exists for the mines upon which appropriate stope sizes and support practices have been designed through detailed engineering. These support designs and operational practices have also been accounted for in the overall mine designs for the Stillwater East section of Stillwater Mine. 114 Surface and Subsidence Control Regulatory permits have been issued to Stillwater and East Boulder Mines by the Department of State Lands, State of Montana regarding the minimum size of crown pillar to be left from surface and the shallowest depth of stoping activities. These permits specify a 20ft to 50ft crown pillar of competent bedrock for mining below surface terrain that does not contain water courses otherwise a 200ft crown pillar of competent bedrock should be used. The Qualified Person has confirmed that appropriately sized crown pillars have been incorporated in the mine designs for Stillwater and East Boulder Mines. Backfill 15.4.4.1 Overview Hydraulic sandfill comprising a coarse fraction of the tailings is the backfill used in most stopes mined through the Ramp and Fill method. However, cemented tailings paste is used in stopes mined through the Cut and Fill method to provide sufficient backfill strengths to support when the underhand mining approach is employed. The use of tailings as backfill is also important for tailings volume reduction, with approximately 53% to 60% of the tailings material generated at Stillwater Mine and 48% of tailings generated at East Boulder Mine used as backfill. No additional steps are necessary to treat any tailings placed back into the mine. CRF is employed on the Stillwater East Mine and is a combination of run of mine waste rock and cement. Some air entrained cementitious products (e.g., TekSeal) are being tested and utilised in the Stillwater East Section until such time that a paste product is available for use in this section. 15.4.4.2 Stillwater Mine For the Stillwater West Section, tailings from the Stillwater Concentrator scavenger circuit are pumped to the sandfill plants, where up to 60% is used in the mine backfill process (via the use of cyclones for segregation of -45µm material). A paste fill plant is situated on surface close to the portal from where paste is pumped into the mine via the 5150W from where it is then distributed to the workings requiring fill. The section also has three sandfill plants, with two (i.e., the 4900 Level and 5000 Level Sandfill Plants) situated close to the portal area and the third situated on the 5500W Level providing sandfill for the Upper West mining area. The supply of tailings to the 5500W Level Upper Sandfill Plant is passed through a booster pump in the 5500 Level Portal and cyclones to remove the fine fraction (-45µm) after which the coarse fraction is placed in storage silos. Sandfill is dispatched to the stopes requiring fill mainly by gravity to the Off Shaft mining area and by high pressure positive displacement pumps for the workings above the 5000 Level; it should be noted that many levels can be serviced from more than one plant- either gravity fill from the 5500 Plant or high-pressure pump from the 5000 Plant. There is also a booster pump station on the 6300 Level for workings above the 6300 Level. The fines fraction of the tailings is returned to surface via centrifugal pumps for storage at the TSF. To support the overhand Ramp and Fill mining in the Stillwater East Section, hydraulic sand backfill is delivered from the Stillwater West Section. This arrangement is made possible by the fact that the initial 115 production areas in the Stillwater East Section are within the delivery envelope of the displacement pump located at the 5000W Level Sand Plant. A sandfill plant situated at 5400E-10400 has been established to meet the backfill requirements when the production areas expand beyond the delivery envelop of the 5000W Level Sand Plant. A 4-inch sand delivery pipe installed from the 5000W pump to the Stillwater East Section serves as the main feed to the 5400E-10400 Sandfill Plant. CRF is utilised in the Stillwater East Section as it exceeds the envelope from the 5150 Level paste plant. A plant from the 55E decline at E10300 creates CRF from mine waste (that is crushed at an adjacent crusher plant) and cement (constituting approximately 8%). The product is delivered with underground ejector trucks to stopes and then jammed/placed with a 4 cubic yard LHD. CRF represents only 4% of placed backfill product at the Stillwater mine. The Qualified Person note that Sibanye-Stillwater is currently engaged in an engineering study to deliver thickened tails to the Stillwater East Section for the production of paste for use in underhand ramp and fill stoping blocks. They anticipated that a paste plant can be fast-tracked and in use by FY2024. 15.4.4.3 East Boulder Mine Stopes at East Boulder Mine are backfilled with un-cemented hydraulic sandfill delivered from the East Boulder Concentrator on surface to an underground sand plant located on the 6500 Level from where the sandfill is distributed by booster pumps to two other sandfill plants on the 7200 Level and 8200 Level. Similar to Stillwater Mine, the tailings material is pumped through cyclones to remove the fine fraction and the coarse fraction is placed in six underground storage silos while the fine fraction is returned to surface via centrifugal pumps for storage at the tailing storage facility (TSF). Sandfill is dispatched to the stopes requiring fill by positive displacement pumps. All decant and flush water reports into the mine wastewater system, which reports to the main pump station on the 6450 Level. Stillwater Mine Operations Background Established in 1986, Stillwater Mine has produced approximately 60 000 tons of RoM ore per month from a single section – the Stillwater West Section – with the RoM ore processed at the onsite concentrator. A step change in production output to approximately 106 000 ton per month necessitated mine expansion into the Blitz area – the Stillwater East Section. Development of the Stillwater East Section (i.e., the Blitz Project) commenced in 2011 with the excavation of access adits and this has been ongoing to date. Development of the capital infrastructure (access drifts, decline and ramps, and ventilation shafts) required in the Stillwater East Section is currently at an advanced stage and expected to be finalised during FY2024. Ore production from the Stillwater East Section commenced in late FY2017 and has gradually been ramping up towards a steady state monthly production level of approximately 43 000 tons by FY2025.
116 Key Operational Infrastructure Stillwater Mine includes the mining operations and ancillary buildings that contain the concentrator, workshop and warehouse, changing facilities, headframe, hoist house, paste plant, water treatment, storage facilities and offices. All surface infrastructure and TSFs are located within the Stillwater Mine Operating Permit, which covers an area measuring 2 450 acres. Stillwater Mine has developed an approximately 9-mile-long segment of the J-M Reef encompassing the Stillwater West and East Sections in the eastern part of the Stillwater Complex. Mine Layout The underground mine layout for Stillwater Mine is illustrated in Figure 46. The Stillwater West Section has been divided into three large mining areas, namely the Off-shaft, Upper West and Lower West areas, using geological domain boundaries. These domains have been subdivided into mining blocks as follows (Figure 9): • Block 1 and Block 2 in the Upper West area, which is above the 5000 Level in the Dow Sector; • Blocks 1 and 2 in the Lower West area, which is below the 5000 Level in the Dow Sector; • Blocks 3 and 6 in the Off Shaft West area; and • Blocks 7 and 8 in the Off Shaft East area. The Stillwater East Section has been divided into two large mining areas, namely Blitz West and Blitz. 15.5.3.1 Stillwater West Section Access to the reef in the Stillwater West Section is by means of a 2 000ft Vertical Shaft and a system of horizontal adits and drifts driven parallel to the strike of the J-M Reef at vertical intervals of between 150ft and 400ft. Ten main adits have been driven from surface portals on the west and east slopes of the Stillwater Valley at various elevations between 5 000ft and 5 900ftamsl. Five principal levels have been developed below the valley floor by ramping down from the 5 000ft level to extract ore from the J-M Reef down to the 3 800ftamsl elevation. Four additional major levels below the 5 000ft level are accessed principally from the vertical shaft and shaft ramp system. The mine has developed a decline system from the 3 200ft elevation to access and develop deeper areas in the central part of the mine below those currently serviced by the existing shaft. The decline system currently accesses the 2900, 2600, 2300, 2000, 1700 and 1600 Levels. It was the objective to keep these footwall developments approximately 100ft to 150ft from the J-M Reef, so that a fan of diamond drillholes could be drilled across the J-M Reef at 50ft intervals. The footwall laterals were originally driven on 200ft vertical intervals, but this spacing was increased to 300ft. The Vertical Shaft system provides access to the workings below 5000W Level. It serves as a conduit for the transport of men and materials while also hoisting broken rock (ore and waste) to surface. The Stillwater West Section currently uses its 300ft spaced laterals, six primary ramps and vertical excavations to provide personnel and equipment access, supply haulage and drainage, intake and exhaust ventilation systems, muck haulage, backfill plant access, powder storage and/or emergency egress. The footwall lateral and primary ramp systems will continue to provide support to production 117 and ongoing development activities. In addition, certain mine levels are required as an integral component of the ventilation system and serve as required intake and or exhaust levels, or as parallel splits to maintain electrical ventilation horsepower balance and to meet the Mine Safety and Health Administration (MSHA) Regulations. MSHA Regulations also contain requirements for alternate (secondary) escape-ways from mine workings and these levels also meet this need. These levels serve as permanent mine service-ways and are used for road and rail transportation, dewatering and backfill pumping facilities. 15.5.3.2 Stillwater East Section The Stillwater East Section is currently under development, with footwall lateral level spacing of 400ft being used. The 5000E Footwall Drive serves as the main access to this section. This drive has also been equipped with rails and serves as the main gathering haulage where ore and waste are transported out of the mine using trains. The development of the 5600E Footwall Drive, which is positioned 600ft above the 5000E Footwall Drive, is currently ongoing. This drive will provide access to the stoping blocks. In the eastern part of the Stillwater East Section, the Benbow Decline intersected the 5600E Footwall Drive for the provision of additional egress access and as a ventilation intake. The holing with the 5600E Level from the western portion of the Stillwater East Section is anticipated in Q4 FY2022. East Boulder Mine Operations Background East Boulder Mine was established in 1997 and started producing ore in 2002 at approximately 55 000 tons per month. It is currently operating at the steady state monthly RoM ore production level of approximately 65 000 tons per month after ramping up production in line with the Fill the Mill Project implemented to utilise the historically unused capacity of the East Boulder Concentrator. At the current steady state, mining output will be maintained at approximately 785 000 tons per annum. During FY2020, several key elements required to increase production levels and take advantage of the unused mill capacity were put in place. The 72740-production ramp system was developed, and production mining was initiated. An incline was developed to meet the existing Frog Pond Adit which serves as both a ventilation path to surface as well as a secondary egress with a surface shelter. In Q3 FY2020, the Fill the Mill project was completed, and production increased in FY2021 reaching the revised steady state level. Key Operational Infrastructure East Boulder Mine includes the underground mining operations and surface support facilities such as the concentrator, workshop and warehouse, changing facilities, water treatment, storage facilities, office and TSF. All surface infrastructure and the TSF are located within the East Boulder Mine Operating Permit, which covers an area measuring 1 000 acres. East Boulder Mine has developed an approximately 5- mile-long segment of the J-M Reef encompassing the Frog Pond East and West Sections in the western part of the Stillwater Complex. 118 Mine Layout The underground mine layout for East Boulder Mine is illustrated in Figure 46. The predominant mining method is Overhand Ramp and Fill method complemented by limited Sub-level Extraction Long Hole stoping. The J-M Reef at East Boulder Mine is accessed by two access drives, each 3.5 miles long and 15ft in diameter, developed perpendicular to reef strike to intersect the J-M Reef from the north. The access tunnels from surface intersect the reef at an elevation of 6 450ftamsl. Footwall haulages have been developed east and west from this intersection point to open the strike extent of the deposit. The stopes are accessed up-dip by ramps and footwall lateral drifts on 200ft to 400ft vertically spaced levels located approximately 150ft to 200ft from the J-M Reef. Measured Mineral Resources converted to Proved Mineral Reserves are delineated by definition diamond core drilling from these headings, which are also used for stope access and development. The current mine occupies a 5-mile-long footprint which is 2 300ft in vertical extent. The mine plan anticipates the 9400 Level to be the ultimate upper level in the mine. The main adit haulage level is the 6500 Level with the 670 Ramp system having been developed to the 9100 Level. Except for the adit rail haulage, the mine is operated as a trackless mining operation. The 6500 Level footwall haulage extends laterally for a nominal 21 000ft, and the 6700 Level footwall haulage extends laterally for a nominal 18 000ft. The levels are connected by spiral ramps and the reef is accessed by cross cuts. Between 2010 and 2015, the west end of the 6500 Level was extended further west to the Graham Creek area to connect to the Graham Creek vertical raise. 119 Figure 46: Generalized Underground Layouts for Stillwater and East Boulder Mines
120 Life of Mine Planning and Budgeting Introduction The Mineral Reserves for Stillwater and East Boulder Mines are reported from LoM production schedules, which have been tested for economic viability. Stillwater Mine will produce ore from the mature Stillwater West Section and the Stillwater East Section under development. Stillwater Mine is forecast to attain steady state production by FY2027. East Boulder Mine will produce ore concurrently from the mature higher-grade Frog Pond West Section and lower-grade Frog Pond East Section. East Boulder Mine is forecast to operate at the steady state production level from FY2022 until the end of FY2049, thereafter reducing for the remainder of the LoM (FY2061). Stillwater and East Boulder Mines utilise the DeswikTM suite of mine design and scheduling software. Both mines use a common approach to LoM planning whereby each identified stoping block is scheduled in terms of forecast ore tonnage, waste tonnage and head grade for the LoM plan. In addition, the scheduling process accounts for the following: • Mineral Resource tons and grades; • Dilution; • Stoping tons generated per Miner per month; • In-stope development rates and ore generated per month; • Primary development rates and waste generated per month; and • Secondary development rates and waste generated per month. Different approaches were followed for the scheduling of Indicated and Measured Mineral Resources to derive the LoM production schedules for each mine. The differences in approach were necessitated by the differences in geological confidence for Indicated and Measured Mineral Resources. For the conversion of Measured Mineral Resources to Proved Mineral Reserves, the high abundance of geological information available to accurately constrain thickness, tonnage and grades and the accuracy of technical and cost inputs permit the compilation of estimates to a level of accuracy of within ±15% (Feasibility Study level of accuracy). For the conversion of Indicated Mineral Resources to Probable Mineral Reserves, the sparse geological information limits the confidence in the estimates. As a result, the conversion relies on statistics on key metrics extrapolated from the Proved Mineral Reserve areas per domain and mining block. The Mineral Reserves in these Indicated Mineral Resource areas are defined to a lessor level of accuracy of ±25% (Preliminary Feasibility Study level accuracy). Mine Planning Criteria The Stillwater West Section carries out approximately 20 000ft of primary development per annum while the Stillwater East Section is currently developing 15 000ft annually as it expands to the east. Currently, the mining footprint at Stillwater Mine spans approximately 45 000ft of strike length. LoM planning and scheduling criteria for stoping and development are summarised in Table 24 and Table 25. East Boulder Mine conducts approximately 18 000ft of primary development per annum to expand the mining and Mineral Reserve footprints. LoM planning and scheduling criteria for stoping and development are summarised in Table 26 and Table 27. All data utilised in the development of the LoM schedule is based on historical data gathered since the inception of the mines. 121 Table 24: Planning Parameters for Stoping for Stillwater Mine Mining Method Stoping Parameters Total Tons Per Miner Per Month Percentage Ore Mining Mix Captive Cut and Fill 205 90% 0% Ramp and Fill 450 70%* 93% Sub-level Extraction 315 100% 7% Pillar Extraction 315 100% 0% * 100% Probable Mineral Reserves Table 25: Planning Parameters for Primary Development for Stillwater Mine Area Primary Development Parameters Advance Factor Number of Crews Advance Feet Per Month Tons Per Foot Off-shaft 0.96 1 60 13 Off-shaft East 0.96 1 60 13 Lower Far West 0.90 1 60 13 Far West 0.90 1 60 13 Depression Zone 0.90 1 60 13 Stillwater East 0.96 5 60 20 Table 26: Planning Parameters for Stoping for East Boulder Mine Mining Method Stoping Parameters Total Tons Per Miner Per Month Percentage Ore Mining Mix Captive Cut and Fill 236 100% 0% Ramp and Fill 567 90% 80% Sub-level Extraction 708 100% 20% Sub-level Development 567 85% 0% Pillar Extraction NA NA NA * 100% Probable Mineral Reserves Table 27: Planning Parameters for Primary Development for East Boulder Mine Area Primary Development Parameters Advance Factor Number of Crews Advance Feet Per Month Tons Per Foot Frog Pond West 0.95 1 60 14 Frog Pond East 0.95 1 60 14 Lower Frog Pond East 0.90 1 60 14 Lower Frog Pond West 0.90 1 60 14 Historical analysis of mine planning and production data revealed that a recovery factor was required to reconcile blasted and removed tons in the sub-level extraction stopes in the Upper West area of the mine. The historical production data indicated that 25% of the broken material was not recovered from these mining areas. Both the HoverMap and LIDAR scan data of more than 100 stopes have also confirmed this under recovery. Therefore, a 75% recovery factor was applied to all sub-level extraction tons and ounces since December 2005. The technical teams remained focused on reducing these lost tons through modifying blasting practices. The unit dimensions for each stope block varies depending on lateral spacing (300ft to 400ft), reef width, economic (pay) strike length, rib and sill pillar requirements. The stope unit dimension is finalised during the mine design and scheduling process. The typical Ramp and Fill stope design illustrated in Figure 47 indicates that the total height is 300ft, inclusive of sill pillars, with an overall extraction length of 2 000ft and at a minimum mining width of 8.5ft. 122 Figure 47: Typical Ramp and Fill Stope Design Modifying Factors 15.7.3.1 Introduction The technical (mining and survey) modifying factors employed in the conversion of Mineral Resources to Mineral Reserves through a LoM design and scheduling process are reviewed annually and adjusted appropriately by the Qualified Persons based on historical mine production reconciliation and tons and grade delivered to mill. Stillwater and East Boulder Mines have completed reconciliation studies to attempt to more accurately quantify the modifying factors employed for the conversion of Mineral Resources to Mineral Reserves, namely dilution, Mine Call Factor and deletion, and to more accurately report the expected tons and head grade delivered to the concentrator. The Qualified Person approved the modifying factors employed for the development of the LoM plans for Stillwater and East Boulder Mines. 15.7.3.2 Mining Dilution Dilution factors applied for the conversion of Mineral Resources to Mineral Reserves are based on historical reconciliation for each mining method and results of the recent studies reviewing the modifying factors. Based on historical data, a dilution factor has been introduced which is the amount of material added to the ore at zero grade during stoping operations. For example, 13% more tons than planned in the case of Dow UG Upper are added to the ore tons delivered to the concentrator at an assumed 2E grade of 0opt. The result is that 13% more ore tons are delivered to the concentrator but at a lower head grade. Table 28 summarises the dilution factors and methodology utilised in the Mineral Resource to Mineral Reserve conversion for the various mining methods in each of the sub-areas at Stillwater Mine. While Mineral Resources are reported at a single minimum mining width (MMW) of 7.5ft given the predominance of the Ramp and Fill method at Stillwater and East Boulder Mines, a different approach to the application of the minimum mining width was followed for mine planning. Instead of using the diluted block model employed for Mineral Resource estimation, which assumes 100% mining via the Ramp and Fill method, the original undiluted (channel) block model for the reef channel was used. To 123 the channel block model, minimum mining widths adjustments based on the mining method per reef domain were applied in the Proved Mineral Reserve areas. The minimum mining widths set a standard for the best-case recovery of a Mineral Reserve for a given mining method and stope location, which can be used to measure mining performance. An extra 1.5ft hangingwall and footwall dilution is added to the ore width for areas mined using the 2.0-cubic yard LHDs but an extra 1.0ft of dilution was added for all other mining methods. In addition, if the ore width plus the extra dilution is less than or equal to the applicable minimum mining width, then the diluted width would be equal to the minimum mining width, but if the ore width plus the extra dilution is greater than the minimum mining width then the diluted width would be adopted. Since 2020, additional dilution has been added to the Mineral Reserve at Stillwater Mine, on top of the best-case recovery. This dilution was added by reef domain with the goal of aligning the Proved Mineral Reserve grade with the mill head grade. The dilution is shown in Table 28. Table 28: Mining Dilution Factors and Dilution Methodology for Stillwater Mine Domain Equipment/Process Horizontal Width (ft) True Width (ft) Dilution (%) Off Shaft West Upper 1.5yd LHD 7.4 6.5 7.0 2yd LHD 8.5 7.5 7.0 4yd LHD 12 10.6 7.0 Sub-level Extraction 5.1 4.5 22.0 Off Shaft West Lower 1.5yd LHD 7.4 6.5 7.0 2yd LHD 8.5 7.5 7.0 4yd LHD 12 10.6 7.0 Sub-level Extraction 5.1 4.5 22.0 Off Shaft East-West 1.5yd LHD 7.4 6.5 7.0 2yd LHD 8.5 7.5 7.0 4yd LHD 12 10.6 7.0 Sub-level Extraction 5.1 4.5 22.0 Off Shaft East-East 1.5yd LHD 7 7 17.0 2yd LHD 7.5 7.5 17.0 4yd LHD 12 12 17.0 Sub-level Extraction 5 5 22.0 Blitz West 1.5yd LHD 7.2 6.5 11.0 2yd LHD 8.3 7.5 11.0 4yd LHD 12 10.9 11.0 Sub-level Extraction 5 4.5 22.0 Blitz 1.5yd LHD 6.7 6.5 11.0 2yd LHD 7.8 7.5 11.0 4yd LHD 12 11.6 11.0 Sub-level Extraction 4.7 4.5 22.0 Upper West East 1.5yd LHD 7.5 6 13.0 2yd LHD 9.4 7.5 13.0 4yd LHD 12 9.6 13.0 Sub-level Extraction 5 4 22.0 Dow Upper 1.5yd LHD 7.9 5.5 13.0 2yd LHD 10.8 7.5 13.0 4yd LHD 12 8.3 13.0 Sub-level Extraction 5 3.5 22.0 Dow Lower 1.5yd LHD 7.9 5.5 13.0 2yd LHD 10.8 7.5 13.0 4yd LHD 12 8.3 13.0 Sub-level Extraction 5 3.5 22.0
124 Table 29 presents the dilution factors and methodology for the two mining methods used at East Boulder Mine. This also shows the minimum horizontal width for the Ramp and Fill and the Sub-level Extraction methods. A total of 3% of unplanned hangingwall and footwall overbreak (dilution) are added to either of the minimum horizontal widths. Table 29: Mining Dilution Factors and Dilution Methodology for East Boulder Mine Domain Method Minimum Horizontal Width (ft) True Width (ft) Dilution (%) Frog Pond East and West Sub-level Extraction 6.5 5.0 3.0 Ramp and Fill 9.8 7.5 3.0 15.7.3.3 Deletion Deletion is applied to account for the loss in 2E ounces between the planned stopes and surface RoM stockpile feeing the concentrator. The two most common sources of deletion related to ore left on the floor of the stope and when reef material is left in situ when the actual stope shape deviates from the planned shape. The recent mine production reconciliation studies concluded that the loss in metal ounces is approximately 6% at Stillwater Mined and 8.5% at East Boulder Mine, which are the deletion factors applied to all blocks across Stillwater and East Boulder Mines. Deletion will be monitored and revised an annually when necessary. 15.7.3.4 Low Grade Reef Material It is common practice at both Stillwater and East Boulder Mines to ship material to the concentrator that is below the cut-off grade for high-grade ore when there is excess capacity. This low-grade reef material, internally referred to as reef sand, is mined to access high-grade reef material. The low-grade and high- grade reef material is hoisted and milled together when there is sufficient hoisting and milling capacity. At East Boulder Mine, the 2E cut-off grade was lowered from 0.05opt to align the head grade and tonnage of material milled and the Mineral Reserves. Since there is limited mill capacity at Stillwater Mine, the low-grade material that will be milled in the early years prior to achievement of steady state production level when there is unused milling capacity was included in the LoM plan underlying the Mineral Reserves. After the achievement of steady state production level, only high-grade material will be mined and milled while the low-grade material mined will not be hoisted to surface. 15.7.3.5 Mine Call Factor At this stage, no Mine Call Factors were applied to the Mineral Reserves as the loss in ounces between the stopes and the surface RoM stockpile is ascribed to deletion. Future mine to mill reconciliations at Stillwater and East Boulder Mines will establish Mine Call Factors at each of the sites which will be utilised for mine planning. Indicated Mineral Resources to Probable Mineral Reserves Conversion Factors The ore percentage has historically been the basis for the designing and scheduling of the Indicated Mineral Resources, and this was necessitated by the localised variability of the J-M Reef which leads to certain low-grade areas being left unmined for economic reasons. The lower geological confidence of the Indicated Mineral Resources when compared to Measured Mineral Resources necessitated the 125 application of the ore percentage. The ore percent is calculated in the Measured Mineral Resource areas which are supported by definition and surface drillhole data where geological block models have been updated with the most recent diamond drillhole data and structural interpretations. The ore percentage is an estimate of the fully diluted ore grade tonnage within a boundary area of a mining block compared to the total tonnage of the boundary area of the block. As an outcome of this step, stopable blocks are identified in terms of area (size) tonnage and diluted 2E content and grade in the Indicated Mineral Resources outlines. The fully diluted estimate uses the mine plan assumptions to allocate dilution according to mining method. The ore percent is additional to the mineability factor. Mineability factors for the various reef domains are derived from a comprehensive mine reconciliation process at Stillwater and East Boulder Mines. A mineability factor is calculated as the percentage of the fully diluted ore grade tonnage within a mineable area compared with the total fully diluted ore grade tonnage within the boundary area of a block. The mineable area within a block is the area that has been mined out, is within the active stopes or has sufficient grade and continuity that it should have been or will be mined. An adjustment is made to the percentage determined to compensate for negative or positive tonnage and metal ounce balances determined from historical stope reconciliation. The block mineability factors are used to perform adjustments of estimates when converting Indicated Mineral Resources to Probable Mineral Reserves. The final mineability percentage factors for each block reduce the final Probable Mineral Reserve yield in ore tons per foot of footwall lateral. Once the development and stope designs and layouts have been established in the Indicated Mineral Resource areas, Proved Mineral Reserve model statistics are applied for the derivation of production scheduled for Probable Mineral Reserve areas per block and domain. The following Proved Mineral Reserve model statistics are used: • Yield in ore tons per foot of footwall lateral driven; • Yield in ounces per foot of footwall lateral driven; and • Grade in ounces per ton. The block and domain specific statistics are applied to respective Probable Mineral Reserve blocks for which there are development designs and high-level stope outlines to estimate the Probable Mineral Reserve tonnages and grades. Life of Mine Production Scheduling and Budgeting Process Overview A formalised LoM production scheduling and budgeting process is followed for the Sibanye-Stillwater US PGM Operations, paying attention to the integrated nature of the operations. The LoM production schedules for Stillwater and Easter Boulder Mines are tested for economic viability before being aggregated for Mineral Reserve reporting. The LoM production scheduling focuses on primary access (lateral) development design and scheduling and stope design and scheduling. Each stope is evaluated in terms of a proposal, which 126 also contains reef access and stope designs, production schedules and results of the economic assessments completed. Only the stopes that are associated with positive economic outcomes are included in the aggregate LoM production schedule for each mine. The key elements accounted for in the development, stope and LoM production scheduling and budgeting processes include the following: • Milling days; • RoM ore tonnage and contained 2E metal content; • RoM ore 2E grade; • Low-grade ore (reef sand) tonnage milled; • Backfill placed; • Mining method splits with tonnages and grade; • Primary development required; • Secondary development required; • Development tonnage broken; • Total tonnage broken (ore and waste); and • Tonnage to be milled (feed). The data (tonnage, grade and development) generated by the scheduling process feeds into the Xeras system for the development of cost budgets. The budgets account for all costs associated with mining, processing, engineering maintenance, site overheads and all capital costs associated with primary development and mine-based projects. These budgets are then accounted for in the LoM Financial Model employed for the economic viability testing of the LoM plans. LoM Production Schedule for Stillwater Mine Table 30 and Figure 48 present the LoM production schedule for Stillwater Mine to FY2055. Figure 48 shows the production ramp up associated with increased output from the Stillwater East Section from FY2020 to FY2027. Production is maintained at the steady state level until FY2051 after which there is a significant reduction in tonnage to the end of the LoM in FY2055. The reduction is due to depletion of the currently scheduled Measured and Indicated Mineral Resources included in the LoM production schedule for Stillwater Mine, although there is a significant proportion of Indicated and Measured Mineral Resources not scheduled for mining. Sustained additional definition drilling will be required to upgrade parts of the Indicated Mineral Resources to Measured Mineral Resources included in the production schedule while the unscheduled remnant Measured Mineral Resources left in the historically mined areas can be brought into the production schedule at insignificant capital expenditure, when required. A 24% 2E grade reduction from the average of 0.45opt to a new average of 0.34opt is also noticeable from FY2029 onwards, coinciding with the transition from Proved to Probable Mineral Reserves. This reduction is due to the conservative approach of using a 100% ore percentage and lower grades adopted in the conversion of Indicated Mineral Resources to Probable Mineral Reserves, given the high micro-variability of the J-M Reef and the absence of definition drillhole data in these Indicated Mineral Resource areas, whereas a 70% ore percentage was used in the conversion of Measured Mineral Resource to Proved Mineral Reserves. The Qualified Person recognises the fact that the 2E grades 127 reflected in the Probable areas will improve with detailed stope planning as definition drillhole data becomes available. Table 30: LoM Production Schedule for Stillwater Mine Figure 48: LoM RoM ore production schedule for Stillwater Mine Based on the historical performance at the Stillwater Mine as well as the development results to date, mining equipment delivery schedules and available capital funding for the Stillwater East Section, the Qualified Person is of the opinion that the LoM production plan is achievable. The LoM production schedule includes the scheduled Measured and Indicated Mineral Resources and excludes Inferred Mineral Resources. FY2019 FY2020 FY2021 FY2022 FY2023 FY2024 FY2025 FY2026 FY2027 FY2028 FY2029 FY2030 FY2031 Mill Feed Tons 886 264 963 533 898 229 1 084 387 1 225 171 1 372 826 1 398 565 1 406 026 1 424 667 1 430 327 1 405 679 1 450 003 1 450 004 Feed 2E Content (oz) 409 788 409 726 381 327 470 978 525 855 623 086 633 033 675 370 667 392 609 171 488 205 471 676 463 841 Returnable 2E Content (oz) 376 395 373 624 346 557 430 229 480 893 569 022 578 284 618 295 612 455 559 243 447 095 431 111 424 425 Feed 2E Grade (opt) 0.46 0.43 0.42 0.43 0.43 0.45 0.45 0.48 0.47 0.43 0.35 0.33 0.32 FY2032 FY2033 FY2034 FY2035 FY2036 FY2037 FY2038 FY2039 FY2040 FY2041 FY2042 FY2043 FY2044 Mill Feed Tons 1 450 005 1 450 008 1 450 001 1 450 001 1 450 000 1 450 000 1 450 000 1 450 000 1 450 000 1 450 000 1 450 000 1 450 000 1 449 972 Feed 2E Content (oz) 492 505 542 482 529 295 484 177 480 784 498 058 482 830 454 597 494 294 454 891 468 984 511 537 590 375 Returnable 2E Content (oz) 450 636 497 255 487 482 445 390 442 386 458 959 444 629 418 918 455 652 418 790 431 185 470 697 544 168 Feed 2E Grade (opt) 0.34 0.37 0.37 0.33 0.33 0.34 0.33 0.31 0.34 0.31 0.32 0.35 0.41 FY2045 FY2046 FY2047 FY2048 FY2049 FY2050 FY2051 FY2052 FY2053 FY2054 FY2055 Mill Feed Tons 1 450 000 1 450 000 1 450 000 1 450 000 1 450 000 1 450 000 1 450 000 1 141 038 482 785 155 786 141 148 Feed 2E Content (oz) 495 526 486 355 474 248 471 361 508 873 532 515 502 424 383 270 162 296 53 482 48 492 Returnable 2E Content (oz) 453 302 443 684 431 969 430 665 466 426 487 749 459 563 350 013 148 040 48 562 43 953 Feed 2E Grade (opt) 0.34 0.34 0.33 0.33 0.35 0.37 0.35 0.34 0.34 0.34 0.34 Parameter Bdget BudgetActual Parameter Parameter Budget 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 0.50 0.55 0 200 000 400 000 600 000 800 000 1 000 000 1 200 000 1 400 000 1 600 000 F Y 2 0 1 9 F Y 2 0 2 0 F Y 2 0 2 1 F Y 2 0 2 2 F Y 2 0 2 3 F Y 2 0 2 4 F Y 2 0 2 5 F Y 2 0 2 6 FY 2 0 2 7 F Y 2 0 2 8 F Y 2 0 2 9 F Y 2 0 3 0 F Y 2 0 3 1 F Y 2 0 3 2 F Y 2 0 3 3 F Y 2 0 3 4 F Y 2 0 3 5 F Y 2 0 3 6 F Y 2 0 3 7 F Y 2 0 3 8 F Y 2 0 3 9 F Y 2 0 4 0 F Y 2 0 4 1 F Y 2 0 4 2 F Y 2 0 4 3 F Y 2 0 4 4 F Y 2 0 4 5 F Y 2 0 4 6 F Y 2 0 4 7 F Y 2 0 4 8 F Y 2 0 4 9 F Y 2 0 5 0 F Y 2 0 5 1 F Y 2 0 5 2 F Y 2 0 5 3 F Y 2 0 5 4 F Y 2 0 5 5 F e e d 2 E G ra d e ( o p t) M il l F e e d ( To n s) Mill Feed Tons Feed 2E Grade (opt)
128 Life of Mine Production Schedule for East Boulder Mine Table 31 and Figure 49 present the LoM production schedule for East Boulder Mine to FY2061. Figure 49 shows the progressive production ramp up as a consequence of the Fill The Mill Project to the steady state level in FY2022 until FY2049. Subsequently, there is an 7% reduction in planned annual output. With some modest capital expenditure, there are unscheduled Measured and Indicated Mineral Resources which can be brought into the LoM production schedule to main production at the steady state level. In addition, sustained additional underground definition drilling will permit the upgrade of Inferred Mineral Resources and allow sustained production at the steady state level beyond FY2049. Given the quantity of unscheduled Inferred Mineral Resources at East Boulder Mine, it is reasonable to expect that the definition drilling will permit the upgrading of significant Inferred Mineral Resources and subsequent conversion to Mineral Reserves. Another key attribute of the production profile is the consistency in 2E grades, which reflects less grade variability compared to Stillwater Mine. The Qualified Person considers the forecasted production levels achievable as mining equipment and manpower required to meet the increased development and stoping requirements have already mobilised to the mine. Table 31: LoM Production Schedule for East Boulder Mine FY2019 FY2020 FY2021 FY2022 FY2023 FY2024 FY2025 FY2026 FY2027 FY2028 FY2029 FY2030 FY2031 FY2032 FY2033 Mill Feed Tons 669 169 679 270 720 953 791 970 777 245 786 900 784 750 784 750 784 750 786 900 784 750 784 750 784 750 786 900 784 750 Feed 2E Content (oz) 238 598 253 541 248 473 287 687 288 804 287 225 286 441 287 225 286 441 287 225 286 441 287 225 286 441 287 278 286 493 Returnable 2E Content (oz) 217 579 229 442 223 842 259 882 260 891 259 464 258 755 259 464 258 755 259 464 258 755 259 464 258 755 259 512 258 803 Feed 2E Grade (opt) 0.36 0.37 0.34 0.36 0.37 0.37 0.37 0.37 0.37 0.37 0.37 0.37 0.37 0.37 0.37 FY2034 FY2035 FY2036 FY2037 FY2038 FY2039 FY2040 FY2041 FY2042 FY2043 FY2044 FY2045 FY2046 FY2047 FY2048 Mill Feed Tons 784 750 784 750 786 900 784 750 784 750 784 750 786 900 784 750 784 750 784 750 786 900 784 750 784 750 784 750 786 900 Feed 2E Content (oz) 287 278 286 493 280 050 279 097 286 125 297 069 280 664 280 584 281 353 280 584 281 947 280 584 281 353 280 584 281 947 Returnable 2E Content (oz) 259 512 258 803 252 983 252 122 258 471 268 357 253 537 253 465 254 159 253 465 254 696 253 465 254 159 253 465 254 696 Feed 2E Grade (opt) 0.37 0.37 0.36 0.36 0.36 0.38 0.36 0.36 0.36 0.36 0.36 0.36 0.36 0.36 0.36 FY2049 FY2050 FY2051 FY2052 FY2053 FY2054 FY2055 FY2056 FY2057 FY2058 FY2059 FY2060 FY2061 Mill Feed Tons 784 750 730 000 730 000 725 861 725 861 725 861 725 861 725 861 725 861 725 861 725 861 725 861 725 861 Feed 2E Content (oz) 280 584 261 724 253 927 257 490 257 490 257 490 257 490 257 490 257 490 257 490 257 490 257 490 257 490 Returnable 2E Content (oz) 253 465 236 427 229 385 232 603 232 603 232 603 232 603 232 603 232 603 232 603 232 603 232 603 232 603 Feed 2E Grade (opt) 0.36 0.36 0.35 0.35 0.35 0.35 0.35 0.35 0.35 0.35 0.35 0.35 0.35 Parameter Parameter Parameter Actual Budget Budget Budget 129 Figure 49: LoM Production Schedule for East Boulder Mine Mining Equipment Stillwater Mine 15.9.1.1 Stillwater West Section Operations in the Stillwater West Section are mechanised, employing various pieces of equipment as listed in Table 32. For this section, the mine makes use of 4.0 cubic yard and 6.0 cubic yard LHDs for infrastructure development and 2.0 cubic yard LHDs for operations on the reef including reef development and stope ore removal. Other key elements of the current fleet are face drill rigs, bolters and dump trucks. These are further supported by numerous utility and transport units. The Qualified Person is satisfied that, accounting for the geographical separation of the stoping and development areas and the daily production called for, the Stillwater East Section has sufficient equipment to meet current production targets. Table 32: Stillwater West Section Current Mechanised Mining Equipment Quantities Equipment Description Number of Existing Units Mechanised Bolters 11 CMAC Bolters 36 Face Drill Rigs 33 LHDs 75 Dump Trucks 24 Utility Vehicles 221 Tractors 6 Locomotives 13 Total 419 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 0.50 0.55 0 100 000 200 000 300 000 400 000 500 000 600 000 700 000 800 000 900 000 F Y 2 0 1 9 F Y 2 0 2 0 F Y 2 0 2 1 F Y 2 0 2 2 FY 2 0 2 3 F Y 2 0 2 4 F Y 2 0 2 5 F Y 2 0 2 6 F Y 2 0 2 7 F Y 2 0 2 8 F Y 2 0 2 9 F Y 2 0 3 0 F Y 2 0 3 1 F Y 2 0 3 2 F Y 2 0 3 3 F Y 2 0 3 4 FY 2 0 3 5 F Y 2 0 3 6 F Y 2 0 3 7 F Y 2 0 3 8 F Y 2 0 3 9 F Y 2 0 4 0 F Y 2 0 4 1 F Y 2 0 4 2 F Y 2 0 4 3 F Y 2 0 4 4 F Y 2 0 4 5 F Y 2 0 4 6 F Y 2 0 4 7 F Y 2 0 4 8 F Y 2 0 4 9 F Y 2 0 5 0 F Y 2 0 5 1 F Y 2 0 5 2 F Y 2 0 5 3 F Y 2 0 5 4 F Y 2 0 5 5 F Y 2 0 5 6 F Y 2 0 5 7 F Y 2 0 5 8 F Y 2 0 5 9 FY 2 0 6 0 F Y 2 0 6 1 F e e d P d + P t G ra d e ( o p t) M il l F e e d ( To n s) Mill Feed Tons Feed 2E Grade (opt) 130 A combination of vertical hoisting (via the shaft) and tramming (via trains and locomotives) is employed for the transport of ore and waste from the underground workings to the processing facility on surface. Currently, 60% of ore generated underground at the Stillwater Mine is hoisted via the shaft with the remainder being transported via train. The quantity of ore transported by rail will increase as the production levels at the Stillwater East Section increase. 15.9.1.2 Stillwater East Section The Stillwater East Section is currently under development and the mining equipment listed in Table 33 is currently being employed for development and ore production. The planned ore production from the Stillwater East Section will be supported by additional mechanised units to be procured over the next two years for development and production as indicated in Table 33. The planned development and production build-up and the resulting mechanised equipment requirements are supported by a detailed capital expenditure and equipment procurement schedule, providing for mining equipment procurement of approximately US$156 million over the FY2022 to FY2026 period. The Qualified Person is of the opinion that sufficient equipment has been scheduled for procurement over the next five years to meet the expanding production levels planned for the Stillwater East Section. Table 33: Stillwater East Section Current Mechanised Mining Equipment Quantities Equipment Description Number of Existing Units Mechanised Bolters 9 CMAC Bolters 12 Face Drill Rigs 12 LHDs 26 Dump Trucks 7 Utility Vehicles 39 Tractors 0 Locomotives 7 Total 112 East Boulder Mine Operations at East Boulder Mine are also mechanised, employing the equipment as listed in Table 34. The mine makes use of 4.0 cubic yard and 6.0 cubic yard LHDs for infrastructure development and 2.0 cubic yard LHDs for production mining operations on the reef, including development and stope ore removal. Table 34: East Boulder Mine Mechanised Mining Equipment Quantities Equipment Description Number of Existing Units Mechanised Bolter 5 CMAC Bolter 8 Face Drill Rigs 16 LHDs 34 Dump Trucks 7 Utility Supply Flatbeds 13 Tractor 13 Forklifts 8 131 Equipment Description Number of Existing Units Mechanised Bolter 5 Skidsteer 5 Locomotives 9 Mine Transportation 62 Road Maintenance 4 Total 176 The Qualified Person is of the opinion that, accounting for the geographical separation of the stoping and development areas and the daily production called for in the LoM production plan, the mine currently has sufficient equipment to meet production targets. Logistics Stillwater Mine A total of eleven adits have been driven and access underground workings at the Stillwater Mine; six are main accesses and intakes, four are dedicated exhausts, and one is an auxiliary drift. The main rail haulage adits are the 5000W and 5000E Levels. Ore is dropped down from the upper levels via a series of raise-bored ore and waste passes to transfer boxes on 5000W Level from where the rock is railed to the mine portal by diesel locomotives. The rail cars discharge ore or waste into a purpose-built tip that dumps into a haul truck. The haul truck dumps the ore onto a RoM stockpile ahead of the concentrator. The waste rock is transported to the East Side Waste Rock Dump. For the Stillwater East Mine, ore and waste is dropped down from the upper levels via a series of AlimakTM ore and waste passes to transfer boxes on the 5000E Level from where the rock is railed to the mine portal by diesel locomotives. The rail cars discharge ore or waste into two dumps that drop the material into a “box” from where surface loaders pick up the material and load haul trucks that transport and dump the ore onto a RoM stockpile ahead of the concentrator or haul the waste to the East Side Waste Rock Dump. Ore and waste rock from the levels below the portal adit of the 5000 Level is hoisted to surface via the Vertical Shaft. Ore and waste rock is transferred from all the levels above 3500W and below 5000 Level via a series of raise-bored ore and waste rock passes to the main transfer boxes on the 3500W Rail Level. Rock material (ore or waste) is hauled by tandem 20-ton diesel locomotives with eight to eleven ore cars per train (either nominal 10 ton or 9-ton capacity per car) and discharged into the mine tip on 3500 Level which reports to the shaft. All broken rock from the rock passes reports to the main jaw crusher which in turn feeds, via an apron feeder, onto the main conveyor belt on 3100W Level. The conveyor belt feeds into the main surge box prior to loading into measuring flasks at the skip boxes. The ore and waste rock is hoisted separately to surface using two 10-ton skips and deposited on separate stockpiles. There is sufficient available hoisting time to meet the LoM production requirements. A double deck 50-person capacity service cage is also available in the shaft that can move men and material from surface to service all levels between 4400 Level and 3100 Level.
132 A fully equipped ramp has been developed down to the 1600 Level, which is currently the lowest level on the mine. The ramp is used to haul production from the 2900, 2600, and 2300 Levels by bringing rock to the loading level of the shaft on 3500 Level. All ore and waste rock generated between 1600 Level and 2900 Level gravitates via rock passes down to lower levels where it is loaded via hydraulic chutes into articulated 30-ton haul trucks. Thereafter, the rock material is hauled to 2600 Level and discharged into the appropriate tips, which feed the 2500 Level chutes. The ore and waste rock is then loaded from the 2500 Level ore and waste chutes and hauled up the ramp to the 3500 Level by 42-ton diesel powered haul trucks. The various adits and the Vertical Shaft are used for the supply of all services to the underground operations, including compressed air, water supply, power, sandfill, and the transport of men, materials, equipment, diesel, explosives and rock. The Qualified Person is of the view that logistics employed at the Stillwater West Section for the transport of men, material and rock have sufficient capacity to meet the planned production levels. Considering the current and future design logistics capacities for the Stillwater East Section, there will be sufficient logistical support to meet the planned increases in production in this section. East Boulder Mine East Boulder Mine is accessed by two parallel tunnels from the surface portal, with the 6500 Level main access level equipped with 90lb rail for the transport of personnel, materials and rock to and from the mine. All levels above and below this access level are operated as trackless mining sections. Broken rock material (ore and waste) from the upper levels above the 9100 Level is transported to internal tips within each of the independent ramp systems. Ore and waste rock from the upper levels is gravitated to the main 6500 Level rail haulage via drop raises and Alimaks to near vertical ore and waste rock passes to transfer boxes on the 6500 Level from where the rock is railed to the surface by diesel locomotives. There are some internal transfers on the 7500, 7900 and 8500 Levels to place ore and waste into the Life of Mine (LoM) pass systems. All rock material on the upper levels passes through a grizzly to prevent blockage of the rock passes. Once on surface, the rail cars discharge the ore or waste material into dedicated tips from where ore is conveyed to the concentrator stockpile and waste is loaded out for tailings dam wall construction. The twin 6500 Level access tunnels (Tunnel 1 and 2) are used for the supply of all services underground, water, power, sandfill, and the transport of personnel, materials, equipment, diesel, explosives and rock. Compressed air is supplied by underground compressors near the main shop complex and all compressed air passes through a dryer to remove excess water from the air stream. During FY2019 and FY2020, Tunnel 2 was subjected to a rail upgrade to improve train cycle times required to meet the increasing levels of production (ore and waste) associated with the Fill the Mill Project. This work was completed after an 18-months period in June 2020. 133 The Qualified Person is of the opinion that, with the completion of the Tunnel 2 rail upgrade, the logistics employed at East Boulder Mine for the transport of personnel, material and rock are adequate to meet the planned production levels. Underground Mine Services Stillwater Mine 15.11.1.1 Overview Stillwater Mine continues to develop its infrastructure in FY2022 and beyond to accommodate the increased mining footprint resulting from the Stillwater East Section expansion. The infrastructure currently in place is being expanded to allow the mine to execute its LoM plan. 15.11.1.2 Ventilation Access and service adits and shafts are utilised for the ventilation of underground operations. In the Stillwater West Section, the openings are split between: • Intakes: Stillwater Shaft, 4800W Portal, 5000W Portal, 5500W Portal, and 5900 Portal; • Exhaust openings: 5400E Portal, 5400E Raisebore breakouts (x2), 5150W Portal, 5300W Portal, 6600W Alimak to Surface breakout, and the 6600W breakout adit. In the Stillwater East Section, there are two main intakes (5000E Rail Portal and 5000E Portal) and two 56E13800 Alimaks to Surface Breakouts for exhaust. Ventilation temperature is planned to be conducive to optimum machine and personnel productivity and this will be achieved by using propane bulk air heaters installed at the main intake airways to be operated in winter to limit water freezing. The maximum temperature for operations underground is targeted to be less than 85°F wet bulb. Stillwater Mine draws approximately 2 100 000 cubic feet per minute (cfm) of ventilation air through the exhaust system via fourteen 400hp main exhaust fans situated at various ventilation raises and adits. Ventilation flow is supplemented by booster fans ranging from 30hp to 150hp to create a mine-wide negative pressure system. Stope ventilation is achieved with 30hp to 75hp axial fans in conjunction with rigid and lay-flat ducting. Whenever possible, through ventilation is achieved by establishing a raise from the sill level of the stope to the level above. This allows a split of air from the primary circuit to flow through the stopes. Total fan power installed in the primary system is 6 300hp. There are additional development forcing fans in all the primary development sections. The development ends employ 75hp to 100hp fans which may be placed in series on longer development drives. Four 400hp main fans are utilised for the Stillwater East Section, with the remainder utilised for the Stillwater West Section. Approximately 680 000cfm is currently supplied to the Stillwater East Section. The long-term production goals with diesel equipment require an increase to 1 300 000cfm which will be supplied by eight 700hp main fans, the connection of the Benbow Decline to the Stillwater East Section 134 and another set of dual Alimak raises to surface at 56E22500. Several ventilation raises are planned for development in various strategic areas of the Stillwater West and East Section and commissioning during FY2022 and FY2023. 15.11.1.3 Mine Dewatering The lowest level at Stillwater Mine is the 1400W Level Decline and the lowest operational level is the 1600 West Level. Stillwater Mine has installed a series of “leapfrog” interim dams and pumps for the removal of waste and fissure water from these low points. Water is pumped from one pump station/sump up to the next in consecutive lifts to bring the water out of the mine via the 1900W Level Pump Station. Drain water is collected in sumps in the various haulages and pumped to the main pumps station or a drain hole on that level to ensure haulages and declines are kept dry. The 1900W Level Pump Station comprises six main pumps which pump water to an intermediate pump station on the 2500W Level, which pumps to a series of sumps on the 3100W Level, and water is then pumped from this intermediate pump station to the 4400W Level Pump Station. This water is then pumped up to the 5300W Level Surge Reservoir from where it is gravity fed to the West Clarifier on surface. Water from areas above the 5000E Level at the Stillwater East Section reports to the East Clarifier on surface while remainder of the water reports to the West clarifier through the 5300W level surge reservoir. A disk filtration system installed on surface in FY2020 was commissioned in Q1 FY2021 which was designed to treat all water disposed of via percolation and the Land Application and Disposal facility adjacent to the Hertzler Tailings Storage Facility to comply with recently issued water disposal regulations. The current pumping capacity of the Stillwater West Section is approximately 1 600gal per minute and is adequate for handling the expected amount of mine inflow water. In order to improve the management, maintenance and cost effectiveness of the pumping system, Stillwater Mine has approved a new high-pressure pumping system to reduce the number of sumps and pumps in the future. This will also reduce the amount of cascade feed and the effective head pumped. There is a proposal to install a single lift dewatering station at the 3200W Level to pump water from the 3200 Level to the 5300W Level Surge Reservoir or conversely, directly to the west clarifier. This will eliminate the 3100W Level and 4400W Level Pump Stations. The Qualified Person is of the opinion that Stillwater Mine has an appropriate mine dewatering system, which will be further enhanced on the completion of the upgrade discussed above, and that the dewatering system can handle all water inflows into the mine. 15.11.1.4 Compressed Air The installed compressed air system at Stillwater Mine consists of eleven stationary compressors for 19 600cfm of capacity. There are six compressors on the east side and five on the west side. These compressors are all located on surface and are tied into the total mine system by underground piping and a 12-inch diameter on-surface trunk line between the east side compressor house and the west 135 side Loci Barn compressor house. Compressed air volumes are being increased as production ramps up in the Stillwater East Section. In FY2021, an engineering study was launched with the inhouse projects team and executed by Nordmin Engineering to further delineate future needs. The compressed air service map for Stillwater Mine is shown in Figure 50. Figure 50: Stillwater Mine Compressed Air Service Map 15.11.1.5 Service Water Upgrades to the present service water system will provide the Stillwater East Section with approximately 550gal per minute of service water, which is sufficient for the projected production from this section. The 550gal per minute was calculated by taking historical Stillwater Mine service water quantities and correlating with the total tons of rock broken during the same period. This calculation took into consideration all sandfill, diamond drilling, mining and miscellaneous water uses required for the production at Stillwater Mine. The present surface pump house delivers service water to the Stillwater East Section and, as the production in this section continues to ramp up, the service water demand will increase. To meet the increased demand, the service water piping was upgraded to 8-inch diameter Schedule 40 steel pipe.
136 The 8-inch steel pipe was installed from the 5000E Portal through the 5000E Drive (TBM tunnel) to the bottom of the 5600E15-200 Utilities boreholes in Q1 FY2021. An upgrade of the three vertical turbine pumps motors to 100hp in the surface pump house was required to meet the ultimate steady-state water demand. These upgrades, along with the 8-inch piping upgrade, allow the surface pumps to deliver 550gal per minute of water to the 5600E15-200 Drill Water Reservoir (DWR), which was commissioned in May 2020. Additional service water reservoirs are planned as follows: • 6000E15-200 DWR will be commissioned during FY2022; and • 6400E15-200 DWR will be commissioned during FY2023. A schematic diagram showing the Stillwater East Section service water reticulation is shown in Figure 51. Figure 51: Stillwater East Section Service Water Reticulation East Boulder Mine 137 15.11.2.1 Overview East Boulder Mine continues to increase its mining footprint and development continues upwards to generate more Mineral Reserves. This development is supported by the necessary mine services and infrastructure, which includes the following: • 6500, 7200 and 8200 Level sand plants; • An optimised ventilation system; • Infrastructure for the 72740-ramp system; and • Infrastructure required for the development of the 7500 and 7200 Footwall Levels and the Frog Pond incline. 15.11.2.2 Ventilation East Boulder Mine draws 550 000cfm of air to ventilate the underground operations via four main mains fans, 400hp exhaust fans located at the Brownlee Ventilation Raises (two) and Simpson Creek Raise and one 600hp fan located at the Graham Creek Raise. The air is exhausted via two vertical raises to the Frog Pond adit, a raise to Simpsons Creek adit and the Graham Creek Raise. Additional forcing fans are utilised in primary development sections. Stope ventilation is achieved with 40hp to 100hp axial fans in conjunction with rigid and lay-flat ducting. Whenever possible, through ventilation is achieved by establishing a raise from the sill level of the stope to the level above. This allows separate and unique air from the primary circuit to flow through the stopes. Prior to the Fill The Mill Project, the East Boulder Mine ventilation system serviced four development sections and six stope production sections. The Fill The Mill Project added a fifth development section and a seventh stoping section and the ventilation system has been upgraded by developing an incline to surface that holes into the pre-existing Frog Pond adit. In addition, circulating volumes have been increased to 600 000cfm of exhaust air, taking advantage of the redundancy in the existing fan system, which was operating at 60% capacity. Therefore, there was no need to increase the number of fans although, in the medium term, there is a plan to upgrade the Graham Creek fan to 850hp from the current 600hp. The mine uses a negative ventilation draw system, which minimises the use of ventilation doors and reduces air leakage and is, therefore, more power efficient than the forced ventilation system previously implemented at the mine. The reduction in the number of ventilation doors in the main traveling drives to seven has saved the time lost in traversing the airlocks and eliminating potential collision incidents. Air entering the mine on the 6500 Level is heated via two propane bulk air heaters in the winter to prevent freezing of pipes and to ensure productive working temperatures. Carbon monoxide monitors and airflow monitors are positioned at strategic positions in the mine to detect fire in the underground sections, which is a back-up to a stench smell release system in place for the operators in remote areas. The mine also employs real-time diesel particulate matter sensors at various underground locations to better the healthy environment for the employees. 138 The Qualified Person is satisfied with the current ventilation system which provides air flow that is adequate for the mine’s needs. 15.11.2.3 Mine Dewatering Mining operations are primarily situated above the main adit level allowing for water drainage from the active sites and, therefore, water pumping is not a major challenge. Furthermore, water inflow from fissures and underground aquifers is minimal. Ramp development below the 6500 Level is equipped with normal mobile pumps and cascade sump/pumps to bring the water to the 6500 Level. Water management focus is primarily to ensure that there is adequate infrastructure to manage service water and wastewater from the underground fill. The pumping capacity of the mine is approximately 396gal per minute from the main pump station on the 6500 Level, which exceeds the historical and current water flow rates of less than 200gal per minute. The Qualified Person is satisfied with the pumping capacity at the mine, which meets the current and future needs of the mine. 15.11.2.4 Compressed Air The present compressed air system at East Boulder Mine consists of five stationary compressors and a mine wide distribution system. These compressors are all located underground and are tied into the mine compressed air system by underground piping and a controller, and deliver compressed air based on demand. Air is piped via an 8-inch diameter main trunk on the 6500 Level, 6-inch diameter pipes up each ramp, and 6-inch or 8-inch lines on each level. There is also a dedicated 10-inch trunk that runs from the compressors near the central shop to the 7500 Level. All the pipes are interconnected. Each compressor is rated at 500hp and can deliver 1 750cfm at 125psig at the 6500 Level elevation. Collectively, all compressors can deliver over 8 700cfm but only four compressors are required to run at peak demand, with normal duty requiring three compressors run online and with the fifth providing the required redundancy. A compressed air dryer was commissioned on 6500 Level in early FY2020 to reduce water in the air lines. A 10-inch diameter pipeline loop from the 7500 Level up to the 8200 Level was installed in FY2020 to increase storage capacity above the 7500 Level. A 200 HP satellite compressor was added in FY2021 to service a long hole drilling machine, with three more satellite compressors to be added and installed at long hole drilling locations. In addition, studies on long-term engineering and option planning started in FY2021 and scheduled for completion in FY2022 will which more closely define the long-term compressed air requirements and strategy. As a result, the Qualified Person is satisfied with the compressed air system in place at East Boulder Mine. The compressed air service map for East Boulder Mine is shown in Figure 52. 139 Figure 52: East Boulder Mine Compressed Air Distribution System 15.11.2.5 Service Water The current service water system consists of multiple DWRs situated on each level underground (Figure 53). The DWR system is fed from the riser pump located at the surface clarifier, which receives the return water from the mining activities underground. The clarified water is pumped underground via a pipeline from the clarifier to the 6500 Level DWR from where it is pumped vertically to the DWRs at the higher levels in the mine in a cascading fashion – DWRs are located at the 6500, 6700, 6900, 7200, 7500, 7900, 8200, 8500 and 8800 Levels. Clean Portal Water is also distributed to the 6500 DWR via a pipeline in Tunnel 1 from a sump inside Portal 1. The future water distribution plan provides for one more DWR at the 9100 Level. The DWRs are equipped with pump skids that have two pumps per skid, each pump delivering 300gal per minute at 350ft of head. The 7900, 8200, 8500 and 8800 DWRs are controlled via variable frequency drives (VFDs) and 40hp pumps, whereas the rest of the DWRs have 125hp direct feed pumps. Each system is sufficient and the DWR planned will be constructed with 40hp pumps and VFDs. The Qualified Person is satisfied with the current service water system, which provides sufficient service water to the mining operations, and no major additions are required. The planned upgrades will ensure the mine has sufficient service water for to the expanded operations.
140 Figure 53: East Boulder Mine Drill Water Reservoir Layout Manpower Table 35 and Table 36 show the LoM manpower plans for Stillwater and East Boulder Mines, respectively. A 13% increase in total manpower is planned in FY2022 to bolster the mining, technical services and administration, surface operations and engineering and maintenance complements for the sustainability of the steady state production levels following the conclusion of the Fill The Mill Project at East Boulder Mine. However, the manpower figures are forecast to remain at the FY2022 levels for the remainder of the LoM. Total manpower increases ranging from 4% to 9% are planned at Stillwater Mine 141 from FY2022 to FY2024 because of the expansion of the mining complement required to achieve the production ramp up at the Stillwater East Section. The manpower levels are forecast to remain relatively stable from FY2025 to FY2046 as the operations approach and attain the steady state production level after which the manpower figures decline in response to declining tonnage planned in the LoM production plan. Table 35: LoM Manpower Plan for Stillwater Mine FY2019 FY2020 FY2021 FY2022 FY2023 FY2024 FY2025 FY2026 FY2027 FY2028 FY2029 FY2030 FY2031 Mining 761 777 870 772 839 944 918 888 848 816 812 820 822 Engineering Maintenance 169 191 148 209 234 243 243 243 243 243 243 243 243 Technical Services & Admin 99 123 147 228 291 291 291 291 291 291 291 291 291 Concentrator 42 42 43 52 54 54 54 54 54 54 54 54 54 Surface 19 27 28 24 28 28 28 28 28 28 28 28 28 Total Mine Site 1 090 1 159 1 236 1 285 1 446 1 560 1 534 1 504 1 464 1 432 1 428 1 436 1 438 FY2032 FY2033 FY2034 FY2035 FY2036 FY2037 FY2038 FY2039 FY2040 FY2041 FY2042 FY2043 FY2044 Mining 824 821 825 824 823 814 814 814 813 814 770 740 707 Engineering Maintenance 243 243 243 243 243 243 243 243 243 243 243 222 199 Technical Services & Admin 291 291 291 291 291 291 291 291 291 291 291 291 291 Concentrator 54 54 54 54 54 54 54 54 54 54 54 54 54 Surface 28 28 28 28 28 28 28 28 28 28 28 28 28 Total Mine Site 1 440 1 437 1 441 1 440 1 439 1 430 1 430 1 430 1 429 1 430 1 386 1 335 1 279 FY2045 FY2046 FY2047 FY2048 FY2049 FY2050 FY2051 FY2052 FY2053 FY2054 FY2055 Mining 692 665 576 576 576 559 559 494 361 260 190 - - Engineering Maintenance 199 194 194 194 194 194 194 194 194 194 194 - - Technical Services & Admin 291 291 291 291 276 276 276 266 256 222 205 - - Concentrator 54 54 54 54 54 54 54 54 54 54 54 - - Surface 28 28 28 28 28 28 28 28 28 28 28 - - Total Mine Site 1 264 1 232 1 143 1 143 1 128 1 111 1 111 1 036 893 758 671 - - Description Budget Description Budget Actual Budget Description 142 Table 36: LoM Manpower Plan for East Boulder Mine The Qualified Person noted that higher mining productivities are forecast at East Boulder Mine than the steady state productivity levels at Stillwater Mine when viewed in terms of tonnage generated per number of mining employees. However, the planned mining manpower levels for Stillwater and East Boulder Mines are aligned to the actual levels of productivity achieved previously. Accordingly, the Qualified Person is satisfied with the current manpower plans for Stillwater and East Boulder Mines. FY2019 FY2020 FY2021 FY2022 FY2023 FY2024 FY2025 FY2026 FY2027 FY2028 FY2029 FY2030 FY2031 FY2032 FY2033 Mining 282 281 294 326 325 327 327 327 327 327 327 327 327 327 327 Engineering Maintenance 64 71 71 79 79 79 79 79 79 79 79 79 79 79 79 Technical Services & Admin 41 44 46 57 57 58 58 58 58 58 58 58 58 58 58 Concentrator 31 29 30 34 34 33 34 34 34 34 34 34 34 34 34 Surface 18 18 16 20 20 20 20 20 20 20 20 20 20 20 20 Total Mine Site 436 443 457 516 515 517 518 518 518 518 518 518 518 518 518 FY2034 FY2035 FY2036 FY2037 FY2038 FY2039 FY2040 FY2041 FY2042 FY2043 FY2044 FY2045 FY2046 FY2047 FY2048 Mining 327 327 327 327 327 327 327 327 327 327 327 327 327 327 329 Engineering Maintenance 79 79 79 79 79 79 79 79 79 79 79 79 79 79 79 Technical Services & Admin 58 58 58 58 58 58 58 58 58 58 58 58 58 58 58 Concentrator 34 34 34 34 34 34 34 34 34 34 34 34 34 34 34 Surface 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 Total Mine Site 518 518 518 518 518 518 518 518 518 518 518 518 518 518 520 FY2049 FY2050 FY2051 FY2052 FY2053 FY2054 FY2055 FY2056 FY2057 FY2058 FY2059 FY2060 FY2061 FY2062 FY2063 Mining 331 333 335 337 339 341 343 345 347 345 348 335 301 303 305 Engineering Maintenance 79 79 79 79 79 79 79 79 79 79 79 79 79 79 79 Technical Services & Admin 58 58 58 58 58 58 58 58 58 58 58 58 58 58 58 Concentrator 34 34 34 34 34 34 34 34 34 34 34 34 34 34 34 Surface 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 Total Mine Site 522 524 526 528 530 532 534 536 538 536 539 526 492 494 496 Description Actual Description Description Budget Budget Budget 143 PROCESSING AND RECOVERY Mineral Processing Methods Background Ore processing plants at Stillwater and East Boulder Mines and the smelter and base metal refinery at the Columbus Metallurgical Complex have been in continuous operation for decades. All metallurgical processes and technology in place at the ore processing, smelting and refining facilities are appropriate, well-proven and aligned to norms and practices in the PGM sectors. The processing methods were selected based on metallurgical testwork carried out as part of feasibility studies at the time of development. However, results of the testwork have been superseded by actual operational data and experience accumulated over several years of continuous successful operation of these facilities. Accordingly, there are no plans to introduce new processing technology at the processing facilities. The plant capacity upgrades at Stillwater Concentrator and the metallurgical complex are based on existing technology and process flowsheets. The plans to maximise installed capacity at the East Boulder Concentrator is similarly based on existing and proven technology. Ore Processing Stillwater Concentrator 16.2.1.1 Plant Capacity The PGM concentrator at Stillwater Mine was commissioned in 1987 as a 500-ton per operating day conventional crushing, milling and flotation plant producing a PGM-base metal sulphide concentrate suitable for downstream smelting and refining. Following several process modifications and expansions, the concentrator capacity increased to approximately 3 100 tons per operating day by FY2020. The concentrator has historically operated on a ten-day or eleven-day fortnight basis and has been switched off every second weekend resulting in approximately 75% utilisation. This was required to maintain the balance with mining volumes of 750 000 tons per year at the time, but the concentrator currently operates on a continuous basis with a target utilisation of 92% due to the increased tonnage delivered from the mine in recent years. At the 92% utilisation, the plant capacity before expansion is equivalent to approximately 1.04 million tons per year. A significant capital expansion project currently underway and due to be finalised and commissioned in late (Q3-Q4) FY2022 will result in an operational capacity increasing to 4 110 tons per operating day (i.e., 1.45 million tons per year) at full utilisation. This will accommodate additional material from the Stillwater East Section. The following areas of the concentrator are being upgraded with a view to increasing tonnage throughput capacity: • Milling Section: A new SAG mill, a new ball mill and new pebble crushing facility, will be installed to replace the current comminution facility, which will be decommissioned. The new milling building will be located immediately adjacent to the current structure and is due to be
144 commissioned in late (Q3-Q4) FY2022 and capital expenditure has been budgeted for the completion of this section during FY2022; • Flotation Section: Associated with the milling circuit replacement, the flash flotation cells will also be replaced with new cells. The remainder of the flotation circuit requires minimal expansion, with the addition of a few cleaner cells, and the increase in capacity of some of the float column cells. The existing float plant building has sufficient capacity and infrastructure to accommodate the minor expansions required. This upgraded circuit is planned to be commissioned in parallel with the new milling circuit in late FY2022; • Tailings Section: Confirmatory work is currently underway, but indications are that the tailings section has sufficient capacity to accommodate the increased throughput in terms of thickening, slurry pumps and lines and return water pumping and lines; and • Concentrate Handling: Upgrade of the concentrate handling facility was commissioned at the end of FY2020. The concentrate thickener has been replaced and a new stock tank and filter press have been installed. The dry concentrate bin has also been replaced to allow delivery into the new side-tipping trucks, which have been implemented for the transportation of the concentrate from the mine to the Columbus Metallurgical Complex. These same trucks return with slag and reverts for reprocessing. 16.2.1.2 Manpower Requirements The plant staffing comprises four crews operating on two 12-hour shifts of one Supervisor, four Operators and a Tailings Storage Facility Operator. Current budget staff is twelve Maintenance (Mechanical) Technicians to support Concentrator, Surface Operations, Paste Plant, Water Treatment, and Building Maintenance and these technicians follow the 24-hour per 7-day week shift rotation system. There are four Electrical Technicians with the same area of responsibility as Concentrator Maintenance Technicians but working on a seven-day per week basis. Major and routine planned maintenance is scheduled on a regular basis to ensure the plant mechanical availability of 92% is maintained. 16.2.1.3 Process Description The concentrator currently receives ore from the Off-shaft and Upper West areas of the Stillwater West Section and Blitz West area of the Stillwater East Section as well as slag and brick recycle materials from the smelter. Smelter slag and brick recycle materials are delivered to the primary crushing area and are campaign-treated through the concentrator. A typical slag campaign would last 24 hours and would entail process changes such as different reagent dosages, lower throughput and shutting down the flash float circuit. Approximately 75% to 80% recovery of contained 2E is the sustainable target for these campaigns. The concentrator has previously processed approximately 1.1 million tons per year of RoM ore feed at a 92% total 2E recovery from this material (FY2020). The current expansion is based on the existing process flow diagram which is presented in Figure 54. The process comprises open circuit crushing followed by two stages of milling, with the sized product being delivered to the flotation circuit. Various stages of flotation including roughing, cleaning and scavenging in addition to a regrind circuit ensure that recovery is optimised and concentrate grades suitable for smelting are realised. 145 Figure 54: Block Flow Diagram of the Stillwater Concentrator 16.2.1.4 Production Plan The recent history and budget operational parameters for the concentrator are presented together with the LoM production plan in Table 37, Figure 55 and Figure 56. The FY2019, FY2020 and FY2021 data presented reflects the actual annual performance whilst the FY2022 to FY2055 data represents current budget targets. The current operational methods and capacities are adequate. Metallurgical efficiencies projected have not been obtained historically, but as a result of the process upgrades underway and the minor increases projected, are deemed reasonable budget targets. Table 37: Stillwater Concentrator Actual and Forecast LoM Operational Throughput and Outputs FY2019 FY2020 FY2021 FY2022 FY2023 FY2024 FY2025 FY2026 FY2027 FY2028 FY2029 FY2030 FY2031 Total Feed tons 955 940 981 333 936 439 1 132 642 1 275 472 1 350 816 1 302 836 1 404 651 1 447 597 1 442 296 1 450 032 1 355 137 1 450 004 Concentrate Produced tons 18 773 21 815 22 703 24 749 27 900 29 588 28 567 30 787 31 873 31 714 31 851 29 757 31 837 2E Recovery % 91.39 91.86 91.62 92.24 92.31 92.00 92.09 92.05 92.48 92.35 92.26 92.23 92.22 2E Metal Produced oz 376 395 373 618 346 569 430 229 480 893 567 426 569 420 601 823 616 095 538 139 475 913 438 392 459 831 FY2032 FY2033 FY2034 FY2035 FY2036 FY2037 FY2038 FY2039 FY2040 FY2041 FY2042 FY2043 FY2044 Total Feed tons 1 450 009 1 444 692 1 449 980 1 449 957 1 450 000 1 450 000 1 450 000 1 450 000 1 450 000 1 450 000 1 450 000 1 450 000 1 442 946 Concentrate Produced tons 31 842 31 785 31 955 31 921 31 985 32 013 32 016 32 043 32 065 32 065 32 048 31 960 31 742 2E Recovery % 92.23 92.40 92.56 92.46 92.64 92.73 92.74 92.81 92.88 92.88 92.83 92.57 92.39 2E Metal Produced oz 464 953 464 762 455 646 437 498 459 848 485 286 476 041 449 571 443 632 438 374 449 542 444 024 445 350 FY2045 FY2046 FY2047 FY2048 FY2049 FY2050 FY2051 FY2052 FY2053 FY2054 FY2055 Total Feed tons 1 450 000 1 450 000 1 450 865 1 450 000 1 450 000 1 450 000 1 357 731 945 728 496 730 316 266 256 635 Concentrate Produced tons 31 812 31 702 31 741 31 768 31 751 31 798 29 784 20 757 10 894 6 952 5 646 2E Recovery % 92.14 91.83 91.88 92.02 91.97 92.10 92.13 92.18 92.11 92.32 92.40 2E Metal Produced oz 444 759 440 298 451 895 459 379 457 645 460 819 403 858 291 683 151 694 97 371 75 316 Parameter Budget Units Units Units Actual Budget Parameter Parameter Budget 146 Figure 55: Stillwater Concentrator Actual and Forecast LoM Operational Throughput and Outputs Figure 56: Stillwater Concentrator Actual and Forecast LoM Operational Data - 5 10 15 20 25 30 35 0 200 400 600 800 1 000 1 200 1 400 1 600 FY 2 0 1 9 FY 2 0 2 0 FY 2 0 2 1 FY 2 0 2 2 FY 2 0 2 3 FY 2 0 2 4 FY 2 0 2 5 FY 2 0 2 6 FY 2 0 2 7 FY 2 0 2 8 FY 2 0 2 9 FY 2 0 3 0 FY 2 0 3 1 FY 2 0 3 2 FY 2 0 3 3 FY 2 0 3 4 FY 2 0 3 5 FY 2 0 3 6 FY 2 0 3 7 FY 2 0 3 8 FY 2 0 3 9 FY 2 0 4 0 FY 2 0 4 1 FY 2 0 4 2 FY 2 0 4 3 FY 2 0 4 4 FY 2 0 4 5 FY 2 0 4 6 FY 2 0 4 7 FY 2 0 4 8 FY 2 0 4 9 FY 2 0 5 0 FY 2 0 5 1 FY 2 0 5 2 FY 2 0 5 3 FY 2 0 5 4 FY 2 0 5 5 C o n c e n tr a te ( th o u sa n d t o n s) F e e d ( th o u sa n d t o n s) RoM Ore Feed Recycle Feed Concentrator Capacity Concentrate Produced 0 100 200 300 400 500 600 700 74 76 78 80 82 84 86 88 90 92 94 96 98 FY 2 0 1 9 FY 2 0 2 0 FY 2 0 2 1 FY 2 0 2 2 FY 2 0 2 3 FY 2 0 2 4 FY 2 0 2 5 FY 2 0 2 6 FY 2 0 2 7 FY 2 0 2 8 FY 2 0 2 9 FY 2 0 3 0 FY 2 0 3 1 FY 2 0 3 2 FY 2 0 3 3 FY 2 0 3 4 FY 2 0 3 5 FY 2 0 3 6 FY 2 0 3 7 FY 2 0 3 8 FY 2 0 3 9 FY 2 0 4 0 FY 2 0 4 1 FY 2 0 4 2 FY 2 0 4 3 FY 2 0 4 4 FY 2 0 4 5 FY 2 0 4 6 FY 2 0 4 7 FY 2 0 4 8 FY 2 0 4 9 FY 2 0 5 0 FY 2 0 5 1 FY 2 0 5 2 FY 2 0 5 3 FY 2 0 5 4 FY 2 0 5 5 2 E M e ta l P ro d u c e d ( k o z) 2 E R e c o v e ry ( % ) 2E Metal Produced 2E Recovery 147 16.2.1.5 Energy Requirements Power to the concentrator is fed from the West Substation as detailed in Section 17.1.3 and is delivered to the plant via incoming Line #2. The substation has sufficient capacity for the concentrator and the planned expansions. 16.2.1.6 Water Requirements The Stillwater Concentrator water balance is water-positive, and the concentrator receives return water from the Hertzler TSF, as well as treated water from underground. The Nye TSF is used as the excess water storage facility. East Boulder Concentrator 16.2.2.1 Plant Capacity The concentrator at East Boulder Mine was commissioned in 2001 as a 2 000-ton per operating day conventional crushing, milling and flotation plant producing a PGM-base metal sulphide concentrate suitable for downstream smelting and refining. The current capacity of the concentrator is approximately 2 500 tons per operating day following several process modifications and expansions. This capacity is equivalent to an estimated 838 000 tons per year at 92% operational utilisation which exceeds the planned steady state ore production levels of approximately 785 000 tons. The concentrator has historically processed approximately 650 000 tons per year of RoM ore feed from the Frog Pond East and West Sections of East Boulder Mine and achieved total 2E recoveries of approximately 91%. Operating the plant below capacity necessitated a ten-day or eleven-day fortnight operating basis, with plant switch-off every second weekend resulting in approximately 75% utilisation. Implementation of the Fill The Mill Project has resulted in a progressive increase in concentrator utilisation to the current (FY2021) average of 91%, with above 95% utilisation having been achieved in March, April and August 2021. The Qualified Person notes the plan to sustain the budgeted recovery to an average 91% for the LoM, which should be achievable through metallurgical input and optimisation, particularly given the change to continuous operations. The planned tonnage throughput of approximately 785 000 tons per annum for the LoM is deemed achievable considering that the annual targets are significantly below the 838 000 tons per year plant capacity at full operational utilisation. The upgraded concentrate handling facility which includes larger filter press and concentrate storage bin than were previously used and cater to side-tipping bulk trucks can handle the anticipated concentrate volumes. The side-tip trucks have the added advantage of also being usable for transporting slag or bricks from the Columbus Metallurgical Complex to the concentrators.
148 16.2.2.2 Manpower Requirements The plant staffing comprises three crews operating two 12-hour shifts of one Supervisor and three Concentrator Operators and one Heavy Equipment Operator per rotating crew as well as one Water Systems Operator. An additional three “roving” Concentrator Operators fill in for absences. Maintenance is currently staffed with six Mechanical Technicians, two Electrical Technicians, one Maintenance General Foreman, one Maintenance Planner and one Supervisor, all of whom currently work on a five-day per week basis. Major and routine planned maintenance is scheduled for shut-down intervals lasting 12 to 36 hours for every 28 days of plant run time, which has resulted in plant mechanical availability of more than 99%. These staffing levels are adequate for the current levels of operation. The increase in throughput necessitated the appointment of a fourth shift and the transition to continuous operations. Therefore, planned maintenance shut-downs have been initiated to ensure plant availability is maintained. 16.2.2.3 Process Description The simplified block flow for the East Boulder Concentrator is presented in Figure 57. The process comprises open circuit crushing followed by two stages of milling, with the sized product being delivered to the flotation circuit. Various stages of flotation including roughing, cleaning and scavenging in addition to a regrind circuit ensure that recovery is optimised and concentrate grades suitable for smelting are realised. Figure 57: East Boulder Concentrator Simplified Block Flow Diagram 149 16.2.2.4 Production Plan The recent history and budget operational parameters for the East Boulder Concentrator are presented together with the LoM budget data for the East Boulder Concentrator in Table 38, Figure 59. The FY2019, FY2020 and FY2021 data presented reflects the actual annual performance whilst the FY2022 to FY2061 data represents current budget targets. The current operational methods and capacities are adequate. Metallurgical efficiencies projected have also been sustainably obtained historically and are thus reasonable budget targets. Table 38: East Boulder Concentrator Actual and Forecast LoM Operational Throughput and Outputs The key variables reviewed for the LoM are presented in Figure 58 and Figure 59. FY2019 FY2020 FY2021 FY2022 FY2023 FY2024 FY2025 FY2026 FY2027 FY2028 FY2029 FY2030 FY2031 FY2032 FY2033 Total Feed tons 669 169 722 200 720 033 791 970 777 245 786 900 784 750 784 750 784 750 786 900 784 750 784 750 784 750 786 900 784 750 Concentrate Produced tons 15 945 17 733 17 859 19 472 19 110 19 347 19 294 19 294 19 294 19 347 19 294 19 294 19 294 19 347 19 294 2E Recovery % 90.80 90.85 90.60 91.00 91.00 91.00 91.00 91.00 91.00 91.00 91.00 91.00 91.00 91.00 91.00 2E Metal Produced oz 217 579 241 932 223 842 259 882 260 891 259 464 258 755 259 464 258 755 259 464 258 755 259 464 258 755 259 512 258 803 FY2034 FY2035 FY2036 FY2037 FY2038 FY2039 FY2040 FY2041 FY2042 FY2043 FY2044 FY2045 FY2046 FY2047 FY2048 Total Feed tons 784 750 784 750 786 900 784 750 784 750 784 750 786 900 784 750 784 750 784 750 786 900 784 750 784 750 784 750 786 900 Concentrate Produced tons 19 294 19 294 19 347 19 294 19 294 19 294 19 347 19 294 19 294 19 294 19 347 19 294 19 294 19 294 19 347 2E Recovery % 91.00 91.00 91.00 91.00 91.00 91.00 91.00 91.00 91.00 91.00 91.00 91.00 91.00 91.00 91.00 2E Metal Produced oz 259 512 258 803 252 983 252 122 258 471 268 357 253 537 253 465 254 159 253 465 254 696 253 465 254 159 253 465 254 696 FY2049 FY2050 FY2051 FY2052 FY2053 FY2054 FY2055 FY2056 FY2057 FY2058 FY2059 FY2060 FY2061 Total Feed tons 784 750 730 000 730 000 725 861 725 861 725 861 725 861 725 861 725 861 725 861 725 861 725 861 725 861 - - Concentrate Produced tons 19 294 17 948 17 948 17 846 17 846 17 846 17 846 17 846 17 846 17 846 17 846 17 846 17 846 - - 2E Recovery % 91.00 91.00 91.00 91.00 91.00 91.00 91.00 91.00 91.00 91.00 91.00 91.00 92.00 - - 2E Metal Produced oz 253 465 236 427 229 385 232 603 232 603 232 603 232 603 232 603 232 603 232 603 232 603 232 603 232 603 - - Parameter Units Budget Budget Budget Parameter Units Actual Parameter Units 150 Figure 58: East Boulder Concentrator Actual and Forecast LoM Operational Throughput and Outputs Figure 59: East Boulder Concentrator Actual and Forecast LoM Operational Data - 5 10 15 20 25 - 100 200 300 400 500 600 700 800 900 FY 2 0 1 9 FY 2 0 2 0 FY 2 0 2 1 FY 2 0 2 2 FY 2 0 2 3 FY 2 0 2 4 FY 2 0 2 5 FY 2 0 2 6 FY 2 0 2 7 FY 2 0 2 8 FY 2 0 2 9 FY 2 0 3 0 FY 2 0 3 1 FY 2 0 3 2 FY 2 0 3 3 FY 2 0 3 4 FY 2 0 3 5 FY 2 0 3 6 FY 2 0 3 7 FY 2 0 3 8 FY 2 0 3 9 FY 2 0 4 0 FY 2 0 4 1 FY 2 0 4 2 FY 2 0 4 3 FY 2 0 4 4 FY 2 0 4 5 FY 2 0 4 6 FY 2 0 4 7 FY 2 0 4 8 FY 2 0 4 9 FY 2 0 5 0 FY 2 0 5 1 FY 2 0 5 2 FY 2 0 5 3 FY 2 0 5 4 FY 2 0 5 5 FY 2 0 5 6 FY 2 0 5 7 FY 2 0 5 8 FY 2 0 5 9 FY 2 0 6 0 FY 2 0 6 1 C o n c e n tr a te P ro d u c e d ( th o u sa n d t o n s) F e e d ( th o u sa n d t o n s) Total Feed Concentrator Capacity Concentrate Produced 0 50 100 150 200 250 300 74 76 78 80 82 84 86 88 90 92 94 96 FY 2 0 1 9 FY 2 0 2 0 FY 2 0 2 1 FY 2 0 2 2 FY 2 0 2 3 FY 2 0 2 4 FY 2 0 2 5 FY 2 0 2 6 FY 2 0 2 7 FY 2 0 2 8 FY 2 0 2 9 FY 2 0 3 0 FY 2 0 3 1 FY 2 0 3 2 FY 2 0 3 3 FY 2 0 3 4 FY 2 0 3 5 FY 2 0 3 6 FY 2 0 3 7 FY 2 0 3 8 FY 2 0 3 9 FY 2 0 4 0 FY 2 0 4 1 FY 2 0 4 2 FY 2 0 4 3 FY 2 0 4 4 FY 2 0 4 5 FY 2 0 4 6 FY 2 0 4 7 FY 2 0 4 8 FY 2 0 4 9 FY 2 0 5 0 FY 2 0 5 1 FY 2 0 5 2 FY 2 0 5 3 FY 2 0 5 4 FY 2 0 5 5 FY 2 0 5 6 FY 2 0 5 7 FY 2 0 5 8 FY 2 0 5 9 FY 2 0 6 0 FY 2 0 6 1 2 E M e ta l P ro d u c e d ( k o z) 2 E R e c o v e ry ( % ) 2E Metal Produced 2E Recovery 151 16.2.2.5 Energy Requirements The concentrator at East Boulder Mine is fed with power from a dedicated substation which comprises a 15/20MVA transformer. Sufficient power is available for the mill operations. 16.2.2.6 Water Requirements The overall mine water balance is water positive, requiring disposal of treated water. The concentrator utilises a combination of TSF return water and treated underground water for processing purposes. 16.2.2.7 Process Materials Requirements As is the case for the Stillwater Concentrator, the process materials (reagents and steel balls) used in the East Boulder Concentrator are readily available and mostly sourced from credible suppliers located in the USA or North America. The Qualified Persons are satisfied that the measures in place in respect of the supply of process materials which should ensure security of supplies over the life of the operations. Concentrator Process Control Sampling The concentrators at Stillwater and East Boulder Mines carry out routine sampling at various stages of the process to produce the data required for the management of the processes and accounting for the metals processed. The samples are analysed at the Sibanye-Stillwater-owned and operated laboratory located at the Columbus Metallurgical Complex. Concentrator feed samples for Stillwater and East Boulder Mines are not taken at either concentrator due to the inclusion of flash flotation and gravity recovery processes within the milling circuit. This precludes representative sampling of the concentrator head feed stream and, as a result, concentrator metallurgical recoveries and plant head feed grades (which are the basis for Mineral Reserve grades reported) are back-calculated from feed mass, concentrate mass and grade, and tailings grade. The concentrate and tailings samples are taken at both concentrators using automated linear falling stream sample cutters. The samples are produced in duplicate using two stage rotary samplers on the concentrate thickener feed pipeline, resulting in a 24-hour composite sample, which is representative of the concentrator final product. This composite sample is not used for accounting purposes as the concentrate sample from the smelter is used for this purpose. Linear falling stream sample cutters also produce the primary tailings samples, which are reduced using two stage rotary tailings samplers at both plants to produce duplicate samples from the final float tails streams. This tailings material sampling process results in the production of a duplicate daily composite sample for analysis. The final tails material is then pumped to the sand plant in the case of the concentrator at East Boulder Mine, and the tailings dewatering section for the concentrator at Stillwater Mine. The laboratory analytical process followed for the concentrator samples resembles that employed for the geological samples described in Section 10 although the concentrate samples are processed in a separate line dedicated for the receiving, preparation and analysis of these high-grade samples. The
152 sampling equipment and the sampling regimes in place are adequate and suitable for the operations. The concentrate sample analyses are subsequently verified via the automated sampling process of the concentrate at the smelter and analysis at the laboratory. Smelting and Refining Background The Columbus Metallurgical Complex was commissioned in 1990 and focused on smelting concentrate from Stillwater Mine. Initially, a 30-ton concentrate per day smelting facility was installed, which was subsequently replaced with a 100-ton per day unit in 1999. Prior to 1990, concentrate from the concentrator at Stillwater Mine (the only concentrator at the time) was exported to Belgium for toll treatment and refining. The smelting operations have been expanded over the years, with the diversity of the operations at the complex also expanded to include base metal refining and PGM autocatalytic converter recycling operations. Currently, the smelter beneficiates the primary PGM concentrate from Stillwater and East Boulder Mines as well as PGM autocatalytic material sourced from third parties. There have been modest capacity upgrades of various units of the smelter and refinery which are part of the Blitz Project. Smelter 16.3.2.1 Capacity The smelter comprises two 150-ton per day primary smelting furnaces (Furnace #1 and Furnace #2), both of which can be configured to operate in a primary role or alternatively with Furnace #2 in a primary role and Furnace #1 in a slag cleaning role. PGM concentrate averaging 11% to 13% moisture is received from the concentrators in 30-ton side-tipping trucks. The following areas of the smelter are being or have been recently upgraded with a view to increasing tonnage throughput capacity in response to production increases at Stillwater and East Boulder Mines: • Concentrate Receiving and Drying: A completely new concentrate receiving facility was designed and constructed. This allows delivery via side-tip trucks with the concentrate offloaded and rehandled into the feeding system via a dedicated front-end loader. A new fluid bed dryer has also been installed with a nominal capacity of approximately 400 tons per day, which increased the concentrate drying capacity to accommodate the planned increases in concentrate production. Both concentrate handling and drying facilities were commissioned in early FY2021; • Smelter and Gas Cleaning: The hearth on Electric Furnace 2 was increased in size and the feeding system was upgraded. Both Electric Furnace 1 and Electric Furnace 2 now operate in primary smelting duty at an installed power of 7.5MW each, with a combined feed capacity of 300 ton per day of dried concentrate. The Electric Furnace 2 upgrades were completed during FY2018 and no further work is envisaged. The gas handling facility did not require any upgrades to accommodate the increased furnace capacity and has demonstrated adequate capacity since the completion of the Electric Furnace 2 upgrade; 153 • Granulation: The slag handling methodology is such that top blown rotary converter slag and furnace slag materials are treated separately. While the furnace slag is slow cooled and returned to the Stillwater or East Boulder Mine Concentrators for re-milling, the converter slag is granulated at the smelter. This granulation facility has been redesigned for upgrade. The top blown rotary converter matte dryer was installed during FY2021, but the electric furnace matte/top blown rotary converter slag dryer will be installed in early FY2022; • Top Blown Rotary Converters: Hatch recommended a third top blown rotary converter as part of its design and capacity increase review, but the existing two top blown rotary converters are planned to be upgraded to larger drums, which will mean larger charge capacity and longer blowing time. This will increase overall converting capacity by reducing converter downtimes. This project is due for implementation during FY2022. A further change to the top blown rotary converter operation will be implemented in FY2023 when the converter slag will be treated in its own slow cooling facility outside the building before being crushed and fed back to the furnaces as a high-grade revert product; and • Regeneration: In order to maintain the Columbus Metallurgical Complex’s permitted sulphur dioxide discharge level in the final atmospheric discharge gas, an additional sodium hydroxide regeneration train was installed. This unit modifies the scrubber liquor with the addition of further NaOH and subsequent addition of hydrated lime, which precipitates a gypsum product (CaSO4.2H2O), which is sold as an agricultural soil modifier and regenerates the NaOH for reuse in the scrubber circuits. The additional caustic regeneration train is a duplicate of the existing trains and is fully operational. 16.3.2.2 Process Description The simplified process flow block diagram for the smelter processes is presented in Figure 60. The concentrate bins delivered to the smelter are sampled, where after the concentrate is discharged via an elevator system into a fluidised bed dryer. Natural gas is available at the Columbus Metallurgical Complex site as a piped utility and, as such, is used wherever possible as a heating source. The dryer is thus natural gas fired and reduces the concentrate moisture to below 1%. Used automotive catalysts, which average 70oz 2E per ton, are combined with the new concentrate feed after the dryer. These materials are sampled and prepared separately. The treatment and processing of recycle materials is addressed in Section 22.1. High-temperature furnace fume and process gases from the electric furnace roof extraction system enter a primary bag house, whilst the lower temperature gas and particulates from the tapping, converting and granulation processes enter a secondary baghouse. The baghouses use high- performance Gore-Tex coated membrane bags to capture the particulates, which are recycled back to the furnace feed hoppers via a pneumatic conveying system. Matte produced from the arc furnaces is granulated and then charged into the top-blown rotary converter (TBRC), where the sulphur and iron components are oxidised. The slag from this process is recycled to the furnaces. The matte typically contains 350oz 2E per ton to 700oz 2E per ton, 28% to 30% Cu, 40% to 42% Ni, 20% to 22% S, 2% iron (Fe) and the balance comprising cobalt (Co), gold (Au), silver (Ag), Rh, tellurium (Te) and selenium (Se). 154 Figure 60: A Simplified Block Flow Diagram of the Smelter 16.3.2.3 Process Control Sampling All concentrate transfers to the smelter from the two concentrators are sampled using a pipe sampler on a grid pattern prior to offloading. A final composite sample per shipment with an ultimate sample mass of approximately 10lbs is then transported to the in-house laboratory. This sample provides the definitive analysis for the concentrate from the concentrators, which is used in the metallurgical accounting process. Converter matte, once granulated, is the smelter final product and is sampled at the smelter by a falling stream sampler at the granulator. A primary sample is taken, which is reduced to approximately 2lb via a twelve-point rotary splitter before being manually delivered as a duplicate sample to the in-house laboratory. This sample provides the definitive analysis for the convertor matte from the smelter, which is used in the metallurgical accounting process. The laboratory analysis process flow for smelter samples resembles that for the geological samples described in Section 10, although the converter matte and concentrate samples are processed in a separate line dedicated for the receiving, preparation and analysis of high-grade samples. Other samples produced by the smelter for analysis at the analytical laboratory, which are utilised for internal accounting purposes, are as follows: • Furnace slag: spoon samples are taken during the tapping process and composited daily; • Converter slag: converter slag is grab sampled from each bin produced for recycle back to the furnaces, and composited on a daily and weekly basis; • Furnace matte: furnace matte is grab sampled from each bin produced and composited on a daily and weekly basis; and 155 • Gypsum product: gypsum product is pipe-sampled from each weekly composite sample container bin resulting in a bulk sample, which is dried and incrementally split for analysis of the final aliquot. The sampling equipment and the sampling regimes in place at the smelter are adequate and suitable for the operations. 16.3.2.4 Production Plan The recent history and budget operational parameters for the smelter plant have been reviewed and the key variables are presented in Table 39, Figure 61 and Figure 62. The FY2019 and FY2021 data presented reflects the actual annual performance whilst the FY2022 to FY2061 data represents the current budget targets. Metallurgical efficiencies projected have also been sustainably obtained historically and are thus reasonable budget targets. The increases in smelter operational duty planned are visible whilst the other key variables such as smelter first pass recovery and recycle tons treated remain at levels previously achieved. Table 39: Smelter Historical and Budget Operational Data FY2019 FY2020 FY2021 FY2022 FY2023 FY2024 FY2025 FY2026 FY2027 FY2028 FY2029 FY2030 FY2031 FY2032 FY2033 Smelter Concentrate Feed tons 35 165 39 548 40 393 44 674 47 448 50 173 49 073 51 343 52 431 52 321 52 405 50 262 52 390 52 426 52 303 Smelter Recycle Feed tons 10 834 10 220 9 561 10 766 10 955 12 361 12 137 12 426 11 409 11 361 11 202 10 923 11 187 10 040 9 517 Converter Matte Produced tons 2 150 2 335 2 031 2 433 2 512 2 814 2 763 2 829 2 597 2 586 2 550 2 487 2 547 2 286 2 167 Smelter 1st Pass Recovery % 96.90 97.46 97.37 97.09 97.14 96.91 96.89 96.91 96.96 97.04 97.12 97.11 97.13 97.20 97.23 Total 2E Recovered oz 1 395 533 1 421 217 1 257 205 1 481 640 1 545 481 1 726 398 1 711 249 1 765 469 1 705 131 1 624 792 1 550 650 1 493 521 1 533 629 1 456 075 1 417 197 FY2034 FY2035 FY2036 FY2037 FY2038 FY2039 FY2040 FY2041 FY2042 FY2043 FY2044 FY2045 FY2046 FY2047 FY2048 Smelter Concentrate Feed tons 52 479 52 445 52 556 52 531 52 535 52 557 52 628 52 573 52 557 52 463 52 320 52 306 52 249 52 286 52 361 Smelter Recycle Feed tons 9 608 9 666 9 283 9 261 9 315 9 042 8 779 8 753 8 783 8 572 9 859 8 315 11 062 10 868 10 576 Converter Matte Produced tons 2 187 2 201 2 113 2 108 2 121 2 059 1 999 1 993 2 000 1 951 2 245 1 893 2 519 2 474 2 408 Smelter 1st Pass Recovery % 97.24 97.26 97.27 97.23 97.23 97.27 97.33 97.33 97.31 97.34 97.24 97.35 97.17 97.17 97.17 Total 2E Recovered oz 1 415 456 1 400 899 1 389 562 1 412 391 1 413 408 1 377 127 1 337 337 1 330 176 1 344 132 1 322 578 1 418 681 1 304 638 1 500 522 1 497 251 1 484 712 FY2049 FY2050 FY2051 FY2052 FY2053 FY2054 FY2055 FY2056 FY2057 FY2058 FY2059 FY2060 FY2061 Smelter Concentrate Feed tons 52 290 50 952 48 884 41 578 31 467 27 437 26 102 23 569 20 329 20 329 20 329 20 329 20 329 - - Smelter Recycle Feed tons 10 577 9 976 9 304 8 530 6 074 5 694 5 543 5 463 4 917 4 917 4 917 4 917 4 917 - - Converter Matte Produced tons 2 408 2 271 2 118 1 942 1 383 1 296 1 262 1 244 1 119 1 119 1 119 1 119 1 119 - - Smelter 1st Pass Recovery % 97.18 97.19 97.26 97.19 97.24 97.20 97.20 97.11 97.11 97.11 97.11 97.11 97.11 - - Total 2E Recovered oz 1 481 858 1 424 214 1 311 488 1 171 762 852 897 770 757 737 717 710 081 616 644 616 644 616 644 616 644 616 644 - - Parameter Units Budget Budget Parameter Units Actual Budget Parameter Units
156 Figure 61: Smelter Actual and Forecast LoM Operational Throughput Figure 62: Smelter LoM Operational Performance, Actual and Forecast 0 500 1 000 1 500 2 000 2 500 3 000 0 5 000 10 000 15 000 20 000 25 000 30 000 35 000 40 000 45 000 50 000 55 000 60 000 65 000 70 000 FY 2 0 1 9 FY 2 0 2 0 FY 2 0 2 1 FY 2 0 2 2 FY 2 0 2 3 FY 2 0 2 4 FY 2 0 2 5 FY 2 0 2 6 FY 2 0 2 7 FY 2 0 2 8 FY 2 0 2 9 FY 2 0 3 0 FY 2 0 3 1 FY 2 0 3 2 FY 2 0 3 3 FY 2 0 3 4 FY 2 0 3 5 FY 2 0 3 6 FY 2 0 3 7 FY 2 0 3 8 FY 2 0 3 9 FY 2 0 4 0 FY 2 0 4 1 FY 2 0 4 2 FY 2 0 4 3 FY 2 0 4 4 FY 2 0 4 5 FY 2 0 4 6 FY 2 0 4 7 FY 2 0 4 8 FY 2 0 4 9 FY 2 0 5 0 FY 2 0 5 1 FY 2 0 5 2 FY 2 0 5 3 FY 2 0 5 4 FY 2 0 5 5 FY 2 0 5 6 FY 2 0 5 7 FY 2 0 5 8 FY 2 0 5 9 FY 2 0 6 0 FY 2 0 6 1 M a tt e P ro d u c e d ( to n s) F e e d ( to n s) Smelter Concentrate Feed Smelter Recycle Feed Converter Matte Produced 0 200 400 600 800 1 000 1 200 1 400 1 600 1 800 78 80 82 84 86 88 90 92 94 96 98 100 FY 2 0 1 9 FY 2 0 2 0 FY 2 0 2 1 FY 2 0 2 2 FY 2 0 2 3 FY 2 0 2 4 FY 2 0 2 5 FY 2 0 2 6 FY 2 0 2 7 FY 2 0 2 8 FY 2 0 2 9 FY 2 0 3 0 FY 2 0 3 1 FY 2 0 3 2 FY 2 0 3 3 FY 2 0 3 4 FY 2 0 3 5 FY 2 0 3 6 FY 2 0 3 7 FY 2 0 3 8 FY 2 0 3 9 FY 2 0 4 0 FY 2 0 4 1 FY 2 0 4 2 FY 2 0 4 3 FY 2 0 4 4 FY 2 0 4 5 FY 2 0 4 6 FY 2 0 4 7 FY 2 0 4 8 FY 2 0 4 9 FY 2 0 5 0 FY 2 0 5 1 FY 2 0 5 2 FY 2 0 5 3 FY 2 0 5 4 FY 2 0 5 5 FY 2 0 5 6 FY 2 0 5 7 FY 2 0 5 8 FY 2 0 5 9 FY 2 0 6 0 FY 2 0 6 1 2 E R e c o v e re d ( k o z) 2 E R e c o v e ry ( % ) New Feed 2E Recovered Recycle Feed 2E Recovered Smelter 1st Pass Recovery 157 16.3.2.5 Manpower Requirements The budgeted total smelter manpower complement is 105 consisting of 44 hourly and 19 salaried employees in operations and 28 hourly and 14 salaried employees in maintenance. 16.3.2.6 Energy Requirements Power is supplied to the Columbus Metallurgical Complex via a dedicated switching station containing two transformers. The power supply is adequate for both the smelting and base metal refining operations. 16.3.2.7 Water Requirements The entire Columbus Metallurgical Complex is water neutral, with sufficient recycle and storage facilities included. The water supply is adequate for both the smelting and base metal refining operations. 16.3.2.8 Flux and Other Requirements The process materials (e.g., flux) used in the smelting operations are readily available. Most sources are domestic in nature and the overseas sources have been studied intensely to evaluate secondary and tertiary sources in case of supply chain interruption from the primary source. The Qualified Persons are satisfied with security of supplies in respect of process materials for the smelting operations over the life of operations. Base Metal Refinery 16.3.3.1 Capacity The base metals refinery facility was installed in 1996 at a nameplate capacity of 660lbs per hour but has a current capacity of more than 1 200lb per hour of granulated matte due to some process expansions – primarily a result of process optimisation and improvement. The base metals refinery currently operates on two 12-hour shifts continuously from Monday morning to Thursday afternoon (equivalent to 80 hours per week or a utilisation of 47.6%). The copper electrowinning circuit at the facility, which operates continuously, was expanded in FY2021 by adding six cells to eliminate a bottleneck that occurred historically in the base metal refinery process. The expanded processing capacity can produce 750 tons per year of copper, with spare capacity remaining. The Qualified Person is also of the view that, with the current matte capacity exceeding 1 200lb per hour and the expanded copper electrowinning circuit, the forecast matte volumes and nickel processing capacity can be accommodated through the existing operational schedule, with occasional overtime to cover any variance. 16.3.3.2 Process Description The granulated converter matte product is weighed upon receipt at the base metal refinery facility. The matte is milled and leached with sulphuric acid at atmospheric conditions to remove nickel as a 158 sulphate crystal product. The remaining solids from the nickel leach are then leached with sulphuric acid under pressurized conditions to dissolve selenium (Se), tellurium (Te) and copper. The former two metals are cemented out of solution, leaving the copper solution for electrowinning. The solids remaining after Se/Te/Cu dissolution forms the PGM filter cake, which is washed, filtered and dried. The simplified process flow block diagram for the Base Metal Refinery processes is presented in Figure 63. The final product (filter cake) is despatched to Johnson Matthey Company (Johnson Matthey) for further separation and refining. Figure 63: A Simplified Block Flow Diagram of the Base Metal Refinery 159 16.3.3.3 Process Control Sampling The converter matte bins received from the smelter at the base metal refinery are weighed and the mass becomes the final value used in the metal accounting system. The analysis used in the accounting system originates from the final smelter sample. Base metal refinery products are all sampled within the production process and the products are analysed for quality control purposes only as follows: • NiSO4 crystals: A primary sample is taken from the bagging process via a rotary splitter, which is reduced further for final analysis; • Copper cathode: This is sampled by drilling of the cathode plate, digested and analysed by ICP spectrometry for the copper turnings produced, and the analysis is used as the dispatch analysis for the cathode product; and • PGM filter cake: This is the final base metal refinery product shipped to Johnson Matthey for further refining. This material is sampled at the final product dryer by a rotary splitter and is then sub- sampled. Duplicate samples are produced, and the analytical results of these samples become the invoice analyses for the shipments. The invoiced analysis is checked by Johnson Matthey on receipt, in addition to which there is an umpire process, which is followed for variances greater than those allowed in the contract. The in-house laboratory reports quarterly on the correlations achieved between analyses from Johnson Matthey, in- house and umpire laboratories (where required) on a per element basis. The base metal refinery sample analysis process also resembles that for the geological samples described in Section 10 although the filter cake, converter matte and concentrate samples are processed in a separate line dedicated for the receiving, preparation and analysis of high-grade samples. The sampling equipment and the sampling regimes in place at the base metal refinery are adequate and suitable for the operations. 16.3.3.4 Manpower Requirements The total base metal refinery manpower complement is 37 consisting of 18 hourly and 8 salaried employees in operations and 7 hourly and 4 salaried employees in maintenance. 16.3.3.5 Process Materials Requirements The process materials (reagents) used in the base metal refinery are also readily available and sourced from credible domestic suppliers. The Qualified Persons are satisfied that the measures in place in respect of the supply of process materials which should ensure security of supplies over the life of the operations. 16.3.3.6 Production Plan The recent history and budget operational parameters for the Base Metal Refinery have been reviewed and the key variables are presented in Table 40, Figure 64 and Figure 65. The FY2019, FY2020, and FY2021 data presented reflects the actual annual performance whilst the FY2022 to FY2061 data presents the
160 current LoM budget targets. The Qualified Person is of the view that the current operational methods and capacities are adequate. Metallurgical recoveries projected have also been sustainably obtained historically and are reasonable budget targets. Table 40: Base Metal Refinery Historical and Forecast LoM Operational Data Figure 64: Base Metal Refinery Actual and Forecast LoM Operational Throughput and Base Metals Recovered FY2019 FY2020 FY2021 FY2022 FY2023 FY2024 FY2025 FY2026 FY2027 FY2028 FY2029 FY2030 FY2031 FY2032 FY2033 BMR Matte Feed tons 2 150 2 335 2 043 2 433 2 512 2 814 2 763 2 829 2 597 2 586 2 550 2 487 2 547 2 286 2 167 Cu Produced tons 600 574 551 666 681 775 764 778 701 691 675 661 673 619 581 Ni Produced tons 936 876 900 1 048 1 087 1 206 1 181 1 213 1 128 1 131 1 121 1 091 1 121 990 945 Total 2E Recovered oz 1 396 523 1 424 207 1 255 404 1 471 973 1 536 573 1 722 613 1 707 494 1 761 598 1 701 405 1 621 255 1 547 290 1 490 284 1 530 308 1 452 933 1 414 144 PGM Recovery % 99.80 99.80 99.80 99.80 99.80 99.80 99.80 99.80 99.80 99.80 99.80 99.80 99.80 99.80 99.80 FY2034 FY2035 FY2036 FY2037 FY2038 FY2039 FY2040 FY2041 FY2042 FY2043 FY2044 FY2045 FY2046 FY2047 FY2048 BMR Matte Feed tons 2 187 2 201 2 113 2 108 2 121 2 059 1 999 1 993 2 000 1 951 2 245 1 893 2 519 2 474 2 408 Cu Produced tons 586 589 564 564 567 544 527 525 527 504 605 471 689 675 653 Ni Produced tons 954 961 925 921 927 906 880 879 882 872 976 863 1 084 1 067 1 042 Total 2E Recovered oz 1 412 408 1 397 886 1 386 574 1 409 349 1 410 364 1 374 168 1 334 470 1 327 326 1 341 249 1 319 745 1 415 626 1 301 845 1 497 278 1 494 014 1 481 505 PGM Recovery % 99.80 99.80 99.80 99.80 99.80 99.80 99.80 99.80 99.80 99.80 99.80 99.80 99.80 99.80 99.80 FY2049 FY2050 FY2051 FY2052 FY2053 FY2054 FY2055 FY2056 FY2057 FY2058 FY2059 FY2060 FY2061 BMR Matte Feed tons 2 408 2 271 2 118 1 942 1 383 1 296 1 262 1 244 1 119 1 119 1 119 1 119 1 119 - - Cu Produced tons 653 611 569 541 385 373 366 371 340 340 340 340 340 - - Ni Produced tons 1 042 988 923 826 588 539 521 503 446 446 446 446 446 - - Total 2E Recovered oz 1 478 657 1 421 139 1 308 668 1 169 232 851 061 769 094 736 125 708 542 615 308 615 308 615 308 615 308 615 308 - - PGM Recovery % 99.80 99.80 99.80 99.80 99.80 99.80 99.80 99.80 99.80 99.80 99.80 99.80 99.80 - - Parameter Units Budget Parameter Units Actual Budget Parameter Units Budget 0 100 200 300 400 500 600 700 800 900 1 000 1 100 1 200 1 300 0 200 400 600 800 1 000 1 200 1 400 1 600 1 800 2 000 2 200 2 400 2 600 2 800 3 000 FY 2 0 1 9 FY 2 0 2 0 FY 2 0 2 1 FY 2 0 2 2 FY 2 0 2 3 FY 2 0 2 4 FY 2 0 2 5 FY 2 0 2 6 FY 2 0 2 7 FY 2 0 2 8 FY 2 0 2 9 FY 2 0 3 0 FY 2 0 3 1 FY 2 0 3 2 FY 2 0 3 3 FY 2 0 3 4 FY 2 0 3 5 FY 2 0 3 6 FY 2 0 3 7 FY 2 0 3 8 FY 2 0 3 9 FY 2 0 4 0 FY 2 0 4 1 FY 2 0 4 2 FY 2 0 4 3 FY 2 0 4 4 FY 2 0 4 5 FY 2 0 4 6 FY 2 0 4 7 FY 2 0 4 8 FY 2 0 4 9 FY 2 0 5 0 FY 2 0 5 1 FY 2 0 5 2 FY 2 0 5 3 FY 2 0 5 4 FY 2 0 5 5 FY 2 0 5 6 FY 2 0 5 7 FY 2 0 5 8 FY 2 0 5 9 FY 2 0 6 0 FY 2 0 6 1 M e ta l P ro d u c e d ( to n s) B M R M a tt e F e e d ( to n s) BMR Matte Feed Cu Produced Ni Produced 161 Figure 65: Base Metal Refinery Actual and Forecast LoM Operational Performance PGM Prill Splits Sibanye-Stillwater measures and reports metal prill splits as a ratio of palladium to platinum in the various intermediate products from the individual operations. The current ratios based on data for the FY2021 period have been reviewed by the Qualified Person. The Pd and Pt prill split percentages, based on the Pd:Pt ratio in concentrate resulting from the processing of ore from Stillwater and Easter Boulder Mines, are presented in Table 41. Table 41: Summary of Pt and Pd Prill Split Data Mine Pd: Pt Ratio Prill Split FY2021 Pt Pd Stillwater Mine 3.51:1 22.17% 77.83% East Boulder Mine 3.60:1 21.73% 78.27% Processing Logistics Concentrate from both the Stillwater and East Boulder Concentrators, with moisture content of 11% to 13%, is trucked via side-tipper bulk trucks to the smelter. Travel time for the concentrate truck from East Boulder Mine to the smelter by road is approximately two to three hours but the travel time for the concentrate truck from Stillwater Mine to the smelter is approximately one and a half hours. Following tube sampling for moisture and initial assays, the material is introduced into a fluidised bed, natural gas dryer that reduces moisture to less than 1%. The dried concentrate is conveyed to a feed storage bin and sampled in duplicate. 0 200 400 600 800 1 000 1 200 1 400 1 600 1 800 2 000 90 91 92 93 94 95 96 97 98 99 100 FY 2 0 1 9 FY 2 0 2 0 FY 2 0 2 1 FY 2 0 2 2 FY 2 0 2 3 FY 2 0 2 4 FY 2 0 2 5 FY 2 0 2 6 FY 2 0 2 7 FY 2 0 2 8 FY 2 0 2 9 FY 2 0 3 0 FY 2 0 3 1 FY 2 0 3 2 FY 2 0 3 3 FY 2 0 3 4 FY 2 0 3 5 FY 2 0 3 6 FY 2 0 3 7 FY 2 0 3 8 FY 2 0 3 9 FY 2 0 4 0 FY 2 0 4 1 FY 2 0 4 2 FY 2 0 4 3 FY 2 0 4 4 FY 2 0 4 5 FY 2 0 4 6 FY 2 0 4 7 FY 2 0 4 8 FY 2 0 4 9 FY 2 0 5 0 FY 2 0 5 1 FY 2 0 5 2 FY 2 0 5 3 FY 2 0 5 4 FY 2 0 5 5 FY 2 0 5 6 FY 2 0 5 7 FY 2 0 5 8 FY 2 0 5 9 FY 2 0 6 0 FY 2 0 6 1 2 E R e c o v e re d ( k o z) 2 E R e c o v e ry ( % ) Total 2E Recovered PGM Recovery 162 Recycled automotive catalysts and other PGM-bearing materials, averaging 70oz 2E per ton, constitute a separate source of smelter feed. This is delivered to the smelter by clients in 3ft cube bags and boxes. This material is pulverised, sorted and sampled in the same manner prior to smelting to ensure client custom metal is accounted separately. All slag from the smelter as well as furnace and Top Blown Rotary Converter used lining bricks is sampled to quantify residual precious metals and is returned to both the Stillwater and East Boulder Concentrators. This is carried out via the return haul for the side-tipper trucks for re-milling to ensure residual metals are returned to the value stream. This is also accounted for in terms of the concentrator recovery performance measurement. 163 INFRASTRUCTURE Stillwater Mine Complex Concentrator Infrastructure The processing plant infrastructure at Stillwater Mine was built in 1987 and is in a good operational condition. Historical budgets have provided for adequate sustaining and project capital for maintenance and upgrades of plant infrastructure to ensure sustained performance at the required capacities. The planned maintenance of the Stillwater Concentrator follows the JD Edwards Maintenance Control system. Power supply to the concentrator plant is described in Section 17.1.3. As the Stillwater Concentrator is being upgraded to accommodate the increased capacity resulting from the Blitz expansion (Stillwater East Section), the power supply has also been upgraded accordingly. The concentrate handling thickener building and concentrate handling loadout building were completed and commissioned in FY2021. Several additional buildings are planned as part of the Concentrator Expansion to be completed in F2022 and these include the following: • Hertzler Overflow (O/F) tank and pump building; • Hertzler Motor Control Centre (MCC) expansion building; • 5150 process water expansion building; • Ore handling building; and • Grinding building. Tailings Storage Facilities The TSFs for Stillwater Mine are at the mature stage. Stillwater Mine has moved the production deposition from the original Nye TSF to the Hertzler TSF. The Hertzler TSF is permitted to Stage 3 (equivalent to a height of 5 030ftmamsl), after which additional permitting will be required following a revised design. The current plan is to increase the capacity of the Hertzler TSF with new, additional tailings storage cells 4 and 5, to accommodate the increased production rate arising following additional material from the Stillwater East Section. The TSF is inspected by independent consultants on an annual basis, with Knight- Piésold being the defined Engineer-of-Record. The TSFs at the Stillwater Mine comprises two slimes impoundments, namely the Nye TSF (no longer in full- time use) and the Hertzler TSF (current primary storage). The Nye TSF was used from the start of the mine until 2002, when the Hertzler TSF was commissioned, and it is currently undergoing capping for closure. The Hertzler TSF is currently permitted to an elevation of 5 030ft including freeboard and supernatant pond, which is the maximum extent of the current Stage 3 embankment raise. Concentrator tailings are sampled and pumped to a paste plant alongside the Nye TSF located to the southwest of the concentrator. The paste plant, which is used on a limited basis, operates as a staging point for whole tailings slurry. The tailings may be routed from the paste plant either to the 5150 Level
164 underground sand plant or to the Hertzler Pump House, from where it can be routed to either of the other sand plants or the Hertzler TSF. Tailings can also be routed to the Nye TSF from the concentrator, the paste plant or the pump house, if required. Whole tailings material is classified at the underground sand plants into coarse sand and slimes fractions, the sand remains underground and is pumped into stopes for backfilling purposes, whilst the slimes fraction is pumped back to the pump house. The slime is then pumped via two eight-inch pipelines to the Hertzler TSF for deposition. Deposition on the Hertzler TSF is via periodic rotational discharge of tailings slurry around the perimeter of the facility using a group of spigots. Once a localised tailings beach has formed, deposition is transferred to another group of spigots at a different location. Water reclamation is achieved via two inclined reclaim pumps located at the south end of the TSF, which return process water to the concentrator. The adjacent Land Application and Disposal (LAD) pond to the west of the Hertzler Tailings Storage Facility is used to manage treated mine water volumes. The TSF is geomembrane lined, and the liner is routinely inspected by the Engineer of Record, where possible. Basin underdrain and seepage measurement is performed and monitored via vibrating wire piezometers, whilst embankment crest-mounted survey monuments are used to measure slope slippage or movement. Additional inclinometers are installed around the base of the impoundment to monitor deeper ground movement and displacement. The basin underdrain pore pressures are monitored on a weekly basis via the piezometers, and these respond quickly to changes in the basin underdrain pumping rate. This results in changes in the tailings mass consolidation and hence maximises storage availability and assists in long-term closure planning. The concentrator performs weekly, monthly and quarterly TSF inspections and monitoring per its standard procedures, which are reviewed as part of the annual independent inspection of the TSF performed by Knight-Piésold of Canada. The inspections and monitoring are required by the 2015 Montana Metal Mine Reclamation Act (MCA). The most recent inspection was performed in October 2021, with surveillance data collected during the January to September 2021 period, and this raised no material issues. The Nye TSF, located immediately to the south of the mining and processing complex, was decommissioned as the primary storage facility in 2001 but is used for emergency tailings storage and water management purposes. Supernatant water is recycled to the concentrator as process water via an inclined retractable pump at the north end of the facility. Survey beacons are in place and are routinely measured for slope stability and slippage. The most recent inspection of the TSF by Knight- Piésold raised no material findings. Knight-Piésold has been retained to develop a closure and rehabilitation plan for the Nye TSF. Capping of the Nye TSF commenced in late FY2018 and is expected to be completed by FY2023. Stage 3 of the Hertzler TSF was completed in 2015 and filling of Stage 3 is currently underway. As part of the annual inspection of the Hertzler TSF, Knight-Piésold calculates a projected fill rate of the current and 165 planned TSF capacity as an elevation above mean sea level by year. Knight-Piésold's latest TSF filling calculations contained in the 2021 Annual Inspection Report estimates the Stage 3 limit of 5 030ftmsl to be reached (based on pond elevation) by August 2028 (Figure 66), at the envisaged RoM ore production rates. The Qualified Person is satisfied with Knight-Piésold's estimate of the Stage 3 capacity of Stage 3. Figure 66: Hertzler TSF Knight-Piésold Calculated Elevation Profile Stage 3 is currently the maximum permitted height of the Hertzler TSF and, as a result, operation of the TSF beyond this stage will require the design and approval of a Stage 4. A Plan of Operations Amendment for the Stage 4 and Stage 5 TSF expansions has been prepared and is planned for submission for agency approval in early (Q1) FY2022. The Stage 4 lift involves a capital expenditure amount of $47 million for design and construction, which has been budgeted for expenditure from FY2025 onwards as discussed in Section 20.2.2.4. The Qualified Person deems the quantum of the capital budget to be sufficient for the implementation of the Stage 4 expansion. Sibanye-Stillwater has indicated to the Qualified Person that there are no apparent impediments anticipated that will prevent the approval of the Stage 4 expansion. However, if the approval is declined and a new TSF is required, a timeframe of approximately five to seven years 166 for environmental permitting processes and two years for construction would be required. In addition, a higher capital budget provision than the current provision may be required. Power Stillwater Mine receives power from the North West Energy grid via three 161kV feed sources as follows: • 100kV line via the Columbus Auto-substation (located north of Columbus and running west to east); • 100kV from Billings via the Bridger Auto-substation; and • 100kV from the Mystic Lake Hydroelectric Power Plant. These powerlines feed the mine from the Chrome Junction Substation located west of Roscoe. The powerline from Chrome Junction to Stillwater Mine is a radial feed at 100kV and feeds three small substations belonging to Beartooth Electric. One of these substations feeds the Hertzler TSF. The mine site has two main substations, namely the West Substation and East Substation, both connected to North West Energy’s 100kV line. The West Substation is owned and maintained by North West Energy and feeds most of the existing mine site including the concentrator. The East Substation is owned and maintained by Stillwater Mine and was installed as part of the Blitz Project to power the Stillwater East Section. The actual power demand loads for Stillwater Mine are as follows: • West Substation: 19.5MW at 0.92 Power Factor, with current load capacity of approximately 109% without fans and 82% with fans; • East Substation: 3.5MW at 0.88 Power Factor, with current load capacity approximately 40% without fans and 32% with fans; and • Monthly maximum peak for the site: 23MW. To meet the Stillwater Mine production ramp up power requirements, the peak demand for the entire site increased to approximately 32MW in FY2021 and to remain constant thereafter. Accordingly, the maximum demand agreement with North West Energy was increased to 32MW. This incremental load was placed on the East Substation while the West Substation remains on approximately 19.5MW. Power into Stillwater Mine is reticulated from the West Substation through two incoming lines (Incomer Line #1 and Incomer Line #2). Incoming line #1 distributes to the following: • Upper West Feeder; • 5000 West Portal Feeder; • West Compressor/Surface Feeder; • Vertical Mill; and • Skip Hoist and Shaft feeder. Incoming Line #2 feeds to the following: • Main Shaft Feeder A for mining operations; • Main Shaft Feeder B for mining operations; • Man hoist; • Concentrator and ball mill; 167 • Semi-autogenous Grinding (SAG) mill; and • Auxiliary services including workshops and hoist room. Stillwater Mine has a 750kVA emergency generator to power the cage hoist and provide emergency power for the phones and other small critical loads. All underground transformers are dry-cooled, eliminating the risk of oil leakage and/or fire. In addition, these transformers are skid mounted, installed in concreted cubbies, well- demarcated and supplied with lighting. Stillwater Mine has a detailed inventory of all underground switchgear, controller and transformers managed through the JD Edwards Management System. Bulk Water 17.1.4.1 Water Supply The bulk water supply for the Stillwater Mine is a mix of fresh make-up water from supply wells and recycled mine water. The overall water balance is positive meaning that water disposal is required. Treatment and disposal of surplus water are discussed in Section 17.1.4.2. The onsite water supply wells provide potable water for the mine, make-up water for reagent mixing, and cooling water to some systems (e.g., lube system cooling). Onsite, the water is reticulated to various sites through a network of pipelines (distribution system). The two existing wells and associated distribution system is adequate for the Stillwater Mine ramp up production requirements. Water consumption from the wells is approximately 24gal per minute and will increase to 36gal per minute at steady state production levels. The Qualified Persons recognise that net positive water balance at the site is adequate for ongoing operations. 17.1.4.2 Water Treatment The water treatment system at Stillwater Mine treats and disposes impacted water from the underground mining operations. Impacted mine water is first clarified before a portion is reused as mine service water while the remaining water continues to the biological treatment process to remove nitrates and is then disposed of by land application or infiltration. The current system was designed to treat the approximate 1 200gal per minute inflow from the Stillwater West Section. Results of groundwater studies in FY2021 suggested water inflows into the Stillwater East Section of approximately 3 000gal per minute; this has since been derated to 1 600gal per minute informed by results of subsequent work completed in FY2021. The design flow for the new treatment and disposal system is 3 000gal per minute. The pipeline project from Pond 3 to Vault 3 to increase the capacity from 1 800gal per minute to 2 300gal per minute was completed in FY2021. In addition, clarifier upgrades were completed in FY2021 to increase capacity to 2 500gal per minute for each clarifier resulting in a total clarifier capacity of 5 000gal per minute.
168 17.1.4.3 Septic System The sanitary utilities at the Stillwater Mine consist of a septic system that includes a solids tank, an Advantex treatment system and a leach field. The system is operated primarily as a treatment and disposal system with the leach field providing secondary or back-up disposal. The treated effluent is sent to the Hertzler Land Application Disposal system for disposal. The capacity of the septic system of 18 000gal per day is adequate for the steady-state requirements for Stillwater Mine. Roads Stillwater Mine is located approximately 30 miles southwest of Absarokee and 4 miles south-southwest of Nye. It is accessed from Absarokee by the mainly unpaved County Road 420, which passes the Hertzler Ranch TSF or via the paved State Highway 78 and State Highway 419 and Nye Road. The road network on the Stillwater Mine site consists of unpaved roads, which are primarily used for the transport of logistics and stores for the functioning of the mine and for transport of personnel for access to the infrastructure positioned around the mine site. Equipment Maintenance Stillwater Mine has three workshops on surface, which are the following: • Surface Locomotive Workshop: This has a single bay service and mechanical repair facility for all rolling stock (locomotives and ore cars) operating on the 5 000 Level West. This workshop is primarily for work on wheels and engines; • East Side Workshop: This has multiple bay service and mechanical repairs facilities mainly serving the Stillwater East Section development equipment and any maintenance and repairs associated with the Tunnel Boring Machine; and • Surface Truck Workshop: This has multiple bay service and mechanical repair facilities for surface trucks with full machining, welding and Diesel Particulate Matter service and testing facilities. In addition, Stillwater Mine has the following underground workshops: • 6100W Level Workshop: This has multiple bay services and mechanical repair shop; • 5000W Level Workshop: This is dedicated to the trackless equipment, which is serviced in the mine. It has a single bay service facility and is available for light mechanical repairs, servicing and electrical repairs on mobile equipment. All the rail equipment on this level is serviced and repaired on surface; • 3500W Level Kiruna Workshop: This is a single bay service and mechanical repair workshop facility, which was designed specifically for the maintenance of the three Kiruna trucks and for maintenance of the AD30 Cat Trucks. The Kiruna trucks have been decommissioned; • 3500W Level Locomotive Workshop: The 3 500 Level is primarily an ore and waste rock tramming level. Therefore, the workshop is a two-bay service and repair facility for rolling stock; • 3800W Level Workshop: This is a two-bay service and light mechanical repairs shop for all production equipment on the level. Much of the equipment is not suitable for extensive travel, such as drill rigs, bolters and CMAC drills and should be maintained in the workings (point of use); • 3800E Level Workshop. This is a multiple bay service and mechanical repair shop subject to the same requirements at the 3800W Level Workshop; 169 • 2000W Level Workshop: This is the workshop on the lowest level, which caters for mechanical, electrical and general repair and services in multiple bays. All the underground workshops are well-equipped with good lighting, clean concrete floor areas for maintenance and wash bays to ensure quality inspections, and are stocked with the appropriate tools and lifting equipment. Some of the workshops also provide for an administrative office underground to ensure that the planned maintenance system is updated timeously. A well-developed maintenance programme based on the JD Edwards Planned Maintenance system is in place and this includes daily, weekly and monthly scheduled maintenance. Major rebuilds of equipment take place on site or are sent to offsite Original Equipment Manufacturer (OEM) repair shops. In addition, the Sibanye-Stillwater US PGM Operations are developing a robust Asset Management Plan which is expected to be implemented in FY2022. Pre-use checks for all equipment are carried out and logged by the machine operator. Each piece of equipment has a unit number, which is entered into the management system. Equipment performance is logged daily by the operator onto the log sheet, which is uploaded into the system. The maintenance schedule flags equipment for weekly or monthly maintenance. The planned maintenance system records all equipment on the system for availability, utilisation, unit cost, age and planned replacement per the policy for that classification. Job cards are uploaded into the system to ensure each unit has a history of replacements done. The mine keeps over 500 maintenance items on the system. Shop Availability Maps are used by the mine to assist in planning and updating the status of work in the underground workshops. The overall physical map, including all workshops, is updated by the Workshop Foreman daily to ensure that production teams know the status of repairs/maintenance on the equipment. The Maintenance Department has a target of 80% availability for its major mobile equipment. This percentage is an acceptable standard in industry for underground production and development fleets, although higher availabilities have been achieved at other mines. The unit utilisation is generally lower than industry norms due to the geographical spread of the mining operations. In addition, Stillwater Mine has found it more cost effective to provide more equipment than available at other mines (particularly the equipment that is not readily mobile such as bolters and drill rigs) to save on transport between the geographically spread underground production workings. Buildings Several new or modified buildings are required to support the production ramp up at Stillwater Mine. The following buildings were included in the expansion or modification plan: • Expansions: warehouse, core shed and offices to support additional personnel; and • Modifications: dry-house. Significant expansion of the warehouse at Stillwater Mine (7 500 square feet), implemented in 2019, was needed to accommodate the additional mine and concentrator consumables. 170 The dry-house, relocated ambulance/rescue facility and expanded foreman offices are included in the North Multi-Service Wing. This Multi-Service Wing expansion was completed in FY2021, and includes: • Seven new beat rooms; • Renovated dispatch area with a “high-tech” control room; • Two-bay ambulance garage; • Medical area; • Mine rescue area; and • Five offices for foremen. The core shed handles all drillcore from the drilling and ore control related to the mine development and mine operations. The production ramp up approximately doubled the volume of core requiring handling and logging. The core handling area was consequently expanded within the existing structure to add 1 400 square feet, which displaced the ambulance, paramedic and rescue area. The core shed expansion was also completed in late FY2021. A geology and engineering office expansion was also completed, and this supports the additional Engineers and Geologists needed for the expanded operations. Figure 67 shows the overall site layout for Stillwater Mine. 171 Figure 67: Stillwater Mine Site Layout Transportation Personnel transportation to the Stillwater Mine is a combination of company supplied bussing and light vehicles, and personal vehicles. Transportation of salaried personnel is primarily by company owned light vehicles. Based on the current light vehicle to salaried personnel ratio, no additional light vehicles will be required for future mine plans. Hourly personnel travel to and from site either by company bussing or personal carpools. With employment growth and traffic commitments, additional busing is anticipated for the future mine plans.
172 East Boulder Mine Complex Concentrator Infrastructure The processing plant infrastructure at East Boulder Mine was built in 1999. The plant infrastructure is in a good condition, with the plant having been operated below nameplate capacity since establishment. Appropriate sustaining capital budget provisions have allowed for the undertaking of routine planned maintenance according to the JD Edwards Maintenance Control system. The power supply to the concentrator plants is described in Section 17.2.3. Tailings Storage Facilities The TSF at the East Boulder Mine comprises two cells of a single slimes impoundment as the current primary storage. Stage 1, comprising Cell 1, was operated from 2001 to 2007 after which Cell 2 became the primary deposition facility (Stage 2). Stage 3 is an embankment lift of Stages 1 and 2 and was operated from 2014 through 2020. Stage 4 is an additional embankment lift and is currently active. Beyond Stage 4, the East Boulder TSF has two additional embankment lifts permitted and approved – Stage 5 and Stage 6. Concentrator tailings are sampled and pumped to the underground sand plant where it is classified into coarse sand and slimes fractions. The sand remains underground and is pumped into stopes for backfilling purposes, whilst the slimes fraction is pumped back to surface. The slime is then pumped via one ten-inch pipeline to the TSF for deposition. Deposition on the TSF is via periodic rotational discharge of tailings slurry around the perimeter of the facility using a group of spigots. Once a localised tailings beach has formed, deposition is transferred to another group of spigots at a different location. Water reclamation is achieved via three inclined reclaim pumps and pipelines located on the south- western embankment of the TSF, closest to the concentrator, which discharges into the reclaim water tanks at the concentrator. All stages of the TSF are geomembrane lined. Basin underdrain and seepage measurement is performed and monitored via vibrating wire piezometers whereas embankment crest-mounted survey monuments are used to measure slope slippage or movement. Additional inclinometers are installed around the base of the impoundment to monitor deeper ground movement and displacement. The basin underdrain pore pressures are monitored on a weekly basis via the piezometers, and these respond quickly to changes in the basin underdrain pumping rate. Water drainage results in changes in the tailings mass consolidation and hence maximises storage availability and assists in long-term closure planning. The concentrator performs weekly, monthly and quarterly TSF inspections and monitoring per its standard procedures which are reviewed as part of the annual inspection of the TSF performed by Knight-Piésold. The most recent inspection was performed in October 2021, with surveillance data collected during the January to September 2021 period, and this raised no material issues. As part of the annual inspection of the East Boulder TSF, Knight-Piésold calculated a projected fill rate of the current and planned TSF capacity as an elevation above mean sea level by year. Stage 5 and Stage 6 173 lifts are already permitted and under construction as discussed. The embankment crest maximum elevation of Stage 5 has been calculated by Knight-Piésold as 6 325ftmamsl, whilst the Stage 6 crest has been estimated at 6 344ftmamsl. The Qualified Person notes that, due to the increased tonnages planned to be treated following the conclusion of the Fill The Mill Project as well as changes to the impoundment pond volumes and percentage of tailings sent to backfill, the Stage 4 elevation limit of 6 315ftmsl may be reached sooner than originally planned. Based on Knight-Piésold’s current filling calculations, the Stage 4 limit is estimated to be reached in January 2023, which does not allow sufficient time for Stage 5 construction and preparation to be completed. As a result, an interim overflow channel will be installed, which will extend the capacity as indicated in Figure 68. The Qualified Person considers the design and capacity filling calculations for the TSF to be appropriate and to take cognisance of the planned production. Figure 68: East Boulder TSF Calculated Elevation Profile The Stage 5 and Stage 6 lifts are currently under construction, with Stage 5 on schedule to be completed in FY2023 and Stage 6 scheduled for completion in FY2025. The Stage 5 and Stage 6 foundation preparation and infrastructure relocation are scheduled for completion in FY2022. This work includes relocation of soil piles, fencing, underdrain collection basin, nitrogen collection pond, recycle pond and Pumphouse 1, main overhead powerline, mill overhead powerline, guard shack and gate, transformers, 174 fiber, Boe Ranch pipeline and vaults, underdrain pipeline, nitrogen pond pipeline, groundwater well pumpback system, inclinometers, warehouse septic system, surface electrical building, fire hydrants, wash bay, burn pit, laydown yard, equipment ready line, mill fuel storage, and mine access road. The Qualified Person is satisfied with the $21.3 million capital budget for the Stage 5/6 lifts over the FY2022 to FY2025 period, and capital allowance for new TSFs (e.g., Lewis Gulch TSF) that will be required in future. Power Power to East Boulder Mine is fed from the North West Energy’s 161kV powerline via a tap located north of Springdale and then via the Duck Creek Substation. Park Electric, a power co-operative, supplies power to the mine site and owns the distribution facilities. The power feed from Duck Creek to McLeod and from McLeod to the mine is via a 69kV powerline. Sibanye-Stillwater owns two main substations situated at East Boulder Mine. The mill transformer is a 15/20MVA 69kV to 4 160V and the mine operations transformer is a 10/14MVA 69kV to 13.8kV. There are no spares for either transformer, but there is a cross feed between the two substations which is rated for 8MW. Dedicated capacity for East Boulder Mine is 16MW at a unity power factor contracted from Park Electric, which is adequate for the increased production levels associated with the Fill the Mill Project. East Boulder power loads are currently as follows: • Mine and surface: 7MW at a 0.91 power factor (approximately 77% of maximum capacity); • Concentrator: 5.5MW at a 0.93 power factor (approximately 40% of maximum capacity); and • Monthly Maximum Peak: 12.5MW at a 0.91 power factor. There are two main feeders that feed the underground switchgear from the surface switchgear. Normal operation is to use one feeder and have the other feeder available as a backup. One feeder is installed in Tunnel #1 and the second feeder installed in Tunnel #2. Current underground load is approximately 5MW at a 0.80 power factor. Each of these feeder cables have a loading capacity of approximately 7MW (assuming a 5% maximum voltage drop). East Boulder Mine has two 2MVA Caterpillar 3516B diesel generators which were installed in 2001 at the portal on surface. These generators are currently permitted only as emergency generators, which should be operated for at most 500 hours per year. The generators are designed to operate at the same time in parallel and share the load. When running in parallel, the continuous load on these generators is limited to 3.5MW to allow for peak demands of less than 4MW. Bulk Water 17.2.4.1 Water Supply The water supply for the East Boulder Mine is a mix of fresh make-up water from groundwater supply wells, recycled water from the water treatment facilities and ground water encountered during mining operations. The overall water balance is positive, and disposal of surplus water is required. 175 The groundwater supply wells include the potable water system which provides potable water to the surface operations only and the freshwater system which provides fire water for surface operations and reagent make-up water for the mill. Onsite, the water is reticulated to various sites through a network of pipelines (distribution system). Water consumption from the wells is approximately 50gal per minute and is not expected to increase significantly in future. Water Right Permits allow for beneficial use of up to 262gal per minute from mine water and up to 200gal per minute from potable wells. Treatment and discharge to percolation is not considered a beneficial use and discharge through the Montana Pollutant Discharge Elimination System permit is not included in the water right quota. Current water rights, therefore, are sufficient to support the mine plan. 17.2.4.2 Water Treatment The water treatment system at East Boulder Mine treats and discharges mine water from the underground mining operations. The current system was designed to treat approximately 750gal per minute of water from the underground mining operations. Mine water is first clarified, with a portion recycled to the underground drill water reservoir while the remaining water continues to the biological water treatment process to remove nitrates and ammonia. Treated water is split between recycling for mine use and disposal by percolation to groundwater, based on operational demands. In late FY2015, East Boulder Mine received a new Montana Pollutant Discharge Elimination System (Water Discharge) permit, which stipulated stringent metals discharge limits. The permit allows for a five- year interim period for treatment system evaluation and improvements before the new discharge limits apply. For compliance, the drilling of a deep injection test well was undertaken and successfully tested. The testing of an existing 45 000ft pipeline from East Boulder Mine site to the injection well system was also completed and commissioned in FY2020. This pipeline was designed to carry treated mine water effluent to an injection well at the Yates Gravel Pit for compliance with the discharge limits. 17.2.4.3 Septic System The East Boulder Mine wastewater treatment facility was originally designed and permitted in 1998. The system serves the upper bench office buildings and the concentrator. The design basis for the original system was 600 employees with a peak per capita flow rate of 15gal per day (i.e., 9 000gal per day for the whole mine). The system consisted of approximately 700ft of 8-inch diameter PVC gravity sewer, combined septic dose tank, and two zone conventional drain field with each zone having thirteen 100ft long laterals. In 2006, the collection system was expanded to include a Mobile Dry Building which was included in the original design of 600 employees. The 2006 improvements also made modifications to the existing drainfield to correct ongoing maintenance issues. The 2006 drainfield modifications consisted of replacing the existing conventional drain field with trench infiltrator chambers, adding one lateral to each zone of the drainfield for a total of twenty-eight 100ft long laterals, updating dose pumps and controls, and reducing the drainfield application rate from 1.2gal per day/ft2 to 0.8gal per day/ft2 (due to updated regulations).
176 In FY2015, measured flow tests resulted in an approximate daily flow rate of 9 000gal per day with peak daily flows of 11 000gal per day. Permitting to accommodate the increase is complete as well as the upgrade of the existing wastewater treatment system to 11 000gal per day. The improvements have increased the septic and dose tank capacity and controls. Roads East Boulder Mine is located approximately 25 miles south of Big Timber. The mine is accessed from Big Timber via the paved State Highway 298 and the unpaved East Boulder Road maintained by Sibanye- Stillwater. The road network on the East Boulder Mine site consists of unpaved roads which are primarily used for the transport of logistics and stores for the functioning of the mine and for transport of personnel for access to the infrastructure positioned around the mine site. Buildings East Boulder Mine has adequate modern, fit for purpose offices for administration, technical and personnel services. The mine also has a change house in proximity for the use of mine staff as well as drill core processing and storage facilities. The processing plant has an additional separate small control office facility for operational staff. Likewise, the surface engineering workshops have small operational offices within the workshops. The mine provides adequate secure parking in a gravel parking area adjacent to the main office entry. The mine complex is fenced, with the complex accessed from a security guard manned main gate. Figure 69 shows the overall site layout for East Boulder Mine. 177 Figure 69: East Boulder Mine Site Layout Equipment Maintenance East Boulder Mine also makes use of the JD Edwards Planned Maintenance system, with the robust Asset Management Plan, which is currently under development and already discussed, expected to be implemented in FY2022. The mine has two workshops on surface, which are the following: • Surface Locomotive Workshop: This has a single bay service and mechanical repairs facility for all rolling stock, and includes facilities for work on wheels and engines on the locomotives and ore cars; and 178 • Surface Engineering Workshop: This has multiple bay service and mechanical repair facilities for surface trucks with full machining, welding and electrical maintenance facilities. The mine has the following workshops underground: • 6500 Level Workshop: This has multiple-bay facilities and carries out repairs for both mechanical and electrical faults and maintenance. It also provides a service facility for the rail bound equipment and the adjacent sandfill plant. The workshop is equipped with separate wash bay, office area, warehouse and fuel store. Major overhauls are carried out in the surface workshops; • A small service bay at 68780 Level. • 7900 Level Mobile Workshop: This is primarily for the mobile equipment in the upper mine. It has an ambulance and medical support centre and adjacent refuge bay. This is expected to be a permanent workshop for the life of the mine. All the underground workshops are well-equipped with good lighting, clean concrete floor areas for maintenance, wash bays to ensure quality inspections, and are stocked with the appropriate tools and lifting equipment. Transportation Personnel transportation to East Boulder Mine is a combination of company supplied bussing and company supplied light vehicles. Current company policy mandates the use of company supplied bussing for hourly personnel. Transportation of salaried personnel is primarily by company owned light vehicles. Based on the current light vehicle to salaried personnel ratio, no additional light vehicles will be required for future mine plans. Dry Fork Waste Rock Storage Area In conjunction with the construction of new and expanded tailings facilities, a new waste rock storage area has been designed. The proposed Dry Fork Waste Rock Storage Area is included in the permitting of the Lewis Gulch TSF within Amendment 004. Approval is not anticipated until early FY2024. The Stage 5 TSF lift will need to be completed in the summer of FY2025 under the current mine plan. Upon completion of the Stage 5 TSF embankment lift and lining, all waste rock will need to be placed in the Dry Fork Waste Rock Storage Area. Construction of Phase 1 of the Dry Fork waste rock storage area is scheduled for FY2024 based on anticipated regulatory approval which will be permitted as part of the Lewis Gulch TSF. A bridge and access road will be constructed at the start of Phase 1 in FY2024 Columbus Metallurgical Facility The Columbus Metallurgical Complex, which houses the smelter, base metal refinery, laboratory and recycling plant, was built on freehold owned by Sibanye-Stillwater. The building and stack heights are limited due to the proximity of the light aircraft field. The facilities are secured by fencing and access is limited to card holding employees. The Columbus Metallurgical Complex includes well-established automated sampling and sample processing facilities with a robotic operated sample laboratory. Office facilities are adequate for the required staff to operate the base metal refinery and smelter. Infrastructure at the Columbus 179 Metallurgical Complex is maintained in a good operational condition through adequate capital provisions for maintenance and upgrades as required. Power supply to these facilities is from North West Energy at the standard 100kV at the main switch station and two-step down transformers. Sibanye-Stillwater keeps a spare transformer onsite and, therefore, power supply is reliable.
180 MARKET STUDIES Introduction PGMs (also referred to as Platinum Group Elements or PGEs) comprise platinum, palladium, rhodium, ruthenium, iridium and osmium. The Bushveld Complex in South Africa contains approximately 80% of the known global PGM mineralisation and produces approximately 80% of the world's annual PGM supply from the UG2 and Merensky Reefs. The J-M Reef mined at Stillwater and East Boulder Mines is the sole source of primary palladium and platinum production in the USA, accounting for approximately 5% of the world annual primary PGM supply. PGM mineralisation in the J-M Reef is dominated by palladium and platinum, with other PGMs occurring in negligible quantities. Information on PGM markets is widely available in the public domain. Major refiner and manufacturer of products using PGM, Johnson Matthey, regularly publishes market reports. In addition, Sibanye- Stillwater commissioned an independent PGM market study by its research company, SFA Analytics (SFA Oxford), which was completed in March 2021. Information from these sources along with negotiated contracts inform Sibanye-Stillwater’s price and sales predictions. Given that palladium and platinum account for almost 100% of the revenue generated at Stillwater and East Boulder Mines, this market review focuses on these two metals. PGM Market Overview During the first half (H1) of the 2021, primary supply constraints buoyed prices. Despite Anglo Platinum Limited’s Anglo Converter Plant (ACP) Phase A unit being back online since December 2020, extended refining lead times continued to impact primary supply of Rh, Ru and Ir from South Africa during Q1 2021. In February 2021, Norilsk Nickel partially suspended production at its Oktyabrsky and Taimyrsky Mines due to flooding and a fatal accident at its concentrator in the same month, impacting on Pd output. Oktyabrsky resumed normal operations in May 2021, with Taimyrsky only back to full production in December 2021. Primary producers were on the market as Rh and Pd buyers during H1 2021. Overall, primary supply recovered to normal, pre-covid levels by year end. The global semiconductor chip shortage which began to emerge in 2020 worsened during 2021 and was at its most severe just as global supply recovered. Chip supply for automotive manufacturing was impacted by severed winter storms in the USA, ongoing covid-19 disruptions in Southeast Asia and a fire at a chip fabrication facility in Japan. The chip shortages, combined with more general supply chain constraints has impacted OEMs across the world, with temporary stoppages at many production facilities. Although OEMs prioritised the production of higher margin, larger engine vehicles that contain higher PGM loadings, light vehicle production is expected at approximately 74.5 million units for the year, well below 2019 levels of 86.5 million and only 3% higher than 2020 levels of 72.2 million. New car inventory in the USA reached an all-time low during the year, while used car prices rocketed. Although chip fabrication capacity has improved and the worst seems to be over, PGM demand for autocatalysts was negatively impacted and reduced vehicle scrappage rates are expected to impact on recycling. Battery Electric Vehicles' (BEVs') share of light duty vehicles grew from 3% in 2020 to 5% in 2021 at the expense of gasoline vehicles, further impacting Pd and Rh demand for autos. 181 Platinum and Palladium Demand and Supply Demand Drivers The main uses of platinum are as a catalyst for automotive emissions control, in a wide range of jewellery pieces and in industrial catalytic and fabrication applications. Palladium is primarily used as a catalyst in the automotive sector, mainly in gasoline-powered on-road vehicles, but alongside platinum in parts of the light-duty diesel engine after-treatment too. The second main use of palladium is in electrical components, specifically in multi-layer ceramic capacitors (MLCCs), as conductive pastes and in electrical plating. Platinum Pt started the year at $1 113/oz, peaking at $1 325/oz in February 2021 and dropping as low as $925/oz by December 2021 as OEMs and fabricators looked to end the year with low inventories. Primary platinum supply grew 20% year-on-year (y-o-y) to the 2019 levels of 6Moz as South African supply returned to the pre-Covid 19 pandemic levels, while secondary supply grew 4% y-o-y with limited price incentives to return Pt to the market. Auto demand remained 6% below the 2019 levels while industrial demand for Pt grew 7% y-o-y to 2019 levels as global economies recovered and substitution in the glass industry continued. Net jewellery demand for Pt fell 6% y-o-y to 1Moz driven by declines in China and India. The platinum market is forecast to move into a surplus of approximately 990koz at year end, from a deficit of approximately 500koz in 2020. Palladium Pd broke the $3 000/oz mark in May 2021 on the back of the Norilsk Nickel supply concerns, gaining $535/oz from the beginning of the year, but dropping to a low of $1 619/oz during December 2021. Primary supply grew 9% y-o-y but is not yet back at pre-Covid 19 pandemic levels due to Norilsk Nickel’s flooding and concentrator incidents. Secondary supply grew 8% y-o-y, falling slightly below the 2019 levels. Although incentivised by record prices levels in H1 2021, reduced vehicle scrappages and supply chain disruptions continued to impact collection. Auto demand remained flat y-o-y because of the chip shortage while industrial demand grew 7%. Overall, the Pd market is expected to remain a small deficit of approximately 90koz at year end, compared to the approximately 600koz deficit in 2020. Palladium and Platinum Pricing Outlook For business planning and Mineral Reserve estimation, Sibanye-Stillwater uses forward looking prices that it considers will stay stable for at least three to five years, and will significantly change if there is a fundamental, perceived long-term shift in the market, as opposed to basing it only on short term analyst consensus forecasts. Sibanye-Stillwater also considers its general view of the market, the relative position of its operations on the costs curve, as well as its operational and company strategy in its forecasting of forward-looking prices. On a monthly basis, Sibanye-Stillwater also receives an independent report from UBS Bank (Commodity Consensus Forecasts Report) which contains consensus outlooks from the various banks on a broad range of commodities. It benchmarks its forward-looking prices to the market consensus forecast. 182 Table 42 summarises the forward-looking prices of palladium and platinum applied by Sibanye-Stillwater for business planning and Mineral Reserve declaration as at December 31, 2021. This also shows comparison between Sibanye-Stillwater and Market Consensus forward-looking prices. The Qualified Person notes that the comparison shows overall agreement between the price forecasts and, therefore, Sibanye-Stillwater forward-looking prices are reasonable. Table 42: Comparison of Sibanye-Stillwater and Market Consensus Prices Metal Unit Market Consensus Forward Price - 2021 Mineral Reserve Price - 2021 Platinum USD/oz 1 216 1 250 Palladium USD/oz 2 240 1 250 Metals Marketing Agreements The Columbus Metallurgical Complex Sibanye-Stillwater’s wholly owned Columbus Metallurgical Complex is a state-of-the-art operation that provides smelting and refining processes for PGM concentrates from the Stillwater and East Boulder mines. The complex produces a PGM-rich concentrate after base metal refining that is shipped to a third-party precious metal refinery. In addition, the complex facilitates recycling operations for various materials containing PGMs, principally automotive catalytic converters that are provided by third-party suppliers under arms-length commercial offtake or toll treating contract terms. Precious Metals Refining With the exception of certain metal sales commitments, all of Sibanye-Stillwater US PGM Operations’ current mined palladium and platinum are contracted for sale to a third-party precious metals refinery. In addition, this third party has the right to bid on any recycling PGM ounces Sibanye-Stillwater has available in the United States. Wheaton International Streaming Agreement In 2018, Sibanye-Stillwater announced the completion of the Streaming Agreement with Wheaton International. Under the Streaming Agreement, Sibanye-Stillwater received US$500 million (the Advance Amount) from Wheaton in exchange for an amount of gold and palladium equal to a percentage of gold and palladium produced from Sibanye-Stillwater’s Stillwater and East Boulder mines. Under the Streaming Agreement, in addition to the Advance Amount, Wheaton International will pay Sibanye-Stillwater 18% of the US dollar spot palladium and gold prices for each ounce delivered under the Streaming Agreement until the Advance Amount has been reduced to nil through metal deliveries. Thereafter, Sibanye-Stillwater will receive 22% of the spot US dollar palladium and gold prices for each ounce of palladium and gold delivered. In both cases, the payments by Wheaton International may be reduced if debt covenants exceed three and half multiples of the net debt to adjusted Earnings Before Interest, Taxes, Depreciation and Amortisation (EBITDA) ratio. In addition, Sibanye-Stillwater has committed to deliver to Wheaton the equivalent of 100% of gold production from Sibanye-Stillwater’s US PGM Operations over the life of the operations. Furthermore, Sibanye-Stillwater has committed to: 183 • Delivering 4.5% of its palladium production from its Sibanye-Stillwater US PGM Operations, until: o A cumulative amount of 375koz of palladium has been delivered; and o The portion of the Advance Amount, which is attributable to palladium deliveries having been reduced to nil through such deliveries. • Thereafter, deliver the equivalent of 2.25% of its palladium production from the Sibanye-Stillwater US PGM Operations until: o A further 175koz of palladium having been delivered (or cumulatively 550koz having been delivered); and o The Advance Amount having been reduced to nil through metal deliveries. • Thereafter, and continuing for the life of the operations, deliver 1.0% of palladium production. Sibanye-Stillwater agreed to use commercially reasonable efforts to facilitate the development of the Blitz Project. The Streaming Agreement includes a completion test on the development of the Blitz Project, including completion of underground development, critical surface infrastructure and expansion of the concentrator production output. If Sibanye-Stillwater fails to meet certain completion targets in relation to the Blitz Project, it is required to pay Wheaton certain cash amounts. The Streaming Agreement, with an effective date of 1 July 2018, continues for an initial period of 40 years and can be extended for successive 10-year periods until termination notice is given or there are no active mining operations at the Sibanye-Stillwater US PGM Operations. The Qualified Person notes that the Streaming Agreement is material to the Sibanye-Stillwater US PGM Operations but sets out conditions that are not excessively onerous and can easily be achieved by Sibanye-Stillwater if the current LoM plans for Stillwater and East Boulder Mines are executed as planned. The 2020 Palladium Hedge On 17 January 2020, SMC (the wholly owned subsidiary of Sibanye-Stillwater operating as the Sibanye- Stillwater US PGM Operations) concluded a palladium hedge agreement commencing on 28 February 2020, comprising the delivery of 240koz of palladium over two years (10koz per month) with a zero-cost collar which establishes a minimum floor and a maximum cap of US$1 500 and US$3 400 per palladium ounce, respectively. Given the short duration of the hedge agreement, the Qualified Persons note that the palladium hedge is not material to the economics of the LoM cash flows for the Sibanye-Stillwater US PGM Operations.
184 ENVIRONMENTAL STUDIES, PERMITTING, PLANS, NEGOTIATIONS/AGREEMENTS Social and Community Agreements In order to assist in managing Sibanye-Stillwater’s Social Licence to Operate, a progressive and effective Good Neighbor Agreement was signed in 2000 and this agreement was amended in 2005, 2009, and 2015. The Good Neighbor Agreement is a legally binding contract between Sibanye-Stillwater, the Northern Plains Resource Council, Cottonwood Resource Council and Stillwater Protective Association, which is binding on current and future owners and managers of the Stillwater and East Boulder Mines. It provides an avenue for the citizen groups to access information on the Stillwater and East Boulder Mines and to participate in decisions on the operations that may impact the local communities, economies, or environment. In essence, it provides for citizen oversight of Stillwater and East Boulder Mines to guarantee protection of the area’s quality of life and productive agricultural land and allows for local communities to have access to critical information about mining operations and the opportunity to address potential problems before they occur. Furthermore, it requires the information to be sufficiently detailed to permit assessment of potential environmental and social impacts. Both Stillwater and East Boulder Mines have a Good Neighbor Oversight Committee that meets three times per year. In addition to these formal, transcribed meetings, a Technology Committee and other committees meet as needed but communicate weekly to address ongoing projects. This constant stakeholder engagement enables citizens to meaningfully engage in the permitting and mine planning processes and provide feedback in advance of formal comment periods. This approach allows Sibanye-Stillwater to adjust its permitting strategy to address stakeholder concerns, where necessary, and effectively reduce the potential permitting delays and negative comments during public comment periods. A primary focus of the Good Neighbor Agreement is water quality, and under the agreement, the Stillwater, and East Boulder Rivers are closely monitored for changes in water quality. The agreement sets water quality triggers that meet or exceed the state and federal requirements. If a Good Neighbor Agreement water quality trigger is exceeded, Sibanye-Stillwater will take the appropriate remedial actions as defined in the agreement. As part of the monitoring, citizens may attend all mine-related water quality inspections and sampling events but are also provided with quarterly water quality reports. A provision is also made for the citizens to conduct independent water quality sampling, if necessary. The Good Neighbor Agreement is also aimed at ensuring public safety and security by restricting mine traffic and monitoring Sibanye-Stillwater’s adherence to the permitted traffic volumes and speed limits. In order to meet traffic requirements, the agreement provides for carpooling and bussing as a preferable means of transport for mine employees. These arrangements also afford mine workers additional rest time and keep tired drivers off the road. 185 Other aspects of the Good Neighbor Agreement include: • Establishing conservation easements on Sibanye-Stillwater owned ranches along the Boulder and Stillwater Rivers; • Preventing any mine sponsored housing occurring outside existing communities; and • The Good Neighbor Agreement contains no commitments in terms of local procurement and employment. The Qualified Persons are satisfied with Sibanye-Stillwater’s commitment to working with federal and local administrations, organisations and community and conservation groups to ensure that Stillwater and East Boulder Mines adhere to the Good Neighbor Agreement. Furthermore, the mine plans for Stillwater and East Boulder Mines ensure that commitments made in the Good Neighbor Agreement are not breached. Accordingly, the Qualified Persons are of the view that Sibanye-Stillwater should be able to maintain its Social License to Operate the Stillwater and East Boulder Mines for as long as it continues to actively engage other stakeholders and to honour conditions and commitments specified in the Good Neighbor Agreement. Grazing leases for lands purchased at the Hertzler Ranch area (Ekwortzel Purchase) for Stillwater Mine are tied into the land purchase agreement with the previous landowner and there are no other social or community agreements. Environmental Studies, Permitting and Plans Overview of Environmental Legislation and Regulation Operations at Stillwater and East Boulder Mines are regulated by the State of Montana agencies including the Montana Department of Environmental Quality (DEQ); Department of Natural Resources and Conservation (DNRC); as well as Federal agencies including the Custer Gallatin National Forest (CGNF); US Environmental Protection Agency (EPA); US Bureau of Alcohol, Tobacco and Firearms (ATF); US Army Corps of Engineers; US Federal Communications Commission (FCC); and US Nuclear Regulatory Commission (NRC). A list of the agencies and the required permits, licenses or approvals are summarized in Table 43. The regulatory agencies can approve, deny, or conditionally approve applications for mining or modification of permits. State of Montana regulations require that changes to or denial of a permit must be directly related to a specific State law or regulation and are not discretionary. The United States Forest Service (USFS) may deny mining proposals, although this authority is limited by federal law. Several laws (e.g., the 1872 Mining Law as amended and related regulations in Title 36 of the US Code of Federal Regulations (CFR) Part 228A; 1897 Organic Administration Act; and 1955 Multiple Use Mining Act), allow the USFS to reasonably regulate mining to minimize adverse environmental impacts on National Forest surface resources and to ensure compliance with applicable environmental laws and regulations. These laws and regulations include, but are not limited to, the 36 CFR 228 Locatable Minerals Regulations, Subpart A; 1972 Clean Water Act (CWA); and 1973 Endangered Species Act (ESA). The USFS can reasonably regulate mining although it cannot prohibit or unreasonably restrict operations that are otherwise in compliance with law. If analysis performed under the National Environmental Policy Act (NEPA) and other analyses show that a proposed mining activity can operate in a way that is compliant 186 with the applicable environmental laws, the USFS cannot prohibit or deny the proposal on National Forest lands subject to the 1872 Mining Law. The proposals or agency alternatives, if approved, must comply with all applicable federal and state air and water quality laws and regulations. Mine Operating Permits are jointly issued by the State of Montana (DEQ, Hard Rock Mining Program) and the Forest Service, CGNF through a Memorandum of Agreement between the two agencies. The Mine Operating Permits are based on the Plans of Operations submitted by the permittee (which are reviewed by both the State agencies and the CGNF) as well as on the Environmental Impact Statement (EIS) also developed jointly by the DEQ and CGNF, the findings of which are documented in Records of Decision. 187 Table 43: Regulatory Agencies and Permits, Licenses or Approval Requirements Agency, Permit, License, or Approval Purpose US Fish and Wildlife Service (USFWS) Biological Opinion (Endangered Species Act) To ensure actions taken by federal agencies would not jeopardize the continued existence of threatened or endangered species or result in the destruction or modification of critical habitat. The USFS must consult with the USFWS, which issues its Biological Opinion following review of a Biological Assessment submitted by the USFS. US Forest Service (USFS) Biological Assessment Required by the Endangered Species Act prior to the approval of a plan of operations or its implementation. The biological assessment ensures actions taken by USFS would not jeopardize the continued existence of threatened or endangered species or result in the destruction or modification of critical habitat. These are USFS conclusions that usually require USFWS concurrence. Plan of Operations The basis of authorization under statutes administered by the USFS that ensures the design, operation, closure, monitoring, and bonding of mining operations result in adequate operations and reclamation for post-mining land uses. The plan of operations is also needed for activities reasonably incident to mining operations of National Forest lands. Coordination between Montana Department of Environmental Quality (DEQ) and other agencies, as appropriate, per memorandum of understanding between the USFS and Department of State Lands (DSL). The MOU defines the joint administration and bonding of mining operations in Montana with activities on National Forest lands. Executive Order (E.O.) 13007 (Clinton) and Government to Government Relations with Native American Tribal Governments — Memorandum for the Heads of Executive Department and Agencies (April 29, 1994) E.O. 13007 requires that agencies contact Indian tribes regarding effects and the Section 106 regulations require consultation with Indian tribes to identify and resolve adverse effects to historic properties. The Memorandum outlines principles that federal agencies must follow when interacting with federally recognized Native American tribes in deference to Native Americans’ rights to self-governance. Specifically, federal agencies are directed to consult with tribal governments prior to taking actions that affect federally recognized tribes and to ensure that Native American concerns receive consideration during the development of Federal projects and programs. Special Use Permit Allows use of Forest Service Roads Temporary Grazing and Livestock Use Permit Allows non-commercial temporary grazing on Forest Service land FSR Road Maintenance Agreement For situations where the wilderness level of maintenance is not sufficient for a commercial or public user, that user may elect to undertake some or all of the surface maintenance of the FSR as authorized by the Forest Service Road Maintenance Agreement. US Army Corps of Engineers (US ACE) Section 404 Nationwide Permit (Clean Water Act) To control the discharge of dredged or fill material into waters of the US, including wetlands. US Environmental Protection Agency (EPA) Underground Injection Control Permit (Safe Drinking Water Act) EPA regulates the construction, operation, permitting, and closure of injection wells used to place fluids underground for storage or disposal. EPA regulates injection wells at the mines that are used for groundwater remediation and disposal.
188 Agency, Permit, License, or Approval Purpose Delegated Programs EPA has delegated the primary implementation and enforcement authority of the Clean Air Act to Air Resources Management Bureau of DEQ. Similarly, the primary implementation and enforcement authority of the Clean Water Act National Pollutant Discharge Elimination System (NPDES) to the Water Protection Bureau of DEQ under its Montana National Pollutant Discharge Elimination System (MPDES) program. Coordination of these programs is governed by agreements between the EPA and the State of Montana. US Bureau of Alcohol, Tobacco, Firearms, and Explosives (BATFE) Safe Explosives Act The Safe Explosives Act mandated that all persons who wish to receive or transport explosive materials must first obtain a federal explosives license or permit. In addition, the act imposed new restrictions on who may lawfully receive and possess explosive materials. US Bureau of Land Management (BLM) Mineral Claims Under 43 CFR 3700 Part 3800 the BLM manages the subsurface of National Forest lands, while USFS manages the surface. US Mine Safety and Health Administration (MSHA) Federal Mine Safety and Health Act of 1977 as amended by the Mine Improvement and New Emergency Response (MINER) Act Of 2006 Develops and enforces safety and health rules for all US mines regardless of size, number of employees, commodity mined, or method of extraction. MSHA conducts quarterly inspections to ensure safety and health rules are implemented. US Nuclear Regulatory Commission (NRC) Nuclear Density Gauge Permit The NRC licenses the possession and use of portable gauges and any other processes or devices that use radioactive materials. Montana Department of Environmental Quality (DEQ) 401 Certification (Clean Water Act and Montana Water Quality Act) To certify that any activity requiring a federal license or permit that may result in any discharge into State waters would not cause or contribute to a violation of State surface water quality standards. Montana Pollution Discharge Elimination System (MPDES) Permit (Clean Water Act and Montana Water Quality Act) Authorizes discharge to surface water and groundwater adjacent to surface water Operating Permit (Montana Metal Mine Reclamation Act) To ensure design, operation, closure, monitoring, and bonding of mining operations result in adequate reclamation for post- mining use. Coordinate with the USFS, and other appropriate agencies. Storm Water Pollution Prevention Plan (Clean Water Act and Montana Water Quality Act) To prevent the degradation of state waters from pollutants, such as sediment, industrial chemicals or materials, heavy metals, and petroleum products. 189 Agency, Permit, License, or Approval Purpose Short-term Water Quality Standard for Turbidity Related to Construction Activity (318 Authorization of Montana Water Quality Act) To allow for short-term increases in surface water turbidity during construction. Montana Fish, Wildlife, and Parks (FWP) are consulted on this authorization. Air Quality Permit (Clean Air Act and Clean Air Act of Montana) To set allowable air emission rates for both stationary sources and portable emitting units. Non-Community Non-Transient Water Supply (Safe Drinking Water Act and Montana Public Water Supply Act) To ensure safe drinking water supplies for the mine site, and to license the water treatment plant operators. Hazardous Waste Authorization/Classification To allow generation of less than 200lbs of hazardous waste per month as a Conditionally Exempt Small Generator Montana Department of Natural Resources and Conservation (DNRC) Land Use Licenses To permit the construction of access roads and pipelines across State of Montana lands Dam Safety Permit (Montana Dam Safety Act) Montana's Dam Safety Law requires a dam safety permit for all high-hazard dams. DNRC classified high-hazard dam is a dam with an impoundment capacity of 50 acre-feet or more based on the potential downstream loss-of-life if the dam fails. Water Right Permits (Montana Water Use Act) To permit the legal use/appropriation of water at Stillwater Mine for specified industrial, mining, and water supply beneficial uses. Montana State Historic Preservation Office (SHPO) Historic Resources Consultation (National Historic Preservation Act) To obtain joint approval by land-managing agencies and concurrence by the SHPO before agency approval; reviewed by the Advisory Council on Historic Preservation. Montana Department of Commerce Hard Rock Mining Impact Board Hard Rock Impact Plan To ensure that local government services and facilities will be available when and where needed as a result of new large-scale hard rock mineral developments and that the increased cost of these services will not burden the local taxpayer. The developer identifies and commits to pay all increased capital and net operating costs to local government units that will result from the mineral development. Performed in cooperation with counties, school districts and rural fire districts. County Conservation District 310 Permit (Montana Natural Streambed and Land Preservation Act) To protect and preserve streams and rivers in their natural or existing state. Application processed in consultation with Montana Department of Fish, Wildlife, and Parks. County Road Department Application to Perform Construction Work in a Right-of- Way To permit construction and maintenance of the pipeline along county roads. 190 Environmental Setting and Factors Nye and Absarokee are the closest towns to Stillwater Mine, while McLeod and Big Timber are the closest towns to East Boulder Mine. Facilities at Stillwater Mine are located on both sides of the Stillwater River, which flows southwest to northeast. East Boulder Mine is located on the south side of East Boulder River, which flows north along the mines’ eastern edge and then northwest along the current mine’s northern edge. The East Boulder Mine TSF lies between the Dry Fork Creek and Lewis Gulch drainages. The Columbus Metallurgical Complex is located approximately one-half mile north of the Yellowstone River. The protection of groundwater and surface water is the primary environmental factor for environmental compliance at the Sibanye-Stillwater’s mine facilities. At the Columbus Metallurgical Complex, the primary environmental factor is air quality compliance. Additional environmental factors include air quality, vegetation, soil, geology and geochemistry, wildlife, aquatic resources, cultural resources, aesthetics and land use. In addition, community approval is often a key factor. The host rock for the J-M Reef has very low acid-generating potential and low metal solubility. This low solubility has minimised potential environmental impacts from the substantial scale of these operations. However, ammonia (NH3), ammonium (NH4+), and nitrate (NO3-) are soluble residual constituents from the ammonium nitrate/fuel oil (anfo) used in mining and have been observed to be present in mine adit waters as well as in leachate from waste rock and tailings. These are the primary potential groundwater and surface water contaminants at the Stillwater and East Boulder Mines. The Stillwater and East Boulder Rivers adjacent to these mines are the principal resources that may be adversely affected by mining operations, although historical and cultural resources are also known to exist within the current and planned mine disturbance areas. The river water quality is high and there is no evidence of adverse impacts to aquatic or terrestrial wildlife populations, although the rivers have measurable loading of nitrates and dissolved solids from mining operations resulting in localised impairment of periphyton and macroinvertebrates. The Stillwater and East Boulder Rivers are considered substantial fishery resources and host brown trout, rainbow trout, brook trout, and mountain whitefish (DEQ and USFS, 1985). Overall, both rivers have good insect and periphyton diversities and densities. Environmental Studies 19.2.3.1 Overview of Baseline and Environmental Studies Extensive baseline and recent environmental studies have been completed since the 1930s for Stillwater Mine and 1982 for East Boulder Mine. For Stillwater Mine and the East Boulder Mine, these entailed surface water and groundwater studies, vegetation studies, wildlife studies, aquatic studies, cultural resource studies, land use studies, aesthetic value and noise studies as well as geological studies. Additional environmental studies were completed in 2019 through 2021 for the expansions at both mines. The content and results of these numerous studies are too voluminous to reproduce herein and, therefore, summaries of key environmental areas are provided below. 191 19.2.3.2 Stillwater Mine and Hertzler Ranch Facilities Extensive environmental baseline and operational monitoring studies have been performed at Stillwater Mine. The 1985 Environmental Impact Study (EIS) for the Stillwater Mine identifies thirteen vegetation types in the study area, along with water and disturbed areas with no vegetation (DEQ and USFS, 1985). These vegetation types include stony grassland, Sagebrush and Skunkbush shrubland, drainage bottomland, riparian woodland, ravine aspen-chokecherry, open forest-meadow understory, open forest-rocky understory, Douglas-fir forest, Lodgepole pine forest, subalpine forest, and cultivated hayland. Timber resources in the mine areas are described generally as being of low commercial value due to poor quality timber and the rugged terrain's limits on harvest operations. Wildlife studies indicate that the mine areas support diverse and abundant wildlife populations, including bird, mammal, reptile, amphibian, and aquatic species. The mine areas provide winter ranges for elk, mule deer, and bighorn sheep. In addition, the mine area habitats also host moose, black bear, mountain goats and mountain lions. Wildlife habitat types correspond closely to vegetation types previously described. Both the Bald Eagle and the American Peregrine Falcon, which were identified as listed species in the 1985 Stillwater Mine EIS, have been de-listed due to the recovery of their populations. Geochemical studies and operational environmental monitoring data demonstrate that the waste rock mined throughout the history of production at the Stillwater and East Boulder Mines have negligible potential to generate acid or acid mine drainage. Concurrent leach testing of over 40 parameters including 29 trace metals from tailings and waste rock indicates that dissolved trace metal concentrations will not exceed current groundwater protection standards. Decades of operational environmental monitoring data are consistent with this testing. However, ammonia (NH3), ammonium (NH4+), and nitrate (NO3-) are soluble residual constituents from the anfo (ammonium nitrate/fuel oil) used in mining and have been observed to be present in mine adit waters as well as in leachate from waste rock and tailings. These are the primary groundwater and surface water contaminants at the Stillwater and East Boulder Mines. The most recent Stillwater Mine environmental studies have addressed baseline biological conditions in Nye Creek and the Stillwater River, groundwater conditions at the Hertzler TSF, climatological conditions, and wetlands delineations at the East Waste Rock Storage Facility expansion area. These studies have been reviewed and accepted or are in review by the regulatory agencies (i.e., DEQ, USFS and USFWS) and to date have been deemed adequate to document baseline conditions for groundwater, surface water, soils, geology and geochemistry, vegetation, wildlife, aquatic resources, cultural resources, aesthetics, and land use to support regulatory approval of ongoing operations. Table 44 identifies the recent environmental studies executed as part of the mine expansion efforts. Tables identifying applicable baseline studies are included in the Consolidated Operations and Reclamation Plans for Stillwater Mine.
192 Table 44: Summary of Recent Environmental Studies Associated with Expansions at Stillwater Mine Date Description 2019/01/15 Nye Creek Biological Baseline Summary: Fish, Macroinvertebrates, Periphyton and Chlorophyll-a Sampling 2019/08/30 Climatological Site Conditions 2019/09/25 East Boulder Mine Geological and Geotechnical Site Conditions 2019/12/01 Draft Vegetation Baseline: (ESWRSF & Hertzler TSF) 2019/12/16 Analysis of Stillwater Valley Ranch Trout Ponds as a Receiving Water for Discharges to the SVR Percolation Ponds 2020/01/01 Biological Resource Survey; brief reconnaissance of biological resources of Hertzler TSF and ESWRSF; the expansion sites and Stillwater Mine vicinity do not support preferred and/or breeding habitat and preferred and/or breeding habitat is available in the vicinity 2020/03 Biological Assessment of Sites in the Stillwater River Drainage, Stillwater County, Montana: Macroinvertebrates, Periphyton, and Chlorophyll a, 2019 2020/06/25 Cultural resource survey results 2020/06/25 Mine East Dump; Cultural resource survey results 2020/06/30 Aesthetics/Viewshed 2020/12 Biological Assessment of Sites in the Stillwater River Drainage, Stillwater County, Montana: Macroinvertebrates, Periphyton, Chlorophyll a, and Periphyton Ash-Free Dry Mass 2020 2021/01/18 Wetland Delineation Report for the ESWRSF 2021/01/26 Seismic Refraction and MASW Survey, Nye, Montana Logistics, Processing, and Interpretation Report 2021/01/29 Geological and Geotechnical Site Conditions - Hertzler Ranch 19.2.3.3 East Boulder Mine Baseline data for East Boulder Mine was collected between 1982 and 1992 to support the 1992 Environmental Impact Statement. Additional baseline data was collected between 1997 and 2018 to support water management and additional expansions at the mine. The geology of East Boulder Mine comprises unconsolidated alluvium and glacial deposits overlying Palaeozoic sedimentary bedrock and igneous bedrock of the Stillwater Complex (DEQ and USFS, 2020). Groundwater in the Stillwater Complex occurs primarily in an extensive network of joints, fractures and fault zones resulting in slow groundwater flow. The glacial deposits vary in grain size and are a mixture of boulder, gravel, sand and silt sized particles, which result in variable groundwater flow rates. The majority of recharge to the underlying glacial deposits and bedrock is understood to occur through the alluvial deposits (DEQ and USFS, 2020). Groundwater occurs beneath the East Boulder Mine at depths from 120ft to 150ft below the ground surface but follows the ground surface and becomes shallower near the East Boulder River (DEQ and USFS, 2020). Groundwater flows from southeast to northwest parallel to the axis of the valley that contains the East Boulder Mine. The groundwater quality in the East Boulder Mine footprint has low total dissolved solids concentrations and low concentrations of sulphate, chloride and heavy metals. The East Boulder River adjacent to the East Boulder Mine is characterized by riffles and pools. Peak flows in the East Boulder River result from snowmelt and precipitation. The river loses water to the groundwater system northeast of the permit area and gains water from the groundwater system farther downstream along the East Boulder Mine. The water quality of the East Boulder River is good, with low total dissolved solids concentrations. Total dissolved solids concentrations vary with river flow; higher total dissolved solids concentrations are measured during times of lower flow in the winter and early spring. Sampling of the aquatic environment of the East Boulder River for thirteen years identified that the river had 193 excellent biotic integrity and no impairment of water quality of biological integrity resulting from East Boulder Mine operations has been identified. The Lewis Gulch drainage has surface water flow along portions of the drainage in response to snowmelt. Three springs along the Dry Fork drainage flow for distances before infiltrating into the ground. Flowing surface water did not intercept the East Boulder River during baseline studies. The surface water in the Lewis Gulch and Dry Fork drainages is high quality with low total dissolved solids and metals concentrations. Four distinct plant communities are located within the East Boulder Mine boundary. These include Mature Douglas Fir Forest, Early Seral Douglas Fir Forest, Reclaimed Grassland, and Meadow Grassland. No threatened or endangered plant species were identified as occurring at the East Boulder Mine. One sensitive species (Whitebark pine) was identified in the area of the proposed future disturbance at East Boulder Mine. The most recent East Boulder Mine environmental studies have addressed baseline environmental conditions, cultural resources surveys, wetland surveys, mine groundwater inflow, climatological conditions, and biological assessment of the East Boulder River. The Class III cultural resource inventory study completed in 2021 identified from records seven previously identified cultural sites within the study area but did not identify evidence of those sites in the recent field survey of over 315 acres and no further survey work was recommended. The survey did not identify any sites that would preclude the planned expansions. Wildlife studies indicate that the area around East Boulder Mine supports diverse and abundant wildlife populations. The mine areas provide winter ranges for elk and mule deer. In addition, the mine area habitats host moose, black bear, grizzly bear, and wild trout. Brown trout and rainbow trout are the most abundant species in the East Boulder River (DEQ and USFS, 2012a). The recent baseline study Construction and operation of the TSF and Dry Fork waste rock storage facilities would result in short- term and long-term impacts on wildlife use patterns, wildlife habitat quantities, and vegetative composition. The project may decrease wildlife forage production and availability in the short term due to the removal of vegetation. Possible adverse effects to aquatic resources in the East Boulder River or the perennial or ephemeral streams could result from soil erosion / storm water discharges occurring during construction. However, wildlife carrying capacity may increase in the long-term after the project is complete and the project area is revegetated. All ecological, geological, hydrological, geotechnical, archaeological, and climatological studies appear to be completed for the Lewis Gulch TSF Stage 4 and 5 expansions, the Dry Fork Waste Rock Storage Area and associated haul road and bridge. The baseline studies have been reviewed and accepted by the regulatory agencies after having been deemed adequate to document baseline conditions for groundwater, surface water, soil, geology and 194 geochemistry, vegetation, wildlife, aquatic resources, cultural resources, aesthetics, and land use to support regulatory approval of operations. Table 45 identifies the recent environmental studies executed at East Boulder Mine. Tables identifying applicable baseline studies are included in the Consolidated Operations and Reclamation Plans for East Boulder Mine. Table 45: Summary of Recent Environmental Studies Associated with Expansions at Stillwater Mine Date Description 2019/09/25 Geological and Geotechnical Site Conditions 2020/12 Biological Assessment of Sites on the East Boulder River: Sweet Grass County Montana, 2020 2021/10/14 Climatological Site Conditions 2021/05 Lower Lewis Gulch and Dry Fork Sites Wetland Survey 2021/05 Lewis Gulch and Dry Fork Creek Updated Baseline Hydrogeologic Monitoring Report 2021/06/21 East Boulder Mine Groundwater Inflow Analysis 2021/08 Stillwater East Boulder Expansion: A Class III Cultural Resource Inventory in Sweet Grass County, Montana 2021/08 Baseline Environmental Survey at the East Boulder Mine 2021/10/14 East Boulder Mine Climatological Site Conditions 2021/11 Monitoring of Chlorophyll-a and Periphyton Ash-Free Dry Mass on the East Boulder River, Sweet Grass County Montana, 2021 19.2.3.4 Metallurgical Complex No baseline studies, environmental studies nor impact assessments specific to the Columbus Metallurgical Complex (smelter and base metal refinery) were completed for permitting purposes as these were not required by the regulatory authorities. As there was no public land interaction and associated permitting, an EIS or similar studies were not required for construction and operation of the smelter and base metal refinery. Permitting Status and Compliance 19.2.4.1 Overview of Permitting Status Permits from the Federal, State and local agencies for the Sibanye-Stillwater US PGM Operations include permits from the State of Montana (e.g., mine permit, air quality permit, stormwater discharge permits, water discharge permits, exploration permit, and potable water supply permit, dam safety and water rights), and permits from the US Environmental Protection Agency (EPA) and US Forest Service (USFS). The county conservation districts provide permits to protect and preserve streams and rivers, whereas the road departments provide permits for access to conduct activities in road rights of way. Table 46 summaries the existing permits and their status for the Sibanye-Stillwater US PGM Operations. Mining occurs on Federal lands managed by the USFS and on private land. Most of the private land is historic patented mining claims which are now private. Those private lands not currently owned by Sibanye-Stillwater are leased. Federal lands and permission to access the surface for mining purposes is applied for and granted by the USFS in conjunction with the NEPA process and technical application to the USFS and DEQ. The Qualified Persons conclude that most of the key approvals have been granted 195 and are reasonably anticipated to continue to be granted for mining and processing operations for the foreseeable future. 19.2.4.2 Stillwater Mine and Hertzler Ranch Facilities Specific permitting requirements vary widely by agency and regulated media, and these are described in USFS and DEQ regulations and associated guidance. All necessary permits and approvals are in place and adequate for existing operations. Permits and licenses requiring renewal in FY2021 have been developed in a timely manner and submitted to the regulatory agencies for approval and efforts initiated for permits and licenses needing renewal in FY2022. Permits and approvals are tracked and renewal dates, schedules, timeframes and requirements for continued compliance are addressed in a timely manner with few exceptions. Reclamation bonding is required under the Operating Permit (No. 00118). Bonding is addressed in the Section 19.2.6 (Reclamation Plans and Costs). Permitting for planned expansions have been initiated in a timely manner and appear to be on track for schedule changes in operations. There are three current violations of the Operating Permit No. 00118 and two of the Exploration License No. 00046 relating to nitrate concentrations in groundwater and surface water, and submittal of Water Resource Management Reports (WRMR) and Biological Monitoring Reports beyond their prescribed deadlines. These violations were issued between December 2019 and February 2020. The December 2019 and February 2020 DEQ letters identified violations related to the following: • Stillwater (Operating Permit No. 00118) o Exceedances of nitrate+nitrite levels in East Side Waste Rock Storage Facility groundwater monitoring wells MW-14A and MW-18A (>10mg/l), which are located downgradient of the East Side Waste Rock Storage Facility and up-gradient of the Stillwater River. Elevated concentrations relate to seepage of meteoric waters through the East Side Waste Rock Storage Facility materials that accumulate nitrogen from traces of residual anfo; o Failing to submit a plan (or third-party review/report) for agency review and approval and falling to take prompt and appropriate remedial corrective measures to address the exceedance in HMW-10 at the Hertzler TSF; and o Failure to submit required 2018 Water Resource Monitoring Report and Biological Monitoring Reports by the June deadlines. o No new violations since February 2020. • Benbow (Exploration License No.00046) o Exceedances of nitrate+nitrite levels in BMW-3. Elevated concentrations relate to seepage of meteoric waters through the Benbow Waste Rock Storage Area materials that accumulate nitrogen from traces of residual anfo; and o Water Resource Monitoring Report was submitted six months after due date. Stillwater Mine initiated implementation of corrective actions at the East Side Waste Rock Storage Facility in 2016 with agency knowledge, although approved plans were not formally submitted or approved. Although water quality standards have been exceeded due to seepage from the East Side Waste Rock Storage Facility, no beneficial uses in the Stillwater River have been impacted or compromised with respect to surface water quality or residential groundwater supplies. DEQ has stated that the resolution of these violations will be dependent on the timely initiation of the meeting with DEQ
196 and USFS, the timely implementation of remedial corrective actions, and the submittal of documentation of the corrective actions specified in the Consolidated Operations and Reclamation Plan. Corrective actions at the East Side Waste Rock Storage Facility have been initiated since 2016 and include synoptic monitoring, phased East Side Waste Rock Storage Facility lining and Nitrogen Collection Pond installation, consultant evaluation of water quality changes (2018 and 2019) and initiation of in situ treatment of nitrogen with methanol injection. Corrective actions at the Hertzler TSF include repair of the liner tear (during 2015), installation of groundwater capture French drains and pump back system, installation of in-situ remediation, synoptic and biological monitoring on Stillwater River at Hertzler Ranch, and additional well installations. Corrective actions have been implemented at the Benbow Waste Rock Storage Facility and Benbow Mill Spring Creek. Corrective actions include synoptic monitoring of Benbow Mill Site Creek and Little Rocky Creek, installation of groundwater collection vaults for foundation drains (beneath waste rock storage area and WTP2 feed pond) and pump back of collected groundwater for treatment, as well as installation of a permeable reactive barrier (PRB) treatment system using methanol injection. Monitoring data indicates water quality concentrations in the creeks have returned to below regulatory levels, indicating successful implementation of the PRB, although groundwater concentrations remain above regulatory standards. The Qualified Persons conclude that the corrective actions implemented appear to have reasonable effectiveness and, where water quality has not yet been restored to below levels of regulatory concern, water quality concentration trends show stable to downward progression. Most of the violations have been resolved and closed while a few remain open at the time of the report. Closeout of the remaining violations is pending further monitoring and regulatory acceptance of corrective action completion. 19.2.4.3 East Boulder Mine Permits required for current operations at East Boulder Mine include permits from the State of Montana (e.g., mine permit, air quality permit, stormwater discharge permits, water discharge permits, exploration permit, and potable water supply permit), and permits from the Federal government including the EPA and USFS. There are no open regulatory violations at the time of compiling this Technical Report Summary. Federal permits from the EPA are for Class V groundwater injection wells. These Class V injection well permits address the following: • Recycling of water back into the mine (MT5000-05150); • Disposal of septic system water (MT50000-06439); • Disposal of treated adit water from the underground workings (MT50000-11713); and • Injection of methanol into shallow alluvial groundwater for in situ biological reduction of nitrates (MT50000-008511). An amendment to Operating Permit No. 00149 for a Stage 6 raise to the existing tailings storage facility has been completed and approvals are in place. However, approvals will be required for the development of the Lewis Gulch TSF and the Dry Creek WRSF, which will include a 404 Permit with the 197 US Army Corps of Engineers (ACOE) for the waste rock haulage crossing. The DEQ and USFS prepared an Environmental Assessment for the Stage 6 Tailings Storage Facility Expansion Project and the public comment period ended on June 15, 2020 and issued the final EA in September 2020. East Boulder Mine is approved to discharge from three outfalls into the East Boulder River and groundwater in an alluvial aquifer under MPDES Permit MR-0026808. A permitted injection well for treated mine water at the Yates Gravel Pit is permitted and infrastructure is in place but as of this review, the system has not yet been operated. Groundwater monitoring between 2005 and 2010 detected concentrations of nitrate as nitrogen greater than the non-degradation level established in the MPDES permit in three monitoring wells downgradient of the tailings storage facility and the infiltration pond. The DEQ found the mine out of compliance with the MPDES permit (MT0026808), triggering SMC (the owner at the time) and the DEQ to enter into an Administrative Order on Consent (Docket No., WQA-10-04). A compliance plan was submitted to DEQ and approved to establish a series of corrective actions to address the exceedance of the MPDES nitrate as nitrogen limits. In addition, a groundwater capture and pump back system was constructed and became operational in 2011. In situ treatment wells were installed and reagent was injected into injection wells to reduce nitrates as nitrogen concentrations. A TSF embankment underdrain system was also installed to collect meteoric water through the embankment rock fill and route the water back to the supernatant pond. An outer embankment liner was installed along the outer TSF Stage 3 slope to reduce infiltration of meteoric water through the embankment rock. As a result of the corrective actions, nitrate as nitrogen concentrations in downgradient monitoring wells were reduced to 35% of the non-degradation standard for groundwater in 2017. In 2017, the DEQ approved a mixing zone which resulted in a zone across which cumulative contributions from operational sources within the permit boundary are addressed. In January 2018, DEQ found that the Sibanye-Stillwater (SMC) is in compliance with the MPDES Permit and that the terms of the Consent Order were satisfied. The Qualified Persons conclude that long-term groundwater and surface water restoration and protection from operational impacts are ongoing and well managed, and compliance is likely to be achieved and maintained. 19.2.4.4 Columbus Metallurgical Complex The smelter at the Columbus Metallurgical Complex has only two permits, namely a Montana Air Quality Permit (#2635-17) from the DEQ Air Resources Bureau, and a MPDES Permit (-000469) with the DEQ Water Protection Bureau, both which are current and in good standing. The Qualified Persons understand that these permits are current and not due for renewal for several years. The Air Quality Permit (MAQP No. 2635-19) limits air emissions based on measured opacity, particulate emissions (PM10) from baghouse filters, and Sulphur dioxide (SO2) emissions based on maximum allowed smelter concentrate throughput (≤59 500 tons/year), precious metals recyclable material through put (≤15 000 tons/year), gypsum production (≤25 000 tons/rolling 12-month period), smelter slag production 198 (≤60 000 tons/rolling 12-month period), the amount of waste ore for lining the slag pits (≤40 000 tons/rolling 12-month period), and emergency back-up generator run time (≤500 hours/rolling 12-month period). Emissions testing requirements of the Air Permit include: • Particulate and opacity performance source tests every two years on the smelting circuit main stack and concentrate drying circuit main stack; • Particulate and opacity performance source tests every five years on the process baghouse for the nickel sulphate crystal dryer; and • SO2 performance source testing on the smelting circuit stack every five years. In addition, Continuous Emissions Monitoring System (CEMS) to monitor stack volumetric flow rate and record SO2 emissions are operated and maintained as required. Reporting of testing and monitoring results as well as material inventories is provided annually. The MPDES permit for stormwater contains non-numeric technology-based effluent limits and numeric water quality-based effluent limits. Non-numeric technology-based effluent limits include best management practices for managing materials to minimize contact with site waters, control site materials from egress, maintenance and erosion control practices. Numeric water quality-based effluent limits are established as well as benchmark and outfall monitoring requirements. However, the smelter operates in a zero-discharge mode with all stormwater contained onsite, following the storm water pollution prevention plan and best management practices with all storm water retained via use of berms, ditches and percolation ponds. All permits have been renewed or revised in a timely manner. There are no performance or reclamation bonds associated with this facility. 199 Table 46: Permits Status Summary for the Sibanye-Stillwater US PGM Operations Site Operating Permit and Type Status Permit Number Regulatory Agency Discharge Type Date Issued Renewal Date Description Stillwater Mine Original Permits Plan of Operations (POO) Active 118 USFS Custer Gallatin National Forest (CGNF)/ DEQ Hard Rock Mining Program Feb-1990 NA Plan of Operations Original (EIS) Record of Decision Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jan-1986 NA Mine Permit Operating Permit Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jan-1986 NA Operating Permit #00118 - Approved by ROD in December 1985 Stillwater Mine Amendments Operating Permit Amendment No. 1 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jun-1986 NA Plant site relocation Operating Permit Amendment No. 2 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Sep-1986 NA Sand borrow area approved Operating Permit Amendment No. 3 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jan-1987 NA Second sand borrow area approved Operating Permit Amendment No. 4 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Feb-1987 NA Nye Tailings Impoundment toe dike relocation Operating Permit Amendment No. 5 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Mar-1989 NA East-side development approved (increase permit area) Operating Permit Amendment No. 6 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jul-1989 NA Temporary sand pipeline approved Operating Permit Amendment No. 7 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Nov-1990 NA Adit relocated, 3 perc ponds added, 5 monitoring wells added Operating Permit Amendment No. 8 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Sep-1992 NA Facilities expansion, production increase to 2000 ton/day Operating Permit Amendment No. 9 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Mar-1996 NA East-West mining areas connected with haulage way (mining under Stillwater River) Operating Permit Amendment No. 10 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Nov-1998 NA Hertzler expansion approved and production cap eliminated
200 Site Operating Permit and Type Status Permit Number Regulatory Agency Discharge Type Date Issued Renewal Date Description Operating Permit Amendment No. 11 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Aug-1912 NA Revised Water Management Plan at Stillwater, Hertzler LAD (closure/post-closure), Boe Ranch LAD (operations/closure/post- closure) Operating Permit Amendment No. 12 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jul-2010 NA Addition of Hertzler LAD Pivot #7 Stillwater Mine Minor Revisions Operating Permit Minor Revision 89-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Dec-1989 NA Waste rock haulage railroad spur at 5150W Adit Operating Permit Minor Revision 90-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jul-1990 NA 5200E Ventilation Adit with auxiliary facilities Operating Permit Minor Revision 90-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Sep-1990 NA Sediment basin construction (no new permit area) Operating Permit Minor Revision 91-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jun-1991 NA 5200E Portal, spur road, laydown, and access road Operating Permit Minor Revision 91-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Oct-1991 NA Compressor pipeline crossing at Stillwater River Bridge Operating Permit Minor Revision 92-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Mar-1992 NA 5000E loci haul rail track extension Operating Permit Minor Revision 92-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program 1992 Permanent 5400E waste rock pile, eliminate laydown Operating Permit Minor Revision 93-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program 1993 NA 5300W ventilation improvements, 5400E rail haulage improvements Operating Permit Minor Revision 93-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Sep-1993 NA Compliance timeframe extension for Amendment 8 stipulations Operating Permit Minor Revision 93-003 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Oct-1993 NA 6500W secondary escape way installation Operating Permit Minor Revision 94-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Mar-1994 NA Expansion of OP boundary to include Stillwater Valley Ranch 201 Site Operating Permit and Type Status Permit Number Regulatory Agency Discharge Type Date Issued Renewal Date Description Operating Permit Minor Revision 94-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program May- 1994 NA Construction of west-side production shaft (location change) Operating Permit Minor Revision 94-003 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jul-1994 NA Tree planting to visually screen mine site facilities Operating Permit Minor Revision 94-004 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Nov-1994 NA Boulder storage area permitting in north area of permit boundary Operating Permit Minor Revision 95-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Mar-1995 NA Road relocation on Nye TSF embankment Operating Permit Minor Revision 95-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program 1995 NA Relocate west-side low grade ore stockpile to east-side Operating Permit Minor Revision 96-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Feb-1996 NA Waste rock processing to augment coarse tailings backfill Operating Permit Minor Revision 96-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Dec-1996 NA Smelter waste disposal (gypsum and slag) in Nye TSF Operating Permit Minor Revision 97-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jan-1997 NA Plan of Ops revision to construct Outfall 001 (not constructed) Operating Permit Minor Revision 97-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Aug-1997 NA Modify Nye TSF liner to lower final elevation (5111 to 5108) Operating Permit Minor Revision 97-003 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program 1998 NA Mine plan revision to extend 4400W level under the river Operating Permit Minor Revision 98-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jul-1998 NA Mine site facility additions (mill building, paste backfill plant, jaw crusher at west rail, covered conveyors from ore silo, service pipelines crossing river) Operating Permit Minor Revision 98-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Dec-1998 NA Mine site facility additions (maintenance dry & change house, office dry and change house, oil/drum storage, tire shop, water treatment plant addition) 202 Site Operating Permit and Type Status Permit Number Regulatory Agency Discharge Type Date Issued Renewal Date Description Operating Permit Minor Revision 99-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Sep-1999 NA Mine site facility additions (concrete sewage vault, filter press addition in concentrator) Operating Permit Minor Revision 99-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Aug-1999 NA Staged development plan for East-Side Waste Rock Storage Area Operating Permit Minor Revision 00-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Mar-2000 NA BTS expansion from 4 to 6 denitrification cells Operating Permit Minor Revision 00-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Mar-2000 NA Expansion of concentrator floatation circuit, installation of Larox Operating Permit Minor Revision 00-003 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program May- 2000 NA Hertzler pipeline route change (avoid culturally sensitive area) Operating Permit Minor Revision 00-004 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jul-2000 NA Dow Meadow Vent Raise (6500W) final location Operating Permit Minor Revision 01-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Mar-2001 NA 5000E compressed air line install, extension of rail on 5000W dump Operating Permit Minor Revision 01-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Sep-2001 NA Comprehensive mine site development plan (east and west side additions) Operating Permit Minor Revision 01-003 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Sep-2001 NA East-side compressor building addition Operating Permit Minor Revision 01-004 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Sep-2001 NA Warehouse addition (north-side of 5150W Paste Plant) Operating Permit Minor Revision 01-005 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Mar-2002 NA Two paste backfill lines to 4400W Operating Permit Minor Revision 01-006 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Mar-2002 NA East-side parking area for additional vehicles Operating Permit Minor Revision 03-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Apr-2003 NA Hertzler TSF Stage 2 final design and LAD storage pond Operating Permit Minor Revision 03-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jul-2003 NA Hertzler Ranch storm water system upgrades, lining west- side perc ponds, crusher operating area for Hertzler TSF 203 Site Operating Permit and Type Status Permit Number Regulatory Agency Discharge Type Date Issued Renewal Date Description construction, oil compressor building, LAD Pond expansion Operating Permit Minor Revision 04-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Apr-2004 NA Modifications to Hertzler Ranch TSF and LAD Pond liner Operating Permit Minor Revision 04-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Sep-2004 NA Soda ash silo installation, haul road on western edge of ESWRSF Operating Permit Minor Revision 04-003 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Dec-2004 NA Temporary reduction in Nye TSF freeboard Operating Permit Minor Revision 05-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Oct-2005 NA Advantex septic system upgrade, closure of MW-T3A Operating Permit Minor Revision 05-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Oct-2005 NA Hertzler Stage 2 underdrain building, Hertzler Pump House expansion, admin building expansion Operating Permit Minor Revision 06-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jan-2007 NA Construction of West Fork Stillwater River breakout Operating Permit Minor Revision 06-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program May- 2006 NA New surface sand line to 5500W Portal, parking lot access road, new washbay, Loci Shop restroom addition Operating Permit Minor Revision 06-003 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program May- 2006 NA Concentrator storage building (east-side of concentrator) Operating Permit Minor Revision 07-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jul-2007 NA Emergency Response Building, west-side portal overflow containment Operating Permit Minor Revision 07-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Apr-2009 NA Adjustment to flow monitoring requirement in Stillwater River Operating Permit Minor Revision 08-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Mar-2008 NA Relocation of laydown to north- side of delivery road Operating Permit Minor Revision 08-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program May- 2008 NA Tailings water treatment (150gal per minute) and land application
204 Site Operating Permit and Type Status Permit Number Regulatory Agency Discharge Type Date Issued Renewal Date Description Operating Permit Minor Revision 08-003 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Aug-2008 NA Reduction in Nye TSF freeboard (6ft to 5ft), employee survey discontinuance, upgrade of surface compressor line Operating Permit Minor Revision 08-004 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Nov-2008 NA Construction of parking lot entrance cover, 5150W mine water system upgrades Operating Permit Minor Revision 09-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Apr-2009 NA Land application of Hertzler TSF underdrain water, update Water Resources Monitoring Plan Operating Permit Minor Revision 09-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Feb-2010 NA Increase final elevation of ESWRSF from 5050 ft to 5150 ft Operating Permit Minor Revision 09-003 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Sep-2010 NA Hertzler TSF Stage 2 underdrain modification, relocate of Fire Water Pump House transformer, revisions to Water Resources Monitoring Plan Operating Permit Minor Revision 10-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Mar-2010 NA Hertzler in-situ methanol treatment injection wells Operating Permit Minor Revision 10-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jun-2010 NA Contaminated soils building, Stillwater Mining Company-16 enclosure, level access pad construction near pump house power line Operating Permit Minor Revision 10-003 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Oct-2010 NA Two 5400E vent raises near the 5400E Portal Operating Permit Minor Revision 10-004 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Nov-2010 NA Concentrator expansion (ceramic mills), water treatment cell 6 building addition Operating Permit Minor Revision 11-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Apr-2011 NA BASF pilot plant, oily dirt storage building Operating Permit Minor Revision 11-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jun-2011 NA Contaminated soils building, Stillwater Mining Company-16 205 Site Operating Permit and Type Status Permit Number Regulatory Agency Discharge Type Date Issued Renewal Date Description enclosure, level access pad construction near pump house power line Operating Permit Minor Revision 11-003 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jun-2011 NA Raise bore hole from 4400 level to 5000W Portal for road Operating Permit Minor Revision 11-004 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Nov-2011 NA Final design surface facilities for Blitz Project Operating Permit Minor Revision 12-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Apr-2012 NA Relocate power line, buried electrical line and transformer, office trailer installations, ESWRSF in-situ methanol treatment Operating Permit Minor Revision 12-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jun-2012 NA HDPE pipe welding shop addition at Batch Plant, concrete installations Operating Permit Minor Revision 12-003 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Sep-2012 NA Overhead process water line install, east-side storm water collection system, concrete pad Operating Permit Minor Revision 13-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Apr-2013 NA Inspection interval change to Hertzler HDPE line (5-yr to 10- year), expansion of Advantex waste water treatment pods by 3 Operating Permit Minor Revision 13-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jul-2013 NA New buried sandline from Hertzler Pump House to 5500W Portal, concrete retaining wall near propane tanks Operating Permit Minor Revision 13-003 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Dec-2013 NA Process water booster pump station, concrete pad for oxygen/acetylene, methanol storage tank and containment at Upper BTS, concrete pad for hazardous waste storage locker 206 Site Operating Permit and Type Status Permit Number Regulatory Agency Discharge Type Date Issued Renewal Date Description Operating Permit Minor Revision 14-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Mar-2014 NA LAD Pond expansion, Hertzler TSF Stage 3 construction plan Operating Permit Minor Revision 14-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jul-2014 NA Hertzler TSF Stage 3 construction plan modifications Operating Permit Minor Revision 14-003 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Nov-2014 NA Faulty mobile equipment building, concrete pads on 5000W rail, burial of overhead power lines, lower BTS building expansion for booster pump, concrete barrier walls at surface crusher, concrete storm water conveyance, additional east- side injection well Operating Permit Minor Revision 15-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Sep-2015 NA Concrete containment pad for biodiesel fuel tote storage Operating Permit Minor Revision 16-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jan-2016 NA Closure/Post-Closure monitoring locations (sites) Operating Permit Minor Revision 16-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jun-2016 NA ESWRSF lining system and water transfer system Operating Permit Minor Revision 16-003 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program May- 2015 NA Installation of inclinometers at the Nye and Hertzler TSFs Operating Permit Minor Revision 16-004 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Aug-2016 NA Concrete sidewalk to new Blitz trailer Operating Permit Minor Revision 17-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jun-2017 5900W Portal Slope Stabilization and Ground Control, Concrete Pad and Containment; (East Side Rail Dump Expansion removed from MR 5/17/2017) Operating Permit Minor Revision 17-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Aug-2017 Hertzler Ranch Perc Evaluation; Geotech work at West Fork (vent raise project); Geotech Evaluation upper Biological Treatment Cells; Add Admin Office Trailer 207 Site Operating Permit and Type Status Permit Number Regulatory Agency Discharge Type Date Issued Renewal Date Description Operating Permit Minor Revision 17-003 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Aug-2017 Expansion of the existing east- side rail dump area with wind break for two new dump bays, a rail spur and concrete fuel containment area Operating Permit Minor Revision 17-004 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Nov-2017 Installation of three supplemental monitoring wells at Hertzler Ranch near percolation ponds, expansion of the existing biological treatment system on the mine’s west site and installation of two water percolation ponds at the Hertzler Ranch site. Operating Permit Minor Revision 18-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Apr-2018 Authorization to discharge to Hertzler Ranch Percolation Ponds Operating Permit Minor Revision 18-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jun-2018 BTS Expansion; Mix Tanks for Reagent Additions at Surface Clarifiers; Surface Haul Truck Traffic Beacons; Transformer and Concrete Containment at Hertzler LAD Pond Operating Permit Minor Revision 18-003 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Aug-2018 Construction and operation of two ventilation raises from underground to surface (13.8 East and 13.8 West) Operating Permit Minor Revision 18-004 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Aug-2018 New East-Side Portal and Revised Rail Dump Expansion Operating Permit Minor Revision 18-005 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Oct-2018 Water Treatment Plant Screen/Filter House Operating Permit Minor Revision 19-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Mar-2019 Geotechnical Site Investigations Stillwater Mine and Hertzler Ranch; Change Nye TSF Cap Geotextile use
208 Site Operating Permit and Type Status Permit Number Regulatory Agency Discharge Type Date Issued Renewal Date Description Operating Permit Minor Revision 19-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jun-2019 Temp Off-Site Cathedral Mountain Ranch Laydown and Construction Yard Operating Permit Minor Revision 19-003 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jun-2019 Administration Building Expansion, Increased Septic Tankage Operating Permit Minor Revision 19-004 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jun-2019 Concentrate Handling Systems Improvements Operating Permit Minor Revision 19-005 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jun-2019 Production Shaft Hydrogeo Test Dewatering Well Operating Permit Minor Revision 19-006 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jan-2020 Compressor Building Addition, Light Vehicle Safety Access Roads, Concentrator Reagent Building Relocation Operating Permit Minor Revision 20-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Feb-2020 Modify the Stillwater Mine Concentrator 1) New Comminution Circuit Building, 2) New Electrical Substation, 3) Electrical pole re-routing Operating Permit Minor Revision 20-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program May- 2020 New Disc Filtration System and Building Operating Permit Minor Revision 20-003 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jun-2020 Minor Revision Acreage reconciliation: reconcile disturbed and permitted acreage in response to DEQ’s March 24 letter Operating Permit Minor Revision 20-004 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Jul-2020 Install two test wells and nested vibrating wire piezometers at Hertzler Ranch; in support of Stage 4/5 design Operating Permit Minor Revision 20-005 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Oct-20 NA Power Line and Miscellaneous Concrete Addition 209 Site Operating Permit and Type Status Permit Number Regulatory Agency Discharge Type Date Issued Renewal Date Description Operating Permit Minor Revision 21-001 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program July-21 NA Increased thickness of the waste rock cap on the Nye Tailings Storage Facility Operating Permit Minor Revision 21-002 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Sept-21 NA Installation of Test Wells Near the East Side Percolation Ponds Operating Permit Minor Revision 21-003 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Oct-21 NA Processing Support Structures and Miscellaneous Concrete Addition Operating Permit Minor Revision 21-004 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program July-21 NA Installation of Test Wells and Nested Vibrating Wire Piezometers at Hertzler Ranch Operating Permit Minor Revision 21-005 Active 118 USFS CGNF/ DEQ Hard Rock Mining Program Nov-21 NA Aquifer Test Discharge Plan Stillwater Mine Other Permits Treated Mine Water Discharge - Authorization to Discharge Under MPDES Active MT-0024716 DEQ Water Protection Bureau Groundwater or Surface Water Dec-2015 Sep-2023 Authorization to discharge treated mine water, under administrative extension until 9/2023 as permitting is completed MPDES Amendment In DEQ review MT-0024716 Groundwater or Surface Water Pending NA Request for additional time to complete improvements and additions (upgrades) to the water treatment systems, and once complete, to collect and evaluate post-stabilization system performance data Air Quality Permit - Preconstruction Permit Active 2459-19 Air Jun-2020 NA Temporary 500 Kw Tier-4 Gen Set, change to power for Mill Concentrator expansion Air Quality Permit - Title V Operating Permit Active OP2459-09 DEQ Air Resources Bureau Air July-2019 Nov-2023 Authorization to discharge air emissions for facilities emitting >100 tons per year 210 Site Operating Permit and Type Status Permit Number Regulatory Agency Discharge Type Date Issued Renewal Date Description Storm Water MPDES Permit Active MTR-000511 DEQ Water Protection Bureau Storm Water from site Oct-2019 Jan-2023 Multi-Sector General Permit for Storm Water Discharges Storm Water MPDES Permit Active MTR-000511 DEQ Water Protection Bureau Benbow Portal SWPPP; Addendum #2 August 2019 AQ Burn Permit TW40 Not Active TW40 DEQ Hard Rock Mining Program Air Excavation 404 Permit - Hertzler Pipeline Active NA Army Corp of Engineers Potable Water System Authorization - Beartooth Ranch Active PWSID MT0003972 DEQ Public Water & Subdivision Bureau NA 1998 NA Potable Water System Authorization - Stillwater Mine Active PWSID MT0003587 DEQ Public Water & Subdivision Bureau NA 1986 NA Potable Water System Authorization - Stratton Ranch Not Active/ Not Maintai ned PWSID MT0003588 DEQ Public Water & Subdivision Bureau NA NA Septic Drainfield - Septic System - Original system did not require permit Active NA DEQ Water Protection Bureau Groundwater 1986 NA Septic System - Onsite Wastewater Treatment System Active 05-Jun Stillwater County Groundwater Jan-2006 NA Septic System Modification Authorization - Septic Treatment System with land application Active EQ-06-1122 (see MR05- 001) DEQ Water Protection Bureau and Environmental Management Bureau Groundwater Oct-2005 NA Septic Drainfield - Septic System Modification Authorization - drainfield exp. Active ES94/B66 DEQ Water Protection Bureau NA 211 Site Operating Permit and Type Status Permit Number Regulatory Agency Discharge Type Date Issued Renewal Date Description Septic System - SVR Sewage Treatment System Permit Active 260 DEQ Water Protection Bureau NA Hazardous Waste Authorization/Classification Active MTD98155229 2 DEQ Waste and Underground Tank Management Bureau Jan-2000 NA Conditionally Exempt Small Generator / Upgrade to Small Quantity if generation exceeds 100kg/month UIC Class V Injection - Authorization by Rule Active #MT5000- 05134 USEPA Region 8 Groundwater Program Groundwater Nov-2001 NA Mine recycle water UIC Class V Injection - Authorization by Rule - Large Capacity Septic System Active #MT5000- 06454 USEPA Region 8 Groundwater Program Groundwater Mar-2005 NA (Septic System) Change in operating methods and conditions triggers EPA review and approval UIC Class V Injection - Authorization by Rule - Hertzler Methanol Injection Well Active #MT50000- 08681 USEPA Region 8 Groundwater Program Groundwater Dec-2009 NA Methanol injection well at Hertzler UIC Class V Injection - Authorization by Rule – Amendment - Mine Site Methanol Injection Wells Active #MT50000- 08681 USEPA Region 8 Groundwater Program Groundwater Jul-2012 NA Methanol injection wells downgradient of ESWRSF (five) UIC Class V Injection - Authorization by Rule – Amendment - Mine Site Methanol Injection Wells Active #MT50000- 08681 USEPA Region 8 Groundwater Program Groundwater Oct-2014 NA Methanol injection wells downgradient of ESWRSF (one additional well) State-wide Exploration Permit Active 46 DEQ Hard Rock and Placer Exploration/USFS May- 2016 May- 2022 Renewed annually, via letter 4/6/2021 Temporary Grazing or Livestock Use Permit Active NA USFS CGNF Aug-2021 Feb-2022 Renewed annually, renewed 2/28/2021; Ekwortzel/Kirch Agreement Encroachment Permit Active 2006-23 Stillwater County Encroachment Permit Active 2007-48 Stillwater County Encroachment Permit Active 2020-20 Jun-2020 NA Road Encroachment Permit Application, culverts for pipeline to pass under existing road
212 Site Operating Permit and Type Status Permit Number Regulatory Agency Discharge Type Date Issued Renewal Date Description USFS Special Use Permit - Stratton Ranch Road Active BEA407301 USFS CGNF Jan-2016 Dec-2016 Road Use Agreement USFS Special Use Permit - Delger Road Active BEA388 USFS CGNF Aug-12 Dec-2021 Road Use Agreement; in renewal process, extended by mutual agreement Stillwater Mine Licenses Nuclear Regulatory Commission - Materials License - Nuclear Density Gage Permit Active 25-26871-01 Nuclear Regulatory Commission Sep-2014 Nov-2023 Bureau of Alcohol Tobacco and Firearm – Explosives - Explosives Use and Storage Permit Active 9-MT-095-33- 7B-90263 Bureau of Alcohol Tobacco and Firearms Feb-2023 Radio Frequency Licenses - FCC Active 8610054645& 8802398055 Federal Communications Commission Stratton Man Camp License Active T-6732 Stillwater Mine Agreements Road Use/Maintenance Agreement (FAS419 & FR846) Active NA USFS CGNF Mar-1994 NA USFS Road Maintenance Agreement USFS Land Use Agreement Active AG-0355-B- 15-5501 USFS CGNF Apr-2015 Helibase Pad usage GNA 2009 Amendment Active Jan-2009 NA Good Neighbor Agreement East Boulder Original Permits Plan of Operations (POO) Active 149 USFS CGNF/ DEQ Hard Rock Mining Program Feb-1990 NA Plan of Operations Original (EIS) Record of Decision Active 149 USFS CGNF/ DEQ Hard Rock Mining Program Dec-1992 NA Mine Permit Operating Permit Active 149 USFS CGNF/ DEQ Hard Rock Mining Program Mar-1993 NA Operating Permit #00149 - Approved by ROD in 1993 following EIS East Boulder Amendments Amendment 001 to Operating Permit (EA) Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 1999 NA Water Management Plan Amendment (EA) 213 Site Operating Permit and Type Status Permit Number Regulatory Agency Discharge Type Date Issued Renewal Date Description Amendments 002 & 003 to Operating Permit (EIS) Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2012 NA Revised Water Management Plan + Boe Ranch LAD (EIS) East Boulder Minor Revisions Operating Permit Minor Revision 99-001 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 1999 NA Air Monitoring Site Operating Permit Minor Revision 00-001 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2000 NA Boe Ranch Pipeline Operating Permit Minor Revision 00-002 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2000 NA Tailings Pipeline Operating Permit Minor Revision 00-003 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2000 NA 6350 Explosives Bench laydown Operating Permit Minor Revision 01-001 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2001 NA Surface Crushing Facility Operating Permit Minor Revision 01-002 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2001 NA Slag Processing Operating Permit Minor Revision 01-003 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2001 Withdrawn Operating Permit Minor Revision 01-004 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2001 NA Temporary Buildings Operating Permit Minor Revision 04-001 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2004 NA Brownlee Vent Raise Operating Permit Minor Revision 04-002 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2004 NA Laydown Area 6 & Expansion of Soil Storage Operating Permit Minor Revision 04-003 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2004 NA LAD Area 6 Operating Permit Minor Revision 04-004 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2004 TSF - Detailed Design of Ongoing expansion Operating Permit Minor Revision 05-001 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2005 NA Warehouse Operating Permit Minor Revision 05-002 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2005 NA Water treatment improvements Operating Permit Minor Revision 06-001 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2006 NA TSF Wildlife Fence 214 Site Operating Permit and Type Status Permit Number Regulatory Agency Discharge Type Date Issued Renewal Date Description Operating Permit Minor Revision 06-002 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2006 NA Site Investigations Operating Permit Minor Revision 07-001 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2007 NA Event Pond Operating Permit Minor Revision 08-001 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2008 NA Native Borrow Excavation Operating Permit Minor Revision 08-002 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2008 NA New Oil Storage Building Operating Permit Minor Revision 09-001 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2009 NA EBMW-4 Replacement Well Operating Permit Minor Revision 09-002 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2009 NA Site Water Management Improvements Operating Permit Minor Revision 09-003 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2009 NA Reverse Osmosis Unit Operating Permit Minor Revision 09-004 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2009 NA In Situ Denitrification System Operating Permit Minor Revision 10-001 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2010 NA Drilling Investigation Operating Permit Minor Revision 10-002 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2010 NA Drilling Investigation Phase 2 Operating Permit Minor Revision 10-003 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2010 NA Surface Rail Improvements Operating Permit Minor Revision 10-004 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2010 NA Expansion of In-Situ Denitrification Operating Permit Minor Revision 11-001 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2011 NA Groundwater Capture System Operating Permit Minor Revision 12-001 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2012 NA Graham and Simpson Ventilation Raises Operating Permit Minor Revision 12-002 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2012 NA Truck Fall Arrest System Operating Permit Minor Revision 13-001 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2013 NA Modification to Simpson Creek Vent Raise Operating Permit Minor Revision 13-002 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2013 NA TSF Nitrogen Reduction 215 Site Operating Permit and Type Status Permit Number Regulatory Agency Discharge Type Date Issued Renewal Date Description Operating Permit Minor Revision 13-003 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2013 NA Used Oil Building Addition Operating Permit Minor Revision 13-004 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2013 NA GNA borehole drilling Operating Permit Minor Revision 14-001 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2014 NA Perc Pond Event Pond Modifications/Expansion Operating Permit Minor Revision 14-002 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2014 NA Borrow pit access road intersection realignments (2) Operating Permit Minor Revision 14-003 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2014 NA Two GNA Wells (EBMW-12 and EBMW-13) Operating Permit Minor Revision 14-004 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2014 NA Stage 3 TSF Slope Liner Design Change Operating Permit Minor Revision 15-001 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2015 NA Stage 3 TSF Slope Cover Final Design Operating Permit Minor Revision 15-002 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2015 NA New BO Parts Building Operating Permit Minor Revision 15-003 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2015 NA Geotechnical Test Holes Operating Permit Minor Revision 16-001 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2016 NA Water Resources Monitoring Plan Operating Permit Minor Revision 16-002 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2016 NA TSF Inclinometers Operating Permit Minor Revision 16-003 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2016 NA Revised Biological Monitoring Plan Operating Permit Minor Revision MR17-001 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2017 NA Groundwater Mixing Zone Operating Permit Minor Revision MR17-002 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2017 NA Site Security Gates Operating Permit Minor Revision MR18-001 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2018 NA Water Resources Monitoring Plan - no new disturbance Operating Permit Minor Revision MR18-002 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2018 NA Biological Monitoring Plan - no new disturbance Operating Permit Minor Revision MR18-003 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2018 NA Thickener and Portal Collection System
216 Site Operating Permit and Type Status Permit Number Regulatory Agency Discharge Type Date Issued Renewal Date Description Operating Permit Minor Revision MR18-004 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2018 NA Yates Deep Injection Test Well Operating Permit Minor Revision MR18-005 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2018 NA Geotechnical Drilling and Inclinometer Operating Permit Minor Revision MR19-001 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2019 NA Monitoring Well EBMW-12A Operating Permit Minor Revision MR19-002 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2019 NA Area 51 Borrow Design Changes - Operating Permit Minor Revision MR19-003 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2019 NA WTP Disk Filter System Operating Permit Minor Revision MR19-004 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2019 NA Concentrate Load-out Operating Permit Minor Revision MR19-005 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2019 NA Dry Fork Monitoring Wells Operating Permit Minor Revision MR20-001 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2020 NA Boe Ranch Deep Well Injection BRIW-1 Operating Permit Minor Revision MR20-002 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2021 NA Power Line Relocation - Southern Route 16.12 acres, 60 ft ROW Operating Permit Minor Revision MR20-003 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2020 NA Frog Pond Emergency Shelter Operating Permit Minor Revision MR20-004 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2020 NA Updates the Biological Monitoring Plan Operating Permit Minor Revision MR20-005 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2020 NA Concrete Aprons and Security Gate Operating Permit Minor Revision MR20-006 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2020 NA Bridge Geotechnical Drilling Operating Permit Minor Revision MR21-001 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2021 NA Construct Acid Storage Building/Injection Well Operating Permit Minor Revision MR21-002 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program Pending Stage 6 Monitoring Well Relocation Operating Permit Minor Revision MR21-003 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program 2021 NA Amendment 004 Dry Fork WRSA baseline monitoring wells 217 Site Operating Permit and Type Status Permit Number Regulatory Agency Discharge Type Date Issued Renewal Date Description Operating Permit Minor Revision MR21-004 Active 149 USFS CGNF/ DEQ Hard Rock Mining Program Pending Amendment 004 Portal Pump/Vault System and Mill Fuel Tank Relocation East Boulder Other Permits Authorization to Discharge Under MPDES Active MT-0026808 DEQ Water Protection Bureau Groundwater or Surface Water Nov-2015 Oct-2020 Application for Renewal was completed & submitted in Jan 05; DEQ administratively extended the permit until the application was processed and a new permit issued. Authorization to Discharge Under MPDES Active MT-0026808 DEQ Water Protection Bureau Groundwater or Surface Water Aug-2020 Oct-2020 Mixing Zone; DEQ administratively extended the permit until the application is processed and a new permit issued. Storm Water MPDES Permit Active MTR-000503 DEQ Water Protection Bureau Storm Water from site Feb-2018 Jan-2023 Multi-Sector General Permit for Storm Water Discharges Air Quality Permit Active MAQP 2563- 05 DEQ Air Resources Bureau Air Jul-2018 NA Air Permit update to increase production Public Water Supply Amendment 1 Active MT-0003894 DEQ Public Water & Subdivision Bureau Jan-2006 NA No expiration date changes in system trigger permit amendment. Warehouse and Dry expansion Septic Tank and Drain field - Septic Drain field Active EQ98/B50 DEQ Water Protection Bureau Groundwater Nov-1998 NA State of Montana Septic Tank and Sewage Treatment Plant - Septic Drain field Active 382 Sweet Grass County Groundwater Jan-1999 NA Sweet Grass County Permit Septic Tank and Drain field – Amendment - Septic Drain field Active EQ06-3314 DEQ Water Protection Bureau Groundwater Jan-2006 NA Warehouse and Dry expansion Hazardous Waste Authorization/Classification Active MTR- 000007823 DEQ Waste Management Bureau Jan-2000 NA Conditionally Exempt Small Generator / Upgrade to Small 218 Site Operating Permit and Type Status Permit Number Regulatory Agency Discharge Type Date Issued Renewal Date Description Quantity if generation exceeds 100kg/month UIC Class V Injection - Authorization by Rule Active #MT5000- 05150 USEPA Region 8 Groundwater Program Groundwater Apr-2002 NA Underground Mine Water UIC Class V Injection - Authorization by Rule – Amendment - Underground Mine Water Active #MT5000- 05150 USEPA Region 8 Groundwater Program Groundwater Jun-2002 NA (Underground Water) Change in operating methods and conditions triggers EPA review and approval UIC Class V Injection - Authorization by Rule - Septic System Active #MT50000- 06439 USEPA Region 8 Groundwater Program Groundwater Mar-2005 NA (Septic System) Change in operating methods and conditions triggers EPA review and approval UIC Class V Injection - Authorization by Rule - Methanol Injection Active #MT50000- 008511 USEPA Region 8 Groundwater Program Groundwater Sep-2009 NA Methanol Injection UIC Class V Injection - Authorization by Rule – Amendment - Methanol Injection Active #MT50000- 008511 USEPA Region 8 Groundwater Program Groundwater Jan-2011 NA Injection into additional 3 wells UIC Class V Injection - Authorization by Rule – Amendment - Underground Mine Water Active #MT50000- 11713 USEPA Region 8 Groundwater Program Groundwater Sep-2018 NA Disposal of treated adit water from the underground mine. Road Agreement Active NA USFS Fire Management Division CGNF Road Right of Way Active NA USFS Fire Management Division CGNF State Trade Waste Burn Permit - Air Quality Burn Permit Active TW459 DEQ Air Resources Bureau Air Sep-2019 Sep-2022 Renew Annually Forest Service Burn Permit - Burn Permit Active NA USFS Fire Management Division CGNF Air As Needed As Needed Required for individual burns between May 1 and October 15; apply as needed Yates Gravel Pit - Amendment 3 - Open Cut Gravel Active 1702 DEQ Industrial & Energy Minerals Bureau Feb-2020 Oct-2027 Extended reclamation date of the permit through 2027 219 Site Operating Permit and Type Status Permit Number Regulatory Agency Discharge Type Date Issued Renewal Date Description East Boulder Licenses State-wide Exploration License Active 46 DEQ Hard Rock and Placer Exploration/USFS May- 2020 May- 2022 Renewed Annually Nuclear Regulatory Commission - Materials License - Nuclear Density Gage Permit Active 25-26871-01 Nuclear Regulatory Commission Sep-2014 Nov-2023 Bureau of Alcohol Tobacco and Firearm - Explosives Active 9-MT-095-33- 7B-90263 Bureau of Alcohol Tobacco and Firearms Feb-2023 East Boulder Agreements FDR 205 and FDR 6644 Road Maintenance Agreement Active USFS CGNF/DEQ Hard Rock Mining Program Aug-1996 NA USFS Road Maintenance Agreement Snotel Active No. 65-0325- 14-001 NRCS - National Resource Conservation Service Jan-2017 USDA - Annual Renewal, funded by SSW through 2017 State Lands Lease Active DNRC Trust Land Management Division Mar-2016 Mar-2023 GNA 2009 Amendment Active Jan-2009 NA Good Neighbor Agreement Boe Ranch Grazing Lease - Private party lease Active Mar-2016 Mar-2017 Metallurgic al Complex Original Permits Air Quality Permit - Air Quality Permit Active 2635-17 DEQ Air Resources Bureau Air Oct-2012 NA Covers Smelter, BMR, and Laboratory Storm Water MPDES Permit - Storm Water Discharge Permit Active MTR-000469 DEQ Water Protection Bureau Storm Water from site Dec-2013 Jan-2023 Multi-Sector General Permit for Storm Water Discharges
220 Requirements for Environmental Monitoring, Closure and Post Closure, and Management Plans 19.2.5.1 Stillwater Mine and Hertzler Ranch Facilities Operational management, reclamation and monitoring of wastes and reclamation of waste management facilities are addressed in the current Consolidated Operations and Reclamation Plan as well as the Operating Permit 00118. In addition, waste management facilities are described in Section 17.1. Mine waste solids are managed in the TSFs, which include the Hertzler TSF and the Nye TSF. In addition, waste rock at the Stillwater Mine is managed in waste rock storage areas, which include the East Side Waste Rock Storage Facility (ESWRSF) and the Benbow Portal waste rock storage area. Mine liquid wastes at Stillwater Mine include mine adit water, process water, waste rock storage area infiltration water and potable water supplies. Water collected underground (natural groundwater, recycled mining water, and mine decant water from the mine backfill slurry) is pumped to the surface where it undergoes settling in clarifiers and may be stored in surface recycle water storage tanks. Recycle water is returned for reuse underground in the mining process. Excess water not recycled for mining is routed to the West-Side Biological Treatment System/Moving Bed Bioreactor (BTS/MBBR) prior to disposal. Potable water is supplied by two water wells, namely West Well 1 (PW-W) and East Well 2 (PW-E). Water from infiltration of meteoric water through the ESWRSF is managed through a nitrate capture system (NCS) that is constructed of (from top to bottom) a 12-inch-thick drain-rock layer, a geo- composite drainage layer, and textured both sides 60-mil to 80-mil high-density polyethylene (HDPE) geomembrane liner. Nitrogen-containing meteoric waters intercepted by the drain layer and membrane liner are conveyed to an exterior collection pond. The NCS water may be routed for recycle use underground or transferred to the BTS/MBBR. Smelter slag is processed at the Stillwater Concentrator on a campaign basis. Slag is hauled in containers separate from the concentrate and stockpiled near the 5000E Portal. When sufficient slag (approximately 2 500 tons) accumulates, RoM ore processing stops thus paving the way for the processing of slag, usually on a 24-hour campaign. Smelter slag is treated by the same beneficiation process that is used for ore. Spent material from the slag that is reprocessed through the concentrator reports to the lined tailings impoundment or as backfill in the underground mine. The volume of reprocessed spent material has historically been an insignificant percentage of the total material processed at the Stillwater concentrator. Smelter slag may also be processed at the East Boulder Concentrator under the EBPO/OP MR01-001. Operational monitoring programs include air quality, surface water, groundwater, injection wells, adit water, storm water, biological conditions, tailings storage facility monitoring, and monitoring of water treatment systems. This monitoring is documented in actionable reports identified in Table 47. 221 Table 47: Stillwater Mine Operations Actionable Reportable Documents Required Submittals -Operations Required Basis Frequency Format Due Date(1) Air Resources: Air Quality Monitoring Report Montana Air Quality Permit No. OP2459-07 Semi- Annual Electronic 15-Feb Air Quality Emissions Inventory Report Montana Air Quality Permit No. MAQP No. 2459-18 Annual Electronic 15-Feb Water Quality and Quantity: MPDES Discharge Monitoring Reporting Montana Pollutant Discharge Elimination System Permit (MPDES) No. MT0024716 Monthly Electronic DMR 28th of following month Quarterly 28th of month following end of Q1, Q2, Q3, and Q4 Stillwater Mine MPDES Storm Water Report Multi-Sector General Permit for Storm Water Discharges Associated with Industrial Activity No. MTR000511 Quarterly Electronic DMR 28th of month following end of Q1, Q2, Q3, and Q4 Water Resources Monitoring Report 1992 Final EIS and ROD Stillwater Expansion (2000 Tons Per Day) 2018 Water Resources Monitoring Plan (WRMP) Annual Electronic 30-Jun Water Quality and Quantity; Wildlife/Aquatic Resources: Biological Monitoring Report 1992 Final EIS and ROD Stillwater Expansion (2000 Tons per Day) Biological Monitoring Plan Annual Electronic 31-May Chlorophyll-a Periphyton and Macroinvertebrates 2nd year Electronic 31-May (respective years only) Geochemistry: Adit Water Quality Report in Annual Water Resources Monitoring Report Operating Permit (OP) No. 00118 2018 Water Resources Monitoring Plan (WRMP) Annual Electronic 30-Jun Waste Rock and Tailings Characterization in OP Annual Progress Report 1992 Final EIS and ROD Stillwater Expansion (2000 Tons per Day) Annual Electronic 28-Feb Mining Plan: OP Annual Progress Report OP No. 00118 Annual Electronic Submitted by Engineer of Record 120 days after conducting annual Tailings Storage Facility (TSF) Tailings Operations, Maintenance and Surveillance Inspection Report 82-4-336 MCA 2014 2012 Final EIS Revised Water Management Plan 2012 ROD Revised Water Management Plan Annual Nye and Hertzler TSF Supernatant Volume and Tailings Grade Nye and Hertzler Tailing Storage Facility Structural Integrity and Function Annual Nye and Hertzler Tailings density 5-year Hertzler TSF Underdrain in Annual Water Resources Monitoring Report Annual 30-Jun Consolidated Operations Reclamation Plan Annual 01-Jul Federal Reporting Requirements: Injection Well Monitoring Stillwater Mine Remediation Wells Authorization by rule Electronic Upon changes to injection program and as requested by EPA Toxic Release Inventory Report U.S. Environmental Protection Agency (EPA) Emergency Annual Electronic 01-Jul 222 Required Submittals -Operations Required Basis Frequency Format Due Date(1) Planning and Community Right to Know Act Note (1) Q refers to quarter and Q1 refers to first quarter, etc. Note: DEQ= MT Department of Environmental Quality; MAQP=MT Air Quality Permit; AQB=Air Quality Bureau; WPB=Water Protection Bureau; EIS= Environmental Impact Statement; ROD=Record of Decision; DMR=Discharge Monitoring Report; MCA=Montana Code Annotated; EIS=Environmental Impact Statement; ROD=Record of Decision; TSF=Tailings Storage Facility Water management and treatment methods include water recycling in the mining process, clarification, biological treatment for nitrate, filtration, stormwater management, and discharge to the ground surface by land application disposal or percolation in infiltration ponds. Water quality impacts that can be attributed to Stillwater Mine operations from 1981 to 2021 are limited to increased nitrate and total dissolved solids levels in groundwater beneath the Stillwater Mine, Hertzler Ranch site, and Benbow waste rock storage area. As a result of in situ groundwater denitrification, increases in iron, nickel, and manganese have been detected in a couple of downgradient monitoring wells from changing redox conditions. The conditions are corrected when denitrifications activities are discontinued. No other constituents of concern have been identified during water quality monitoring and through numerous environmental reviews and analyses. Groundwater monitoring at the Stillwater Mine and associated facilities is performed per the Water Resource Management Plan as a condition of the Stillwater Mine Plan of Operations as documented in the Consolidated Operations and Reclamation Plan. The Water Resource Management Plan contains a comprehensive listing of all required water quality monitoring for the Stillwater Mine, Stratton Ranch and Hertzler Ranch. In total, the Water Resource Management Plan, describes requirements for groundwater monitoring at 38 sites, which include 21 monitoring wells at the mine site, 14 monitoring wells at the Hertzler Ranch and three monitoring wells at the Stratton Ranch. Closure monitoring is documented in actionable reports identified in Table 48 while post-closure monitoring is documented in actionable reports in Table 49. The Stillwater Mine Reclamation Plan incorporates the measures analysed and approved under the 2012 Record of Decision (DEQ and USFS, 2012a). The reclamation plan for the Benbow Portal was developed as a separate document but is now included in the annual update to the Consolidated Operations and Reclamation Plan. All surface disturbances within the permit boundary will be reclaimed, where required. Underground mine closure, closure of facilities at Stillwater Mine and Hertzler Ranch, and water management at closure are described in the plan. Final reclamation will take place after mine operations have ceased for portions not otherwise reclaimed concurrently during operations. Table 48: Stillwater Mine Closure Actionable Reportable Documents Required Reporting—Closure (Years 1-3) Requirement Basis Frequency Format Due Date Water Quality and Quantity: Water Resources Monitoring Report Groundwater and Surface Water monitoring occurs seasonally (three times per year) 2012 ROD; OP 00118 WRMP Annual Electronic Year 1: 60 days past Q4 of closure Years 2 and 3: anniversary of initial report Adit Water Monitoring Monitoring occurs monthly until discharged underground 2012 ROD Annual Electronic 223 Required Reporting—Closure (Years 1-3) Requirement Basis Frequency Format Due Date Hertzler TSF Underdrain, Hertzler Ranch TSF Cover Seepage, and Stillwater TSF Cover Seepage Monitoring occurs seasonally until quality stabilizes 2012 ROD Annual Electronic Shaft Water Quality and Level/Elevation Monitoring Monitoring occurs seasonally for quality and level until stabilization, then annual frequency 2012 ROD Annual Electronic Hertzler Ranch Land Application Disposal System Annual monitoring for salts load from land application system during closure 2012 ROD Annual Electronic Reclamation Plan; Geotechnical and Stability: Tailings Storage Facility (TSF): Stillwater TSF Structural Integrity and Function Annual inspection by Engineer of Record, maintenance as needed 2012 ROD 2012 Final EIS Revised Water Management Plan Annual Electronic Year 1: 60 days past Q4 of closure Years 2 and 3: anniversary of initial report Stillwater TSF Seepage Outlet Structure and Shaft Trout Stream Channel Annual inspection, maintenance as needed Hertzler Ranch TSF Structural Integrity and Function Annual inspection, maintenance as needed Annual Electronic Reclamation Plan; Geotechnical and Stability: Hertzler Seepage Outlet Structure and Discharge Channel to LAD Pond Annual inspection, maintenance as needed 2012 Final EIS 2012 ROD Revised Water Management Plan Annual Electronic Year 1: 60 days past Q4 of closure Years 2 and 3: anniversary of initial report Stillwater Mine Storm Water Channels Annual inspection, maintenance as needed Annual Electronic Table 49: Stillwater Mine Post Closure Actionable Reportable Documents Required Reporting—Post Closure (Years 4-8) Requirement Basis Frequency Format Due Date Reclamation Plan; Water Quality and Quantity: Water Monitoring Report Groundwater and Surface Water monitoring occurs seasonally (three times per year) 2012 ROD Revised Water Management Plan; OP 00118 WRMP Annual Electronic Years 4 through 8: annual anniversary of initial closure report Shaft Water Quality and Level/Elevation Monitoring occurs seasonally for quality and level until stabilization, then annually until it discharges Annual Hard Copy Report Years 4 through 8: annual anniversary of initial closure report Reclamation Plan; Geotechnical and Stability: Hertzler and Stillwater TSF Structural Integrity and Function; Annual visual monitoring Years 4 and 5 2012 Final EIS and ROD Annual Hard Copy Report Years 4 through 8: annual anniversary of initial closure report Visual monitoring every 5 years from Year 5 until final bond release 5-Year Electronic Fifth-year anniversaries of Year 5 closure report Stillwater TSF Seepage Outlet Structure and Shaft Discharge Trout Stream, Hertzler TSF Cover Seepage Discharge Channel, Storm Water Channel Monitoring annually Years 4 - 8 Annual Electronic Years 4 through 8: annual anniversary of initial closure report Monitoring every 5 years from Year 5 until final bond release 5-Year Electronic Fifth-year anniversaries of Year 5 closure report Site Maintenance Monitoring:
224 Required Reporting—Post Closure (Years 4-8) Requirement Basis Frequency Format Due Date Function of facilities Ponds (percolation and Hertzler LAD storage) Storm water ditches and sediment basins TSF seepage and Shaft outlet channels TSF covers and underdrain outlet structures 2012 Final EIS Revised Water Management Plan 2012 FMEA Annual Electronic Years 4 through 8: annual anniversary of initial closure report Abandon/Close Monitoring Wells Abandonment anticipated to be in Year 9 Year 9: anniversary of initial closure report Vent raise replacement 2012 USFS 2012 FMEA Year 63 Note: FMEA=Failure Modes and Effects Analysis; ROD=Record of Decision; WRMP=Water Resources Monitoring Plan Concurrent reclamation has occurred since the start of operations in 1986. At the time of mine closure and facilities reclamation, all surface facilities will be decommissioned, all structures will be disassembled and removed from the site, and the land reclaimed consistent with the approved post-mine land use. Roads that will remain will include the main access road to the reclaimed portals, tailings storage facilities, water conveyance structures, and water monitoring sites to allow for long-term monitoring and maintenance. These roads will be reclaimed when long-term monitoring and maintenance activities cease. The Qualified Persons conclude that adequate volumes of soil materials are available for replacement of the required soil cover on all disturbances. Furthermore, reclamation should meet the State of Montana provisions and requirements under the Montana Metal Mine Reclamation Act (MCA 82-4-336). The Stillwater Mine Closure and Reclamation Plan is also intended to meet the USFS requirements governing mineral development (36 CFR 228.8), and reclamation requirements under the Federal Seed Act (7 U.S.C., Section 1551-1610) and current USFS seeding guidelines. 19.2.5.2 East Boulder Mine East Boulder Mine consists of the underground mine and surface processing, waste rock and tailings storage facilities. The Consolidated Operations and Reclamation Plan describes water management of both underground mine water, supernatant water from the tailings storage facility, and basin and embankment underdrain water. Operational management, reclamation and monitoring of wastes and reclamation of waste management facilities are addressed in the current Consolidated Operations and Reclamation Plan for East Boulder Mine. East Boulder Mine has several plans including those for water resource and biological monitoring and resource protection. Operational monitoring programs include air quality, surface water, groundwater, injection wells, adit water, storm water, biological conditions, TSF, and water treatment systems. This monitoring is documented in actionable reports identified in Table 50. Waste management facilities are described in Section 17.2. Mine waste solids are managed in the East Boulder TSF. Waste rock from the underground mine is currently used in construction of the TSF embankments. The finest fraction of the tailings is pumped to the lined tailings facility. Currently Stages 3 and 4 are constructed while Stages 5 and 6 are permitted for development. Supernatant water from the TSF is recycled in a closed loop system with the mill. The TSF basin capture water is pumped to either 225 the TSF supernatant pond or the water recycle pond. The embankment underdrain capture water is pumped to the TSF supernatant pond. Water collected underground (natural groundwater, recycled mining water, and mine decant water from the slurry of mine backfill) is discharged from the mine adit, collected, treated in the treatment plant, and then returned for reuse underground in the mining process or discharged via the approved MPDES Permit. Water management and treatment methods include water recycling in the mining process, biological treatment for nitrate, stormwater management, and discharge to the groundwater by percolation in infiltration ponds. East Boulder Mine recently received approval to dispose of water in a deep injection well on Boe Ranch, although this system has not yet been placed into service. The Water Resources Monitoring Plan, updated in August 2021, is a reference document for all water quality monitoring for the Plan of Operations, the Operating Permit No. 00149 and the MPDES Permit MT0026808. The plan outlines the approved monitoring locations, schedule, list of parameters for analysis, and methods for sampling of surface water, mine water, and groundwater at East Boulder Mine. Monitoring requirements for the Boe Ranch LAD facility are included in the Water Resources Monitoring Plan and include sampling of springs and groundwater and surface water locations as required by the EIS and the Record of Decision but will only become active if the land application disposal facility is constructed. Table 50: East Boulder Mine Operations Actionable Reportable Documents Required Submittals - Operations Required Basis Frequency Format Due Date(1) Air Resources: Air Quality Monitoring Report Montana Air Quality Permit No. 2563-05 Annual Hard Copy 15-Feb Air Quality Emissions Inventory Report Montana Air Quality Permit No. 2563-05 Annual Electronic 15-Feb Water Quality and Quantity: MPDES Discharge Monitoring Reporting Montana Pollutant Discharge Elimination System Permit (MPDES) No. MT0026808 Monthly Electronic DMR 28th of following month Quarterly 28th of month following end of Q1, Q2, Q3, and Q4 Annual 28th of month following end of Q4 MPDES Storm Water Report Multi-Sector General Permit for Storm Water Discharges Associated with Industrial Activity No. MTR000503 Quarterly Electronic DMR 28th of month following end of Q1, Q2, Q3, and Q4 Water Monitoring Report 1992 Final EIS and ROD Water Resources Monitoring Plan (WRMP) Quarterly with Annual Summary Hard Copy 60 days past end of Q1, Q2, Q3, and Q4 and Annual Summary February Water Quality and Quantity; Wildlife/Aquatic Resources: Biological Monitoring Report Biological Monitoring Plan Annual Hard Copy 30-April Chlorophyll-a Periphyton and Macroinvertebrates 3rd-year Hard Copy 30-April (respective years only) 226 Required Submittals - Operations Required Basis Frequency Format Due Date(1) Geochemistry: Adit Water Quality Report Quarterly Monitoring Operating Permit No. 00149 Quarterly with Annual Summary Hard Copy 60 days past end of Q1, Q2, Q3, and Q4 Waste Rock and Tailings Characterization 1992 Final EIS and ROD Quarterly with Annual Summary Hard Copy 60 days past end of Q1, Q2, Q3, and Q4 and Annual Summary February Mining Plan: MMRA Operating Permit Annual Report Operating Permit No. 00149 Annual Hard Copy 26-May Tailings Storage Facility (TSF) Tailings Operations, Maintenance and Surveillance Inspection Report 82-4-336 MCA 2014 2012 Final EIS Revised Water Management Plan 2012 ROD Revised Water Management Plan Annual Tailings Supernatant Volume and Tailings Grade Impoundment Structural Integrity and Function Annual Tailings Density 5-year Tailings Impoundment Underdrain Monitoring occurs quarterly Annual 30-Jun Consolidated Operations Reclamation Plan Annual 01-Jul Federal Reporting Requirements: Toxic Release Inventory Report U.S. Environmental Protection Agency (EPA) Emergency Planning and Community Right to Know Act Annual Electronic 01-Jul Federal Reporting Requirements: Toxic Release Inventory Report U.S. Environmental Protection Agency (EPA) Emergency Planning and Community Right to Know Act Annual Electronic 01-Jul Federal Reporting Requirements: Toxic Release Inventory Report U.S. Environmental Protection Agency (EPA) Emergency Planning and Community Right to Know Act Annual Electronic 01-Jul (1) Q refers to quarter, Q1 refers to first quarter, etc. Note: DEQ= MT Department of Environmental Quality; MAQP=MT Air Quality Permit; AQB=Air Quality Bureau; WPB=Water Protection Bureau; EIS= Environmental Impact Statement; ROD=Record of Decision; DMR=Discharge Monitoring Report; MCA=Montana Code Annotated; EIS=Environmental Impact Statement; ROD=Record of Decision; TSF=Tailings Storage Facility The Qualified Persons can confirm that closure monitoring is documented in actionable reports identified in Table 51 while post-closure monitoring is documented in actionable reports listed in Table 52. All surface disturbances within the permit boundary will be reclaimed, where required. Underground mine closure, closure of facilities, and water management at closure are described in the Consolidated Operations and Reclamation Plan, which addresses closure and post-closure monitoring. Final reclamation will take place after mine operations have ceased for portions not otherwise reclaimed concurrently during operations. 227 Table 51: East Boulder Mine Closure Actionable Reportable Documents Required Reporting—Closure (Years 1-3) Requirement Basis Frequency Format Due Date Water Quality and Quantity: Water Resources Monitoring Report Monitoring occurs quarterly 2012 ROD; Revised Water Management Plan; Operating Permit 00149 Surface and Groundwater Monitoring Plan Annual Hard Copy Year 1: 60 days past Q4 of closure Years 2 and 3: annual anniversary of initial report Adit Water Monitoring Monitoring occurs tri-annually: spring, summer, fall 2012 ROD; Revised Water Management Plan Annual Hard Copy Reclamation Plan; Geotechnical and Stability: Tailings Storage Facility: Impoundment Underdrain Monitoring occurs quarterly 2012 ROD 2012 Final EIS Revised Water Management Plan Annual Hard Copy Year 1: 60 days past Q4 of closure Years 2 and 3: annual anniversary of initial report Tailings Impoundment Cover Seepage Monitoring occurs quarterly Tailings Density, Grade, Supernatant Volume Impoundment Structural Integrity and Function Visual monitoring occurs annually Annual Hard Copy Table 52: East Boulder Mine Post Closure Actionable Reportable Documents Required Reporting—Post Closure (Years 4-8) Requirement Basis Frequency Format Due Date Reclamation Plan; Water Quality and Quantity: Water Monitoring Report Monitoring occurs quarterly 2012 ROD; Revised Water Management Plan; Operating Permit 00149 Surface and Groundwater Monitoring Plan Annual Hard Copy Report Years 4 through 8: annual anniversary of initial closure report Adit Water Monitoring Monitoring occurs bi-annually 2012 ROD; Revised Water Management Plan Annual Hard Copy Report Years 4 through 8: annual anniversary of initial closure report Reclamation Plan; Geotechnical and Stability: Tailings Storage Facility Impoundment Structural Integrity and Function. Annual visual monitoring Years 4 and 5 2012 Final EIS and ROD; Revised Water Management Plan Annual Hard Copy Report Years 4 through 8: annual anniversary of initial closure report Tailings Storage Facility Visual monitoring until final bond release 5-Year Hard Copy Report Fifth-year anniversaries of Year 5 closure report Tailings Storage Facility Seepage Outlet Structure, Cover Seepage Discharge Channel, Storm Water Channel Monitoring annually Years 4 - 8 Annual Hard Copy Report Years 4 through 8: annual anniversary of initial closure report Tailings Storage Facility Monitoring every 5 years from Year 5 until final bond release 5-Year Hard Copy Report Fifth-year anniversaries of Year 8 closure report Site Maintenance Monitoring:
228 Required Reporting—Post Closure (Years 4-8) Requirement Basis Frequency Format Due Date Function of facilities Ponds Storm water ditches and basins Tailings Storage Facility seepage outlet channels Tailings Storage Facility cover and underdrain outlet structure 2012 Final EIS Revised Water Management Plan 2012 FMEA Annual Hard Copy Report Years 4 through 8: annual anniversary of initial closure report Vent raise replacement 2012 USFS Report Year 63 from closure Note: FMEA=Failure Modes and Effects Analysis; ROD=Record of Decision; WRMP=Water Resources Monitoring Plan 19.2.5.3 Columbus Metallurgical Complex Waste management facilities at the Columbus Metallurgical Complex include temporary gypsum and smelter slag storage and storm water management. Air emissions are managed and monitored per the 2019 air permit requirements and include bag house collection of particulates and SO2 scrubbing systems. Air monitoring includes measurement of opacity, particulate emissions (PM10 and PM2.5), CO, VOC and SO2 emissions, and effluent flow rates. The air permit was updated in 2019 to encompass planned increases in production and refining. SMC (Sibanye-Stillwater) was given approval for the processing of smelter slag at Stillwater and East Boulder Mines to recover additional precious metals. Slag from the smelter is trucked to the mines daily for batch processing. Slag is also crushed in campaigns and used as slag pit liner material. A quarterly sample is collected and analysed for leachability (TCLP); testing to date confirms the slag passes TCLP criteria as non-hazardous. The slag is temporarily stored on the East Property located southeast of the smelter and in the slag bunkers located north of the smelter pending transport to the mines. Excess gypsum is stored on site in lined bunkers and shipped offsite for either agricultural use as fertilizer or directly to approved sanitary landfills in Billings or Hardin, Montana. The smelter is considered by the EPA to be a large quantity generator of hazardous wastes that include the following sources: • Laboratory nickel/copper/arsenic/chromium acidic solutions; • Slag, crucibles, and cupels from fire assay contaminated with lead and other metals (e.g., barium, cobalt, chromium, copper, lead, manganese, mercury, nickel and zinc); • Contaminated personal protective equipment; • Waste potassium permanganate; • Iron removal residue solids containing arsenic, cadmium, chromium and lead; • Electrowinning filter cake material contains arsenic; • Electrowinning filter cloth containing lead; • Fluorescent bulbs; • Methyl ethyl ketone contaminated rags; and • Spent aerosol paint canisters. All hazardous wastes are shipped offsite for proper disposal at a permitted, out-of-state Treatment Storage Disposal Facility. The Qualified Persons are of the view that there are no closure or post closure monitoring requirements for this facility. 229 Reclamation Plans and Costs 19.2.6.1 Overview Reclamation plans and bond amounts are available for Stillwater and East Boulder Mines in their respective Consolidated Operations and Reclamation Plan. The Benbow Portal has an independent Plan of Operations, Reclamation Plans, and accompanying reclamation bond that are separate from the Stillwater Mine Plan of Operations and Operating Permit. The current State bonding is the principal financial instrument covering reclamation and restoration obligations. Reclamation surety bond amounts have been developed using methods provided in the DEQ Bonding Procedures Manual (DEQ, 2001). Reclamation surety bonds run to the benefit of the State of Montana, which issues the Operating Permits, and not to the Federal Government. Direct reclamation costs include, but are not limited to, tailings impoundments; waste rock storage facilities; portals, roads, and diversions interim care and maintenance; closure water treatment; and long-term care and maintenance. Indirect reclamation costs are based on a fixed percentage of direct costs (excluding long-term care and maintenance). Reclamation costs have been developed for forward looking five- year periods with an assumed annual inflation rate of approximately 2%. 19.2.6.2 Stillwater Mine and Hertzler Ranch Facilities Mine closure plans and bond bases of estimate are provided for the Stillwater Mine facilities in the Consolidated Operations and Reclamation Plan, the Benbow Portal reclamation plan and bond bases of estimate are separate. Reclamation for these facilities includes closure and post-closure management of adit waters, tailings storage facility, waste rock storage area, storm water management, and post-closure monitoring and maintenance programs. Post-closure monitoring would address the following items until bond is released and all applicable water quality standards are met: • Groundwater and surface water quality would be monitored three times per year according to the approved water quality monitoring plans and the MPDES permit in place during post- closure; • Shaft water quality would be monitored three times per year and annually thereafter until water quality stabilizes and mine water discharges from the shaft; • Shaft water levels would be monitored three times per year until mine water exits the shaft; • Tailings impoundment function and structural integrity would be monitored annually for the first five years and then once every five years thereafter; • Seepage outlet structures and discharge channel function would be monitored annually for the first five years and then once every five years thereafter; • Hertzler Ranch surface and groundwater monitoring would occur three times per year for nutrients, salts, and biomonitoring; • Water from the Hertzler Ranch tailings storage facility seepage outlet structure would be monitored for quality and flow rate three times per year until water quality stabilizes; • The post-closure maintenance plan would include the following items to be conducted annually during the first five years of closure and once every five years thereafter until bond is released, the MPDES permit is no longer needed, and water quality standards in effect at that time are met: 230 o Function of all ponds including percolation ponds, storm water sediment retention ponds, and Hertzler Ranch LAD storage pond; o Function of storm water, west-side shaft, and seepage outlet structure discharge channels; and o Function of underdrains. Current bonding for reclamation under the Operating Permit 00118 is funded for the amount of $23 000 000 through two financial instruments. The latest approved minor revision to the Operating Permit (MR21-003) has resulted in $22 973 159 of the $23 000 000 bond being allocated to approved activities, leaving $26 841 unallocated to reclamation obligations. A December 17th, 2021 letter from MDEQ identifies a preliminary revised bond estimate for the Stillwater Operating Permit No. 0118 of $60 129 104, which is an increase of approximately 261% from the current bond amount. Sibanye- Stillwater advised the Qualified Person that the final increase in bond amount is being negotiated and that Sibanye-Stillwater will fund an additional $24 000 000 to the bond by March 2022 while the negotiations are being completed. The Qualified Persons understand that the increased costs are being driven by State estimates of long-term monitoring costs and expanded water treatment associated with the East-side Waste Rock Storage Area. Table 53 presents the Stillwater Mine reclamation schedule and Table 54 presents the reclamation monitoring and maintenance schedule for the mine. Table 53: Stillwater Mine Reclamation Schedule Activity Interim Year 1 of Active Closure Year 2 of Active Closure Year 3 of Active Closure 1st Qtr 2nd Qtr 3rd Qtr 4th Qtr 1st Qtr 2nd Qtr 3rd Qtr 4th Qtr 1st Qtr 2nd Qtr 3rd Qtr 4th Qtr 1st Qtr 2nd Qtr 3rd Qtr 4th Qtr Water Treatment: Water Treatment - Underground water during demo Water Treatment - Tailings Imp Supernatant, Underdrain & O/F Water Treatment - Liberated tailings water during cap placement Site Care & Maintenance Reclamation Activity: Plant Site - Demolition & Removal of Plant Buildings Plant Site - Reclamation Mine - Underground Decommissioning Mine - Adit and Raise Closure Stillwater Impoundment Hertzler Impoundment Water Treatment & LAD Facilities - Demolition & Removal Power Line - Removal 231 Table 54: Stillwater Mine Closure Monitoring and Maintenance Schedule Based on the Qualified Person’s assessment of the reclamation bond calculation and discussions with in-house Environmental Specialists and taking into account the approved Reclamation Plans and understanding of the annual regulatory review of surety bases, the current reclamation costs and liabilities are reasonably managed and funded while existing sureties appear adequate to meet foreseeable commitments for the Stillwater Mine, contingent to final resolution of the Stillwater Mine bond negotiations. 19.2.6.3 East Boulder Mine Mine closure plans and bond bases of estimate are provided for the East Boulder Mine facilities in the Consolidated Operations and Reclamation Plan. Table 55 presents the East Boulder Mine reclamation schedule while Table 56 presents the reclamation monitoring and maintenance schedule for the mine.
232 Table 55: East Boulder Mine Reclamation Schedule Activity Interim Year 1 of Active Closure Year 2 of Active Closure Year 3 of Active Closure 1st Qtr 2nd Qtr 3rd Qtr 4th Qtr 1st Qtr 2nd Qtr 3rd Qtr 4th Qtr 1st Qtr 2nd Qtr 3rd Qtr 4th Qtr 1st Qtr 2nd Qtr 3rd Qtr 4th Qtr Water Treatment: Water Treatment - Adit Water Water Treatment - Tailings Imp Supernatant, Underdrain & O/F Water Treatment - Liberated tailings water during cap placement Site Care & Maintenance Reclamation Activity: Plant Site - Demolition & Removal of Plant Buildings ` Plant Site - Reclamation Mine - Underground Demolition and Disposal; Adit & Raise Closure Tailings Impoundment Reclamation Water Treatment & LAD Facilities - Demolition & Removal Boe Ranch Pipeline Reclamation Power Line (within permit area) + 2 sub-stations - Removal Access Roads - Reclamation Table 56: East Boulder Mine Closure Monitoring and Maintenance Schedule Concurrent reclamation has occurred since the start of operations. At the time of mine closure and reclamation, all surface facilities will be decommissioned, all structures will be disassembled and Year 1 Year 2 Year 3 Year 4 Year 5 Year 6 Year 7 Year 8 Groundwater Monitoring Surface Water Monitoring Adit Water Monitoring TSF Underdrain TSF Seepage through the Cover Salt Load Monitoring Abandon/Close Monitoring Wells One Time Tailings Volume, Density, Grade Structural Integrity Seepage Outlet Structure, Seepage through the Cover, Discharge Channel, Storm Water Channels Function of all Ponds (including Percolation Pond and Sediment Ponds) Function of Storm Water Channels and Basins, Adit Discharge Channel, TSF Seepage Outlet Channel Function of TSF Cover and Underdrain Outlet Structures Quarterly Quarterly Annual Closure Year ACTIVITY (1) Annual Annual (1) Closure and post‐closure monitoring and maintenance requirements are based on the 2012 Final EIS and ROD. Costs for ensuring these measures are carried out are included in the reclamation bond estimate calculations in Appendix G1 of the CORP. Post‐Closure Year Quarterly As Needed As Needed As Needed Site Maintenance Water Quality Monitoring Semiannual Monthly Semiannual Annual TSF Facility Monitoring Quarterly 233 removed, and the land will be reclaimed consistent with the approved post-mine land use. Roads that will remain include the main access road to the reclaimed portals, TSF, water conveyance structures, and water monitoring locations to allow for long-term monitoring and maintenance. These roads will be reclaimed when long-term monitoring and maintenance activities cease. Adequate volumes of soil materials are available for replacement of the required soil cover on all disturbances. Reclamation will meet the State of Montana provisions and requirements under the Montana Metal Mine Reclamation Act (MCA 82-4-336). The Closure and Reclamation Plan is also intended to meet the USFS requirements governing mineral development (36 CFR 228.8), and reclamation requirements under the Federal Seed Act (7 U.S.C., Section 1551-1610) and current USFS seeding guidelines. Reclamation of East Boulder Mine includes closure and post-closure management of adit waters, tailings storage facility, storm water management, and post-closure monitoring and maintenance programs. Closure and post-closure monitoring would address the following items until bond is released and all applicable water quality standards are met: • Groundwater and surface water quality would be monitored quarterly during closure and then twice per year according to the approved water quality monitoring plans and the MPDES permit in place during post-closure; • Adit water quality and quantity would be monitored three times per year until as long as the MPDES permit is in effect and/or until water quality standards are met; • Tailings impoundment function and structural integrity would be monitored annually during Years four and five and then once every five years; • Seepage outlet structures, seepage through cover discharge channel, adit discharge channel, storm water channel, and percolation pond function would be monitored annually for Years 4 to 8 and then once every five years; • Boe Ranch land application disposal, if constructed, would have a post-closure monitoring plan completed that describes the details of surface and groundwater sampling three times a year for up to five years to document water quality. The embankment on the storage pond would be reduced eliminating the need for inspection of embankment stability. This system has not been constructed or operated; • The post-closure maintenance plan would include the following items to be conducted annually during post-closure Years 4 to 8 and once every five years thereafter until bond is released, the MPDES permit is no longer needed, and water quality standards in effect at that time are met: o Function of all ponds including percolation ponds, storm water sediment retention ponds; o Function of stormwater, adit discharge, and seepage outlet structure discharge channels; o Function of seepage outlet structure and underdrain. Current bonding for reclamation under the Operating Permit 00149 is funded for the amount of $30 000 000, with $29 528 494 obligated (through Minor Revision MR21-003) and $471 506 unobligated; $22 562 726 of this amount is jointly obligated to DEQ/USFS while an additional $6 965 768 is obligated just to the USFS. No potential future increase in surety bond of the scale identified for the Stillwater Operating Permit No. 0118 has been identified for the East Boulder Operating Permit No. 00149. The potential Lewis Gulch TSF and the Dry Creek waste rock storage facility, when approved and constructed, would add to surety requirements until the East Boulder Mine is reclaimed and the incremental surety bond amount released. No estimates for those future reclamation liabilities are available. 234 Based on the Qualified Persons’ assessment of the reclamation bond calculation, discussions with Site Environmental Specialist and noting the approved Reclamation Plans and understanding of the annual regulatory review of surety bases, the current reclamation costs and liabilities are reasonably managed and funded, existing sureties appear adequate to meet foreseeable commitments for the East Boulder Mine. 19.2.6.4 Columbus Metallurgical Complex The Columbus Metallurgical Complex does not operate under a comparable Federal or State operating permit like the mines and, as such, no reclamation plan or bond is required. 235 CAPITAL AND OPERATING COSTS Overview Stillwater and East Boulder Mines and the Columbus Metallurgical Complex have been operated as integrated mature mining, ore processing and mineral beneficiation operations producing PGMs and base metals. Much of the long-term infrastructure and equipment required for the operations is in place, with upgrades currently being implemented to accommodate production increases anticipated in the LoM plans for the operations. The capital and operating costs for the three sites were estimated through an integrated, comprehensive budgeting process. Estimates of sustaining capital and operating costs were benchmarked to historical costs, while accounting for changes in production levels, escalation and contingencies. Project capital estimates for productivity enhancement projects were based on quotations from original equipment manufacturers and contractors. The foregoing constitutes sufficient justification for capital and operating cost budgeting for the operations. In addition, the accuracy level in the capital and operating costs utilised for LoM budgeting is within ±15% at up to 10% contingency for Proved Mineral Reserves and ±15% at up to 10% contingency for Probable Mineral Reserves. The capital and operating costs were utilised for the economic viability of the LoM plans for the mines and for the overall Sibanye-Stillwater US PGM Operations. All costs are presented in real terms and US$. Capital Costs Background Capital cost budgets present the costs into two categories, namely Category 1 and Category 2. Category 1 is essential capital for business continuity and sustaining production at the sites whereas Category 2 capital relates to projects intended for improved productivity, efficiency improvement and the management of environmental and social/administration matters. The Blitz Project, which started in 2011 and centred on expanding mining operations towards the Stillwater East Section and ore processing facilities, has been the most significant Category 2 contributor at Stillwater Mine and the Columbus Metallurgical Complex while the Fill The Mill Project has contributed to Category 2 capital at East Boulder Mine. Stillwater Mine 20.2.2.1 LoM Capital Expenditure Schedule The LoM capital cost schedule for the Stillwater Mine is presented in Table 57 where it is also compared with actual capital expenditure for the FY2019 to FY2021 period. The capital costs for Stillwater Mine include capital expenditure for mine and surface equipment, infrastructure, capitalised development, ongoing projects and environmental management, which relate to the mining and ore processing operations. In addition, significant capital expenditure has been budgeted for the Blitz Project (Stillwater East Growth and Project Capital) which will be concluded in
236 FY2023. After FY2023 and following the expected conclusion of the Blitz Project, the capital expenditure for mine and surface equipment and capitalised development dominate the capital schedule for Stillwater Mine, making up 35% to 100% of annual capital expenditure budgets from FY2024 to FY2055 (i.e., 82% of the FY2024 to FY2055 total capital budget). The total capital budget for Stillwater Mine for the FY2022 to FY2055 period is approximately $2.69 billion. Stillwater Mine’s capital expenditure in the capital budget is detailed by month for the first two years of the LoM and is annualised thereafter until the end of the LoM in FY2055. Long-term capital expenditure related to a specific project and/or scheduled equipment replacement is forecast in detail based on quotations from original equipment manufacturers and contractors. Routine long-term capital expenditure is forecast based on benchmarking with historical capital expenditure for the capitalised items. 20.2.2.2 Mining Capital The mining capital consists of several elements including development capital and capital associated with certain underground infrastructure upgrades. The following commentary outlines the main highlights of the capital expenditure schedule: • Mine and Surface Equipment Capital: An annual provision averaging approximately $31 million has been budgeted for the procurement of additional mining equipment for the Stillwater East and Stillwater West Sections between FY2022 and FY2023 in addition to the capital provision for the lifecycle replacement of existing equipment. Subsequently, capital expenditure averages approximately $20 million until FY2049 after which the capital declines gradually towards the end of the operations. Much of the primary and secondary underground equipment fleets are well past normal life cycle replacement as a result this provision is significantly higher than in recent history ($5 million to $13 million per annum), but necessary to make lifecycle replacements to achieve and sustain planned productivity levels; • Capitalised Development Capital: Capitalised development is defined as the part of primary development which extends or improves the LoM, such as footwall levels, access ramps, and infrastructure development. The capital allowance for development significantly increases in FY2022 onwards until FY2034 from historical levels of approximately $42 million to $56 million to new levels of $62 million to $117 million in line with the increasing levels of primary development at the expanding Stillwater East Section as well as strike extension development (east and west) in Stillwater West Section. The quantum of capitalised development capital progressively declines from approximately $50 million in FY2035 to approximately $274 thousand in FY2055; • Project Capital: This capital relates to specific, scheduled projects which enhance productivity or extend the life of mine, such as new tip and chute installations and rail extensions. This varies from year to year as requirements dictate; • Infrastructure Capital: This capital also relates to specific scheduled projects but with a focus on items such as communication, information technology (IT), software licences, power supply upgrades and the extension of the centralised blasting system as the mine footprint expands; • Other Capital: Other capital focuses on longer term strategic projects such as the development of LoM rock and ventilation passes several of which are scheduled in FY2022; • Stillwater East Expansion (Growth) Capital: This is capital budgeted for the development of the Stillwater East Section in terms of expansion items such as capitalised infrastructure, development, exploration drilling, underground equipment, surface infrastructure expansion, and concentrate handling. It also accounts for the capital required to establish a LoM rock pass system; 237 • Stillwater East Project Capital: This is capital budgeted for the establishment of permanent underground infrastructure and access, such as declines and ventilation raises. Stillwater East (Blitz) Growth and Project capital expenditure cease in FY2023 and, thereafter, all mining capital costs associated with the Stillwater East Section will be incorporated in the general Stillwater Mine mining capital expenditure budget. Based on the historical capital expenditure and the detail associated with the various capital budgets, the Qualified Person is of the view that sufficient capital provisions have been allowed for the support of the existing operations and the completion of the Blitz Project. 20.2.2.3 Concentrator Capital The budgeted concentrator capital comprises modest sustaining capital (average $300 thousand) for process equipment, buildings and infrastructure. There is also specific provisions of $2.6 million for maintenance/replacement of the River Bridge in FY2025. The capital expenditure for the finalisation of the concentrator expansion is captured in the Stillwater East Growth Capital budget. The concentrator capital allocation in FY2022 associated with the Blitz Project amounting to approximately $19 million comprises capital for finalising the concentrator expansion which started in FY2019. The bulk of the concentrator capacity expansion is completed although Covid-19 pandemic affected project delivery timelines, resulting in some of the sub-projects associated with the concentrator expansion being scheduled for completion in FY2022. 20.2.2.4 Environmental Capital Environmental capital expenditure encompasses TSF expansions, designs and implementation and associated infrastructure maintenance in addition to water and waste rock management and groundwater expenditure. The capital schedule shows expenditure ramp up starting in FY2022 to FY2026 driven by significant projects planned at tailings and waste rock storage facilities. The environmental capital costs include $3.6 million for the final closure and capping of the Nye TSF and Make-up Water Pond. A total of $4 million is planned to be spent on the East Waste Rock Storage Facility lining and expansion between FY2022 and FY2033. In addition, approximately $77 million is budgeted for the Hertzler TSF Stage 4 design and construction between FY2023 and FY2026, with an additional $59.3 million allocated between FY2042 and FY2044 for the Hertzler TSF Stage 5 Expansion. A further $41 million is to be spent on the Hertzler LAD pond relocation between FY2023 and FY2024 at the Hertzler TSF site. Approximately $17.7 million has been allocated for the East Waste Rock Storage Facility over the period FY2023 to FY2026. After the completion of the major projects, the forecast total annual environmental capital expenditure declines to levels of between $278 thousand and $3.9 million, which resemble historical levels. Allocations of $2.8 million to $3.9 million per annum over the FY2028 to FY2030 period relate to the Hertzler Stage 3/4 closures whereas allocations of $2.6 million to $3.3 million per annum over the FY2035 to FY2041 period relate to further expansion of the East Waste Rock Storage Facility. Capital expenditures levels of approximately $11.6 million cover various ongoing upgrades of water treatment facilities, general water management and disposal at the mine and TSFs over the LoM. 238 Table 57: Stillwater Mine Actual and LoM Capital Schedule FY2019 FY2020 FY2021 FY2022 FY2023 FY2024 FY2025 FY2026 FY2027 FY2028 FY2029 FY2030 FY2031 Mine and Surface Equipment US$ 5 705 434 13 435 548 5 075 929 27 349 580 34 992 750 18 783 382 20 132 126 22 071 998 16 565 492 24 274 748 20 421 248 20 715 248 39 232 566 Capitalised Development US$ 42 443 420 48 506 552 55 749 072 106 384 562 113 082 554 117 413 188 99 199 008 103 015 270 84 493 814 74 370 301 69 261 463 71 662 654 70 253 714 Project US$ 841 958 6 833 058 7 234 408 11 102 998 35 459 841 9 441 330 7 791 949 4 811 750 2 811 750 2 811 750 4 811 750 2 811 750 575 000 Infrastructure US$ 856 369 1 643 476 3 009 723 5 664 833 17 656 917 4 236 548 3 795 259 4 057 759 3 795 259 4 057 759 3 665 259 2 932 759 5 152 773 Other US$ 908 329 4 771 874 4 546 847 750 000 500 000 300 000 2 900 000 300 000 300 000 300 000 300 000 300 000 300 000 Stillwater East Growth US$ 69 097 034 77 200 176 108 142 113 136 879 599 120 949 000 - - - - - - - - Stillwater East Project US$ 37 823 369 24 518 113 36 634 309 15 082 136 - - - - - - - - - Environmental US$ 2 303 438 4 416 303 4 110 241 8 565 000 29 750 000 54 120 000 27 027 500 37 677 500 277 500 3 027 500 2 777 500 2 777 500 3 881 550 Total US$ 159 979 351 181 325 100 224 502 642 311 778 707 352 391 063 204 294 447 160 845 842 171 934 278 108 243 816 108 842 058 101 237 220 101 199 911 119 395 603 FY2032 FY2033 FY2034 FY2035 FY2036 FY2037 FY2038 FY2039 FY2040 FY2041 FY2042 FY2043 FY2044 Mine and Surface Equipment US$ 22 516 644 17 914 265 24 121 632 17 666 265 22 492 632 17 926 132 18 941 771 19 068 638 23 807 138 21 976 265 18 810 385 16 552 762 8 102 503 Capitalised Development US$ 68 356 446 73 176 177 62 076 949 49 891 264 40 612 794 36 918 031 27 990 236 7 498 651 4 483 541 4 420 930 4 400 134 4 013 898 3 511 382 Project US$ 2 350 000 350 000 2 100 000 100 000 100 000 2 100 000 100 000 2 350 000 350 000 2 100 000 100 000 2 100 000 100 000 Infrastructure US$ 4 064 048 3 622 759 3 885 259 3 622 759 3 885 259 3 492 759 2 510 259 3 814 048 3 372 759 3 635 259 3 372 759 3 635 259 2 077 630 Other US$ 300 000 300 000 300 000 300 000 300 000 300 000 300 000 300 000 300 000 300 000 300 000 300 000 175 000 Environmental US$ 638 750 638 750 388 750 2 638 750 2 638 750 2 888 750 3 088 750 3 088 750 3 338 750 3 088 750 23 088 750 20 388 750 19 369 375 Total US$ 98 225 887 96 001 952 92 872 590 74 219 039 70 029 435 63 625 672 52 931 016 36 120 086 35 652 188 35 521 205 50 072 028 46 990 669 33 335 890 FY2045 FY2046 FY2047 FY2048 FY2049 FY2050 FY2051 FY2052 FY2053 FY2054 FY2055 Mine and Surface Equipment US$ 18 310 385 23 307 138 21 401 265 18 310 385 16 052 762 7 527 503 12 175 626 1 032 250 620 000 100 000 81 750 - - Capitalised Development US$ 3 292 219 3 114 898 3 068 676 3 068 675 3 068 674 3 068 673 3 068 672 2 396 535 981 455 303 742 274 397 - - Project US$ 2 100 000 100 000 2 000 000 - 2 000 000 - - - 2 000 000 - - - - Infrastructure US$ 1 861 380 1 446 940 - - - - - - - - - - - Other US$ 175 000 175 000 - - - - - - - - - - - Environmental US$ 19 369 375 - 250 000 - 2 950 000 3 200 000 2 950 000 - 250 000 250 000 250 000 - - Total US$ 25 738 983 28 393 976 26 469 941 24 329 060 24 321 436 13 546 176 15 244 298 3 678 785 3 851 455 653 742 606 147 - - Cost Centre Unit Budget Budget Budget Cost Centre Unit Actual Cost Centre Unit 239 East Boulder Mine 20.2.3.1 LoM Capital Expenditure Schedule The LoM capital costs for East Boulder Mine also include capital for mine and surface equipment, infrastructure, capitalised development, ongoing projects and environmental management, which relate to the mining and ore processing operations. In addition, East Boulder Mine’s capital expenditure in the capital budget is detailed by month for the first two years of the LoM and is annualised thereafter until the end of the LoM in FY2061. Long-term capital related to a specific project and/or scheduled equipment replacement is forecast in detail based on quotations from original equipment manufacturers and contractors. For routine long-term capital expenditure is forecast based on benchmarking with historical capital expenditure for the capitalised items. The LoM capital cost schedule for East Boulder Mine is presented in Table 58 where it is also compared with actual capital expenditure for the FY2019 to FY2021 period. The total capital budget for East Boulder Mine for the FY2022 to FY2061 period is approximately $1.26 billion. 20.2.3.2 Mining Capital The mining capital consists of several elements including development capital and capital associated with certain underground infrastructure upgrades. The following salient points relating to mining capital costs are highlighted: • Mine and Surface Equipment Capital: This is an annual capital provision for the lifecycle replacement of mining equipment. As a result, this expenditure tends to be cyclical, with ramp up periods associated with major rebuilds and acquisition of new equipment as reflected in the current capital expenditure ramp up ($10.1 million to $18.5million per annum) that started in FY2021 and is expected to continue until FY2025 (coinciding with a significant increase in capital development). After FY2024, capital expenditure recedes to low levels of $1.7 million to $6.4 million per annum from FY 2025 to FY2029. This cyclical pattern continues to the end of the LoM although the lengths of the ramp up and low capital expenditure periods vary; • Capitalised Development: Capitalised development is the part of primary development such as footwall levels and access ramps, which extends LoM or optimises the LoM plan. The LoM Capitalised Development Capital budget includes a significant expenditure of $31 million per annum in FY2022 and FY2023, which exceeds historical levels. Thereafter, the capital allowance per annum resembles historical expenditure, ranging from approximately $13.5 million to $20 million, except for the last SIX years of the LoM during which significantly low levels of capitalised developments are planned/required; • Project Capital: With the conclusion of the various projects associated with the Fill The Mill Project, the TSF Stage 5/6 Project is the most significant remaining project and is forecast to end in FY2025. The TSF project will account for the bulk of the Project Capital expenditure per annum until FY2025. Subsequent to FY2025, Project Capital is set at $340 thousand per annum which is the historical expenditure typical for years when there are no major projects planned; • Other Capital: Other capital generally accounts for scheduled light vehicle replacements and minor infrastructural upgrades as required.
240 Based on the historical capital expenditure and the detail associated with the various capital budgets, the Qualified Person is of the view that sufficient mining capital provisions have been made to support the existing operations. 20.2.3.3 Concentrator Capital Due to the concentrator historically having been operated at 75%, there has been limited capital expenditure for sustaining the ore processing operations, with capital in the order of less than $1 million spend annually. The capital budget for the concentrator makes for modest provisions of between $325 thousand per annum in certain years on this basis for process equipment, buildings and infrastructure, which is aligned to the Stillwater Concentrator capital budget. As a result, the Qualified Person does not expect the sustaining capital costs for the concentrator to significantly increase in future due to the plant being operated at higher than 75% utilisation. 20.2.3.4 Environmental Capital Environmental capital expenditure encompasses TSF expansions, designs and implementation and associated infrastructure maintenance in addition to water and waste rock management and groundwater expenditure. The Environmental Capital budget includes an annual provision of $340 thousand for labour for the Lewis Gulch TSF embankment. Approximately $10.4 million is planned to be spent on the Dry Fork Waste Rock Storage Area Phase 1 development in FY2024 and FY2025 although the total expenditure for Phase 1 to Phase 4 and closure spread over the LoM is approximately $33 million. Approximately 21.3 million is budgeted for Stage 5/6 TSF lifts the FY2022 to FY2025 period, and therefore constitutes the bulk of the approximately $22.7 million per annum of project capital budget over this period. In addition, approximately 1.3 million is planned to be spent on the Lewis Gulch TSF EIS in FY2022 and FY2023, followed by $59 million on Lewis Gulch TSF construction between FY2026 and FY2028. Total capital expenditure on the Lewis Gulch TSF including further expansions and closure over the LoM is estimated to be $66.4 million. Further key elements of the capital expenditure under the environmental budget include an allowance of $100 million for the development of a new TSF between FY2039 and FY2042, an allowance of $5.3 million for the Stage 6 closure between FY2031 and FY2033, an allowance of $7.5 million for the closure of the future TSF and $25 million for final closure between FY2057 and FY2061. 241 Table 58: East Boulder Mine Actual and LoM Capital Schedule FY2019 FY2020 FY2021 FY2022 FY2023 FY2024 FY2025 FY2026 FY2027 FY2028 FY2029 Mine and Surface Equipment US$ 2 248 158 2 434 820 10 077 403 13 056 000 18 480 000 11 013 000 3 937 000 6 437 000 1 655 000 1 655 000 12 125 000 Capitalised Development US$ 12 890 762 12 315 037 20 937 932 30 587 583 17 682 474 18 757 810 17 821 491 17 130 051 16 927 641 18 138 621 19 932 442 Project (Excluding Met Complex) US$ 14 910 327 23 576 304 7 629 862 8 374 642 7 180 000 2 933 503 4 200 663 340 000 340 000 340 000 340 000 Other US$ 317 910 371 077 467 024 785 000 785 000 750 000 785 000 750 000 750 000 750 000 750 000 Environmental US$ 7 526 110 7 423 773 1 478 500 2 650 000 3 400 000 5 000 000 8 400 000 5 500 000 22 000 000 31 400 000 8 000 000 Total US$ 37 893 267 46 121 011 40 590 721 55 453 225 47 527 474 38 454 313 35 144 154 30 157 051 41 672 641 52 283 621 41 147 442 FY2030 FY2031 FY2032 FY2033 FY2034 FY2035 FY2036 FY2037 FY2038 FY2039 FY2040 Mine and Surface Equipment US$ 9 170 000 14 595 000 14 595 000 12 095 000 12 095 000 5 757 500 14 420 000 14 095 000 14 095 000 7 257 500 1 595 000 Capitalised Development US$ 19 237 855 17 249 300 16 905 328 16 109 505 16 914 234 16 124 875 15 942 439 15 801 690 16 202 579 16 093 055 17 910 210 Project (Excluding Met Complex) US$ 340 000 340 000 340 000 340 000 340 000 340 000 340 000 340 000 340 000 340 000 340 000 Other US$ 750 000 350 000 350 000 350 000 350 000 350 000 350 000 350 000 350 000 350 000 350 000 Environmental US$ 5 900 000 2 000 000 2 000 000 1 300 000 - - - - - - 28 000 000 Total US$ 35 397 855 34 534 300 34 190 328 30 194 505 29 699 234 30 072 375 31 052 439 30 586 690 30 987 579 57 040 555 48 195 210 FY2041 FY2042 FY2043 FY2044 FY2045 FY2046 FY2047 FY2048 FY2049 FY2050 FY2051 Mine and Surface Equipment US$ 1 595 000 1 595 000 9 551 000 7 055 000 10 016 000 4 787 000 10 095 000 10 095 000 11 095 000 11 095 000 13 095 000 Capitalised Development US$ 17 779 392 18 881 528 16 450 337 16 617 993 16 450 162 17 101 180 17 798 308 16 582 720 18 291 301 17 573 886 18 088 295 Project (Excluding Met Complex) US$ 340 000 340 000 340 000 340 000 340 000 340 000 340 000 340 000 340 000 340 000 340 000 Other US$ 350 000 350 000 350 000 350 000 350 000 350 000 350 000 350 000 350 000 350 000 - Environmental US$ 25 000 000 25 000 000 2 500 000 2 500 000 2 500 000 6 300 000 - - - - - Total US$ 45 064 392 46 166 528 29 191 337 26 862 993 29 656 162 28 878 180 28 583 308 27 367 720 30 076 301 29 358 886 31 523 295 FY2052 FY2053 FY2054 FY2055 FY2056 FY2057 FY2058 FY2059 FY2060 FY2061 Mine and Surface Equipment US$ 15 095 000 15 095 000 15 095 000 15 095 000 15 095 000 1 500 000 1 500 000 1 500 000 1 500 000 1 500 000 - Capitalised Development US$ 13 620 650 13 514 570 4 478 612 4 507 449 4 506 808 4 513 105 4 499 445 529 418 530 013 529 418 - Project (Excluding Met Complex) US$ 340 000 340 000 340 000 340 000 340 000 340 000 340 000 340 000 340 000 340 000 - Other US$ - - - - - - - - - - - Environmental US$ - - - - 5 000 000 12 500 000 12 500 000 5 000 000 - - - Total US$ 29 055 650 28 949 570 19 913 612 22 942 449 24 941 808 18 853 105 18 839 445 7 369 418 2 370 013 2 369 418 - Cost Centre Unit Budget Budget Budget Budget Cost Centre Unit Cost Centre Unit Actual Cost Centre Unit 242 Columbus Metallurgical Complex The Metallurgical Complex has experienced progressive increase in concentrate delivery from the concentrators as a result of ore production increases due to both the Fill The Mill Project at East Boulder Mine and Stillwater East Section at Stillwater Mine. The ore tons mined and processed continue to increase until FY2027 after which annual ore and concentrate outputs will stabilise as both mines operate at steady state production levels. As a result, and primarily as part of the Blitz Project, several capital projects have been underway at the Columbus Metallurgical Complex as described in Section 16.3, many of which have been completed. The LoM capital cost schedule for the Columbus Metallurgical Complex is presented in Table 59 where it is also compared with actual capital expenditure for the FY2019 to FY2021 period. With the finalisation of the various projects at the Columbus Metallurgical Complex in FY2023, sustaining capital becomes the single most significant capital cost element. The provision for sustaining capital ranges from $2.4 million to $18 million per annum, with the lower amounts reflecting modest annual maintenance of the various units of the complex and larger amounts associated with cyclic major furnace rebuilds. The total capital budget for the Columbus Metallurgical Complex for the FY2022 to FY2061 period is approximately $339.2 million. The Qualified Person is satisfied with the levels of project and sustaining capital provided for the various projects and for the continuity of operations at the Columbus Metallurgical Complex. 243 Table 59: Columbus Metallurgical Complex Actual and LoM Capital Expenditure FY2019 FY2020 FY2021 FY2022 FY2023 FY2024 FY2025 FY2026 FY2027 FY2028 FY2029 Mineral Beneficiation (off-mine) Sustaining Capital US$ 1 770 995 9 176 956 15 966 015 16 826 500 33 161 000 8 673 000 5 390 000 9 920 000 2 772 000 16 910 000 3 042 500 Smelter Projects US$ 18 067 436 13 595 415 8 540 183 4 280 000 2 300 000 - - - - - - BMR Projects US$ 211 281 3 122 414 1 545 358 - - - - - - - - Other (Recycle/Laboratory Expansion Projects) US$ - - 1 134 365 5 025 000 - - - - - - - Total US$ 20 049 712 25 894 785 27 185 921 26 131 500 35 461 000 8 673 000 5 390 000 9 920 000 2 772 000 16 910 000 3 042 500 FY2030 FY2031 FY2032 FY2033 FY2034 FY2035 FY2036 FY2037 FY2038 FY2039 FY2040 Mineral Beneficiation (off-mine) Sustaining Capital US$ 4 730 000 17 727 000 2 915 000 10 685 000 4 245 000 3 557 000 10 447 500 3 810 000 17 020 000 3 372 000 4 960 000 Smelter Projects US$ - - - - - - - - - - - BMR Projects US$ - - - - - - - - - - - Other (Recycle/Laboratory Expansion Projects) US$ - - - - - - - - - - - Total US$ 4 730 000 17 727 000 2 915 000 10 685 000 4 245 000 3 557 000 10 447 500 3 810 000 17 020 000 3 372 000 4 960 000 FY2041 FY2042 FY2043 FY2044 FY2045 FY2046 FY2047 FY2048 FY2049 FY2050 FY2051 Mineral Beneficiation (off-mine) Sustaining Capital US$ 17 815 000 5 070 000 13 378 500 5 603 000 4 400 000 9 770 000 2 917 000 16 950 000 4 925 000 4 427 500 17 957 000 Smelter Projects US$ - - - - - - - - - - - BMR Projects US$ - - - - - - - - - - - Other (Recycle/Laboratory Expansion Projects) US$ - - - - - - - - - - - Total US$ 17 815 000 5 070 000 13 378 500 5 603 000 4 400 000 9 770 000 2 917 000 16 950 000 4 925 000 4 427 500 17 957 000 FY2052 FY2053 FY2054 FY2055 FY2056 FY2057 FY2058 FY2059 FY2060 FY2061 Mineral Beneficiation (off-mine) Sustaining Capital US$ 2 410 000 10 160 000 3 385 000 3 407 000 9 820 000 3 597 500 3 020 000 2 527 000 3 350 000 2 495 000 - Smelter Projects US$ - - - - - - - - - - - BMR Projects US$ - - - - - - - - - - - Other (Recycle/Laboratory Expansion Projects) US$ - - - - - - - - - - - Total US$ 2 410 000 10 160 000 3 385 000 3 407 000 9 820 000 3 597 500 3 020 000 2 527 000 3 350 000 2 495 000 - Budget UnitCost Centre Cost Centre Unit Actual Budget Cost Centre Unit Budget Cost Centre Unit Budget
244 Operating Costs Background Operating costs for Stillwater and East Boulder Mines are reported according to mining and surface facilities categories and in terms of unit cost per ton of ore processed ($/ton processed) at the concentrators. Operating costs for the Columbus Metallurgical Complex are reported according to unit cost per ton of PGM-base metal concentrate smelted and include the costs of transporting concentrate all downstream mineral beneficiation and laboratory costs. The operating costs for the Columbus Metallurgical Complex also account for revenue credits from recycling operations and secondary metals. The costs are benchmarked to historical costs at each site and make allowances for escalation and increased productivity where necessary. The forecast operating costs for all operations are based on historic actual costs and are estimated to be within ±25% level of accuracy in real terms. Stillwater Mine 20.3.2.1 LoM Operating Costs The LoM operating costs for Stillwater Mine reported for the mining and surface facilities categories and in terms of unit cost per ton of ore processed are presented in Table 60. Significant escalation of the total unit operating costs from $275.24/ton milled in FY2019 to $308.29/ton milled in FY2022 (12% overall increase over the period) and a progressive decline relating to increasing tonnage output and steady state operations thereafter until FY2051 are the major highlights of the LoM operating costs. The costs are forecast to increase sharply in the last four years of the LoM in response to declining ore production. 20.3.2.2 Mining Operating Costs The unit mining operating costs for the Stillwater Mine consist of the following key costing elements: • Stope mining costs dependant on mining method employed; • Primary development costs depending on type; • Secondary development costs depending on type; • Underground operational support services depending on activity; • Surface facilities; and • Site specific general and administration costs. In general, unit mining operating costs constitute 88% of the total operating cost for Stillwater Mine over the LoM. The historical and forecast LoM unit mining operating costs reflect significant year-on-year escalation (1% to 6%) between FY2019 ($244.92/ton milled) and FY2021 ($259.60/ton milled) driven mainly by significant increases in underground support costs (driven by high increases in steel costs), blasting costs following the switch to centralised blasting and increased use of higher cost contractors in place of lower cost inhouse personnel due to high employee attrition. Linked to these cost increases are the significant increases in stoping and primary development costs. The mining unit operating cost is forecast to progressively decline to $160.39/ton milled in FY2051, reflecting the combined effect of increasing ore mining and operating at steady state level. The step change in the declining trend in FY2043 is due to a reduction in mining activity (primary development and infrastructure establishment) 245 as the mine draws to a close. The mining operating costs are forecast to increase in the last four years of LoM due to declining ore production. 20.3.2.3 Surface Facilities Operating Costs The unit operating costs for processing of the ores and maintenance are included in the Surface Facilities Cost Category. This category comprises the following elements: • Concentrator costs; • Paste plant costs; • CRF plant costs; • Sand plant costs; • Shaft/hoisting and surface crusher area costs; and • Hertzler TSF costs. The unit operating cost history and budget for the surface facilities follows a similar trend as for the mining operating costs, with significant year-on-year escalation (5% to 6%) between FY2019 ($30.32/ton milled) and FY2021 ($33.63/ton milled), reflecting significant escalation in the price of inputs across the board. From the FY2021 peak, there is significant reversal of the trend as the costs decline to $27.49/ton milled in FY2024 and gradually reducing to $25.81/ton milled in FY2044 due to increasing production output and operating at the steady state level. A notable increase in paste plant costs in FY2045 will see the surface facilities unit operating cost rising to $27.93/ton milled followed by a reduction to $27.57/ton milled in FY2047, which is the cost forecast for the remaining years of the LoM. East Boulder Mine 20.3.3.1 LoM Operating Costs The LoM operating costs are also reported according to mining and surface facilities categories and in terms of unit cost per ton of ore processed as shown in Table 61. This shows rapid escalation of the total unit operating costs from $151.11/ton milled in FY2019 to $195.00/ton milled in FY2022 (29% overall increase over the period). The forecast total unit operating cost gradually recedes to $175.06/ton milled in FY2027 from where it fluctuates between $174.84/ton and $178.29/ton milled until FY2049. Subsequently, the total operating costs are forecast to increase and fluctuate between $174.84/ton and $188.49/ton milled until FY2054 due to a 7% reduction in milled tonnage. Thereafter, the costs decrease as the operations draw close to the end of the LoM. 20.3.3.2 Mining Operating Costs The unit mining operating costs for the East Boulder Mine consist of the following key costing elements: • Stope mining costs dependant on mining method employed; • Primary development costs depending on type; • Secondary development costs depending on type; • Underground operational support services depending on activity; • Surface facilities; and • Site specific general and administration costs. 246 In general, unit mining operating costs constitute 80% of the total unit operating cost for East Boulder Mine over the LoM. As a result, the unit mining operating costs follow the same trend as the total unit operating costs. These indicate year-on-year increases of 6% to 18% between FY2019 ($131.99/ton milled) and FY2022 ($174.59/ton milled), also driven by significant increases in underground support costs, blasting costs and increased use of contractors as well as the linked increases in stoping and primary development costs. The costs are forecast to stabilise after a reduction to $155.60/ton milled in FY2027, fluctuating between $154.79/ton and $158.24/ton milled until FY2049. Subsequently, the costs rise due to the 7% reduction in milled tonnage, fluctuating at the new level of $154.13/ton and $166.82/ton milled until FY2054. The costs also decline towards the end of the LoM following a gradual reduction in mining activity in the final seven years of the LoM. 20.3.3.3 Surface Facilities Operating Costs The unit operating costs for the processing of the ores and maintenance are included in the Surface Facilities Cost Category. This category comprises the following elements: • Concentrator costs; • Sand plant costs; • Surface crew costs; and • Tailings impoundment costs. The unit operating cost history and budget for the surface facilities indicate modest year-on-year growth and fluctuations between FY2019 ($19.13/ton milled) and FY2022 ($20.40/ton milled). From the FY2022 peak, the costs are forecast to significantly decline to $18.74/ton milled in FY2025 due to a reduction in sand plant and surface crew costs after which they gradually revert to historical levels of between $19.46/ton and $20.05/ton milled until FY2049. Subsequently, the costs increase in response to the 7% tonnage reduction discussed already to new levels of between $20.11/ton and $21.68/ton milled until FY2056. The costs also decline significantly to $13.99/ton milled due to a 27% reduction in the concentrator operating costs final five years of the LoM. Columbus Metallurgical Complex The LoM unit operating costs for the Columbus Metallurgical Complex are presented in terms of unit cost per ton of PGM-base metal concentrate smelted in Table 62. The costs account for the following elements: • Concentrate transportation; • Smelting; • Refining (which includes environmental, safety, human resources and maintenance); • Laboratory costs; • Site support services (includes purchasing and warehousing); • Site General & Administrative costs (which include all corporate overhead costs); • By-product credits (returned from Precious Metal Refinery); and • Secondary credits (the cost incurred in the catalyst recycling process and credits received for this). The forecast unit operating costs for the Columbus Metallurgical Complex are in line with those historically achieved. The Qualified Person notes the substantial beneficial impact of recycling and by- 247 product credits on the overall unit cost of operation and the benefits arising from the integration of the mining, ore processing and mineral beneficiation operations. As the output from Stillwater Mine declines towards the end of the LoM in FY2050, the unit operating costs for the Columbus Metallurgical Complex increase but remain negative for the remainder of the LoM. Accordingly, there is significant merit in maintaining production at the steady state level and extending the LoM for Stillwater Mine through ongoing definition drilling, which generates additional Indicated and Measured Mineral Resources for inclusion in the LoM production schedule in future.
248 Table 60: Actual and LoM Operating Costs for Stillwater Mine FY2019 FY2020 FY2021 FY2022 FY2023 FY2024 FY2025 FY2026 FY2027 FY2028 FY2029 FY2030 FY2031 FY2032 FY2033 FY2034 FY2035 FY2036 FY2037 Mining: Stope Mining $/ton processed 72.21 71.37 72.04 56.96 59.18 60.83 60.84 56.43 54.03 53.05 53.51 53.18 53.05 51.97 51.66 52.87 53.05 52.33 53.18 Primary Development $/ton processed 21.95 20.97 26.87 56.92 51.00 63.25 47.99 45.95 40.70 37.55 34.69 36.47 36.16 35.32 37.32 36.88 34.56 33.67 32.45 Underground Support $/ton processed 125.44 142.40 134.57 133.02 124.99 121.55 116.85 117.55 115.45 109.79 107.08 105.76 106.65 108.24 109.39 109.49 108.98 108.05 109.71 Site General & Administrative $/ton processed 25.32 23.32 26.11 28.71 25.06 22.74 22.32 22.20 21.91 21.83 22.21 21.53 21.53 21.53 21.53 21.53 21.53 21.53 21.53 Subtotal $/ton processed 244.92 258.06 259.60 275.61 260.23 268.37 247.99 242.14 232.08 222.22 217.48 216.93 217.38 217.07 219.89 220.77 218.11 215.59 216.86 Surface Facilities: Concentrator $/ton processed 14.11 14.98 15.26 15.20 14.37 12.52 12.28 12.22 12.06 12.02 12.22 11.85 11.85 11.85 11.85 11.85 11.85 11.85 11.85 Paste Plant $/ton processed 4.34 4.17 3.24 3.17 2.74 2.72 2.69 2.53 2.41 2.42 2.59 2.69 2.52 2.53 2.43 2.31 2.35 2.36 2.38 Sand Plant $/ton processed 3.51 4.01 4.35 4.16 3.84 3.55 3.50 3.48 3.45 3.44 3.48 3.40 3.40 3.41 3.40 3.40 3.40 3.41 3.40 Surface Crew $/ton processed 3.88 4.07 5.58 5.39 4.87 4.39 4.31 4.28 4.23 4.22 4.29 4.15 4.15 4.16 4.15 4.15 4.15 4.16 4.15 Shaft/Hoist/Crusher $/ton processed 3.06 3.35 3.62 3.11 2.81 2.53 2.48 2.47 2.44 2.43 2.47 2.39 2.39 2.40 2.39 2.39 2.39 2.40 2.39 TSF Costs - Hertzler TSF $/ton processed 1.42 1.19 1.58 1.65 1.57 1.78 1.74 1.73 1.71 1.71 1.73 1.68 1.68 1.68 1.68 1.68 1.68 1.68 1.68 Subtotal $/ton processed 30.32 31.76 33.63 32.68 30.21 27.49 27.00 26.72 26.30 26.23 26.78 26.17 26.00 26.03 25.91 25.79 25.84 25.86 25.86 Total Mining and Processing Costs $/ton processed 275.24 289.82 293.23 308.29 290.44 295.87 275.00 268.86 258.38 248.45 244.27 243.10 243.39 243.10 245.80 246.56 243.95 241.45 242.72 FY2038 FY2039 FY2040 FY2041 FY2042 FY2043 FY2044 FY2045 FY2046 FY2047 FY2048 FY2049 FY2050 FY2051 FY2052 FY2053 FY2054 FY2055 Mining: Stope Mining $/ton processed 53.06 52.96 50.67 52.42 53.07 51.24 51.49 51.79 54.67 54.67 54.67 54.67 54.67 54.67 54.67 54.67 54.67 54.67 - Primary Development $/ton processed 32.51 26.15 24.78 25.05 25.13 17.93 9.90 5.50 1.63 1.08 1.08 1.08 1.08 1.08 1.08 1.08 1.08 1.08 - Underground Support $/ton processed 106.99 105.79 105.64 106.71 107.03 98.03 88.20 83.43 83.91 83.39 83.39 83.39 83.39 83.39 95.29 171.42 448.43 490.84 - Site General & Administrative $/ton processed 21.53 21.53 21.53 21.53 21.53 21.53 21.53 21.53 21.53 21.25 21.25 21.25 21.25 21.25 21.25 21.25 21.26 21.26 - Subtotal $/ton processed 214.09 206.43 202.62 205.71 206.76 188.73 171.13 162.25 161.74 160.39 160.39 160.39 160.39 160.39 172.28 248.42 525.44 567.85 - Surface Facilities: Concentrator $/ton processed 11.85 11.85 11.85 11.85 11.85 11.85 11.85 11.85 11.85 11.69 11.69 11.69 11.69 11.69 11.69 11.69 11.69 11.69 - Paste Plant $/ton processed 2.30 2.25 2.27 2.34 2.38 2.34 2.31 2.94 4.45 4.40 4.40 4.40 4.40 4.40 4.40 4.40 4.40 4.40 - Sand Plant $/ton processed 3.40 3.40 3.41 3.40 3.40 3.40 3.41 3.40 3.40 3.36 3.36 3.36 3.36 3.36 3.36 3.36 3.36 3.36 - Surface Crew $/ton processed 4.15 4.15 4.16 4.15 4.15 4.15 4.16 4.15 4.15 4.10 4.10 4.10 4.10 4.10 4.10 4.10 4.10 4.10 - Shaft/Hoist/Crusher $/ton processed 2.39 2.39 2.40 2.39 2.39 2.39 2.40 2.39 2.39 2.36 2.36 2.36 2.36 2.36 2.36 2.36 2.36 2.36 - TSF Costs - Hertzler TSF $/ton processed 1.68 1.68 1.68 1.68 1.68 1.68 1.68 1.68 1.68 1.66 1.66 1.66 1.66 1.66 1.66 1.66 1.66 1.66 - Subtotal $/ton processed 25.78 25.73 25.77 25.82 25.86 25.82 25.81 26.42 27.93 27.57 27.57 27.57 27.57 27.57 27.57 27.57 27.57 27.57 - Total Mining and Processing Costs $/ton processed 239.87 232.16 228.39 231.52 232.62 214.54 196.94 188.66 189.68 187.96 187.96 187.96 187.96 187.96 199.86 275.99 553.01 595.42 - Cost Centre Unit Budget Cost Centre Unit Actual Budget 249 Table 61: Actual and LoM Operating Cost for East Boulder Mine FY2019 FY2020 FY2021 FY2022 FY2023 FY2024 FY2025 FY2026 FY2027 FY2028 FY2029 FY2030 FY2031 FY2032 FY2033 FY2034 FY2035 FY2036 FY2037 FY2045 FY2046 FY2047 Mining: Stope Mining $/ton processed 44.13 47.13 60.37 58.86 58.41 57.09 56.93 56.69 55.30 54.93 53.93 54.58 55.36 55.08 55.36 55.11 55.36 55.35 55.36 55.36 55.38 55.09 Primary Development $/ton processed 8.29 8.06 14.91 20.72 11.28 10.55 10.32 9.59 9.62 10.17 10.97 10.68 9.74 9.57 9.20 9.60 9.21 8.85 8.85 9.16 9.42 10.08 Underground Support $/ton processed 64.10 71.71 75.42 78.61 80.19 78.10 76.24 77.71 74.50 75.90 74.20 76.05 74.75 75.49 74.17 75.58 74.17 75.59 74.39 74.71 76.26 74.83 Site General & Administrative $/ton processed 15.47 12.79 13.86 16.40 16.23 16.14 16.19 16.19 16.18 16.14 16.18 16.18 16.18 16.14 16.18 16.18 16.18 16.14 16.18 16.18 16.18 16.18 Subtotal $/ton processed 131.99 139.69 164.56 174.59 166.11 161.88 159.67 160.18 155.60 157.14 155.29 157.49 156.02 156.27 154.91 156.48 154.92 155.92 154.79 155.41 157.24 156.18 Surface Facilities: Concentrator $/ton processed 13.69 13.74 13.75 14.32 14.11 13.21 13.24 13.86 13.90 13.90 13.99 14.04 14.09 14.23 14.32 14.32 14.32 14.28 14.32 14.32 14.32 14.32 Sand Plant $/ton processed 2.27 2.34 2.22 2.21 2.29 2.25 2.20 2.20 2.20 2.19 2.20 2.20 2.20 2.19 2.20 2.20 2.20 2.19 2.20 2.20 2.20 2.20 Surface Crew $/ton processed 3.16 3.56 3.50 3.88 3.52 3.34 3.30 3.34 3.37 3.38 3.42 3.45 3.48 3.50 3.54 3.54 3.54 3.53 3.54 3.54 3.54 3.54 Subtotal $/ton processed 19.13 19.64 19.46 20.40 19.92 18.80 18.74 19.40 19.46 19.48 19.60 19.68 19.76 19.92 20.05 20.05 20.05 20.00 20.05 20.05 20.05 20.05 Total Mining and Processing Costs $/ton processed 151.11 159.33 184.03 195.00 186.03 180.68 178.42 179.58 175.06 176.62 174.89 177.17 175.79 176.20 174.96 176.53 174.97 175.92 174.84 175.46 177.29 176.23 FY2038 FY2039 FY2040 FY2041 FY2042 FY2043 FY2044 FY2048 FY2049 FY2050 FY2051 FY2052 FY2053 FY2054 FY2055 FY2056 FY2057 FY2058 FY2059 FY2060 FY2061 Mining: Stope Mining $/ton processed 55.38 55.36 55.08 55.09 55.11 55.36 55.35 55.35 55.09 56.43 56.40 59.89 59.85 60.14 60.14 60.17 43.75 43.75 43.75 43.78 43.75 - Primary Development $/ton processed 8.99 8.99 10.05 10.07 10.72 9.16 9.17 9.14 10.32 10.49 10.83 8.61 8.61 3.28 3.28 3.28 3.28 3.28 0.38 0.38 0.38 - Underground Support $/ton processed 75.81 74.53 76.00 74.83 76.23 74.71 75.90 75.90 75.08 78.96 77.95 80.82 79.42 74.48 76.20 76.22 55.10 54.86 54.86 54.88 54.86 - Site General & Administrative $/ton processed 16.18 16.18 16.14 16.18 16.18 16.18 16.14 16.14 16.18 17.39 17.39 17.49 17.49 16.23 16.68 16.68 11.29 11.29 11.29 11.29 11.29 - Subtotal $/ton processed 156.36 155.06 157.27 156.16 158.24 155.41 156.56 156.53 156.67 163.27 162.57 166.82 165.37 154.13 156.29 156.34 113.41 113.17 110.27 110.33 110.27 - Surface Facilities: Concentrator $/ton processed 14.32 14.32 14.28 14.32 14.32 14.32 14.28 14.28 14.32 15.39 15.39 15.48 15.48 14.36 14.76 14.76 9.99 9.99 9.99 9.99 9.99 - Sand Plant $/ton processed 2.20 2.20 2.19 2.20 2.20 2.20 2.19 2.19 2.20 2.35 2.36 2.37 2.37 2.20 2.26 2.26 1.53 1.53 1.53 1.53 1.53 - Surface Crew $/ton processed 3.54 3.54 3.53 3.54 3.54 3.54 3.53 3.53 3.54 3.81 3.81 3.83 3.83 3.55 3.65 3.65 2.47 2.47 2.47 2.47 2.47 - Subtotal $/ton processed 20.05 20.05 20.00 20.05 20.05 20.05 20.00 20.00 20.05 21.55 21.55 21.68 21.68 20.11 20.67 20.67 13.99 13.99 13.99 13.99 13.99 - Total Mining and Processing Costs $/ton processed 176.41 175.12 177.26 176.22 178.29 175.46 176.56 176.53 176.72 184.82 184.12 188.49 187.05 174.24 176.96 177.01 127.40 127.16 124.26 124.32 124.26 - Cost Centre Unit Cost Centre Unit Actual Budget Budget 250 Table 62: Actual and LoM Operating Costs for the Columbus Metallurgical Complex FY2019 FY2020 FY2021 FY2022 FY2023 FY2024 FY2025 FY2026 FY2027 FY2028 FY2029 FY2030 FY2031 FY2032 FY2033 Mineral Beneficiation Costs (off-mine) Concentrate Transportation $/ton smelted 120.66 92.84 113.76 150.10 149.70 157.88 161.19 159.93 157.13 145.32 135.00 134.18 132.49 131.02 130.36 Smelting $/ton smelted 1 003.88 827.54 798.66 808.53 756.68 723.45 736.62 710.05 698.13 699.31 698.42 722.40 698.57 698.19 699.51 Refining $/ton smelted 250.60 198.83 178.82 187.92 179.05 171.73 175.06 167.96 162.26 162.50 161.90 168.16 161.91 159.31 158.54 Laboratory $/ton smelted 189.23 127.13 124.31 123.46 113.98 110.13 112.25 107.97 106.06 106.25 106.11 109.97 106.13 106.08 106.29 Columbus Support Services $/ton smelted 78.73 152.45 - - - - - - - - - - - - - Site General & Administrative $/ton smelted 680.13 688.43 1 268.20 1 277.88 1 172.34 1 108.66 1 133.52 1 083.39 1 060.91 1 063.14 1 061.45 1 106.69 1 061.75 1 061.02 1 063.51 By-product credits $/ton smelted -1 181.37 -1 831.61 -2 331.10 -1 657.36 -1 670.52 -1 799.98 -1 862.25 -1 838.03 -1 791.71 -1 654.91 -1 522.64 -1 509.06 -1 477.55 -1 462.45 -1 450.79 Secondary credits including interest $/ton smelted -1 277.77 -1 770.15 -3 137.82 -1 738.46 -1 656.31 -1 619.20 -1 664.64 -1 592.82 -1 560.15 -1 563.49 -1 561.02 -1 627.57 -1 561.48 -1 560.41 -1 564.09 Total Beneficiation Costs $/ton smelted -135.92 -1 514.54 -2 985.17 -847.92 -955.08 -1 147.33 -1 208.26 -1 201.55 -1 167.36 -1 041.88 -920.80 -895.22 -878.17 -867.25 -856.66 FY2034 FY2035 FY2036 FY2037 FY2045 FY2046 FY2047 FY2038 FY2039 FY2040 FY2041 FY2042 FY2043 FY2044 FY2048 Mineral Beneficiation Costs (off-mine) Concentrate Transportation $/ton smelted 128.76 126.00 127.68 131.53 131.17 128.13 124.24 123.50 125.46 124.50 127.17 124.80 128.44 129.76 130.48 Smelting $/ton smelted 697.62 697.98 696.80 697.06 697.02 696.79 696.03 696.61 696.79 697.79 699.32 699.47 700.09 699.70 698.88 Refining $/ton smelted 158.21 158.44 157.27 157.30 157.40 156.75 155.97 156.07 156.19 156.01 159.24 155.92 162.07 161.54 160.67 Laboratory $/ton smelted 105.99 106.05 105.86 105.90 105.89 105.86 105.74 105.83 105.86 106.02 106.26 106.30 106.38 106.32 106.19 Site General & Administrative $/ton smelted 1 059.95 1 060.63 1 058.39 1 058.90 1 058.81 1 058.38 1 056.95 1 058.04 1 058.38 1 060.27 1 063.16 1 063.45 1 064.61 1 063.86 1 062.33 By-product credits $/ton smelted -1 431.53 -1 399.21 -1 412.37 -1 457.40 -1 458.16 -1 423.91 -1 373.66 -1 361.46 -1 382.52 -1 372.36 -1 408.28 -1 375.52 -1 427.77 -1 447.29 -1 455.55 Secondary credits including interest $/ton smelted -1 558.86 -1 559.86 -1 556.58 -1 557.32 -1 557.21 -1 556.58 -1 554.48 -1 556.09 -1 556.59 -1 559.38 -1 563.64 -1 564.06 -1 565.78 -1 564.69 -1 562.44 Total Beneficiation Costs $/ton smelted -839.85 -809.98 -822.94 -864.03 -865.07 -834.58 -789.21 -777.50 -796.44 -787.15 -816.77 -789.65 -831.96 -850.81 -859.45 FY2049 FY2050 FY2051 FY2052 FY2053 FY2054 FY2055 FY2056 FY2057 FY2058 FY2059 FY2060 FY2061 Mineral Beneficiation Costs (off-mine) Concentrate Transportation $/ton smelted 130.20 130.37 123.86 127.14 124.41 124.84 123.66 128.81 125.08 125.08 125.08 125.08 125.08 - - Smelting $/ton smelted 699.65 714.45 738.95 844.95 1 072.86 1 210.51 1 265.50 1 386.89 1 586.32 1 586.32 1 586.32 1 586.32 1 586.32 - - Refining $/ton smelted 160.89 163.77 169.14 196.74 251.07 286.36 300.36 332.24 382.14 382.14 382.14 382.14 382.14 - - Laboratory $/ton smelted 106.31 108.70 112.64 129.70 166.39 188.55 197.40 216.93 249.03 249.03 249.03 249.03 249.03 - - Site General & Administrative $/ton smelted 1 063.77 1 091.70 1 137.90 1 337.84 1 767.72 2 027.36 2 131.09 2 360.06 2 736.21 2 736.21 2 736.21 2 736.21 2 736.21 - - By-product credits $/ton smelted -1 453.28 -1 456.40 -1 381.55 -1 368.83 -1 328.30 -1 299.56 -1 272.51 -1 329.88 -1 282.79 -1 259.93 -1 259.93 -1 259.93 -1 259.93 - - Secondary credits including interest $/ton smelted -1 564.57 -1 605.65 -1 673.60 -1 967.68 -2 599.96 -2 981.84 -3 134.43 -3 471.21 -4 024.47 -4 024.49 -4 024.51 -4 024.52 -4 024.52 - - Total Beneficiation Costs $/ton smelted -857.02 -853.06 -772.67 -700.15 -545.80 -443.79 -388.93 -376.15 -228.50 -205.65 -205.67 -205.68 -205.68 - - Cost Centre Unit Budget Budget Cost Centre Unit Actual Budget Cost Centre Unit 251 ECONOMIC ANALYSIS Background The LoM production, capital and operating cost schedules for Stillwater and East Boulder Mines and the Columbus Metallurgical Complex were employed for the economic viability testing of the LoM plans for each mine and the consolidated LoM plan for the Sibanye-Stillwater US PGM Operations. The consolidated LoM plan forms the basis for the Mineral Reserve estimates for Stillwater and East Boulder Mines reported in this Technical Report Summary. The LoM production schedules for Stillwater and East Boulder Mines are discussed in Section 15.8 while the associated LoM capital and operating costs are presented in Section 20. No exchange rates have been used for the economic analysis as all metal prices and costs are reported in the US currency. The Qualified Person for Mineral Reserves has considered and applied the macroeconomic trends, data and assumptions, marketing information and commodity prices, taxation and royalties provided by Sibanye-Stillwater set out below. The outputs of the economic viability testing are reliant on these forward-looking economic parameters and assumptions which may be subject to revision as circumstances change. Economic Viability Testing Method The Discounted Cash Flow (DCF) methodology has been used for the economic testing of the individual LoM plans and consolidated LoM Plan for Sibanye-Stillwater US PGM Operations and the Mineral Reserves for Stillwater and East Boulder Mines. The DCF model is referred to as the Ore Reserve Economic Test (ORET) Model. With the DCF approach, a negative cash flow or NPV indicates sub-economic production whereas a positive cash flow or NPV indicates economic production and that the declaration of Mineral Reserves is justified. The method, therefore, allows for the identification of sub- economic production for exclusion through production schedule production schedule tail cutting if the sub-economic production occurs towards the final years of the LoM. A first-pass LoM plan for each mine that includes the LoM production schedule and all operating and capital expenses, manpower requirements, equipment replacement and purchase, and primary and secondary development including ventilation and haulages that are needed to execute the plan was incorporated into the ORET Model. The first pass LoM plans for Stillwater and East Boulder Mines were consolidated to produce a single LoM Plan for the Sibanye-Stillwater US PGM Operations. Cash flows have been forecast and discounted back to an NPV using a range of real discount rates from 2.5% to 7.5%. The LoMs for Stillwater and East Boulder Mines are 35 and 39 years, respectively. The 35-year LoM plan for Stillwater Mine contemplates driving footwall lateral declines and other infrastructure into areas currently classified as Inferred Mineral Resources, which are not scheduled for mining in the current LoM plan for the mine. Both mines have expanded in this manner over the years. Accordingly, the fact that Stillwater and East Boulder Mines have different LoMs is not a material issue. The ORET Model start date is January 1, 2022 and the LoM for the Sibanye-Stillwater US PGM Operations is 39 years. Financial years commencing 1 January have been used and each year’s cash flow is deemed to have occurred at the end of the period – i.e., on December 31. No assessed losses,
252 shareholder loan accounts or other balance sheet circumstances have been accounted for and, therefore, the cash flows are ungeared. Company tax and state royalty calculations have been incorporated into the computation of cash flows. Economic Assumptions and Forecasts Taxation With guidance from Sibanye-Stillwater, the Qualified Person for Mineral Reserves applied an aggregate tax rate of 25.9% for economic testing of the individual and consolidated LoM Plan for the Sibanye- Stillwater US PGM Operations in support of the declaration of Mineral Reserves for Stillwater and East Boulder Mines. This rate is made up of the cash tax rates for the State of Montana and Federal taxes. Taxation is calculated on real cash flows. Metal Price Forecast For the economic viability testing of the individual and the consolidated LoM Plan for Sibanye-Stillwater US PGM Operations, the forward-looking palladium and platinum metal prices as summarised in Table 42 have been used, and the rationale for the price determination is set out in Section 18.4. These prices have also been submitted by Sibanye-Stillwater to the SEC for review and noting. Discount Rate Sibanye-Stillwater’s weighted average cost of capital (WACC) as at December 31, 2021 is 5% based on corporate planning guidance. The Qualified Person for Mineral Reserves reviewed the base data utilised for the calculation of the WACC as well as the WACC calculation methodology for reasonableness. From the review, the Qualified Person concluded that the WACC of 5% is reasonable for the discounting of cash flows for the Sibanye-Stillwater US PGM Operations. DCF Results and Sensitivity Analysis DCF Model An abridged cash-flow model showing expected annual cash flows for Stillwater and East Boulder Mines and the combined Sibanye-Stillwater US PGM Operations is presented in Table 63. 253 Table 63: Abridged Cash Flow Results East Boulder Mine 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 Palladium ounces produced 201,990 202,774 201,666 201,115 201,666 201,115 201,666 201,115 201,666 201,115 201,702 201,151 201,702 201,151 196,628 195,959 200,893 208,577 197,059 197,003 197,542 197,003 197,959 197,003 197,542 197,003 197,959 197,003 183,760 178,287 180,788 180,788 180,788 180,788 180,788 180,788 180,788 180,788 180,788 180,788 - - - - Platinum ounces produced 57,892 58,117 57,799 57,641 57,799 57,641 57,799 57,641 57,799 57,641 57,809 57,651 57,809 57,651 56,355 56,163 57,577 59,780 56,478 56,462 56,617 56,462 56,737 56,462 56,617 56,462 56,737 56,462 52,667 51,098 51,815 51,815 51,815 51,815 51,815 51,815 51,815 51,815 51,815 51,815 - - - - Combined ounces produced 259,882 260,891 259,464 258,755 259,464 258,755 259,464 258,755 259,464 258,755 259,512 258,803 259,512 258,803 252,983 252,122 258,471 268,357 253,537 253,465 254,159 253,465 254,696 253,465 254,159 253,465 254,696 253,465 236,427 229,385 232,603 232,603 232,603 232,603 232,603 232,603 232,603 232,603 232,603 232,603 - - - - Palladium revenues $m 239.9 240.8 239.5 238.8 239.5 238.8 239.5 238.8 239.5 238.8 239.5 238.9 239.5 238.9 233.5 232.7 238.6 247.7 234.0 233.9 234.6 233.9 235.1 233.9 234.6 233.9 235.1 233.9 218.2 211.7 214.7 214.7 214.7 214.7 214.7 214.7 214.7 214.7 214.7 214.7 - - - - Platinum revenues $m 72.4 72.6 72.2 72.1 72.2 72.1 72.2 72.1 72.2 72.0 72.2 72.0 72.2 72.0 70.4 70.1 71.9 74.7 70.5 70.5 70.7 70.5 70.9 70.5 70.7 70.5 70.9 70.5 65.8 63.8 64.7 64.7 64.7 64.7 64.7 64.7 64.7 64.7 64.7 64.7 - - - - Gross Revenues $m 312.2 313.4 311.7 310.9 311.7 310.9 311.7 310.9 311.7 310.8 311.7 310.9 311.7 310.9 303.9 302.8 310.5 322.4 304.5 304.5 305.3 304.5 305.9 304.5 305.3 304.5 305.9 304.5 284.0 275.5 279.4 279.4 279.4 279.4 279.4 279.4 279.4 279.4 279.4 279.4 - - - - Less Smelting, refining & transportation $m (24.3) (22.8) (21.6) (21.2) (21.2) (21.1) (21.2) (22.1) (21.6) (21.9) (21.6) (21.2) (21.5) (21.8) (21.3) (20.8) (21.8) (22.5) (21.3) (21.6) (21.5) (21.2) (20.8) (21.3) (21.6) (21.7) (21.8) (21.7) (20.2) (19.6) (22.1) (30.9) (40.3) (40.4) (46.9) (45.6) (45.6) (45.6) (45.6) (45.6) - - - - Net Smelting Returns $m 288.0 290.7 290.2 289.7 290.5 289.7 290.5 288.8 290.0 288.9 290.1 289.7 290.2 289.1 282.6 282.1 288.7 299.9 283.3 282.9 283.8 283.3 285.1 283.1 283.7 282.7 284.2 282.7 263.8 255.9 257.3 248.5 239.1 239.0 232.5 233.8 233.8 233.8 233.8 233.8 - - - - Less Mine operating costs $m (96.4) (98.7) (94.2) (92.7) (94.3) (90.8) (91.1) (87.5) (90.2) (91.2) (94.0) (93.6) (93.8) (93.4) (95.5) (94.6) (94.6) (92.3) (94.7) (93.4) (94.0) (94.4) (95.4) (93.9) (95.1) (93.5) (95.2) (93.5) (92.2) (92.0) (98.2) (96.4) (96.7) (99.2) (98.9) (63.2) (63.1) (64.9) (65.0) (64.9) - - - - Recycling credit - including interest income $m 29.2 27.6 25.4 25.2 24.2 24.3 25.9 30.0 30.7 31.0 29.9 28.0 28.5 30.1 29.8 29.0 30.1 31.9 29.2 30.8 30.3 28.7 26.2 29.3 29.8 30.2 30.4 28.9 26.7 27.2 32.6 49.9 67.6 68.7 81.8 81.8 81.8 81.8 81.8 81.8 - - - - Less Royalties $m (16.5) (16.6) (16.6) (16.6) (16.7) (16.6) (16.7) (16.6) (16.7) (16.6) (16.6) (16.5) (16.6) (16.5) (16.1) (16.1) (16.5) (17.2) (16.2) (16.2) (16.2) (16.2) (16.3) (16.2) (16.2) (16.2) (16.2) (16.1) (15.1) (14.6) (14.7) (14.3) (13.8) (13.8) (13.5) (13.5) (13.5) (13.5) (13.5) (13.5) - - - - Less Production taxes $m (11.0) (11.1) (11.1) (11.1) (11.1) (11.1) (11.1) (11.1) (11.1) (11.1) (11.1) (11.1) (11.1) (11.0) (10.8) (10.8) (11.0) (11.4) (10.8) (10.8) (10.9) (10.8) (10.9) (10.8) (10.8) (10.8) (10.9) (10.8) (10.2) (9.9) (10.0) (9.7) (9.4) (9.4) (9.2) (9.3) (9.3) (9.3) (9.3) (9.3) - - - - Less Insurance $m (3.6) (3.5) (3.4) (3.4) (3.4) (3.4) (3.4) (3.6) (3.6) (3.6) (3.6) (3.5) (3.5) (3.6) (3.6) (3.5) (3.6) (3.6) (3.5) (3.6) (3.6) (3.5) (3.4) (3.5) (3.6) (3.6) (3.6) (3.5) (3.5) (3.5) (3.6) (4.1) (4.7) (4.7) (5.1) (5.1) (5.1) (5.1) (5.1) (5.1) - - - - EBITDA $m 189.7 188.3 190.3 191.1 189.2 192.0 194.1 200.1 199.2 197.4 194.8 193.0 193.7 194.7 186.3 186.0 193.1 207.4 187.3 189.7 189.4 187.0 185.3 188.0 187.8 188.9 188.7 187.6 169.6 163.1 163.4 173.8 182.1 180.5 187.6 224.5 224.7 222.8 222.8 222.8 - - - - Net Income (loss) before income taxes $m 189.7 188.3 190.3 191.1 189.2 192.0 194.1 200.1 199.2 197.4 194.8 193.0 193.7 194.7 186.3 186.0 193.1 207.4 187.3 189.7 189.4 187.0 185.3 188.0 187.8 188.9 188.7 187.6 169.6 163.1 163.4 173.8 182.1 180.5 187.6 224.5 224.7 222.8 222.8 222.8 (12.6) (12.6) (6.3) - Less: Income 25.9% Tax $m (49.1) (48.8) (49.3) (49.5) (49.0) (49.7) (50.3) (51.8) (51.6) (51.1) (50.4) (50.0) (50.2) (50.4) (48.3) (48.2) (50.0) (53.7) (48.5) (49.1) (49.1) (48.4) (48.0) (48.7) (48.6) (48.9) (48.9) (48.6) (43.9) (42.2) (42.3) (45.0) (47.2) (46.7) (48.6) (58.2) (58.2) (57.7) (57.7) (57.7) 3.3 3.3 1.6 - Net Income (loss) $m 140.6 139.5 141.0 141.6 140.2 142.3 143.8 148.2 147.6 146.3 144.3 143.0 143.5 144.3 138.1 137.8 143.1 153.7 138.8 140.6 140.4 138.6 137.3 139.3 139.2 140.0 139.8 139.0 125.7 120.9 121.1 128.8 134.9 133.7 139.0 166.4 166.5 165.1 165.1 165.1 (9.4) (9.4) (4.7) - Less: Capital expenditures $m (61.8) (59.2) (41.2) (36.8) (33.1) (42.5) (57.6) (42.3) (37.2) (41.2) (35.3) (33.8) (31.2) (31.4) (34.8) (31.9) (37.2) (58.4) (50.0) (51.8) (48.0) (33.9) (28.7) (31.2) (32.4) (29.7) (33.7) (31.8) (30.8) (37.5) (30.0) (35.1) (22.7) (25.8) (34.8) (22.4) 0.0 0.0 0.0 0.0 - - - - Net Cash Flow $m 78.8 80.4 99.8 104.8 107.1 99.8 86.2 106.0 110.4 105.0 109.1 109.1 112.3 112.9 103.2 105.9 105.8 95.3 88.8 88.8 92.3 104.7 108.6 108.1 106.7 110.3 106.2 107.2 94.9 83.4 91.1 93.6 112.2 107.9 104.3 143.9 166.5 165.1 165.1 165.1 (9.4) (9.4) (4.7) - Cumulative Cash Flow $m 78.8 159.2 259.0 363.7 470.8 570.7 656.8 762.8 873.2 978.3 1,087.3 1,196.5 1,308.8 1,421.7 1,524.9 1,630.8 1,736.6 1,831.9 1,920.8 2,009.6 2,101.9 2,206.6 2,315.2 2,423.3 2,530.0 2,640.4 2,746.5 2,853.7 2,948.6 3,032.0 3,123.1 3,216.7 3,329.0 3,436.9 3,541.2 3,685.1 3,851.6 4,016.7 4,181.8 4,346.9 4,337.6 4,328.2 4,323.5 4,323.5 East Boulder After Tax NPV5% $m 1764.3 254 Stillwater Mine 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 Palladium ounces produced 332,926 372,132 440,464 447,966 477,728 474,245 432,292 346,097 334,266 328,684 349,051 385,192 376,465 344,013 342,270 354,886 344,069 324,217 352,772 324,651 334,532 363,888 419,142 350,860 343,172 334,848 333,293 359,626 376,887 355,699 271,486 114,878 37,940 34,429 - - - - - - - - - - Platinum ounces produced 97,309 108,768 128,741 130,933 139,632 138,614 126,352 101,158 97,700 96,069 102,022 112,585 110,035 100,549 100,040 103,728 100,566 94,763 103,110 94,890 97,778 106,358 122,509 102,551 100,304 97,871 97,416 105,113 110,158 103,965 79,351 33,577 11,089 10,063 - - - - - - - - - - Combined ounces produced 430,235 480,900 569,205 578,899 617,360 612,859 558,644 447,255 431,966 424,753 451,073 497,777 486,500 444,562 442,310 458,614 444,635 418,980 455,882 419,541 432,311 470,246 541,651 453,411 443,476 432,718 430,709 464,738 487,045 459,665 350,837 148,455 49,030 44,492 - - - - - - - - - - Palladium revenues 395.3 441.9 523.1 532.0 567.3 563.2 513.3 411.0 396.9 390.3 414.5 457.4 447.1 408.5 406.4 421.4 408.6 385.0 418.9 385.5 397.3 432.1 497.7 416.6 407.5 397.6 395.8 427.1 447.6 422.4 322.4 136.4 45.1 40.9 - - - - - - - - - - Platinum revenues 121.6 136.0 160.9 163.7 174.5 173.3 157.9 126.4 122.0 120.0 127.4 140.6 137.4 125.6 124.9 129.6 125.6 118.4 128.8 118.5 122.1 132.8 153.0 128.1 125.3 122.2 121.7 131.3 137.6 129.9 99.1 41.9 13.9 12.6 - - - - - - - - - - Gross Revenues 517.0 577.9 684.0 695.6 741.8 736.4 671.3 537.4 519.0 510.3 541.9 598.0 584.5 534.1 531.4 551.0 534.2 503.4 547.7 504.0 519.4 565.0 650.7 544.7 532.8 519.9 517.5 558.3 585.1 552.2 421.5 178.4 58.9 53.5 - - - - - - - - - - Smelting, refining & transportation (32.4) (34.2) (37.1) (37.2) (38.0) (38.3) (37.5) (36.1) (35.7) (36.1) (36.2) (36.5) (36.2) (35.8) (36.4) (37.0) (36.0) (35.2) (36.2) (35.8) (36.0) (36.2) (36.8) (36.0) (36.1) (36.1) (36.1) (36.1) (37.1) (36.5) (31.6) (18.7) (7.9) (7.2) - - - - - - - - - - Net Smelting Returns 484.6 543.7 646.9 658.5 703.9 698.2 633.8 501.3 483.3 474.2 505.7 561.5 548.3 498.3 495.0 514.0 498.2 468.2 511.5 468.2 483.4 528.8 614.0 508.8 496.7 483.8 481.4 522.2 548.1 515.7 389.9 159.7 51.0 46.2 - - - - - - - - - - Mine operating costs (188.8) (198.7) (234.8) (229.9) (215.9) (226.8) (229.6) (234.0) (242.8) (245.4) (244.2) (239.3) (252.3) (264.7) (271.1) (275.2) (281.4) (293.7) (287.8) (295.8) (296.3) (267.1) (233.3) (231.4) (231.3) (230.0) (230.6) (227.2) (225.1) (228.0) (194.0) (120.7) (83.6) (82.1) - - - - - - - - - - Recycling credit - including interest income 48.4 50.9 55.8 56.5 57.6 57.5 55.9 51.8 51.1 50.8 51.9 53.8 53.3 51.7 52.0 52.8 51.7 49.9 52.6 51.0 51.5 53.2 55.6 52.5 52.0 51.6 51.4 52.9 55.1 54.6 49.2 31.9 14.2 13.1 - - - - - - - - - - Royalties (22.2) (24.8) (29.6) (30.1) (32.2) (31.8) (28.9) (22.9) (22.1) (21.7) (23.1) (25.6) (25.0) (22.8) (22.6) (23.4) (22.7) (21.3) (23.3) (21.3) (22.0) (24.1) (28.0) (23.2) (22.7) (22.2) (22.0) (23.9) (25.0) (23.6) (17.9) (7.3) (2.3) (2.1) - - - - - - - - - - Production taxes (19.4) (21.4) (24.9) (25.3) (26.9) (26.6) (24.4) (19.9) (19.3) (19.0) (20.1) (21.9) (21.5) (19.8) (19.7) (20.3) (19.8) (18.7) (20.2) (18.7) (19.3) (20.8) (23.7) (20.1) (19.8) (19.4) (19.3) (20.6) (21.5) (20.4) (16.1) (8.2) (4.5) (4.3) - - - - - - - - - - Insurance (6.1) (6.2) (6.2) (6.3) (6.3) (6.3) (6.2) (6.1) (6.1) (6.1) (6.1) (6.2) (6.2) (6.1) (6.1) (6.1) (6.1) (6.1) (6.1) (6.1) (6.1) (6.2) (6.2) (6.1) (6.1) (6.1) (6.1) (6.2) (6.2) (6.2) (6.0) (5.5) (5.0) (5.0) - - - - - - - - - - EBITDA 296.6 343.6 407.1 423.3 480.2 464.2 400.5 270.2 244.1 232.8 264.2 322.3 296.7 236.7 227.6 241.6 220.0 178.2 226.6 177.3 191.2 263.9 378.3 280.4 268.7 257.8 254.8 297.3 325.2 292.1 205.1 49.8 (30.2) (34.1) - - - - - - - - - - Net Income (loss) before income taxes $m 296.6 343.6 407.1 423.3 480.2 464.2 400.5 270.2 244.1 232.8 264.2 322.3 296.7 236.7 227.6 241.6 220.0 178.2 226.6 177.3 191.2 263.9 378.3 280.4 268.7 257.8 254.8 297.3 325.2 292.1 205.1 49.8 (30.2) (34.1) (14.7) (14.7) (7.3) - - - - - - - Less: Income 25.9% Tax $m (76.8) (89.0) (105.4) (109.6) (124.4) (120.2) (103.7) (70.0) (63.2) (60.3) (68.4) (83.5) (76.8) (61.3) (58.9) (62.6) (57.0) (46.1) (58.7) (45.9) (49.5) (68.3) (98.0) (72.6) (69.6) (66.8) (66.0) (77.0) (84.2) (75.7) (53.1) (12.9) 7.8 8.8 3.8 3.8 1.9 - - - - - - - Net Income (loss) $m 219.8 254.6 301.7 313.7 355.9 343.9 296.8 200.2 180.9 172.5 195.8 238.8 219.8 175.4 168.6 179.1 163.0 132.0 167.9 131.4 141.7 195.5 280.3 207.8 199.1 191.0 188.8 220.3 241.0 216.5 152.0 36.9 (22.4) (25.3) (10.9) (10.9) (5.4) - - - - - - - Less: Capital expenditures $m (329.7) (366.4) (210.3) (164.6) (178.9) (110.2) (120.4) (103.2) (104.2) (130.4) (100.1) (103.0) (95.6) (76.5) (76.7) (66.1) (63.7) (38.2) (38.8) (46.6) (53.3) (55.7) (37.1) (28.6) (34.6) (28.3) (35.0) - - - - - - - - - - - - - - - - - Net Cash Flow $m (109.9) (111.9) 91.4 149.1 176.9 233.8 176.4 97.0 76.7 42.1 95.7 135.8 124.2 98.9 92.0 113.0 99.3 93.9 129.1 84.7 88.4 139.8 243.2 179.2 164.5 162.7 153.8 220.3 241.0 216.5 152.0 36.9 (22.4) (25.3) (10.9) (10.9) (5.4) - - - - - - - Cumulative Cash Flow $m (109.9) (221.8) (130.4) 18.7 195.7 429.4 605.8 702.8 779.6 821.7 917.4 1,053.2 1,177.4 1,276.3 1,368.2 1,481.2 1,580.5 1,674.4 1,803.5 1,888.2 1,976.6 2,116.5 2,359.7 2,538.9 2,703.4 2,866.1 3,019.9 3,240.2 3,481.2 3,697.6 3,849.6 3,886.5 3,864.1 3,838.8 3,827.9 3,817.1 3,811.6 3,811.6 3,811.6 3,811.6 3,811.6 3,811.6 3,811.6 3,811.6 Stillwater After Tax NPV5% $m 1625.5 255 Combined Mines 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 Palladium ounces produced 534,916 574,906 642,130 649,080 679,393 675,360 633,958 547,211 535,931 529,799 550,753 586,343 578,167 545,164 538,898 550,845 544,963 532,794 549,831 521,654 532,075 560,890 617,102 547,863 540,715 531,850 531,252 556,628 560,647 533,986 452,274 295,666 218,728 215,217 180,788 180,788 180,788 180,788 180,788 180,788 - - - - Platinum ounces produced 155,201 166,885 186,539 188,574 197,431 196,255 184,151 158,799 155,499 153,710 159,831 170,237 167,844 158,201 156,395 159,891 158,143 154,543 159,588 151,353 154,395 162,821 179,245 159,013 156,921 154,333 154,153 161,575 162,825 155,063 131,166 85,392 62,904 61,878 51,815 51,815 51,815 51,815 51,815 51,815 - - - - Combined ounces produced 690,117 741,790 828,669 837,654 876,824 871,615 818,108 706,011 691,431 683,509 710,585 756,580 746,011 703,365 695,293 710,736 703,106 687,337 709,419 673,006 686,470 723,711 796,347 706,876 697,636 686,183 685,404 718,203 723,472 689,049 583,440 381,058 281,633 277,095 232,603 232,603 232,603 232,603 232,603 232,603 - - - - Palladium revenues 635.2 682.7 762.5 770.8 806.8 802.0 752.8 649.8 636.4 629.1 654.0 696.3 686.6 647.4 639.9 654.1 647.1 632.7 652.9 619.5 631.8 666.1 732.8 650.6 642.1 631.6 630.9 661.0 665.8 634.1 537.1 351.1 259.7 255.6 214.7 214.7 214.7 214.7 214.7 214.7 - - - - Platinum revenues 194.0 208.6 233.2 235.7 246.8 245.3 230.2 198.5 194.2 192.0 199.6 212.6 209.6 197.6 195.3 199.7 197.5 193.0 199.3 189.0 192.8 203.4 223.9 198.6 196.0 192.8 192.5 201.8 203.4 193.7 163.8 106.7 78.6 77.3 64.7 64.7 64.7 64.7 64.7 64.7 - - - - Gross Revenues 829.2 891.3 995.7 1,006.5 1,053.6 1,047.3 983.0 848.3 830.6 821.1 853.6 908.9 896.2 845.0 835.3 853.8 844.7 825.7 852.2 808.5 824.7 869.4 956.7 849.2 838.1 824.3 823.4 862.8 869.1 827.8 700.9 457.8 338.3 332.9 279.4 279.4 279.4 279.4 279.4 279.4 - - - - Smelting, refining & transportation (56.6) (56.9) (58.6) (58.4) (59.2) (59.4) (58.7) (58.2) (57.3) (58.0) (57.9) (57.7) (57.7) (57.6) (57.6) (57.8) (57.8) (57.6) (57.4) (57.4) (57.5) (57.4) (57.6) (57.3) (57.8) (57.8) (57.9) (57.8) (57.3) (56.1) (53.6) (49.6) (48.2) (47.7) (46.9) (45.6) (45.6) (45.6) (45.6) (45.6) - - - - Net Smelting Returns 772.6 834.4 937.1 948.1 994.4 987.9 924.3 790.1 773.3 763.1 795.8 851.2 838.5 787.4 777.6 796.0 786.8 768.1 794.8 751.1 767.2 812.1 899.1 791.9 780.3 766.5 765.5 805.0 811.9 771.6 647.3 408.1 290.1 285.2 232.5 233.8 233.8 233.8 233.8 233.8 - - - - Mine operating costs (285.3) (297.5) (329.0) (322.5) (310.2) (317.6) (320.7) (321.5) (332.9) (336.6) (338.2) (332.9) (346.1) (358.1) (366.7) (369.8) (375.9) (386.0) (382.5) (389.2) (390.4) (361.4) (328.8) (325.3) (326.3) (323.4) (325.8) (320.8) (317.3) (320.0) (292.2) (217.1) (180.3) (181.3) (98.9) (63.2) (63.1) (64.9) (65.0) (64.9) - - - - Recycling credit - including interest income 77.7 78.6 81.2 81.7 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 81.8 - - - - Royalties (38.6) (41.5) (46.2) (46.7) (48.8) (48.5) (45.6) (39.5) (38.7) (38.3) (39.7) (42.1) (41.6) (39.3) (38.7) (39.5) (39.2) (38.5) (39.5) (37.5) (38.2) (40.2) (44.2) (39.4) (38.9) (38.3) (38.3) (40.0) (40.1) (38.2) (32.6) (21.7) (16.2) (15.9) (13.5) (13.5) (13.5) (13.5) (13.5) (13.5) - - - - Production taxes (30.4) (32.5) (36.0) (36.5) (38.0) (37.7) (35.6) (31.0) (30.4) (30.1) (31.1) (33.0) (32.6) (30.8) (30.5) (31.1) (30.8) (30.1) (31.0) (29.6) (30.1) (31.6) (34.6) (31.0) (30.6) (30.2) (30.1) (31.5) (31.7) (30.3) (26.1) (18.0) (13.9) (13.7) (9.2) (9.3) (9.3) (9.3) (9.3) (9.3) - - - - Insurance (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (9.7) (5.1) (5.1) (5.1) (5.1) (5.1) (5.1) - - - - EBITDA 486.3 531.9 597.4 614.4 669.4 656.2 594.5 470.2 443.3 430.2 459.0 515.3 490.3 431.4 413.9 427.6 413.0 385.5 414.0 367.0 380.6 450.9 563.6 468.4 456.5 446.7 443.5 484.9 494.8 455.2 368.5 223.6 151.9 146.4 187.6 224.5 224.7 222.8 222.8 222.8 - - - - Net Income (loss) before income taxes $m 486.3 531.9 597.4 614.4 669.4 656.2 594.5 470.2 443.3 430.2 459.0 515.3 490.3 431.4 413.9 427.6 413.0 385.5 414.0 367.0 380.6 450.9 563.6 468.4 456.5 446.7 443.5 484.9 494.8 455.2 368.5 223.6 151.9 146.4 172.9 209.9 217.4 222.8 222.8 222.8 (12.6) (12.6) (6.3) - Less: Income 25.9% Tax $m (126.0) (137.8) (154.7) (159.1) (173.4) (170.0) (154.0) (121.8) (114.8) (111.4) (118.9) (133.5) (127.0) (111.7) (107.2) (110.8) (107.0) (99.9) (107.2) (95.1) (98.6) (116.8) (146.0) (121.3) (118.2) (115.7) (114.9) (125.6) (128.2) (117.9) (95.4) (57.9) (39.3) (37.9) (44.8) (54.4) (56.3) (57.7) (57.7) (57.7) 3.3 3.3 1.6 - Net Income (loss) $m 360.4 394.1 442.6 455.3 496.1 486.2 440.6 348.4 328.5 318.8 340.1 381.8 363.3 319.6 306.7 316.9 306.1 285.7 306.7 271.9 282.1 334.1 417.6 347.1 338.3 331.0 328.6 359.3 366.7 337.3 273.1 165.7 112.5 108.5 128.1 155.5 161.1 165.1 165.1 165.1 (9.4) (9.4) (4.7) - Less: Capital expenditures $m (391.5) (425.6) (251.4) (201.4) (212.0) (152.7) (178.0) (145.4) (141.3) (171.7) (135.3) (136.9) (126.8) (107.8) (111.5) (98.0) (100.9) (96.5) (88.8) (98.4) (101.3) (89.6) (65.8) (59.8) (67.0) (58.0) (68.6) (31.8) (30.8) (37.5) (30.0) (35.1) (22.7) (25.8) (34.8) (22.4) 0.0 0.0 0.0 0.0 - - - - Net Cash Flow $m (31.1) (31.5) 191.2 253.9 284.0 333.6 262.5 203.0 187.2 147.1 204.8 244.9 236.5 211.8 195.2 218.9 205.1 189.2 217.9 173.5 180.8 244.6 351.8 287.3 271.3 273.0 260.0 327.5 335.9 299.8 243.1 130.5 89.8 82.7 93.4 133.1 161.1 165.1 165.1 165.1 (9.4) (9.4) (4.7) - Cumulative Cash Flow $m (31.1) (62.6) 128.6 382.5 666.5 1,000.1 1,262.6 1,465.6 1,652.8 1,800.0 2,004.7 2,249.7 2,486.2 2,698.0 2,893.1 3,112.0 3,317.1 3,506.3 3,724.2 3,897.8 4,078.5 4,323.1 4,674.9 4,962.2 5,233.4 5,506.5 5,766.4 6,093.9 6,429.8 6,729.6 6,972.7 7,103.2 7,193.0 7,275.7 7,369.1 7,502.2 7,663.2 7,828.3 7,993.4 8,158.6 8,149.2 8,139.9 8,135.2 8,135.2 Combined After Tax NPV5% $m 3389.7
256 Net Present Values The post-tax cash flows for Stillwater and East Boulder Mines derive the DCF results (NPV@5%) contained in Table 64, which illustrate the discount rate sensitivity of these mines and the overall Sibanye-Stillwater US PGM Operations. Table 64: Net Present Values at Different Discount Rates Mineral Asset Units Real Discount Rate 0.00% 2.50% 5.00% 7.50% East Boulder Mine NPV$ million $4 324 $2 639 $1 764 $1 272 Stillwater Mine NPV $ million $3 812 $2 429 $1 625 $1 137 Sibanye-Stillwater US PGM Operations NPV $ million $8 162 $5 079 $3 394 $2 411 Internal Rate of Return The Internal Rate of Return (IRR) of the Sibanye-Stillwater US PGM Operations is 182%. Sensitivity Analysis Sensitivity analyses of the NPVs at the real discount rate of 5% (NPV5%) for variation in grade, revenue, capital and operating costs in the range ±10% for Stillwater and East Boulder Mines are illustrated in Figure 70 and Figure 71, respectively. In each case, the NPV result is most sensitive to revenue and less sensitive to operating cost and capital cost variation. Figure 70: Stillwater Mine NPV Sensitivity Analysis $ 500 $ 700 $ 900 $ 1,100 $ 1,300 $ 1,500 $ 1,700 $ 1,900 $ 2,100 $ 2,300 $ 2,500 -10% -5% 0% 5% 10% << Variance from Base Case >> NPV 5% $m Palladium Price Palladium Grade Platinum Price Platinum Grade Capital Opex 257 Figure 71: East Boulder Mine NPV Sensitivity Analysis For the combined Sibanye-Stillwater US PGM Operations, the two-variable sensitivity analysis of the NPV5% to variance in both palladium and platinum price has been completed (with reference to Error! Reference source not found.). These results are illustrated in Table 65. Table 65: Combined Sibanye-Stillwater US PGM Operations, NPV5% Sensitivity to Pd and Pt Price Variation NPV5% $million Palladium Price Variance from Base Assumption Variance -10% -5% 0% 5% 10% Platinum Price Variance from Base Assumption -10% $2 327 $2 736 $3 145 $3 554 $3 962 -5% $2 452 $2 861 $3 270 $3 678 $4 087 0% $2 577 $2 986 $3 394 $3 803 $4 212 5% $2 702 $3 111 $3 519 $3 928 $4 337 10% $2 827 $3 235 $3 644 $4 053 $4 462 The foregoing sensitivity analysis demonstrates robust results over material technical and economic input range variances and at a range of discount rates. This is considered a reasonable and realistic test of economic viability of the LoM plans for Stillwater and East Boulder Mines and the consolidated LoM plan for the Sibanye-Stillwater US PGM Operations. Accordingly, extraction of the scheduled Indicated and Measured Mineral Resources is economically justified while the declaration of Mineral Reserves for Stillwater and East Boulder Mines is appropriate. $ 500 $ 700 $ 900 $ 1,100 $ 1,300 $ 1,500 $ 1,700 $ 1,900 $ 2,100 $ 2,300 $ 2,500 -10% -5% 0% 5% 10% << Variance from Base Case >> NPV 5% $m Palladium Price PalladiATm Grade Platinum Price PlatinATm Grade Capital Opex 258 OTHER RELEVANT DATA AND INFORMATION Catalytic Converter Recycling Business Background As part of the smelting and refining operations, the Sibanye-Stillwater US PGM Operations include a recycling facility for spent automotive catalytic converters at the Columbus Metallurgical Complex. The recycle business is operated on both toll and outright purchase bases dependant on prevailing market conditions. However, under these scenarios, accurate sampling and analysis is critical to the business. The recycled catalytic converters are added to the concentrate from the mines in the electric arc furnace and the contained PGMs are recovered using the copper and nickel in the mine concentrate as collectors. The format of the catalytic converters varies with the origin of the supply. The European market has mostly diesel vehicles which use a silicon carbide substrate and recycle material from this area tend to be higher in carbon content. However, the North American market tends to supply an exclusively palladium containing recycle material. Carbon and silicon carbide are problematic to the smelting process dependant on the levels contained and, therefore, are measured and managed accordingly. Recycle Processing The recycle materials are delivered in bulk bags with a mass and chemical analysis per bag from the supplier but the official mass and analytical measurements are performed by Sibanye-Stillwater US PGM Operations. The bags are stored until the furnace feed recipe allows for processing (based on the contained carbon) and then delivered into the process via the sampling plant. The bags are weighed, and the contents introduced into the sampling plant which produces a bulk sample equivalent to approximately 1.6% of the bulk mass which is then further reduced to produce the final samples for the laboratory analysis. Samples received are ground in a fully automated grinding and blending machine (HPM1500), analysed for carbon using a Leco™ analyser and pulverised. Carbon analysis is performed ahead of any other analysis to ensure that the process critical carbon levels are in line with the levels reported by the customer. This carbon analysis is used to inform the blending and processing of recycle materials to ensure excess carbon is not added into the smelting process. The pulverised material is subjected to preliminary XRF analysis then dual analysis through XRF (Panalytical Energy Dispersive XRF) and PbFA and ICP-OES. The sampled and crushed recycle materials are introduced into the smelting process via a dedicated hopper in the batching plant and are then blended into the primary furnace feed via the computer control system. The copper and nickel in the matte from the mine concentrates act as a collector for the Pd and Pt present in the smelter feed stream originating from both mine concentrates and recycle materials. As such, it is critical that the recycle materials are balanced with the mine concentrates to ensure sufficient collection capacity for the total PGM loading delivered. 259 Recycling Operations The catalyst recycling business forms an integral part of the Columbus Metallurgical Complex processing feedstock but is not relevant to the declaration of Mineral Reserves for Stillwater and East Boulder Mines. However, revenue credits from the recycling business and by-products often exceed the operating cost for the smelting and refining operations, which underscores the importance of these two additional revenue sources to the value of the Sibanye-Stillwater US PGM Operations.
260 INTEPRETATION AND CONCLUSIONS The Sibanye-Stillwater US PGM Operations are well-established mining, ore processing and mineral beneficiation operations located in Montana and producing PGMs from the extraction of the J-M Reef, which is the highest-grade PGM deposit known to exist in the world. Sibanye-Stillwater has title (leased or held Mining Claims) in perpetuity over the entirety of the known outcrop of the J-M Reef along the Beartooth Mountains in Montana. It also holds surface rights (Tunnel and Mill Site Claims) over key land parcels on which mining infrastructure is built both at Stillwater and East Boulder Mines, with the mining complexes comprising underground mining and integrated ore processing infrastructure. The surface rights also provide servitude required to access the reef or to establish and connect surface infrastructure. A network comprising state roads and a Sibanye-Stillwater maintained road connects the mines, local towns and the Columbus Metallurgical Complex where the smelter, base metal refinery, laboratory and PGM catalyst recycling plant are situated. Regional power infrastructure is already installed providing adequate power supplies to the operations. Climatic conditions in this area do not significantly affect the operations. Whereas the regulatory framework for mining provides for a simplified system for obtaining and maintaining mining and surface title, the granting of permits and approvals for building a mine or expansions to existing mining operations is costly and can be a lengthy process. The 20-year-old Good Neighbor Agreement between Sibanye-Stillwater and the local authorities has facilitated seamless stakeholder participation in the scoping and review of applications for permits and approvals. Extensive exploration work spanning several decades and dominated by diamond drilling at Stillwater and East Boulder Mines produced data utilised for the evaluation of the J-M Reef. The J-M Reef is a world class magmatic reef-type PGM deposit in the geologically favourable Stillwater Complex. The extensive drillhole database accumulated from moderately spaced surface diamond drilling and closely spaced underground definition diamond drilling from footwall lateral drifts, complemented by mining and ore processing information, has confirmed the presence and character of the Pd-Pt dominant mineralisation in the J-M Reef. The drilling strategy adopted is a consequence of the rugged terrain characterising the Beartooth Mountain area, the steep dips of the J-M Reef and high localised variability in the J-M Reef. The approaches employed for the collection, validation, processing and interpretation of drillhole data are in line with industry best practice. The extensive validated drillhole database forms the basis for the Mineral Resource estimates reported for Stillwater and East Boulder Mines. A combination of long-range continuity, occurrence at a consistent stratigraphic position and within a consistent stratigraphic sequence, localised thickness and grade variability and steep dips influences the drilling strategy and estimation approaches employed for the J-M Reef. Available data permitted the construction of 3D geological models and estimation of grades in areas supported by surface exploration and definition drillhole data classified as Measured and the remainder of the areas supported by surface drillhole data classified as Indicated or Inferred. The estimation approaches are appropriate for the style and variability of the J-M Reef. The reporting of the Mineral Resources at the minimum mining width of 7.5ft based on the dominant Ramp and Fill method used and 2E cut-off grade of 0.20opt (6.86g/t) at Stillwater Mine and 0.05opt (1.71g/t) at East Boulder Mine is well-reasoned. For consistency, lowering of the 2E cut-off grade used for Mineral Resource reporting at Stillwater Mine to 0.05opt is recommended. 261 Detailed LoM plans for Stillwater and East Boulder Mines support the Mineral Reserve estimates reported by Sibanye-Stillwater for the Sibanye-Stillwater US PGM Operations. Modifying factors derived through reconciliation at the mines have been utilised for the conversion of Indicated and Measured Mineral Resources to Probable and Proven Mineral Reserves, respectively. The Ramp and Fill method, which is the dominant mining method, is well-understood at the mines and suited to the character and attitude of the J-M Reef. Mine designs for Stillwater and East Boulder Mines incorporate the hydrogeological and geotechnical models constructed from groundwater and geotechnical testwork, an extensive geotechnical database and historical experience at the mines. Ground support designs and procedures employed at the mines, which have been refined through ongoing continuous improvement initiatives, have eliminated occurrences of major fall of ground occurrences. No significant groundwater inflows are experienced except when development extends into new areas, but these are addressed using existing procedures combining probe drilling, the use of drainholes and routine mine dewatering using cascading water pumps. The LoM production plans for Stillwater and East Boulder Mines were developed through and Mineral Resources to Mineral Reserve conversion process, which utilised dilution factors and mining parameters informed by historical reconciliation results and performance. The use of factors aligned to historical performance enhances the achievability of the plans. The LoM plans envisage an important ore production tonnage ramp up at Stillwater Mine associated with the Stillwater East Section and steady state operations at East Boulder Mine following conclusion of the Fill The Mill Project. The LoM plans were subjected to economic viability testing to demonstrate that extraction of the scheduled Indicated and Measured Mineral Resources is economically justified. Furthermore, most of the key infrastructure for mining is already installed at the Stillwater and East Boulder Mines. Limited additional infrastructure required for the expanded operations at both sites is at an advanced stage of installation. Similarly, most of the mining equipment required for the execution of the plans is already at the mines, with additional equipment required at Stillwater Mine already purchased and awaiting delivery. Bulk power and water supplies are secure, and the infrastructure upgrades required have been completed ahead of the achievement of steady state production levels. The concentrators employed for ore processing at the Stillwater and East Boulder Mines have been operational for several decades and use proven technology and process routes. Furthermore, the forecast metallurgical recoveries and production profiles employed in the LoM plans are informed by historical experience. A plant capacity upgrade is under way at Stillwater Mine to accommodate increasing RoM ore production from the Stillwater East Section. The LoM plan for East Boulder Mine envisages sustained full utilisation, which was historically operated below capacity, in line with the Fill The Mill Project objectives. There is adequate storage capacity for the tailings resulting from ore processing at the concentrators at both Stillwater and East Boulder Mines in the short to medium term. However, additional tailings storage capacity will be required for the remainder of the LoMs. Plans being considered for the upgrading the TSF capacities for the long-term disposal of the tailings include storage capacity upgrades at existing TSFs through elevation lifts and lateral expansions as well as the establishment of 262 new TSFs. Sibanye-Stillwater is aware of the long timeframes for the granting of permits and related approvals of the upgrades and establishment of new TSFs. As a result, it will expedite the finalisation of the long-term tailings storage plans required to enable the undertaking of the requisite studies needed for permit and approval applications. The smelter and base metal refinery at the Columbus Metallurgical Complex utilise proven technology and process routes for the processing of concentrate and matte, respectively. There are no plans to introduce new processing technology at the processing facilities. Modest capacity upgrades and debottlenecking projects implemented to accommodate increased concentrate production from the Stillwater and East Boulder Mines are being concluded. The LoM plans for Stillwater and East Boulder Mines and the Columbus Metallurgical Complex provide for appropriate capital expenditure budgets for the sustainability of the operations and for the various capacity upgrades and production expansions envisaged. Sustaining capital costs are benchmarked to historical capital expenditure. Similarly, the forecast operating costs included in the LoM plans are based on actual costs at the operations, with adjustments made for escalation as required. The importance of the catalyst recycling business and by-products to the Sibanye-Stillwater US PGM Operations is manifested by revenue credits from these sources that often exceed the operating cost for the smelting and refining operations at the Columbus Metallurgical Complex. However, the recycling business and the by-products are excluded from the Mineral Resources and Mineral Reserves for Stillwater and East Boulder Mines. Sibanye-Stillwater has all necessary rights and approvals to operate the mines, concentrators, TSFs, waste rock storage dumps, smelter and ancillary facilities associated with the Sibanye-Stillwater US PGM Operations. Appropriate additional studies, designs and permitting documents have been or are in the process of being completed to support the planned operational expansions. Current permit and license violations are being corrected and environmental impacts are being managed in close consultation with the appropriate agencies. There are reasonable prospects that the operator’s licence to operate on these premises is secure for the foreseeable future, unless terminated by regulatory authorities for other reasons. Bonding amounts are deemed reasonable and appropriate for the permitted activities and obligations at both Stillwater and East Boulder Mines, contingent to final resolution of the Stillwater Mine bond negotiations with the regulatory authorities. Furthermore, based on assessment of the current permits, technical submittals, regulatory requirements and project compliance history, continued acquisition of permit approvals should be possible and there is low risk of rejections of permit applications by the regulatory for the foreseeable future. The market fundamentals for palladium and platinum are forecast to remain in place in the foreseeable future and the price forecasts and other economic assumptions utilised for economic viability testing of the LoM plans are reasonable. 263 The Qualified Persons could not identify any material risks that would affect the Mineral Resources and Mineral Reserves reported for Stillwater and East Boulder Mines. Most of the issues identified are low to medium risks which include the following: • Inadequate tailings storage capacity in the long term due to permitting delays; • Power losses due to inclement weather; • Unplanned production cost escalation; • Failure to effectively execute the LoM plan; • Higher groundwater inflows than experienced previously at the mines; and • Excavation failure due to geotechnical conditions never experienced previously. Sibanye-Stillwater is fully aware of the low to medium risks identified and have mitigation measures in place to minimise the impact of the risks on the mining, ore processing and mineral beneficiation operations in Montana.
264 RECOMMENDATIONS There are no specific recommendations for additional work at Stillwater and East Boulder Mines or the Columbus Metallurgical Complex. The geological models and LoM plans for the operations will be updated and refined as new information becomes available. Most of the costs associated with the generation of new data and updates of the geological models and LoM plans as well as Mineral Resource and Mineral Reserve estimates are accounted for in the capital and operating cost budgets. The Qualified Persons do not anticipate significant additional costs for the undertaking of this work. 265 QUALIFIED PERSONS’ CONSENT AND SIGN-OFF 266 REFERENCES Blakely, R.J., and Zientek, M.L., 1985. Magnetic anomalies over a mafic intrusion: The Stillwater Complex. The Stillwater Complex, Montana Bureau of Mines and Geology, Special Publication 92, 2002 reprint. Czamanske, G.K., and Zientek, M.L. eds. Boudreau, A., 1999. Fluid Fluxing of Cumulates: the J-M Reef and Associated Rocks of the Stillwater Complex, Montana, Journal of Petrology, Volume 40, pp 755-772. DEQ and USFS, 1985. Montana Department of Environmental Quality and U.S Forest Service. Final Environmental Impact Statement, Stillwater Project, December, 1985. DEQ and USFS, 2012. Final Environmental Impact Statement, Stillwater Mining Company's Water Management Plans and Boe Ranch LAD, May 2012. DEQ and USFS, 2012a. Record of Decision for Stillwater Mining Company's Revised Water Management Plans and Boe Ranch LAD, Stillwater and Sweet Grass Counties, Montana (July 2012). DEQ and USFS, 2020. Draft Environmental Assessment East Boulder Mine Stage 6 Tailings Storage Facility Expansion Project, May 2020. DEQ, 2001. Montana Department of Environmental Quality Bonding Procedure Manual. 2001. Kleinkopf, D.M., 1985. Regional gravity and magnetic anomalies of the Stillwater Complex area. The Stillwater Complex, Montana Bureau of Mines and Geology, Special Publication 92, 2002 reprint. Czamanske, G.K., and Zientek, M.L. eds. McCallum, I.S., 2002. The Stillwater Complex: A review of the geology. In: Boudreau, A.E., (ed.). Stillwater Complex, Geology and Guide. Billings, 21-25 July 2002, 9th International Platinum Symposium, A1-25. Page, N.J., and Zientek, M.L., 1985. Geologic and structural setting of the Stillwater Complex. The Stillwater Complex, Montana Bureau of Mines and Geology, Special Publication 92, 2002 reprint. Czamanske, G.K., and Zientek, M.L. eds. Stillwater Mining Company, Northern Plains Resource Council, Cottonwood Resource Council, Stillwater Protective Association, 2014. Good Neighbor Agreement. Amended December 8, 2014. Zientek, M.L., Czamanske, G.K., and Irvine, N.T., 1985. Stratigraphy and nomenclature for the Stillwater Complex. The Stillwater Complex, Montana Bureau of Mines and Geology, Special Publication 92, 2002 reprint. Czamanske, G.K., and Zientek, M.L. eds.
Keliber Lithium Project, Finland Technical Report Summary Prepared for Sibanye Stillwater Limited Report Number 592138 Report Prepared by SRK Consulting (South Africa) (Pty) Ltd Report Date: 13 December 2023 (Effective Date: 31 December 2022) [§229.1302(b)(1); §229.1302(b)(4)(iv)] SRK Consulting – 592138 SSW Keliber TRS Page i SRK SSW_Keliber Project TRS_Final 13 December 2023 Report Date: 13 December 2023 Effective Date:31 December 2022 Keliber Lithium Project, Finland Technical Report Summary Prepared for Sibanye-Stillwater Limited Bridgeview House. Building 11, Constantia Office Park Cnr 14th Ave and Hendrik Potgieter Road Weltevreden Park 1790 Compiled by SRK Consulting South Africa (Pty) Ltd 265 Oxford Road Illovo Johannesburg 2196 South Africa P O Box 55291 Northlands 2116 South Africa Tel: +27 11 441-1111 Fax: +27 86 555 0907 SRK Project Number 592138 Issue Date of TRS: 13 December 2023 (Effective Date of TRS: 31 December 2022) [[§229.1302(b)(1); §229.1302(b)(4)(iv)] SRK Consulting – 592138 SSW Keliber TRS Page ii SRK SSW_Keliber Project TRS_Final 13 December 2023 Report Date: 13 December 2023 Effective Date:31 December 2022 Important Notices In this document, a point is used as the decimal marker and a space is used in the text for the thousand’s separator (for numbers larger than 999). In other words, 10 148.32 denotes ten thousand one hundred and forty-eight point three two. The word ‘tonnes’ denotes a metric tonne (1 000 kg). Wherever mention is made of “Keliber”, for the purposes of this Technical Report Summary (TRS), it encompasses all of the current and planned activities related to the Keliber Lithium Project, in which Sibanye Stillwater Limited owns an 84.96% share, in Central Ostrobothnia, Finland unless specifically mentioned differently. This report includes technical information, which requires subsequent calculations to derive subtotals, totals and weighted averages. Such calculations may involve a degree of rounding and consequently introduce an error. Where such errors occur, SRK does not consider them to be material. The reader and any potential or existing shareholder or investor of Sibanye Stillwater Limited is cautioned that Sibanye Stillwater Limited is involved in exploration on the Keliber Lithium Project and there is no guarantee that any unmodified part of the Mineral Resources will ever be converted into Mineral Reserves nor ultimately extracted at a profit. This report uses a shorthand notation to demonstrate compliance with Subpart 1300 of the United States Securities and Exchange Commission’s Regulation S-K, for example: [[§229.601(b)(96)(iii)(B)(2)] represents sub-section (iii)(B)(2) of section 96 of CFR 229.601(b) (“Item 601 of Regulation S-K”). Description of Amendments to Previously Filed Technical Report Summary This Technical Report Summary (TRS) for the Keliber Lithium Project (Keliber), dated 13 December 2023, serves as an amendment to the TRS prepared by SRK for Keliber for the fiscal year ended 31 December 2022, effective 31 December 2022, which was filed as Exhibit 96.7 to Sibanye-Stillwater Limited’s 2022 annual report filed on Form 20-F on 24 April 2023 (the Original 2022 Keliber TRS). This TRS was prepared by SRK following Sibanye Stillwater Limited’s receipt of comment letters and associated dialogue with the staff (the Staff) of the United States Securities and Exchange Commission (the SEC) regarding information in the Original 2022 Keliber TRS. While this TRS incorporates certain changes to the Original 2022 Keliber TRS, it maintains an effective date of 31 December 2022 with regard to assumptions and the knowledge of the Qualified Persons (QPs). This TRS revises the following information in the Original 2022 Keliber TRS as a result of the comments received from the Staff: The inclusion in Section ES 6 of the Mineral Resource point of reference as in-situ to comply with Item 1303 (b)(3)(v), thus no dilution and other modifying factors are applied to the estimated Mineral Resource. o This change is also added in Section 10. The inclusion in Section ES 9 of the Mineral Reserve point of reference as mill-feed to comply with Item 1303 (b)(3)(v), which include dilution and other modifying factors for the estimated of the Mineral Reserve. o This change is also added in Section 11. Addition of relevant lithium conversions and explanation of such conversions in ES 10, Section 10.2.1 and Section 11.3.1; Addition of conversion matrix in Section 10.2.1 (Table 10-6) Correction to the Total (Mt) and Ore Production (Mt) total of Table 12-2 to reflect only the open pit production salient features per mining area; o Subsequent to the above changes, the stripping ratio and Li2O (%) presented in Table 12-2 were recalculated to also reflect only the open pit Stripping ratio and Li2O (%), which were previously averages for the total tonnes, including underground tonnages, and were not limited to open pit production. SRK Consulting – 592138 SSW Keliber TRS Page iii SRK SSW_Keliber Project TRS_Final 13 December 2023 Report Date: 13 December 2023 Effective Date:31 December 2022 • Inclusion of further information regarding the price and demand of spodumene concentrate in Section 15 of this report, which was derived from the Wood Mackenzie (2021) market study (the “Wood Mackenzie Report”) and Fastmarkets (March 2022) market study (the “Fastmarkets Report”). o The Wood Mackenzie Report and Fastmarkets Report were also added to the list of documents provided by Sibanye in connection with the preparation of the Keliber TRS in section 23.1 and text has been added to reference these market studies in Section 18 of this report. • Removed Table 18-2 and Table 18-3 and text referencing these tables in Section 18 to comply with Item 1302(e)(3) and 1302(e)(6) of Regulation S-K.
SRK Consulting – 592138 SSW Keliber TRS Page iv SRK SSW_Keliber Project TRS_Final 13 December 2023 Report Date: 13 December 2023 Effective Date:31 December 2022 Executive Summary [§229.601(b)(96)(iii)(B)(1)] ES1: Introduction This Technical Report Summary (TRS) of the Keliber Lithium Project (Keliber) was compiled by SRK Consulting (South Africa) (Pty) Ltd (SRK) on behalf of Sibanye Stillwater Limited (SSW, also referred to as the Company) according to Item 601 of the United States Securities and Exchange Commission’s (SEC’s) Subpart 1300 of Regulation S-K (S-K1300). SSW holds an 84.96% share in the Keliber Lithium Project, which is located in Central Ostrobothnia, Finland, through its 100% interest in Keliber Lithium (Pty) Ltd. Keliber is a combination of two businesses – the mine and the refinery with the concentrator being considered as part of the mine. Both businesses are run as standalone entities. The Mineral Reserves and Mineral Resources can be declared based solely on the economics of the production of concentrate from the mine. The Kokkola lithium hydroxide refinery (Keliber Lithium Refinery) can, similarly, be run profitably when processing third-party concentrates. The Keliber Lithium Refinery is thus not considered a Mineral Asset and discussions in this document include the refinery only because there are synergies, and it is the intention to mostly process own concentrate. This report is the first TRS for SSW’s Keliber Lithium Project and supports the disclosure of Mineral Resources and Mineral Reserves at 31 December 2022. The Mineral Resources and Mineral Reserves have been prepared and reported according to the requirements of S-K1300. ES2: Effective Date [§229.1302(b)(iii)(3)] The effective date of the TRS is 31 December 2022, which satisfies the S-K1300 requirement of a current report. ES3: Property description, Mineral Rights and ownership Keliber is situated in Central Ostrobothnia in western Finland in the municipalities of Kaustinen, Kokkola and Kruunupyy. There are seven elements to the project: • Seven spodumene exploration or mining properties at Syväjärvi, Rapasaari, Länttä, Outovesi, Emmes, Leviäkangas and Tuoreetsaaret; • The Keliber Lithium Concentrator at Päiväneva next to Rapasaari mining property; and • The Keliber Lithium Hydroxide Refinery planned for the Kokkola Industrial Park (KIP). Figure ES. 1 depicts the location of the various project elements. Keliber has applied for a range of permits to facilitate mining. Some of the permits have been approved, others are submitted, and some have been awarded but are under appeal following objections. It is a reasonable assumption that the permits will be awarded, even if with some modified conditions. At present there do not appear to be any environmental or permitting issues that will preclude the declaration of Mineral Resources or Mineral Reserves. While the time required for the authorities to process applications is uncertain and may defer project development if these applications are delayed, there is a reasonable expectation that all the required permits can be awarded. Keliber has progressed well with the permit applications and has indicated that they are not aware of any incorrect filings or red flags related to submitting applications. The following mineral rights for lithium currently apply: • Two legally valid mining permits (Länttä and Syväjärvi, including the Syväjärvi Auxiliary Area); • One granted mining permit (Rapasaari, under appeal); • Nine valid exploration permits (additional three granted under appeal); and • One reservation permit. In addition, there are three granted exploration permits where the permitting decision has been appealed and is currently under a legal process in an Administrative Court. SRK Consulting – 592138 SSW Keliber TRS Page v SRK SSW_Keliber Project TRS_Final 13 December 2023 Report Date: 13 December 2023 Effective Date:31 December 2022 Nine exploration permits are valid until expiry dates ranging from January 2023 to September 2025. Application for a further 28 exploration permits was made between 2018 and 2022; these are awaiting finalisation. The various permits and applications are summarized in Table ES- 1 and Table ES- 2 and depicted in Figure ES. 2. Keliber owns land at both Syväjärvi (47.39 ha (~28%) of the current mining area of 166.3 ha) and Outovesi (41.73 ha (~20%) of current claim areas of 209.67 ha). Compensation to the landowners is due on the valid mining and exploration permits, according to the Mining Act (621/2011 as amended). Compensation on the granted exploration permits and the applications will become due once the permits become legally valid. SRK Consulting – 592138 SSW Keliber TRS Page vi SRK SSW_Keliber Project TRS_Final 13 December 2023 Report Date: 13 December 2023 Effective Date:31 December 2022 SSW Keliber Lithium Project Locality plan of the Keliber Lithium Project’s elements (Source: WSP, 2022) Project No. 592138 Figure ES. 1: Locality plan of the Keliber Lithium Project’s elements SRK Consulting – 592138 SSW Keliber TRS Page vii SRK SSW_Keliber Project TRS_Final 13 December 2023 Report Date: 13 December 2023 Effective Date:31 December 2022 Table ES- 1: Summary of mining and exploration permits Number Asset Number Status Decision Date Expiry Date Licence Area (ha) Valid mining permits 1 Länttä 7025 Legally valid 16/08/2016 20/03/2027 37.49 KL2021:0002 11/02/2022 2 Syväjärvi KL2018:0001 Legally valid 13/12/2018 Until further notice 186.25 KL2021:0003 08/02/2022 3 Rapasaari1 KL2019:0004 Granted 23/03/2022 Until further notice 488.98 Total area 712.72 Valid exploration permits 1 Emmes 2 ML2019:0052 Legally valid 30/07/2021 06/09/2024 58.1 2 Karhusaari ML2012:0157 Legally valid 16/12/2019 15/01/2023 167.36 3 Outoleviä ML2019:0011 Legally valid 30/07/2021 06/09/2024 444.65 4 Outovedenneva ML2011:0019 Legally valid 30/07/2021 06/09/2024 68.75 5 Outovesi ML2018:0089 Legally valid 20/03/2020 20/04/2023 144.68 6 Outovesi 3 ML2018:0122 Legally valid 20/03/2020 20/04/2023 12.9 7 Roskakivi ML2016:0020 Legally valid 30/07/2021 06/09/2025 227.18 8 Syväjärvi 3-4 ML2018:0120 Legally valid 16/12/2019 15/01/2023 115.75 9 Timmerpakka ML2019:0010 Legally valid 20/03/2020 20/04/2023 53.68 Total area 1 293.05 Valid Reservation 1 Peräneva VA2022:0020 Reservation 19/05/2022 04/04/2024 3 915.16 Total area 3 915.16 Granted exploration permits (appealed)1 1 Emmes 1 ML2015:0031 Granted 01/11/2021 19.86 2 Haukkapykälikkö ML2011:0002 Granted 30/07/2021 350.32 3 Pässisaarenneva ML2018:0040 Granted 30/07/2021 22.53 Total area 392.71 Note: 1. Permit decision appealed; under legal process in Administrative Court. Table ES- 2: Summary of exploration permit applications Number Asset Number Status Application Date Licence Area (ha) 1 Arkkukivenneva ML2021:0045 Pending 31/03/2021 83.78 2 Buldans ML2020:0001 Pending 16/01/2020 105.57 3 Hassinen ML2018:0034 Pending 02/05/2018 300.39 4 Heikinkangas ML2012:0156 Pending 27/05/2019 42.55 5 Hyttikangas ML2018:0035 Pending 02/05/2018 238.08 6 Kellokallio ML2019:0032 Pending 27/04/2019 182.19 7 Karhusaari ML2012:0157-03 Pending 17/11/2022 137.91 8 Keskusjärvi ML2018:0033 Pending 02/05/2018 211.08 9 Kokkoneva ML2018:0055 Pending 16/05/2018 284.85 10 Länkkyjärvi ML2018:0036 Pending 02/05/2018 361.57 11 Leviäkangas 1 ML2013:0097 Pending 05/05/2021 90.69 12 Matoneva ML2018:0041 Pending 08/05/2018 511.54 13 Orhinselkä ML2018:0042 Pending 08/05/2018 222.05 14 Östersidan ML2018:0056 Pending 16/05/2018 204.95 15 Päiväneva ML2012:0176-03 Pending 19/11/2022 52.02 16 Palojärvi ML2018:0091 Pending 08/10/2018 35.55 17 Paskaharju ML2016:0044 Pending 03/05/2022 131.71 18 Peikkometsä ML2018:0023 Pending 21/03/2018 773.44 19 Peuraneva ML2018:0032 Pending 02/05/2018 152.67 20 Rapasaari ML2018:0121-02 Pending 16/11/2022 64.90 21 Ruskineva ML2020:0002 Pending 17/01/2020 739.35 22 Rytilampi ML2011:0020 Pending 03/02/2018 163.21 23 Syväjärvi 2 ML2016:0001 Pending 07/04/2021 71.53 24 Syväjärvi 3-4 ML2018:0120-02 Pending 17/11/2022 115.75 25 Timmerpakka 2 ML2020:0025 Pending 23/04/2020 174.96 26 Valkiavesi ML2018:0031 Pending 02/05/2018 1 037.56 27 Vanhaneva ML2019:0002 Pending 27/09/2018 368.12 28 Vehkalampi ML2018:0022 Pending 22/03/2018 1 138.54 Total area 5 768.39
SRK Consulting –592138 SSW Keliber TRS Page viii SRK SSW_Keliber Project TRS_Final 13 December 2023 Report Date: 13 December 2023 Effective Date:31 December 2022 SSW Keliber Lithium Project Mining and exploration permits as at 31 December 2022 Project No. 592138 Figure ES. 2: Mining and exploration permits as at 31 December 2022 SRK Consulting – 592138 SSW Keliber TRS Page ix SRK SSW_Keliber Project TRS_Final 13 December 2023 Report Date: 13 December 2023 Effective Date:31 December 2022 ES4: Geology and mineralisation Keliber is located within the Kaustinen Lithium Pegmatite Province that covers an area of 500 km2 in western Finland. Here the host rocks belong to the Palaeoproterozoic (1.95 – 1.88 Ga) age Pohjanmaa Belt that forms a 350 km long by 70 km wide arcuate belt located between the Vaasa Granite Complex to the west and the Central Finland Granitoid Complex to the east. The northern parts of the Pohjanmaa Belt have been intruded by several Lithium-Caesium-Tantalum (LCT) type pegmatites with a majority of those belonging to the Kaustinen lithium province being of the albite/spodumene type. Historical exploration supported by more recent drilling by the Geological Survey of Finland (GTK) and Keliber has (to date) resulted in the delineation of five discrete LCT pegmatite deposits, viz. Syväjärvi, Rapasaari, Länttä, Emmes and Outovesi. Each deposit is characterised by a series of pegmatites, veins and dykes, with intrusion geometry often being controlled by regional structural controls as well as host rock rheology. All of the pegmatites that have been discovered and evaluated to date within the Kaustinen area all have very similar mineralogy in that they are dominated by albite (37 - 41%), quartz (26 – 28%), K-feldspar (10 – 16%), spodumene (10 – 15%) and muscovite (6 - 7%). Spodumene is the only lithium-bearing mineral that is of economic interest and is generally homogeneously distributed throughout most of the pegmatites. Several deposits display frequent inclusion or incorporation of host rock xenoliths within the modelled pegmatites and represent a form of internal dilution to the pegmatites. Rock strength testing Overall, the rock mass quality in the studied areas of the deposit indicate good quality, competent rock as evident from the competent drill core and from competent rock mass on the exposed excavations observed during the site visit at Syväjärvi. The current geotechnical environment at Rapasaari, Syväjärvi and Länttä sites are understood to PFS study level. The intact rock strength parameters for the Syväjärvi site were inferred from those determined from the Rapasaari due to their close proximity to each other in comparison to other mining areas. To date, no oriented geotechnical drilling was done for any of the sites, with geotechnical logging carried out on geology drill core. The available geotechnical data considered during the review, coupled with reported observations on exposed excavations, during the site visit, determine that the level of understanding of the rock strength parameters and characterization is regarded to be appropriate to define the geotechnical environment for Syväjärvi, Länttä and Rapasaari sites to Prefeasibility Study (PFS) study level. However, the geotechnical conditions at the Outovesi deposit are not currently well defined and are considered to be still at conceptual study level due to data scarcity and will need to be appraised to Prefeasibility Feasibility Study (PFS) through to FS level during project implementation. Geotechnical conditions vary across the different sites, with open pit reserves having higher geotechnical data confidence due to existing exposures and laboratory test work. In-fill drilling and the associated testwork should consider further focus on discontinuity strength parameters for further improved geotechnical understanding of site and project specific conditions. It is noted that geotechnical data gathering and modelling are a continuous process during project implementation and mining operations, with confidence in rock mass and structural conditions improving over time as mining continues. ES5: Status of exploration, development and operations Apart from shallow surface reverse circulation drilling completed by GTK over the Syväjärvi deposit, all drilling (Table ES- 3) on the project has been completed using diamond core methods. Diamond core drilling therefore has been the only method used to generate geological, structural and analytical data over the deposits and these have been used as the basis for Mineral Resource estimation over each of the deposits defined to date. SRK Consulting – 592138 SSW Keliber TRS Page x SRK SSW_Keliber Project TRS_Final 13 December 2023 Report Date: 13 December 2023 Effective Date:31 December 2022 Table ES- 3: Drilling completed by historical operators, GTK and Keliber to date Deposit Historical & GTK Keliber Total Number of drill holes Length (m) Number of drill holes Length (m) Number of drill holes Length (m) Syväjärvi 37 4 078 155 16 109 192 20 187 Rapasaari 26 3 653 263 44 482 289 48 135 Länttä 27 2 931 73 6 136 100 9 067 Emmes 84 8 891 23 2 939 107 11 830 Outovesi - - 31 2 613 31 2 613 Tuoreetsaaret - - 50 10 617 50 10 617 Leviäkangas 99 6 821 24 5 174 123 11 994 Total 273 26 374 619 88 069 892 114 443 Since commencement of exploration in the Kaustinen region, Keliber has completed a systematic exploration and Mineral Resource evaluation programme that has been successful in delineating five discrete spodumene- mineralised pegmatite deposits. The work completed to date has captured all the important variables (mineralogical, structural, lithological) required to properly define host pegmatite/s attitude and importantly, spodumene or grade distribution within the various pegmatites that host each deposit. In January 2022, Keliber issued a draft Definitive Feasibility Study (DFS) (WSP Global Inc., 2022c) based on the production of 15 000 tpa of battery-grade lithium hydroxide. This DFS used the DFS issued in February 2019 as basis for most of the technical work. The final DFS was issued on 1st February 2022. SRK reviewed this DFS and classified it as a pre-feasibility study (PFS) in terms of Table 1 to Paragraph (d) in S-K1300 [§229.1302(d)]. This implies Capital Cost Estimate (Capex) and Operating Cost Estimate (Opex) accuracy of ±25% and overall project contingency of ≤15% could be achieved. It should be noted, however, that estimation of capital and operating costs is inherently a forward- looking exercise. These estimates rely upon a range of assumptions and forecasts that are subject to change depending upon macro-economic conditions, operating strategy and new data collected through future operations. Therefore, changes in forward-looking assumptions can result in capital and operating costs that deviate more than 25% from the costs forecast herein. The major reasons for the downgrade of the DFS to PFS level by SRK are as follows: • The mining cost for the February 2022 DFS was derived by escalating the February 2019 DFS’s mining cost by 25%, The RFQ’s were thus not updated for the February 2022 DFS. • Geotechnical test work was not done to DFS level; o Geotechnical drilling and testwork was limited to the Rapaasari mining property; and o Geotechnical data from the Rapasaari deposit was used to infer geotechnical parameters for the other operations. • The Keliber concentrator will make use of XRT ore sorting to remove waste material from mill feed; o This was only tested on Syväjärvi mining property ore material; ▪ The characteristics across the mining property may vary which was not tested; and ▪ The efficiency results from the tests were assumed for the mining properties. • The Market for concentrate of 4.5% Lithium spodumene is unknown as the benchmark is 6% Li2O in Europe. ES6: Mineral Resource estimates The in situ Mineral Resources at 31 December 2022 are summarized in Table ES- 4 on an attributable basis (Sibanye-Stillwater attributable ownership is 84.96%) and are reported exclusive of Mineral Reserves. The Mineral Resources, except for the Emmes deposit, are reported above a cut-off of 0.5% Li2O, with Emmes reported above a cut-off of 0.7 % Li2O. No geological losses are considered in the Mineral Resource reporting. The majority of the declared Mineral Resources are classified as Indicated Mineral Resources (50%) with the remaining split between Measured (8%) at Syväjärvi, Rapasaari and Länttä and Inferred (42%) at Syväjärvi, SRK Consulting – 592138 SSW Keliber TRS Page xi SRK SSW_Keliber Project TRS_Final 13 December 2023 Report Date: 13 December 2023 Effective Date:31 December 2022 Rapasaari, Leviäkangas and Tuoreetsaaret. The majority of the Measured Mineral Resources are converted to Proven Mineral Reserves and are therefore excluded from Table ES- 4. Table ES- 4: Mineral Resource Statement for Keliber Oy operations as at 31 December 2022 Classification Deposit Mass (Mt) Li grade (%) LCE content (kt) Measured Syväjärvi 0.0 0.5 0.9 Rapasaari 0.3 0.5 7.4 Länttä 0.2 0.5 5.2 Total Measured 0.5 0.5 13.5 Indicated Syväjärvi 0.4 0.5 10.7 Rapasaari 1.1 0.4 25.4 Länttä 0.7 0.5 16.7 Outovesi 0.0 0.7 1.2 Emmes 0.9 0.6 27.6 Leviäkangas 0.2 0.5 4.6 Total Indicated 3.3 0.5 86.1 Inferred Syväjärvi 0.1 0.4 2.0 Rapasaari 1.3 0.4 29.3 Leviäkangas 0.2 0.4 5.3 Tuoreetsaaret 1.2 0.3 20.6 Total Inferred 2.8 0.4 57.1 Total Mineral Resources 6.7 0.4 156.7 Notes: 1. Mineral Resources are reported exclusive of Mineral Reserves derived from them. 2. The reference point for Mineral Resources are in -situ material. 3. Mineral Resources are not Mineral Reserves and do not have demonstrated economic viability. 4. Mineral Resource are reported above an economic cut-off calculated for each deposit. 5. All figures are rounded to reflect the relative accuracy of the estimates. 6. Note the Mineral Resource tabulation reports the % Li and not % Li2O. Contained Lithium is reported as Lithium Carbonate Equivalent (LCE) ES8: Mining Conventional truck and shovel operation has been selected as the most suitable open-pit mining method for Syväjärvi, Outovesi, Länttä and Rapasaari. For Länttä and Rapasaari underground operations is considered for the future. For Emmes, underground mining is the only possible mining method due to the underwater location of the ore body. The underground mining is excluded from the Mineral Reserves at this stage. A truck and shovel operation refers to the use of large, generally rigid body, off-highway haul trucks being loaded with blasted rock by large shovels or excavators. This combination of mining equipment is a proven technology and is used in many open pit mines throughout the world. The key points of a truck and shovel operation are: • The truck and shovel combination is a known and proven mining method, capable of handling most rock types in Finland. Potential mining contractors have suitable equipment readily available; • The haulage and loading equipment can handle both free-dig and blasted material; • The blending of ore from multiple deposits if needed is simple compared to other mining methods; and • The ability to produce the total annual mining rates is anticipated. In-pit ramps and waste rock haul roads are designed for off-highway trucks with a payload of 90 t. For waste mining, the bench height can vary between 10 – 20 m. Waste rock maximum particle size is not limited. ES7: Metallurgy and mineral processing There are three main process stages for producing lithium hydroxide from the Keliber ores: • Concentration (producing a spodumene concentrate from the ore); • Conversion (converting the spodumene from the unreactive α phase to the reactive β phase); and
SRK Consulting – 592138 SSW Keliber TRS Page xii SRK SSW_Keliber Project TRS_Final 13 December 2023 Report Date: 13 December 2023 Effective Date:31 December 2022 • Hydrometallurgical processing (leaching, purification and crystallisation stages to extract the Li from the β spodumene and precipitate it as high purity lithium hydroxide. Ore sorting Initial ore sorting tests focussed on optical and laser sorting. Following further comparative testing, X-Ray Transmission (XRT) ore sorting was selected for the Keliber project. Based on pilot-scale XRT ore sorting test results conducted on Syväjärvi ore samples, it was concluded that ore sorting is 73% efficient. There is a risk that ore sorting efficiency will vary across the Syväjärvi deposit. It is accordingly recommended that ore sorting variability tests be conducted across the Syväjärvi deposit. It was further assumed that the same efficiency would apply to other ore sources and ore types. There is a risk that other deposits will not perform with the same efficiency. It is accordingly recommended that these deposits be subjected to pilot ore sorting and variability tests using XRT ore sorting technology. The feed to the ore sorting test equipment comprised an artificial blend of Syväjärvi ore and waste rock. There is a risk that performance on mined ore may be less efficient that on the artificial composite ore feed. It is accordingly recommended that samples of mined ore from all deposits be subjected to pilot ore sorting tests using XRT ore sorting technology. Flotation Flotation has been tested at bench scale on most deposits and at pilot scale on samples of Länttä, Syväjärvi and Rapasaari ore. Flotation parameters are reasonably well understood but it is recommended that pilot-scale tests be undertaken on the other main sources of ore. Ore variability flotation tests were undertaken on Rapasaari samples selected from four different mineralised material types. These showed significant variability. It is recommended that similar variability programs be undertaken on all other deposits to ensure adequate understanding of spatial variability in flotation performance. Ultimately this should extend into the development of geo-metallurgical models for all deposits. Conversion Conversion test work was carried out by FLSmidth at their facility in the USA. The concentrate was calcined using a 2-stage cyclone preheater rotary kiln system, with 2 hours residence time and the burning zone solids temperature was generally maintained between 1 050-1 100 °C. These conditions resulted in an overall average alpha-to-beta conversion level of approximately 97% as measured by the conventional sulfuric acid solubility method. Some variation in optimum operating conditions were observed for concentrates from the different orebodies. Hydrometallurgy Outotec and Keliber have been working on the hydrometallurgical process since 2002. In June 2018 Keliber completed a DFS for a project to produce battery-grade lithium carbonate from spodumene- rich pegmatite. However, following further market studies it was decided to consider the production of battery- grade lithium hydroxide monohydrate (LiOH·H2O). A series of tests was completed to determine the production parameters of lithium hydroxide from spodumene ore, including the proprietary Metso-Outotec lithium hydroxide process at pilot scale. The key process stages for lithium hydroxide production are an initial alkaline leaching stage, using sodium carbonate and undertaken at high temperature and pressure, reacting the Li in the spodumene to solid phase lithium carbonate, followed by reacting this material with lime to produce lithium hydroxide in solution. The hydroxide is then crystallised out of solution following purification to form the final product. A continuous hydrometallurgical pilot plant trial was conducted at Metso-Outotec’s Pori Research Centre from 7 to 24 January 2020 on converted Syväjärvi concentrate. The pilot plant data indicated that the Li recovery reached the design figure of 86% for a brief period, with the plant achieving a lithium recovery in the region of the mid 80s for almost 20% of the run. More recently, Rapasaari spodumene concentrate produced in the GTK Mintec pilot plant was calcined in a continuous rotary kiln by FLSmidth in North America, after which it was shipped to Pori, Finland for hydrometallurgical test work. The average lithium concentration of the calcines corresponded to a 5.5% Li2O concentration. SRK Consulting – 592138 SSW Keliber TRS Page xiii SRK SSW_Keliber Project TRS_Final 13 December 2023 Report Date: 13 December 2023 Effective Date:31 December 2022 The continuous LiOH.H2O pilot was operated for approximately 17 days. The main process stages in the process were soda leaching, cold conversion, secondary conversion, ion exchange, LiOH.H2O crystallization and mother liquor carbonation. It was reported that in terms of impurity concentrations, almost all impurities were below detection limits. Notwithstanding, it is considered that the assessment of the product quality should be made in the context of developing relationships with potential off takers. It was reported that there is sufficient evidence in the pilot plant results to give confidence that the design recovery figure can be achieved in practice, following a suitable ramp-up period. The Keliber project is likely to be the first implementation of this specific lithium hydroxide flowsheet. While the individual unit processes are not novel, and while the Syväjärvi (2020) and Rapasaari (2022) pilot trials have significantly de-risked the flowsheet, a residual risk remains, as it does with the first example of any novel technology. In mitigation of such risk, the Lithium Hydroxide Refinery will commence hot commissioning on third party concentrate approximately nine months before concentrate is received from the Päiväneva concentrator. In addition, a ramp-up period of twenty four months has been allowed to achieve design throughput of Keliber concentrate. Metso Outotec will also provide a process guarantee will also be provided for the plant, although such a guarantee does not ultimately guarantee a process that will work so much as it defines the extent of financial compensation that will apply should it not. Importantly, it should be noted that the Mineral Reserves for Keliber have been declared on the basis that a ready market exists for the concentrate, without the need for a refinery. Mineral processing In February 2022, Keliber issued a DFS and has undertaken engineering studies to produce 15 000 tpa of battery- grade lithium hydroxide. The lithium hydroxide production process is split between two locations. Mined ore will be beneficiated at the Päiväneva concentrator located near the Rapasaari mine. Flotation concentrate will be transported to the Keliber Lithium Hydroxide Refinery where lithium hydroxide monohydrate will be produced as final product. The selected overall flowsheet comprises a conventional spodumene concentrator which includes crushing, ore sorting, grinding and spodumene recovery by flotation. Flotation concentrate is calcined to convert alpha- spodumene to beta-spodumene. The converted spodumene concentrate will be processed via the patented Metso-Outotec soda pressure leach to produce lithium hydroxide monohydrate. Modelled recovery parameters for each deposit are included in the Technical Economic Model. ES9: Mineral Reserve Estimates Sibanye-Stillwater announced on 28 November 2022, subsequent to securing an effective controlling interest of 84.96% in Keliber as announced on 3 October 2022, the approval of capital expenditure of EUR588m for the Keliber Lithium Project, beginning with the construction of the Keliber Lithium Hydroxide Refinery at Kokkola. Based on the Project FS completed during February 2022 and updated in October 2022 confirmed the robust economics of the Keliber Lithium Project at hydroxide prices significantly lower than the average prevailing spot prices over the previous 12 months. The open pit Mineral Reserves for the Keliber operations are summarised in Table ES- 5 with reference point for the material at the mill feed. In the reserve conversion, the dilution and mined ore tonnes are calculated as follows: Mined Ore = In-situ Tonnes x Mining Recovery x (100 + Unplanned External Dilution%) Black rock dilution, which can be reduced by using a sorter, is calculated with the following methodology: 𝐵𝑙𝑎𝑐𝑘 𝑅𝑜𝑐𝑘 𝐷𝑖𝑙𝑢𝑡𝑖𝑜𝑛 = 𝑇𝑜𝑡𝑎𝑙 𝐴𝑚𝑜𝑢𝑛𝑡 𝑜𝑓 𝐵𝑙𝑎𝑐𝑘 𝑅𝑜𝑐𝑘 𝑀𝑖𝑛𝑒 𝑂𝑟𝑒 The Mineral Reserves are based on the attributable interest of Sibanye-Stillwater in Keliber at 84.96%. . SRK Consulting – 592138 SSW Keliber TRS Page xiv SRK SSW_Keliber Project TRS_Final 13 December 2023 Report Date: 13 December 2023 Effective Date:31 December 2022 Table ES- 5: Mineral Reserve Statement for Keliber Oy operations as at 31 December 2022 Classification Deposit Mass (Mt) Li grade (%) LCE content (kt) Proven Syväjärvi 1.3 0.5 37.2 Rapasaari 1.8 0.5 44.1 Länttä 0.2 0.5 4.2 Total Proven 3.3 0.5 85.4 Probable Syväjärvi 0.5 0.4 10.3 Rapasaari 4.1 0.4 89.0 Länttä 0.1 0.5 2.1 Outovesi 0.2 0.6 6.7 Total Probable 4.9 0.4 108.2 Total Mineral Reserve 8.2 0.4 193.6 Notes: 1. Cut-off for open pit reserves 0.40% Li2O 2. Price EUR23 667/t LiOH.H2O 3. The reference point for Mineral Reserves are material delivered to the mill. 4. Measured material converted to Proven 5. Indicated Material Converted to Probable 6. No Inferred material included in the Mineral Reserve 7. The Rapasaari Mining permit has been granted but is under appeal ES10: Conversions In line with industry practice, Li Mineral Resources and Mineral Reserves total metal content is quoted in Lithium Carbonate (Li2CO3) Equivalent (LCE), which is one of the final products produced in the Li mining value chain. LCE is derived from in-situ Li content by multiplying by a factor of 5.323. Li Hydroxide Monohydrate (LiOH.H2O) can be derived from LCE by dividing by a factor of 0.88. Li has been derived from Lithium Oxide (Li2O) by multiplying by a factor of 0.465. ES11: Infrastructure Preparations are underway to construct the infrastructure, which will consist of a concentrator, a lithium hydroxide refinery and four open pit mines, together with access roads, power transmission lines, main electrical substations, electrical distribution, security, weighbridges, offices, laboratories, workshops, crushing units and internal roads. ES12: Environmental permitting requirements Keliber has obtained mining rights for Syväjärvi including the Syväjärvi Auxiliary Area, Länttä with an expiry date of 20/03/2027 and also for Rapasaari, which is granted, but not yet legally valid due to the appeal process that can continue between 18 to 30 months. Keliber has obtained prospecting rights for nine exploration areas, that are legally valid for a range of dates from 2023 to 2025. These include Emmes 2, Outovesi, Rapasaari and Syväjärvi 3-4. The prospecting right for Emmes 1 is owned by Keliber and is granted, but under appeal. Several other prospecting rights owned by Keliber is also granted but under appeal; these are listed in Chapter 2 of this report. The status of the environmental permitting is shown in Table ES- 6. SRK Consulting – 592138 SSW Keliber TRS Page xv SRK SSW_Keliber Project TRS_Final 13 December 2023 Report Date: 13 December 2023 Effective Date:31 December 2022 Table ES- 6: Status of the environmental permitting Site Permit Status Date Granted Syväjärvi mine Environmental Impact Assessment Finalised 29.3.2021 Environmental and water permit Valid 20.2.2019 Exception permit to moor frogs Valid 1.2.2020 Exception permit for diving beetles Valid 21.7.2020 Mining permit 1 Valid 13.12.2018 The right of use of the mining area Valid 9.8.2021 Mining Safety Permit Valid 13.10.2021 Rapasaari mine Environmental Impact Assessment Finalised 29.3.2021 Environmental permit Valid 28.12.2022 Mining Permit Granted, but not yet legally valid 23.03.2022 Mining Safety Permit Not started Länttä mine Environmental Impact Assessment Finalised 28.6.2018 Environmental permit Valid 7.11.2006 Mining Permit Valid 16.8.2016 Mining Safety Permit Not started Outovesi mine Environmental Impact Assessment Finalised 29.3.2021 Environmental permit Not started Mining Permit Not started Mining Safety Permit Not started Päiväneva concentrator Environmental Impact Assessment Finalised 29.3.2021 Environmental and water permit Application submitted 30.6.2021 Mining Permit (included in Rapasaari mining area) Application submitted 14.4.2021 Land use plan, local detailed plan In progress Building permit Not started Chemical permit Not started Keliber Lithium Hydroxide Refinery Environmental Impact Assessment Finalised 30.6.2021 Environmental permit Application submitted 4.12.2020 Building permit Not started Chemical Permit Not started ES13: Capital costs SRK reviewed the DFS and classified it as a pre-feasibility study (PFS) in terms of Table 1 to Paragraph (d) in S- K1300 [§229.1302(d)]. This implies Capital Cost Estimate (Capex) and Operating Cost Estimate (Opex) accuracy of ±25% and overall project contingency of ≤15% could be achieved. It should be noted, however, that estimation of capital and operating costs is inherently a forward-looking exercise. These estimates rely upon a range of assumptions and forecasts that are subject to change depending upon macro-economic conditions, operating strategy and new data collected through future operations. Therefore, changes in forward-looking assumptions can result in capital and operating costs that deviate more than 25% from the costs forecast herein. Keliber presents capital expenditure (capex) as Pre-development and Initial capex and Sustaining capex in the Keliber Lithium Project Draft Definitive Feasibility Study (DFS) Report (WSP, 2022). The capital includes the establishment of the open pits, the capital for the Päiväneva Concentrator and the Keliber Lithium Hydroxide Refinery. The underground mines described in the DFS are not included in the Mineral Reserve and therefore no Capital for the underground mines is declared. All data provided in this chapter is sourced from WSP, 2022 and the updated 18 December 2022 TEM (reference Keliber, 2022). Table ES- 7 is a high-level summary of the capex for the project.
SRK Consulting – 592138 SSW Keliber TRS Page xvi SRK SSW_Keliber Project TRS_Final 13 December 2023 Report Date: 13 December 2023 Effective Date:31 December 2022 Table ES- 7: Keliber capital summary Item Units Total Syväjärvi Mine EURm 8.1 Concentrator Plant (Päiväneva Site) EURm 156.6 Lithium Hydroxide Plant, Kokkola Site EURm 276.3 Engineering & Construction Services EURm 48.1 Site Facilities During Construction EURm 5.9 Construction Equipment EURm 7.2 Other Construction Services and Costs EURm 0.7 Owners' Cost EURm 23.5 Contingency EURm 56.0 Total Initial Capex (EURm) 582.5 (Source: Keliber, 2022) Sustaining capital includes provision for overburden removal for Syväjärvi Mine, development of Rapasaari, Länttä, and Outovesi mines, closure costs for the mines and concentrator plant, and individual item costs for the concentrator and the LiOH Plant. Sustaining capital amounts to EURm110.8. The Keliber Project has been re-classified as a study at a PFS level as discussed in Section ES5 and Section 1.1. SRK considers that the accuracy of the Capex is ±25% with a contingency of <15% in keeping with Table 1 to Paragraph (d) in S-K1300 [§229.1302(d)]. ES14: Operating costs Keliber has prepared the operating cost estimates in collaboration with Afry, Sweco, FLSmidth and Metso- Outotec. The operating cost estimate is divided into seven different areas: • Mining; • Päiväneva Concentrator; • Keliber Lithium Hydroxide Refinery; • Other variable costs; • Freight and Transportation; • Fixed costs; and • Royalties and Fees. The mining costs for open pit mining has been based on the contractors quotes the resultant averages over the LoM are listed per operation in Table ES- 8. The contractor costs have been increased from the 2019 FS by 25% to include cost escalation since then. Table ES- 8: Mining costs per open pit mining operation Site Total (Mt) Ore production (Mt) Stripping ratio Li2O (%) Average waste mining cost EUR/t Average ore mining cost EUR/t Syväjärvi OP 12.45 2.08 5.00 1.068 2.67 4.38 Rapasaari OP 63.49 6.88 8.23 0.901 2.89 3.73 Länttä OP 2.09 0.29 6.33 0.886 5.30 9.51 Outovesi OP 2.56 0.24 9.67 1.331 2.71 5.21 Concentration and lithium hydroxide production costs Lithium hydroxide production of 316 287 tonnes is planned over the life of the project. This includes 96 000 tonnes from external concentrates purchased over 6 years (Jan-42 to Dec-47) after depletion of the mine Mineral Reserves. Production from Keliber’s own spodumene concentrate is estimated at 220 287 tonnes LiOH.2H2O. SRK Consulting – 592138 SSW Keliber TRS Page xvii SRK SSW_Keliber Project TRS_Final 13 December 2023 Report Date: 13 December 2023 Effective Date:31 December 2022 Non-mining costs for production of lithium hydroxide from Keliber’s own concentrate are summarised in Table ES- 9. These include 10% contingency applied to most elements. Päiväneva Concentrator (crushing, sorting and concentration) Ore from the mine will be hauled to the primary crusher located at the Päiväneva concentrator. Primary crushing and sorting costs are then applied to the concentrator area. The operating cost of the concentrator plant includes energy, reagents, consumables, and maintenance. The same items are covered for the water treatment plant which is considered as being part of the concentrator site area. Energy is calculated based on the electrical load list of the equipment and the estimated power consumption. Reagents are derived from the process reagent consumption and costs are estimated from quotations provided by reagent suppliers. Consumables and maintenance costs were estimated based on recommendations derived from concentrator basic engineering work completed by Metso Outotec. Concentrator operating cost for the life of the project is estimated at EUR168.9m produced from Keliber concentrates. Keliber Lithium Hydroxide Refinery (conversion and LHP production) Operating costs of the Keliber Lithium Hydroxide Refinery are estimated at EUR544.7m or EUR2 473/t of LiOH.H2O produced from Keliber concentrates. The main contributors to the costs are energy, steam generation and reagents. Fixed costs Fixed costs include labour costs, LNG connection fees, LHP connection fees, various water retainer fees, fixed operating costs for heating of buildings, laboratory running costs, property related costs, utility system and G&A costs. These fixed costs are estimated at EUR336.4m over the life of the mines, with labour and G&A costs comprising 48% and 42% respectively. SRK considers that the Opex for the Keliber Project (mine and concentrator) has an accuracy of ±25%. Contingencies applied do not exceed 10% which satisfies the requirement of Table 1 to Paragraph (d) in S-K1300 [§229.1302(d)]. SRK Consulting – 592138 SSW Keliber TRS Page xviii SRK SSW_Keliber Project TRS_Final 13 December 2023 Report Date: 13 December 2023 Effective Date:31 December 2022 Table ES- 9: Non-mining cost summary Section Cost element LoM cost (EURk) LoM unit cost (EUR/t LiOH.H2O) Crushing & Sorting Crushing, Sorting & Stockpiling 6 607 29.99 Concentrator Energy 31 891 144.77 Reagents 66 167 300.36 Consumables 31 847 144.57 Maintenance 17 304 78.55 Concentrator Water Treatment Energy 3 496 15.87 Reagents 8 541 38.77 Consumables 1 759 7.98 Maintenance 1 329 6.03 Concentrate Loading & Transport 22 307 101.26 Concentrate Purchase - - Conversion Energy/Fuel 70 772 321.27 Other Consumables / Utilities 9 229 41.89 Lithium Hydroxide Plant Energy 68 527 311.08 Steam 86 832 394.18 Reagents 220 959 1 003.05 Process Water 2 186 9.92 Consumables 4 527 20.55 Utilities 12 328 55.96 Maintenance 16 536 75.07 LHP Water Treatment Reagents 17 238 78.25 Consumables 8 308 37.72 Energy 1 575 7.15 Other Costs 3 395 15.41 Other Variable Costs Service & Handling 1 823 8.28 Other Costs 550 2.50 Transport & Packing Side Rock Transport - - Final Product Transport 14 726 66.85 Processing Labour Labour Costs 161 365 732.52 Other Operating Costs District Heat 20 749 94.19 Subtotal Processing Cost 1 322 619 6 004.06 SG&A General & Administration 139 881 634.99 Property-related Costs 8 874 40.28 Others 5 589 25.37 Royalties & Fees Royalties 5 945 26.99 Fees 11 010 49.98 TOTAL 1 493 917 6 781.67 SRK Consulting – 592138 SSW Keliber TRS Page xix SRK SSW_Keliber Project TRS_Final 13 December 2023 Report Date: 13 December 2023 Effective Date:31 December 2022 ES15: Key risks The key risks identified for Keliber include uncertainty regarding permitting (especially the duration of the appeal processes), environmental and water-related concerns and issues related to the estimation of the Mineral Resources which directly impacts the Mineral Reserves. Paucity of geotechnical data, including rock mass strength and characterisation data, as well as confidence in structural geology models, result in conservative design and risk assumption and potential for the associated unknown ground conditions. ES16: Economic analyses SRK has placed reliance on Sibanye-Stillwater for the price assumptions and the marketing aspects of the lithium spodumene concentrate and lithium hydroxide products. The Net Present Value (NPV) of the post-tax cash flows for Keliber Mine and Concentrator is shown for a range of discount rates in Table ES-10. The NPV is determined in the model in euros and converted to ZAR and USD at the prevailing spot rate from 30 December 2022, the closest date to the Effective Date for which data is available. Table ES-10: Sensitivity to Discount Rate Discount Rate NPV (EURm) (USDm) (ZARm) 6.0% 223 239 4 058 8.0% 176 188 3 198 10.0% 136.4 145.8 2 478 12.0% 103 110 1 872 14.0% 75 80 1 358 The default price assumptions used are from the UBS December 2022 price deck. The average of the surveyed analysts is used in the Economic Analysis. A two-factor sensitivity, showing the sensitivity of the NPV (in EURm) to the USD/t price for spodumene concentrate and the working costs is included in Table ES-11. Table ES-11: Sensitivity of NPV to Changes in Price and Working Costs NPV in EURm Long-term Concentrate Price (USD/t) 834 886 938 990 1 042 1 094 1 146 1 198 1 250 84.7 -20% -15% -10% -5% 0% 5% 10% 15% 20% Working Costs (EUR/t) 61.7 -10% 39 69 100 130 160 190 221 251 281 65.1 -5% 27 58 88 118 148 179 209 239 269 68.5 0% 15 46 76 106 136.4 167 197 227 257 71.9 5% 3 34 64 94 124.5 155 185 215 245 75.4 10% -8 22 52 82 113 142.8 173 203 234 The average working costs are EUR68.5/t and the forecast long-term spodumene price is USD1042/t. The spot price and the forecast prices are currently very volatile. The operating margin of the mine and concentrator is currently estimated at 42% for the scheduled life of mine (LoM). The company has funded the capital for the project and limited liquidity risk is present. The operating margin is generally healthy and although the NPV changes substantially in response to price changes the operating margin is forecast to remain positive under most foreseeable scenarios. The post-tax NPV of the Mine and Concentrator producing spodumene concentrate for sale to a third-party is estimated at EUR136.4mat a 10% real discount rate with an IRR of 21.5%. This is on a 100% attributable basis. Sibanye-Stillwater owns 84.96%. The integration of the Refinery significantly improves the economics. However, the Refinery is not considered a Mineral Asset. A more detailed explanation is included in the Economic Analysis chapter along with the cash flows
SRK Consulting – 592138 SSW Keliber TRS Page xx SRK SSW_Keliber Project TRS_Final 13 December 2023 Report Date: 13 December 2023 Effective Date:31 December 2022 of the integrated business. The company intends to operate the business as an integrated business for the period where both the mine and the Refinery are operating. However, the Refinery will operate independently before and after the mine life and has the potential to expand to process third-party concentrates or produce alternate products during the mine life. ES17: Conclusions and recommendations The various aspects of the Keliber Lithium Project study meet the requirements for a prefeasibility study stage property in terms of Table 1 to Paragraph (d) in S-K1300 [§229.1302(d)] and the declaration of Mineral Resources and Mineral Reserves. SRK has independently verified the Mineral Resource and Mineral Reserve estimates and confirmed their reasonableness and compliance with the requirements of S-K1300. In general, the risks identified pertain to the declaration of Mineral Reserves and to work that would de-risk the operational phase. SRK Consulting – 592138 SSW Keliber TRS Page xxi SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Table of Contents 1 INTRODUCTION......................................................................................................... 30 1.1 Registrant .................................................................................................................................................... 30 1.2 Terms of reference and purpose of TRS ....................................................................................................... 31 1.3 Sources of information.................................................................................................................................. 31 1.4 Details of personal inspection ....................................................................................................................... 32 1.4.1 Qualified Persons ............................................................................................................................ 32 1.4.2 Independence .................................................................................................................................. 32 1.4.3 Consent ........................................................................................................................................... 32 1.5 Previous TRS ............................................................................................................................................... 33 1.6 Effective Date ............................................................................................................................................... 33 2 PROPERTY DESCRIPTION ....................................................................................... 34 2.1 Location of property...................................................................................................................................... 34 2.2 Finnish regulatory environment ..................................................................................................................... 34 2.2.1 Constitution of the Republic of Finland (731/1999 amended 2018) ................................................... 34 2.2.2 The Mining Act (621/2011, as amended) .......................................................................................... 36 2.2.3 Permits required .............................................................................................................................. 36 2.2.4 Income tax ....................................................................................................................................... 37 2.2.5 Carbon tax ....................................................................................................................................... 37 2.2.6 Royalties, fees and guarantees ........................................................................................................ 37 2.2.7 Finnish environmental legislation ..................................................................................................... 38 2.3 Mineral Rights .............................................................................................................................................. 40 2.3.1 Mining Rights ................................................................................................................................... 40 2.3.2 Prospecting Rights ........................................................................................................................... 40 2.3.3 Surface rights .................................................................................................................................. 44 2.3.4 Legal proceedings ........................................................................................................................... 44 2.3.5 Potential risks to tenure.................................................................................................................... 44 2.4 Property encumbrances and permitting requirements ................................................................................... 44 2.4.1 Environmental, water and waste authorizations, licences and permits .............................................. 44 2.5 Summary of permitting status ....................................................................................................................... 46 2.6 Significant factors and risks affecting access, title ......................................................................................... 46 3 ACCESSIBILITY, CLIMATE, LOCAL RESOURCES, INFRASTRUCTURE AND PHYSIOGRAPHY ....................................................................................................... 47 3.1 Topography, elevation and vegetation .......................................................................................................... 47 3.2 Accessibility ................................................................................................................................................. 47 3.3 Climate ........................................................................................................................................................ 48 3.4 Local resources and infrastructure ................................................................................................................ 48 4 HISTORY .................................................................................................................... 50 4.1 Previous operations, operators ..................................................................................................................... 50 4.2 Exploration and development work ............................................................................................................... 50 5 GEOLOGICAL SETTING, MINERALISATION AND DEPOSIT .................................. 52 5.1 Regional, local and project geology .............................................................................................................. 52 5.1.1 Syväjärvi geology............................................................................................................................. 52 5.1.2 Rapasaari geology ........................................................................................................................... 55 5.1.3 Länttä geology ................................................................................................................................. 56 5.1.4 Emmes geology ............................................................................................................................... 57 5.1.5 Outovesi geology ............................................................................................................................. 58 5.1.8 Mineralogy and geo-metallurgy ........................................................................................................ 61 5.2 Deposit type ................................................................................................................................................. 61 6 EXPLORATION .......................................................................................................... 63 6.1 Non-drilling activities .................................................................................................................................... 63 SRK Consulting – 592138 SSW Keliber TRS Page xxii SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 6.1.1 Geological/boulder mapping ............................................................................................................. 63 6.1.2 Geochemical sampling ..................................................................................................................... 63 6.2 Drilling, logging and sampling ....................................................................................................................... 64 6.2.1 Syväjärvi drilling ............................................................................................................................... 65 6.2.2 Rapasaari drilling ............................................................................................................................. 66 6.2.3 Länttä drilling ................................................................................................................................... 67 6.2.4 Emmes drilling ................................................................................................................................. 68 6.2.5 Outovesi drilling ............................................................................................................................... 69 6.2.6 Sampling procedures ....................................................................................................................... 72 7 SAMPLE PREPARATION, ANALYSES AND SECURITY .......................................... 74 7.1 Sample preparation methods and quality control measures .......................................................................... 74 7.2 Sample preparation, assaying and laboratory procedures ............................................................................. 74 7.3 Quality assurance and quality control measures ........................................................................................... 74 7.3.1 Replicates/duplicates ....................................................................................................................... 74 7.3.2 Certified reference materials ............................................................................................................ 75 7.3.3 Blanks ............................................................................................................................................. 75 7.4 Adequacy of sample preparation, security and analytical procedures ............................................................ 77 7.5 Unconventional analytical procedures ........................................................................................................... 77 8 DATA VERIFICATION ................................................................................................ 78 8.1 Data verification procedures applied ............................................................................................................. 78 8.2 Limitations in data verification ....................................................................................................................... 78 8.3 Adequacy of data ......................................................................................................................................... 78 9 METALLURGICAL TESTING AND MINERAL PROCESSING ................................... 79 9.1 Metallurgical Testing .................................................................................................................................... 79 9.1.1 Historical metallurgical test work ...................................................................................................... 79 9.1.2 Recent mineral processing test work ................................................................................................ 79 9.1.3 Recent conversion test work ............................................................................................................ 97 9.1.4 Recent hydrometallurgical testing for production of lithium carbonate and lithium hydroxide.............. 98 9.1.5 Recovery dependencies in mineral processing of Syväjärvi, Rapasaari and Länttä ......................... 103 9.1.6 Adequacy of data ........................................................................................................................... 108 9.1.7 Comment ....................................................................................................................................... 110 10 MINERAL RESOURCE ESTIMATES ....................................................................... 111 10.1 Key assumptions, parameters and methods used to estimate Mineral Resources ....................................... 111 10.2 Mineral Resource estimates ....................................................................................................................... 120 10.2.1 Conversions .................................................................................................................................. 120 10.3 Mineral Resource classification criteria and uncertainties ............................................................................ 121 10.4 Reasonable Prospects of Economic Extraction ........................................................................................... 123 10.5 Reconciliation of Mineral Resources ........................................................................................................... 125 11 MINERAL RESERVE ESTIMATES .......................................................................... 126 11.1 Procedure for the estimation of Mineral Reserves ....................................................................................... 126 11.1.1 Open pit optimisation ..................................................................................................................... 126 11.1.2 Open pit optimisation parameters ................................................................................................... 126 11.1.3 Optimization results ....................................................................................................................... 129 11.2 Open pit design .......................................................................................................................................... 135 11.2.1 Open pit geotechnical design parameters....................................................................................... 135 11.2.2 Mine design criteria ........................................................................................................................ 135 11.2.3 Syväjärvi ........................................................................................................................................ 137 11.2.4 Rapasaari ...................................................................................................................................... 137 11.2.5 Länttä ............................................................................................................................................ 138 11.2.6 Outovesi ........................................................................................................................................ 138 11.2.7 Modifying Factors .......................................................................................................................... 141 11.2.8 Cut-off grade ................................................................................................................................. 141 SRK Consulting – 592138 SSW Keliber TRS Page xxiii SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 11.3 Mineral Reserve estimates ......................................................................................................................... 143 11.3.1 Conversions .................................................................................................................................. 144 11.3.2 Comments ..................................................................................................................................... 144 12 MINING METHOD – OPEN PIT MINING .................................................................. 145 12.1 Rock engineering ....................................................................................................................................... 145 12.1.1 Rock mass quality .......................................................................................................................... 145 12.1.2 Rock strength parameters .............................................................................................................. 146 12.1.3 In-situ stress measurements .......................................................................................................... 146 12.2 Hydrogeology hydrology ............................................................................................................................ 146 12.2.1 Groundwater inflows ...................................................................................................................... 147 12.2.2 Water quality ................................................................................................................................. 147 12.2.3 Water balance ............................................................................................................................... 148 12.3 Life-of-Mine production schedule ................................................................................................................ 148 12.3.1 Life-of-Mine scheduling .................................................................................................................. 149 12.3.2 Production parameters ................................................................................................................... 152 12.3.3 Drilling and blasting ....................................................................................................................... 155 12.3.4 Loading and hauling....................................................................................................................... 156 12.3.5 Grade control ................................................................................................................................. 162 12.3.6 Primary crusher feed and ROM pad storage................................................................................... 162 12.3.7 Waste rock storage facilities ........................................................................................................... 162 12.3.8 Mine dewatering and water management ....................................................................................... 163 12.3.9 Explosives, fuel supply and storages .............................................................................................. 164 12.3.10 Open pit fleet ................................................................................................................................. 164 12.3.11 Manpower...................................................................................................................................... 165 12.3.12 Mining costs .................................................................................................................................. 166 13 PROCESSING AND RECOVERY METHODS .......................................................... 167 13.1 Concentrator throughput and design specifications ..................................................................................... 167 13.2 Process description - concentrator .............................................................................................................. 167 13.2.1 Primary crushing and raw material storage ..................................................................................... 168 13.2.2 Ore sorting and secondary crushing ............................................................................................... 169 13.2.3 Tertiary crushing ............................................................................................................................ 169 13.2.4 Grinding and classification ............................................................................................................. 169 13.2.5 Magnetic separation....................................................................................................................... 170 13.2.6 Desliming and pre-flotation............................................................................................................. 170 13.2.7 Flotation feed thickening ................................................................................................................ 170 13.2.8 Spodumene flotation ...................................................................................................................... 170 13.2.9 Tailings thickening ......................................................................................................................... 170 13.2.10 Concentrate thickening .................................................................................................................. 171 13.2.11 Concentrate filtration and concentrate storage ............................................................................... 171 13.2.12 Particle size and on-stream slurry analysers................................................................................... 171 13.3 Process design criteria - concentrator ......................................................................................................... 171 13.4 Requirements for energy, water and consumables...................................................................................... 172 13.4.1 Power ............................................................................................................................................ 172 13.4.2 Raw water pumping and treatment ................................................................................................. 172 13.4.3 Process water treatment ................................................................................................................ 172 13.4.4 Pre-float water treatment ................................................................................................................ 172 13.4.5 Excess water treatment.................................................................................................................. 173 13.4.6 Potable water................................................................................................................................. 173 13.4.7 Fire water ...................................................................................................................................... 173 13.4.8 On-line water management tool development for the concentrator .................................................. 173 13.5 Concentrator reagents and consumables .................................................................................................... 173 13.6 Lithium hydroxide production plant throughput and design specifications .................................................... 173 13.6.1 Concentrate receipt ....................................................................................................................... 174
SRK Consulting – 592138 SSW Keliber TRS Page xxiv SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 13.6.2 Spodumene calcination (conversion) .............................................................................................. 174 13.6.3 Pressure leaching of beta-spodumene ........................................................................................... 174 13.6.4 Soda leach residue filtration ........................................................................................................... 175 13.6.5 LiOH conversion ............................................................................................................................ 175 13.6.6 Leach residue filtration and handling .............................................................................................. 175 13.6.7 Polishing filtration........................................................................................................................... 175 13.6.8 Ion exchange ................................................................................................................................. 175 13.6.9 Crystallisation of lithium hydroxide ................................................................................................. 175 13.6.10 Crystallisation bleed treatment ....................................................................................................... 176 13.6.11 Effluent treatment .......................................................................................................................... 176 13.7 Process design criteria – lithium hydroxide chemical plant .......................................................................... 176 13.8 Requirements for energy, water and consumables...................................................................................... 177 13.8.1 Power ............................................................................................................................................ 177 13.8.2 Lithium chemical plant - site services ............................................................................................. 177 13.9 Plant commissioning and ramp-up .............................................................................................................. 177 14 INFRASTRUCTURE ................................................................................................. 179 14.1 General infrastructure ................................................................................................................................. 179 14.2 Tailings storage facility and ancillary infrastructure ...................................................................................... 184 14.3 Electrical infrastructure ............................................................................................................................... 186 14.4 Control and communications infrastructure ................................................................................................. 187 15 MARKET STUDIES .................................................................................................. 188 15.1 Context 188 15.2 Uses of Spodumene Concentrate ............................................................................................................... 188 15.3 Lithium value chain..................................................................................................................................... 189 15.4 Supply and demand ................................................................................................................................... 190 15.4.1 Demand ......................................................................................................................................... 190 15.4.2 Supply ........................................................................................................................................... 193 15.5 Market balance .......................................................................................................................................... 195 15.6 Prices 196 16 ENVIRONMENTAL AND SOCIAL STUDIES ............................................................ 197 16.1 Environmental Impact Studies Results ........................................................................................................ 197 16.1.1 Groundwater Studies ..................................................................................................................... 197 16.1.2 Biodiversity .................................................................................................................................... 197 16.1.3 Air Quality ...................................................................................................................................... 199 16.1.4 Noise ............................................................................................................................................. 199 16.2 Water Management .................................................................................................................................... 199 16.2.1 Surface waters and groundwater .................................................................................................... 200 16.2.2 Effects on surface waters ............................................................................................................... 201 16.2.3 Potentially Sulphate Soils ............................................................................................................... 202 16.2.4 Acid producing waste rock ............................................................................................................. 202 16.2.5 Waste Disposal .............................................................................................................................. 202 16.2.6 Closure Aspects ............................................................................................................................ 203 16.2.7 Environmental Site Monitoring........................................................................................................ 204 16.2.8 Social and Community Aspects ...................................................................................................... 205 16.2.9 Recreational Use ........................................................................................................................... 205 16.2.10 Land Use, Economic Activity and Population .................................................................................. 205 16.3 Environmental and social risks ................................................................................................................... 206 16.4 Environmental, social and governance summary ........................................................................................ 206 17 CAPITAL AND OPERATING COSTS ....................................................................... 207 17.1 Capital cost ................................................................................................................................................ 207 17.2 Operating costs .......................................................................................................................................... 209 17.2.1 Mining cost .................................................................................................................................... 209 17.2.2 Concentration and lithium hydroxide production costs .................................................................... 211 SRK Consulting – 592138 SSW Keliber TRS Page xxv SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 17.2.3 Päiväneva Concentrator (crushing, sorting and concentration) ....................................................... 211 17.2.4 Keliber Lithium Hydroxide Refinery (conversion and LHP production) ............................................. 212 17.2.5 Other variable costs ....................................................................................................................... 212 17.2.6 Freight and transportation .............................................................................................................. 212 17.2.7 Fixed costs .................................................................................................................................... 212 17.2.8 Royalties and fees ......................................................................................................................... 212 18 ECONOMIC ANALYSIS ........................................................................................... 213 19 ADJACENT PROPERTIES ....................................................................................... 218 20 OTHER RELEVANT DATA AND INFORMATION .................................................... 219 20.1 Project Implementation ............................................................................................................................... 219 20.2 Exploration Programme and Budget ........................................................................................................... 220 20.3 Risk review ................................................................................................................................................ 220 20.3.1 Introduction .................................................................................................................................... 220 20.3.2 Overview of specific risk elements.................................................................................................. 220 20.3.3 Potential economic impact of COVID-19......................................................................................... 221 20.3.4 Opportunities ................................................................................................................................. 221 21 INTERPRETATION AND CONCLUSIONS ............................................................... 223 21.1 Geology, exploration, sampling and Mineral Resources .............................................................................. 223 21.2 Geotechnical testing ................................................................................................................................... 224 21.3 Metallurgical testing and mineral processing ............................................................................................... 224 21.3.1 Ore beneficiation............................................................................................................................ 224 21.3.2 Chemical processing...................................................................................................................... 224 21.4 Mining and Mineral Reserves ..................................................................................................................... 225 21.5 Adjacent properties .................................................................................................................................... 225 21.6 Risk review and opportunities ..................................................................................................................... 225 21.7 Economic Analysis ..................................................................................................................................... 226 22 RECOMMENDATIONS ............................................................................................. 227 22.1 Exploration ................................................................................................................................................. 227 22.2 Hydrogeological investigation ..................................................................................................................... 227 22.3 Geotechnical testing ................................................................................................................................... 227 22.4 Mineral Resources ..................................................................................................................................... 227 22.5 Metallurgical testing and mineral processing ............................................................................................... 227 22.5.1 Ore beneficiation............................................................................................................................ 227 22.5.2 Chemical processing...................................................................................................................... 227 22.6 Mineral Reserve ......................................................................................................................................... 228 23 REFERENCES/DATA SOURCES ............................................................................ 229 23.1 Documents provided by the Company ........................................................................................................ 229 23.2 Public domain documents........................................................................................................................... 230 24 RELIANCE ON INFORMATION PROVIDED BY REGISTRANT .............................. 231 25 DATE AND SIGNATURE PAGE ............................................................................... 232 SRK Consulting – 592138 SSW Keliber TRS Page xxvi SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 List of Tables Table 2-1: Co-ordinates of the Keliber Lithium Project elements ............................................................................. 34 Table 2-2: Key environmental legislation ................................................................................................................ 39 Table 2-3: Summary of valid or granted mining and exploration permits as at 31 December 2022 .......................... 41 Table 2-4: Summary of exploration permit applications as at 31 December 2022.................................................... 42 Table 2-5: Environmental permitting status as at 31 December 2022 ..................................................................... 45 Table 2-6: Summary of permitting status - 31 December 2022 ............................................................................... 46 Table 4-1: Previous operators ................................................................................................................................ 50 Table 4-2: Summary of the sampling and ground geophysics (after Ahtola et al 2015) ............................................ 51 Table 6-1: Drilling completed over the Keliber Lithium Project ................................................................................ 65 Table 7-1: Reported lithium content for the three in-house standards ..................................................................... 75 Table 9-1: Syväjärvi comminution characteristics ................................................................................................... 85 Table 9-2: Summary flotation results ...................................................................................................................... 86 Table 9-3: TOMRA ore sorting mass balance 2021 ................................................................................................ 97 Table 9-4: Modal composition of the waste rocks of Syväjärvi, Länttä and Rapasaari ........................................... 106 Table 9-5: Recovery parameters .......................................................................................................................... 108 Table 9-6: Modelled lithium recoveries included in the Technical Economic Model ............................................... 108 Table 10-1: Drill hole (and channel sample) data informing the Mineral Resource estimates .................................. 111 Table 10-2: Modelled semi-variogram parameters for Syväjärvi, Rapasaari and Tuoreetsaaret .............................. 116 Table 10-3: Search parameters for all Keliber deposits .......................................................................................... 117 Table 10-4: Summary of density measurements and mean values ......................................................................... 117 Table 10-5: Mineral Resource Statement (31 December 2022) for Keliber Oy operations ....................................... 120 Table 10-6: Lithium product conversion matrix ....................................................................................................... 120 Table 10-7: Cut-off calculation parameters ............................................................................................................. 124 Table 10-8: Keliber reconciliation between the 2022 and 2021 Mineral Resource Estimates ................................... 125 Table 11-1: Open pit optimisation input parameters ............................................................................................... 127 Table 11-2: Mining operational costs by mining levels, 2017-2019 (processing plant then to be located in Kaustinen) 128 Table 11-3: Summarized block model properties.................................................................................................... 129 Table 11-4: Syväjärvi analysis results .................................................................................................................... 130 Table 11-5: Länttä analysis results......................................................................................................................... 131 Table 11-6: Outovesi analysis results .................................................................................................................... 132 Table 11-7: The Rapasaari open pit optimisation results in the bench by bench schedule according to the open pit phases and Mineral Resource categories ............................................................................................ 133 Table 11-8: Recommended parameters for open pit designs .................................................................................. 137 Table 11-9: Mineral Reserves for Keliber open pit operations as at 31 December 2022 .......................................... 144 Table 12-1: Summary of groundwater inflows per deposit ...................................................................................... 147 Table 12-2: Keliber Lithium Project production summary ....................................................................................... 149 Table 12-3: Key design criteria for daily ore production .......................................................................................... 152 Table 12-4: Recommended parameters for open pit bench drill design ................................................................... 155 Table 12-5: Open pit mining equipment requirements according to contractor quotes ............................................. 164 Table 12-6: Mining equipment requirements for Rapasaari and Syväjärvi open pits, including a schedule by Contractor A ....................................................................................................................................... 165 Table 12-7: Mining cost per open pit mining operation ........................................................................................... 166 Table 13-1: Key process design criteria - concentrator ........................................................................................... 171 Table 13-2: Concentrator reagents and consumables ............................................................................................ 173 Table 13-3: Key process design criteria – lithium hydroxide chemical plant ............................................................ 176 Table 16-1: Field studies carried out at Syväjärvi, Rapasaari and Outovesi mine sites and Vionneva natura 2000 area. 198 Table 17-1: Keliber Lithium Project Capital Summary ............................................................................................. 207 Table 17-2: Pre-development and initial capex schedule ........................................................................................ 208 Table 17-3: Keliber Lithium Project sustaining capital schedule .............................................................................. 209 Table 17-4: Open pit mining optimisation parameter summary ............................................................................... 210 Table 17-5: Non-mining cost summary................................................................................................................... 211 SRK Consulting – 592138 SSW Keliber TRS Page xxvii SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Table 18-1: Mine and Concentrator Only with scheduled Mineral Reserve ................................................................... 215 Table 18-2: Sensitivity of NPV to Revenue and Working Costs .................................................................................... 216 Table 18-3: Sensitivity to Discount Rate ...................................................................................................................... 216 Table 18-4: Price and Exchange Rate forecasts .......................................................................................................... 216 Table 20-1: Project Milestones .............................................................................................................................. 219 Table 21-1: Sensitivity to Discount Rate ................................................................................................................. 226 Table 21-2: Sensitivity of NPV to Changes in Price and Working Costs .................................................................. 226
SRK Consulting – 592138 SSW Keliber TRS Page xxviii SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Table of Figures Figure 1.1: Simplified SSW corporate structure ....................................................................................................... 31 Figure 1.2: Sibanye Battery Metals (Pty) Ltd - corporate structure ........................................................................... 32 Figure 2.1: Locality plan of the Keliber Lithium Project’s elements ........................................................................... 35 Figure 2.2: Mining and exploration permits as at 31 December 2022 ....................................................................... 43 Figure 5.1: Regional geology of Keliber (modified after Ahtola et al., 2015) ............................................................. 54 Figure 5.2: Project Geology of the Keliber Lithium Project (modified after Ahtola et al., 2015) .................................. 54 Figure 5.3: Syväjärvi - 3D view of modelled pegmatites looking west, with photo showing exposed pegmatite in exploration tunnel ................................................................................................................................. 55 Figure 5.4: Rapasaari - 3D view of modelled pegmatites looking southwest ............................................................ 56 Figure 5.5: Länttä - 3D view of modelled pegmatites looking northeast .................................................................... 57 Figure 5.6: Emmes - 3D view of modelled pegmatites looking northwest ................................................................. 58 Figure 5.7: Outovesi - 3D view of modelled pegmatites looking northeast ................................................................ 59 Figure 5.8: Leviäkangas - vertical section view of modelled pegmatites looking east ............................................... 60 Figure 5.9: Tuoreetsaaret – 3D view of modelled pegmatites looking northwest ...................................................... 61 Figure 5.10: Schematic plan view of a granite source showing evolution through to LCT pegmatite ........................... 62 Figure 6.1: Map showing spodumene pegmatite boulders and deposits .................................................................. 63 Figure 6.2: Regional distribution of Li in till and the locations of known lithium deposits ........................................... 64 Figure 6.3: Syväjärvi – completed drilling with photo showing exploration tunnel ..................................................... 66 Figure 6.4: Rapasaari - completed drilling ............................................................................................................... 67 Figure 6.5: Länttä – completed drilling with photographs showing exposed pegmatite at surface ............................. 68 Figure 6.6: Emmes – completed drilling .................................................................................................................. 69 Figure 6.7: Outovesi – completed drilling ................................................................................................................ 70 Figure 6.8: Tuoreetsaaret – Completed Drilling ....................................................................................................... 71 Figure 6.9: Leviäkangas – completed drilling........................................................................................................... 72 Figure 7.1: Plots of core replicate and laboratory pulp duplicate checks for Li2O from 2018 to 2020 ......................... 75 Figure 7.2: CRM control charts from 2018 to 2020 in analytical order ...................................................................... 76 Figure 7.3: CRM control chart showing performance of AMIS0355 since 2016 ........................................................ 77 Figure 9.1: Spodumene pegmatite at the end of the tunnel and numbered ore piles before transport to GTK Mintek 82 Figure 9.2: Syväjärvi pilot sample location – plan and long section views ................................................................ 83 Figure 9.3: Lithium recovery as a function of feed grade ......................................................................................... 87 Figure 9.4: Lithium recovery as a function of concentrate grade .............................................................................. 88 Figure 9.5: Variability in Rapasaari flotation recovery .............................................................................................. 90 Figure 9.6: Variability in Outovesi flotation recovery ................................................................................................ 91 Figure 9.7: Syväjärvi pilot tests 2019 ...................................................................................................................... 93 Figure 9.8: 65-litre Autoclave used in the semi-continuous pilot processing ........................................................... 101 Figure 9.9: Simplified process flowsheet of LiOH*H2O production ......................................................................... 102 Figure 9.10: Lithium recovery at 4.5% Li2O in the concentrate vs lithium grade in the feed ...................................... 104 Figure 9.11: Grade recovery curves of the geo-metallurgical dilution study .............................................................. 105 Figure 9.12: Recovery at 4.5% Li2O against MgO% of the feed sample ................................................................... 106 Figure 9.13: Fitted lines for lithium recovery into the spodumene concentrate vs wall rock dilution in the feed sample 107 Figure 10.1: Syväjärvi geological interpretation example on Section 7 062 200N ..................................................... 112 Figure 10.2: Syväjärvi (looking east) and Rapasaari (looking northeast) orebody overview ...................................... 114 Figure 10.3: Rapasaari main pegmatite bodies selected for variography (showing search ellipses) ......................... 115 Figure 10.4: Tuoreetsaaret pegmatite bodies .......................................................................................................... 116 Figure 10.5: Plan view of the Syväjärvi Mineral Resource model with Li2O grades................................................... 118 Figure 10.6: Isometric view looking northeast of the Rapasaari Mineral Resource model with Li2O grades .............. 118 Figure 10.7: Rapasaari X and Y axis swath plots for all estimated domains ............................................................. 119 Figure 10.8: Plan view of the Syväjärvi resource model with Mineral Resource classification ................................... 122 Figure 10.9: Isometric view looking northeast of the Rapasaari resource model with Mineral Resource classification 122 Figure 10.10: LoM production ................................................................................................................................... 124 SRK Consulting – 592138 SSW Keliber TRS Page xxix SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Figure 11.1: Rapasaari pit-by-pit optimisation results .............................................................................................. 134 Figure 11.2: Rapasaari open pit geometry. (blue geometry presents the 10-year production; brown the 9-year production) ......................................................................................................................................... 134 Figure 11.3: Open pit slope sections and naming according to AFRY ...................................................................... 136 Figure 11.4: Syväjärvi open pit mine layout and Ore Reserves (blue= Proven Reserves, green = Probable Reserves) 139 Figure 11.5: Rapasaari open pit mine layout and Ore Reserves (blue= Proven Reserves, green = Probable Reserves) 139 Figure 11.6: Länttä open pit mine layout and Ore Reserves (blue= Proven Reserves, green = Probable Reserves) . 140 Figure 11.7: Outovesi open pit mine layout and Ore Reserves (blue= Proven Reserves, green = Probable Reserves) 140 Figure 11.8: Rapasaari - breakeven calculation results for Rapasaari. Profit/loss are for 7.015 Mt of ore. The breakeven value is reached at 0.27 % Li2O cut-off grade ..................................................................................... 142 Figure 11.9: Syväjärvi - breakeven calculation results for Syväjärvi. Profit/loss are for 7.015 Mt of ore. The breakeven value is reached at 0.27 % Li2O cut-off grade ..................................................................................... 142 Figure 11.10: Länttä - breakeven calculation results for Länttä. Profit/loss are for 7.015 Mt of ore. The breakeven value is reached at 0.27 % Li2O cut-off grade............................................................................................... 143 Figure 11.11: Outovesi - breakeven calculation results for Outovesi. Profit/loss are for 7.015 Mt of ore. The breakeven value is reached at 0.27 % Li2O cut-off grade ..................................................................................... 143 Figure 12.1: Annual LoM feed production schedule ................................................................................................. 150 Figure 12.2: Annual LoM feed production schedule ................................................................................................. 151 Figure 12.3: Sulphide-bearing side rock by deposit ................................................................................................. 151 Figure 12.4: Pre-production waste rock mining and first ore production blast ........................................................... 154 Figure 12.5: Conceptual open pit bench drill design ................................................................................................ 156 Figure 12.6: Blasting sequence for open pit bench drill design ................................................................................ 156 Figure 12.7: External pit ore and waste rock haulage road design with CAT 777G space requirements (peat layer ≤1 m) 158 Figure 12.8: External pit ore and waste rock haulage road design with CAT 777G space requirements (peat layer >1 m) 159 Figure 12.9: In-pit ramp configuration for 15 m ramp width ...................................................................................... 160 Figure 12.10: In-pit ramp configuration for 20 m ramp width ...................................................................................... 160 Figure 12.11: In-pit ramp configuration for 25 m ramp width ...................................................................................... 161 Figure 12.12: In-pit ramp configuration for 30 m ramp width ...................................................................................... 161 Figure 12.13: Principal cross-section of the waste rock storage facility at Rapasaari ................................................. 163 Figure 13.1: Päiväneva concentrator - simplified block flow diagram ....................................................................... 168 Figure 13.2: Basic ore sorting operating principle .................................................................................................... 169 Figure 13.3: Simplified block flow diagram of the lithium hydroxide production plant ................................................ 174 Figure 13.4: Plant ramp-up schedules .................................................................................................................... 178 Figure 14.1: General Layout of the Länttä Mine Site................................................................................................ 179 Figure 14.2: General Layout of the Rapasaari Mine Site ......................................................................................... 180 Figure 14.3: General layout of the Syväjärvi Mine site ............................................................................................. 181 Figure 14.4: General layout of the Outovesi Mine site ............................................................................................. 182 Figure 14.4: Overall layout of the Päiväneva Concentrator site................................................................................ 183 Figure 14.5: Overall Layout of the LiOH Plant at the Kokkola KIP Site ..................................................................... 184 Figure 18-1: Keliber Mine and Concentrator Feed by Source ....................................................................................... 213 SRK Consulting – 592138 SSW Keliber TRS Page 30 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date:13 December 2023 Effective Date: 31 December 2022 1 INTRODUCTION [§229.601(b)(96)(iii)(B)(2)] 1.1 Registrant [§229.601(b)(96)(iii)(B)(2)(i)] Sibanye Stillwater Limited (Sibanye-Stillwater, SSW, or also referred to as the Company), a limited public company with its registered office in South Africa, is involved in the exploration, development, mining and processing of lithium spodumene mineral deposits in Central Ostrobothnia, Finland. SSW (Figure 1.1) holds a share in the mineral rights to the Keliber Lithium Hydroxide Project (Keliber Lithium Project) through its wholly-owned subsidiary, Sibanye Battery Metals (Pty) Ltd (Figure 1.2), which owns 100% of Keliber Lithium (Pty) Ltd, which in turn owns 84.96% of Keliber Oy (Keliber). This Technical Report Summary (TRS) relates to the Keliber Lithium Project, which consists of exploration and planned mining operations around Kaustinen, a planned mineral processing plant at Kaustinen (the Keliber Lithium Concentrator) and a planned conversion plant at Kokkola, the Keliber Lithium Hydroxide Refinery. The Keliber Lithium Project plan is based on a definitive feasibility study (DFS) dated February 2022 (WSP, 2022). The DFS is based on updated Resource models and additional deposits. After the DFS was reviewed during 2022, a decision was made to report Mineral Reserves for the open pit operations with the understanding that SRK will classify the level of study for the project at Pre-Feasibility Study (PFS) level because SRK does not believe that the study satisfies all the requirements of the United States Securities and Exchange Commission’s (SEC’s) Subpart 1300 of Regulation S-K (S-K1300), under the Securities Act of 1933 and the Securities Exchange Act of 1934 for a feasibility study (FS). Keliber is a combination of two businesses – the mine and the refinery with the concentrator being considered as part of the mine. Both businesses are run as standalone entities. The Mineral Reserves and Mineral Resources can be declared based solely on the economics of the production of concentrate from the mine. The Kokkola lithium hydroxide refinery (Keliber Lithium Refinery) can, similarly, be run profitably when processing third-party concentrates. The Keliber Lithium Refinery is thus not considered a Mineral Asset and discussions in this document include the refinery only because there are synergies, and it is the intention to mostly process own concentrate. The declared Mineral Reserves will be for the open pit portion of the study only. Sibanye-Stillwater announced on 28 November 2022, subsequent to securing an effective controlling interest of 84.96% in Keliber, as announced on 3 October 2022, the approval of capital expenditure of EUR 588m for the Keliber Lithium Project, beginning with the construction of the Keliber Lithium Hydroxide Refinery. It should be noted that estimation of capital and operating costs is inherently a forward-looking exercise. These estimates rely upon a range of assumptions and forecasts that are subject to change depending upon macro- economic conditions, operating strategy and new data collected through future operations. Therefore, changes in forward-looking assumptions can result in capital and operating costs that deviate more than 25% from the costs forecast herein. The Keliber Lithium Project is classified as a pre-feasibility study (PFS in terms of Table 1 to Paragraph (d) in S-K1300 [§229.1302(d)]. A final DFS was made available to SRK during 2022. SRK reviewed the DFS and classified it as a PFS for the open pit mining operations and a Scoping Study for the underground operations. This implies Capital Cost Estimate (Capex) and Operating Cost Estimate (Opex) accuracy of ±25% and overall project contingency of ≤15% should be achieved. SRK Consulting – 592138 SSW Keliber TRS Page 31 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date:13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Simplified SSW corporate structure Project No. 592138 Figure 1.1: Simplified SSW corporate structure 1.2 Terms of reference and purpose of TRS [§229.601(b)(96)(iii)(B)(2)(ii)] Terms of reference SSW commissioned SRK Consulting (South Africa) (Pty) Ltd (SRK) to compile this TRS for Keliber according to Item 601 of the United States Securities and Exchange Commission’s (SEC’s) Subpart 1300 of Regulation S-K (S-K1300), under the Securities Act of 1933 and the Securities Exchange Act of 1934. Purpose This report is the first TRS for the Keliber Lithium Project and supports the disclosure of Mineral Resources and Mineral Reserves at 31 December 2022. The Mineral Resources and Mineral Reserves have been prepared and reported according to the requirements of the SAMREC Code (2016 Edition), which uses terms and definitions that are consistent with the requirements of S-K1300. Compliance This TRS report has been compiled to ensure regulatory compliance. Notation This report uses a shorthand notation to demonstrate compliance with Item 601 of Regulation S-K1300 as follows: • [[§229.601(b)(96)(iii)(B)(2)] represents sub-section (iii)(B)(2) of section 96 of CFR 229.601(b) (“Item 601 of Regulation S-K”). 1.3 Sources of information [§229.601(b)(96)(iii)(B)(2)(iii)] Sources of information and data used in the preparation of the TRS are included in Section 24. SSW has confirmed in writing that to its knowledge, the information provided by it to SRK was complete and not incorrect, misleading or irrelevant in any material aspect. SRK has no reason to believe that any material facts have been withheld.
SRK Consulting – 592138 SSW Keliber TRS Page 32 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date:13 December 2023 Effective Date: 31 December 2022 1.4 Details of personal inspection [§229.601(b)(96)(iii)(B)(2)(iv)] The various key sites were visited by SRK from 14 – 16 March 2022 and 23 – 27 January 2023, including the locations of key mining areas, the core shed and the proposed locations of both the Keliber Lithium Concentrator and the Keliber Lithium Hydroxide Refinery. 1.4.1 Qualified Persons [§229.1302(b)(1)(ii)] This report was prepared by SRK, a third-party consulting firm comprising mining experts in accordance with §2291302(b)(1). SSW has determined that SRK meets the qualifications specified under the definition of Qualified Person in §229.1300. References to the Qualified Person, or QP, in this report are references to SRK Consulting (South Africa) (Pty) Ltd and not to any individual employed by SRK. 1.4.2 Independence Neither SRK nor any of its employees or associates employed in compiling this TRS for Keliber, nor any directors of SRK, have at the date of this report, nor have had within the previous two years, any shareholding in the Company, SSW’s subsidiary companies, the Keliber Lithium Project, any of the Company’s Advisors, or any other pecuniary, economic or beneficial interest, or the right to subscribe for such interest, whether direct or indirect, in the Company, SSW’s subsidiary companies, the Keliber Lithium Project, any of the Company’s Advisors or the outcome of the work. Consequently, SRK considers itself to be independent of the Company, its directors, senior management and Advisors. SSW Keliber Lithium Project Sibanye Battery Metals (Pty) Ltd - corporate structure Project No. 592138 Figure 1.2: Sibanye Battery Metals (Pty) Ltd - corporate structure 1.4.3 Consent SRK has given, and has not withdrawn, its written consent for the use of this TRS report for regulatory compliance purposes. SRK Consulting – 592138 SSW Keliber TRS Page 33 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date:13 December 2023 Effective Date: 31 December 2022 1.5 Previous TRS [§229.601(b)(96)(iii)(B)(2)(v)] This TRS serves as an amendment to the Original 2022 Keliber TRS. The Original 2022 Keliber TRS was the first TRS for the Keliber Lithium Project filed by SSW in support of the reporting of Mineral Resources and Mineral Reserves for Keliber. Therefore, no update of a previous TRS is applicable. 1.6 Effective Date [§229.1302(b)(iii)(3)] The effective date of the TRS is 31 December 2022, which satisfies the S-K1300 requirement of a current report. SRK Consulting – 592138 SSW Keliber TRS Page 34 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date:13 December 2023 Effective Date: 31 December 2022 2 PROPERTY DESCRIPTION [§229.601(b)(96)(iii)(B)(3)] 2.1 Location of property [§229.601(b)(96)(iii)(B)(3)(i)] The Keliber Lithium Project is located in Central Ostrobothnia, Finland, approximately 385 km north-northwest of Helsinki, in the municipalities of Kaustinen, Kokkola and Kruunupyy. The Keliber Lithium Project consists of mining operations around Kaustinen, the Keliber Lithium Concentrator at Päiväneva near Kaustinen and the planned Keliber Lithium Hydroxide Refinery at Kokkola and ongoing exploration activities. There are nine elements to the project: • Seven spodumene exploration or mining properties at Syväjärvi, Rapasaari, Länttä, Outovesi, Emmes Leviäkangas and Tuoreetsaaret; • The Keliber Lithium Concentrator at Päiväneva; and • The Keliber Lithium Hydroxide Refinery planned at the Kokkola Industrial Park (KIP). The co-ordinates for Keliber in Finnish national grid coordinates (ETRS-TM35FIN) are shown in Table 2-1; the location of the different project elements is shown in Figure 2.1. Table 2-1: Co-ordinates of the Keliber Lithium Project elements Type Area Geographical Co-ordinates (ETRS-TM35FIN) Latitude (N) Longitude (E) Exploration/mine property Syväjärvi 7 063 218 341 875 Rapasaari 7 061 966 343 691 Länttä 7 057 934 358 386 Outovesi 7 063 902 338 547 Emmes 7 06 5038 330 803 Leviäkangas 7 06 0472 338 085 Tuoreetsaaret 7 061 929 342 665 Concentrator Päiväneva 7 060 429 343 076 Planned lithium hydroxide refinery KIP, Kokkola 7 086 600 306 020 2.2 Finnish regulatory environment [§229.601(b)(96)(iii)(B)(2)(iv)] A brief overview of the regulatory environment in Finland within which Keliber operates and that affects Keliber is summarized below. 2.2.1 Constitution of the Republic of Finland (731/1999 amended 2018) The ultimate source of national law in Finland is the Constitution, which defines the basis, structures and organisation of government and the relationship between the different constitutional organs; it defines the fundamental rights of Finnish citizens and other individuals. Section 20 of the Constitution covers responsibility for the environment; this states that everyone is responsible for nature, the environment and the national heritage and that ”public authorities shall endeavour to guarantee for everyone the right to a healthy environment and for everyone the possibility to influence the decisions that concern their own living environment”1. 1 https://www.refworld.org/pdfid/4e5cf5f12.pdf SRK Consulting – 592138 SSW Keliber TRS Page 35 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date:13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Locality plan of the Keliber Lithium Project’s elements (Source: WSP, 2022) Project No. 592138 Figure 2.1: Locality plan of the Keliber Lithium Project’s elements
SRK Consulting – 592138 SSW Keliber TRS Page 36 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 The Mining Act (621/2011 as amended) prescribes how mining activities are conducted in order to meet the objectives of Section 20. This must be read along with the following pertinent legislation: • Finnish Government Decree on mining safety (1571/2011) • Finnish Government Decree on mining activities (391/2012); and • Finnish Government Decree on mine hoists (1455/2011). 2.2.2 The Mining Act (621/2011, as amended) All minerals are owned by the State of Finland. The objective of the Mining Act 621/2011 (Mining Act) is “to promote mining and organise the use of areas required for it, and exploration, in a socially, economically, and ecologically sustainable manner.”2 The Mining Act defines exploration and mining activities; the applicable permitting that is required for each and the validity and obligations thereof; the definition of a mining area and its establishment; the safety and supervision required on a mine; and the termination of mining and returning the possession of the mine when mining has ceased. The Finnish Safety and Chemicals Agency (TUKES) is responsible for issuing the relevant permits required for exploration and mining activities. The permits are described below. 2.2.3 Permits required 2.2.3.1 Exploration permit This allows the holder to explore or prospect but not to exploit a deposit. The permit gives the holder the right to: • to conduct exploration; • to explore the structures and composition of geological formations; • to conduct other exploration in order to locate a deposit, investigate its quality, extent, and degree of exploitation; • to build, or transfer to the exploration area, temporary constructions and equipment necessary for exploration activity; and • to conduct other exploration in order to prepare for mining activity. An exploration permit is valid for a maximum period of three years and may be extended until a maximum of fifteen years’ validity has been reached. Extension is dependent on the exploration having been effective and systematic; that all Mining Act obligations and all permit regulations have been complied with; that extension will not cause an undue burden to public or private interests and that further research is required to confirm whether exploitation is possible. The permit holder has priority for being granted a mining permit. At all times, the property owner retains the right to use and govern the area. 2.2.3.2 Mining permit A mining permit is required to establish a mine. Once a permit is granted, the permit holder has the right to: • Perform exploration within the mining area; • To exploit: o The minerals found within the mining area; o Any organic or inorganic surface materials, excess rock, and tailings generated as a by-product of mining activities; and o Other materials belonging to the bedrock and soil of the mining area, where their use is required for the mining operations. 2 Ministry of Employment and the Economy, Finland. (2011) SRK Consulting – 592138 SSW Keliber TRS Page 37 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Permits are usually granted until further notice, but they may be granted for a fixed period of time; the validity of a fixed term mining permit may be extended if mining has not yet commenced or if operations have been interrupted for a period of five years. The holder may apply to change the size of the area of a mining permit and may also assign the permit to another party. The holder must ensure that mining activities do not damage people’s health; do not impact public safety; do not cause significant harm to or infringe on public or private interests; do not obviously waste mining minerals and do not cause prevent or hinder the potential future use and/or excavation work at the mine and the deposit. 2.2.3.3 Mining safety permit A mining safety permit is required to construct and operate a mine (Mining Act (621/2011) and Mining Safety content requirements under Regulation (EU) No 1571/2011). This covers the structural and technical safety of a mine, the prevention of hazards and accidents and the mitigation of adverse effects of an accident. A mining permit must first be legally binding before a mining safety permit can be issued. 2.2.3.4 Surface Ownership It is not a prerequisite that the entity conducting the exploration and/or mining own the land on which the activities are taking place. However, if the land is privately owned, agreement must be reached with the owner before activities can commence. Conditions to such agreements must be determined and agreed upon by both parties and usually include some form of compensation. 2.2.4 Income tax Income taxes are based on a company’s net income and are levied as prepayments during the fiscal year, which is generally the calendar year. If the company’s accounting year differs from the calendar year, taxes are based on the accounting period or the accounting period that ends during the calendar year. Advance payments may be collected in two or twelve instalments during the year: • Two instalments: if the total tax is ≤€2 000, payments are made in the third and ninth months; and • Twelve instalments: if the total tax is >€2 000, payments must be made each month, by the 23rd of the month. Corporate income tax is currently at 20%. 2.2.5 Carbon tax Finland introduced a carbon tax in 1990 based on the carbon content of fossil fuels. The average tax is currently €62.00 per tonne of CO2. 2.2.6 Royalties, fees and guarantees [§229.601(b)(96)(iii)(B)(3)(vii)] Royalties are payable on any ore mined, as the State owns the minerals. The base rate is €0.5 per tonne of ore mined, indexed to today’s value. The royalties are based on agreements between the Ministry of Employment and the Economy and Keliber and are tied to the Producer Price Index. A range of different fees are also payable; these include: • Landowner payments according to the Mining Act during the life of mine: €50/ha/year and per payable metal content (0.15% of the concentrate value); • Exploration tenements: payments to landowners based on exploration permits; • REACH payments (Registration, Evaluation, Authorisation and Restriction of Chemicals): upfront and annual payments; and • Property tax. Closure cost (rehabilitation) guarantees are required by the permit authorities, covering all mines and concentrators. SRK Consulting – 592138 SSW Keliber TRS Page 38 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 2.2.6.1 Royalties Royalties that must be considered are for the state of Finland for the mined ore from Syväjärvi and Rapasaari mines because their exploration licenses have been purchased from the Finnish state. Agreements between Keliber and the Finnish Government are in place for Leviäkangas and Syväjärvi (dated 19 October 2012) and Rapasaari deposit (signed by the company on 22 October 2014). The following terms apply: • Keliber will pay €0.5 per tonne of ore (that is, the base rate) after the ore has been mined, treated to produce the products and those products sold; • For Syväjärvi and Leviäkangas, the royalty is subject to a price adjustment formula: o Adjusted price = ((Y/Z)*S(P) + (1-S)*(P)) Where: Z = Index3 for Base Period (January 2012) Y = Index for December month preceding the year Royalty is calculated S = Percentage of Price Subject to Adjustment (100%) P = Base unit contract Price (€0.5) The royalty may be adjusted upward or downward based on the change in the Index from the base value to the December month value preceding the year for which the royalty is to be calculated. The base period for calculating the change will be from the January 2012 date of the Agreement. The royalty payment is payable annually and is made by the end of April the following year. • For Rapasaari , the royalty is subject to the following price adjustment formula: o Adjusted price = ((Y/Z)*S(P) + (1-S)*(P)) Where: Z = Index3 for Base Period (September 2014) Y = Index for December month preceding the year Royalty is calculated S = Percentage of Price Subject to Adjustment (100%) P = Base unit contract Price (€0.5) The royalty may be adjusted upward or downward based on the change in the index from the base value to the December month value preceding the year for which the royalty is to be calculated. The base period for calculating the change will be from the effective date of the Agreement. The royalty payment is payable annually and is made by the end of April the following year. 2.2.7 Finnish environmental legislation Finland has adopted a comprehensive regulatory framework on environmental issues. Although mostly regulated through national legislation, a large part of Finnish environmental legislation is from European Union (EU) law, either as directly applicable law or through implementation of EU law. The key national legislation and main environmental regimes in Finland are shown in Table 2-2. 3 For Syväjärvi and Leviäkangas, the Index is the Producer Price Index of the Industry (2000 = 100) and for Rapasaari, the Index is the Producer Price Index of the Industry (2010 = 100). SRK Consulting – 592138 SSW Keliber TRS Page 39 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Table 2-2: Key environmental legislation Applicable Act Aspect governed by the Act Environmental Protection Act (Ympäristönsuojelulaki). Prevention and control of pollution; prevention of generation of waste by certain activities; soil and groundwater conservation and remediation Waste Act (Jätelaki) General prevention of generation of waste and prevention of hazards and harm to human health and the environment Water Act (Vesilaki) Water resource management and control Nature Protection Act (Luonnonsuojelulaki) Nature and landscape conservation Act on Compensation for Environmental Damage (Laki ympäristövahinkojen korvaamisesta) Liability for environmental damage Act on Remediation of Certain Environmental Damage (Laki eräiden ympäristölle aiheutuneiden vahinkojen korjaamisesta) Remediation of damages to biodiversity and certain water systems Act on Environmental Impact Assessment Procedure (Laki ympäristövaikutusten arviointimenettelystä) Environmental impact assessment (EIA) Act on Environmental Impact Assessment of Plans and Programmes of the Authorities (Laki viranomaisten suunnitelmien ja ohjelmien ympäristövaikutusten arvioinnista) EIA concerning certain plans and programmes Land Use and Building Act (Maankäyttö- ja rakennuslaki) Land use and planning Emission Trading Act (Päästökauppalaki) Emissions trading Act on the Use of the Kyoto Mechanisms (Laki Kioton mekanismien käytöstä) Emissions trading Land Extraction Act (Maa-aineslaki). Use and control of certain natural resources Mining Act (Kaivoslaki) Use and control of mining resources Forest Act (Metsälaki) Use and control of forest resources Chemical Act (Kemikaalilaki)x Use and control of forest resources Gene Technology Act (Geenitekniikkalaki) Genetic engineering Nuclear Energy Act (Ydinenergialaki Nuclear power Act on Operating Aid for Power Generation from Renewable Energy Sources (Laki uusiutuvilla energialähteillä tuotetun sähkön tuotantotuesta) Renewable energy/feed-in tariffs Radiation Act (Säteilylaki) Radiation control Key regulatory authorities The main body that develops environmental policy and drafts environmental legislation is the Ministry of the Environment. Other relevant ministries with adjacent competencies are the: • Ministry of Employment and the Economy, which handles policy issues concerning mining and energy (including renewable energy); and • Ministry of Agriculture and Forestry, which handles policy issues concerning the use of water and forest resources. There are several competent authorities that enforce environmental legislation. Generally, the competent supervisory authorities are the regional Centres for Economic Development, Transport and the Environment (Elinkeino- , liikenne- ja ympäristökeskus) (ELY-keskus), and the municipalities. The competent permitting authorities for environmental permits are the Regional State Administrative Agencies (Aluehallintovirasto) and the municipalities. Environmental permitting The Environmental Protection Act governs an integrated permit regime for emissions into air, water and/or soil and the generation of waste. However, an environmental permit does not necessarily cover all activities on site or even all emissions from the site/operations. Under certain circumstances the permit process for a water permit under the Water Act is integrated with the permit process for an environmental permit. Environmental Impact Assessments An Environmental Impact Assessment (EIA) must be performed for projects if: • The project type is listed in the Environmental Impact Assessment Decree, which contains a list of projects (industrial and construction) that are deemed to have considerable environmental impacts.
SRK Consulting – 592138 SSW Keliber TRS Page 40 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 • The competent authority decides that an EIA must be performed due to the considerable environmental impact of the project even if the project is not included in the Decree. In addition to the general EIA legislation that applies to projects, public authority plans and programmes also require an EIA under certain circumstances. The most important ones are listed in a separate government Decree. For planning decisions, municipalities are responsible for assessing the environmental impact of the plan under the land use and planning legislation. In addition to typical environmental impacts, impacts on the local economy must also be assessed. If a project or plan may affect the nature conservation values of a Natura 2000 nature conservation site, the impact must be evaluated before the project or plan can be carried out. 2.3 Mineral Rights [§229.601(b)(96)(iii)(B)(3)(ii)-(iv)] SSW has confirmed to SRK that all legal information in this TRS is correct and valid and that the company in which it has the shareholding (Keliber) has title to the mineral rights and surface rights for the Keliber Lithium Project through its subsidiary Keliber Technology Oy. All the permits – both mining and exploration – are wholly owned by the operating company, Keliber Technology Oy and have been applied/granted for lithium. Compensation to the landowners according to the Mining Act applies to all legally valid mining and exploration permits; compensation for all permit applications or the granted exploration permits will only become due once the permits are legally valid. 2.3.1 Mining Rights As at 31 December 2022, there are two legally valid mining permits, Länttä and Syväjärvi, together totalling some 223.74 ha in extent (Table 2-3). The Rapasaari permit was granted in March 2022, it still needs to become legally valid, the next step in the permitting process. The Finnish Mining Authority (Tukes) is responsible for granting mining and exploration permits; once a permit is granted, there is a period of 37 days during which an appeal against the permit may be lodged with the Administrative Court. If no appeals are lodged, the permit becomes legally valid. If an appeal is lodged, resolution may delay operations by up to 18 months, or longer if the appeal is escalated to the Supreme Administrative Court (up to around 30 months in total). Any person, company or organisation may lodge an appeal, which are usually on environmental grounds (e.g. noise, dust, increased traffic, etc.) Mining safety permits Keliber has an approved mining safety permit for Syväjärvi (Mining permit KL2018: 0001; Environmental permit 36/2019 number: LSSAVI / 3331/2018). The application was completed in March 2021 and signed in October 2021. This would allow Keliber to start site development in spring 2022, which is estimated to require 24 – 28 months to complete. Thereafter, mining is proposed to commence and continue for approximately four years. Keliber intends to apply for a mining safety permit for Rapasaari in 2023 or as soon as possible. 2.3.2 Prospecting Rights Eleven exploration permits with a total area of 1 804.29 ha were valid as at 31 December 2022 (Table 2-3) and applications for a further 28 exploration permits (with a total extent of 5 768.39 ha) had been submitted (Table 2-4). Three exploration permits had lapsed, or were due to lapse, and were reapplied for and are awaiting approval: • Paskaharju (ML2016:0044) expired on 19/05/2022 and was reapplied for on 03/05/2022; • Päiväneva (ML2012:0176) will end on 15/01/2023 and was re-applied for on 16/11/2022 as ML2012:0176-03 but over a smaller area (52.02 ha as opposed to the previous 82.37 ha) to ensure no overlap with the Rapasaari Mining Permit area; and • Rapasaari (L2018:0121) will also expire on 15/01/2023 and was reapplied for on 19/11/2022 as ML2018:0121-02, also over a smaller area (64.90 ha, previously 428.87 ha), for the same reason as Päiväneva. One reservation (Peräneva VA2022:0020) was decided on 19/05/2022 and expires on 04/04/2024. Three additional exploration permits have been granted – Emmes 1, Haukkapykälikkö and Pässisaarenneva – with a SRK Consulting – 592138 SSW Keliber TRS Page 41 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 combined area of 392.71 ha. In all three cases, the permit decision has been appealed and is currently under a legal process in an Administrative Court. Table 2-3: Summary of valid or granted mining and exploration permits as at 31 December 2022 Number Asset Number Status Decision Date Expiry Date Licence Area (ha) Valid Mining Permits 1 Länttä 7025 Legally valid 16/08/2016 20/03/2027 37.49 KL2021:0002 11/02/2022 2 Syväjärvi KL2018:0001 Legally valid 13/12/2018 Until further notice 186.25 KL2021:0003 08/02/2022 3 Rapasaari1 KL2019:0004 Granted 23/03/2022 Until further notice 488.98 Total area 712.72 Valid Exploration Permits 1 Emmes 2 ML2019:0052 Legally valid 30/07/2021 06/09/2024 58.1 2 Karhusaari ML2012:0157 Legally valid 16/12/2019 15/01/2023 167.36 3 Outoleviä ML2019:0011 Legally valid 30/07/2021 06/09/2024 444.65 4 Outovedenneva ML2011:0019 Legally valid 30/07/2021 06/09/2024 68.75 5 Outovesi ML2018:0089 Legally valid 20/03/2020 20/04/2023 144.68 6 Outovesi 3 ML2018:0122 Legally valid 20/03/2020 20/04/2023 12.9 7 Päiväneva ML2012:0176 Legally valid 16/12/2019 15/01/2023 82.37 8 Rapasaari ML2018:0121 Legally valid 16/12/2019 15/01/2023 428.87 9 Roskakivi ML2016:0020 Legally valid 30/07/2021 06/09/2025 227.18 10 Syväjärvi 3-4 ML2018:0120 Legally valid 16/12/2019 15/01/2023 115.75 11 Timmerpakka ML2019:0010 Legally valid 20/03/2020 20/04/2023 53.68 Total area 1 804.29 Valid Reservation 1 Peräneva VA2022:0020 Reservation 19/05/2022 04/04/2024 3 915.16 Total area 3 915.16 Granted Exploration Permits (appealed)1 1 Emmes 1 ML2015:0031 Granted 01/11/2021 19.86 2 Haukkapykälikkö ML2011:0002 Granted 30/07/2021 350.32 3 Pässisaarenneva ML2018:0040 Granted 30/07/2021 22.53 Total area 392.71 Note: 1. Permit decision appealed; under legal process in Administrative Court. SRK Consulting – 592138 SSW Keliber TRS Page 42 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Table 2-4: Summary of exploration permit applications as at 31 December 2022 Number Asset Number Status Application Date Licence Area (ha) 1 Arkkukivenneva ML2021:0045 Pending 31/03/2021 83.78 2 Buldans ML2020:0001 Pending 16/01/2020 105.57 3 Hassinen ML2018:0034 Pending 02/05/2018 300.39 4 Heikinkangas ML2012:0156 Pending 27/05/2019 42.55 5 Hyttikangas ML2018:0035 Pending 02/05/2018 238.08 6 Kellokallio ML2019:0032 Pending 27/04/2019 182.19 7 Karhusaari ML2012:0157-03 Pending 17/11/2022 137.91 8 Keskusjärvi ML2018:0033 Pending 02/05/2018 211.08 9 Kokkoneva ML2018:0055 Pending 16/05/2018 284.85 10 Länkkyjärvi ML2018:0036 Pending 02/05/2018 361.57 11 Leviäkangas 1 ML2013:0097 Pending 05/05/2021 90.69 12 Matoneva ML2018:0041 Pending 08/05/2018 511.54 13 Orhinselkä ML2018:0042 Pending 08/05/2018 222.05 14 Östersidan ML2018:0056 Pending 16/05/2018 204.95 15 Päiväneva ML2012:0176-03 Pending 19/11/2022 52.02 16 Palojärvi ML2018:0091 Pending 08/10/2018 35.55 17 Paskaharju ML2016:0044 Pending 03/05/2022 131.71 18 Peikkometsä ML2018:0023 Pending 21/03/2018 773.44 19 Peuraneva ML2018:0032 Pending 02/05/2018 152.67 20 Rapasaari ML2018:0121-02 Pending 16/11/2022 64.90 21 Ruskineva ML2020:0002 Pending 17/01/2020 739.35 22 Rytilampi ML2011:0020 Pending 03/02/2018 163.21 23 Syväjärvi 2 ML2016:0001 Pending 07/04/2021 71.53 24 Syväjärvi 3-4 ML2018:0120-02 Pending 17/11/2022 115.75 25 Timmerpakka 2 ML2020:0025 Pending 23/04/2020 174.96 26 Valkiavesi ML2018:0031 Pending 02/05/2018 1 037.56 28 Vanhaneva ML2019:0002 Pending 27/09/2018 368.12 29 Vehkalampi ML2018:0022 Pending 22/03/2018 1 138.54 Total area 5 768.39 SRK Consulting – 592138 SSW Keliber TRS Page 43 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Mining and exploration permits as at 31 December 2022 (Source: WSP, 2022) Project No/ 592138 Figure 2.2: Mining and exploration permits as at 31 December 2022
SRK Consulting – 592138 SSW Keliber TRS Page 44 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 2.3.3 Surface rights Valid exploration permits include the right of access to the land, while legally valid mining permits require the holder to separately acquire the surface rights to the land through purchase, lease or expropriation. Keliber owns land at both Syväjärvi and Outovesi: • Syväjärvi: 47.39 ha (~28%) of the current mining area of 166.3 ha; and • Outovesi: 41.73 ha (~20%) of current claim areas of 209.67 ha. The remainder of the land covering the proposed mining areas is owned by private owners. Keliber leases the land (125 149 m2) for the Kokkola Chemical Plant from Kokkolan Energia Oy with a fixed-duration agreement until 31 December 2049; thereafter the tenancy will continue as valid until further notice. An option for lease of an additional 33 589 m2 area is included in the agreement. 2.3.4 Legal proceedings SRK is not aware of any legal proceedings against Keliber. 2.3.5 Potential risks to tenure The length of time required for the authorities to process the exploration and mining permit applications is unknown. A legal due diligence exercise to understand the permitting risks is currently being completed by Keliber; the resolution of this risk is not required for the declaration of Mineral Resources. Uncertainty regarding potential objections by the public and/or authorities to the award of tenure for each of the applications exists. The relevance of the uncertainty is that some of the applications, or specific applications, could either significantly be delayed or are wholly unsuccessful, with knock-on effects to the project. 2.4 Property encumbrances and permitting requirements [§229.601(b)(96)(iii)(B)(3)(v)] 2.4.1 Environmental, water and waste authorizations, licences and permits Keliber’s operations will be governed by framework legislation that includes several laws, acts, decrees, and permits. The legislation and permits that steer Keliber operations are listed in Keliber’s compliance register. The environmental permitting status of the Keliber Project as of December 2022 is summarised in Table 2-5. Key laws and regulations relevant to the Keliber operations include: • Mining legislation including the Mining Act (621/2011); • Environmental Protection Act (527/2014) including the Environmental Protection Decree (713/2014), the Water Act (587/2011) and Environmental Impact Assessment Procedure Act (252/2017); • Dam Safety Act 494/2009; • Chemical legislation including Chemical Act (599/2013) and Act on the Safe Handling and Storage of Dangerous Chemicals and Explosives (390/2005); • Government Decree on Extractive Waste (190/2013 as amended); • Waste Act (646/2011) and Waste Decree (179/2012); • Nature Conservation Act (1096/1996)/Natura 2000 (Appropriate Assessment); • Fire safety legislation including Rescue Act (379/2011); • Land use and building legislation including the Land Use and Building Act (132/1999); • Air Pollution Control Decree (79/2017); • Degree on the Safe Production and Handling and Storage of Explosives (1101/2015); and • Forest Act (1093/1996). Permits guiding operations include: • Environmental permit; SRK Consulting – 592138 SSW Keliber TRS Page 45 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 • Water permit; • Mining permit; • Mining safety permit; • Building permit; • Permit for handling and storage of dangerous chemicals; • Permit for storage of explosives; and • Exploration permit. Table 2-5: Environmental permitting status as at 31 December 2022 Site Permit Status Date Granted Syväjärvi mine Environmental Impact Assessment Finalised 29.3.2021 Environmental and water permit Valid 20.2.2019 Exception permit to moor frogs Valid 1.2.2020 Exception permit for diving beetles Valid 21.7.2020 Mining permit 1 Valid 13.12.2018 The right of use of the mining area Valid 9.8.2021 Mining Safety Permit Valid 13.10.2021 Rapasaari mine Environmental Impact Assessment Finalised 29.3.2021 Environmental permit Valid 28.12.2022 Mining Permit Granted, but not yet legally valid 23.03.2022 Mining Safety Permit Not started Länttä mine Environmental Impact Assessment Finalised 28.6.2018 Environmental permit Valid 7.11.2006 Mining Permit Valid 16.8.2016 Mining Safety Permit Not started Outovesi mine Environmental Impact Assessment Finalised 29.3.2021 Environmental permit Not started Mining Permit Not started Mining Safety Permit Not started Päiväneva concentrator Environmental Impact Assessment Finalised 29.3.2021 Environmental and water permit Application submitted 30.6.2021 Mining Permit (included in Rapasaari mining area) Application submitted 14.4.2021 Land use plan, local detailed plan In progress Building permit Not started Chemical permit Not started Keliber Lithium Hydroxide Refinery Environmental Impact Assessment Finalised 30.6.2021 Environmental permit Application submitted 4.12.2020 Building permit Finalised Chemical Permit Not started Keliber has completed all relevant EIA procedures to proceed with the Project, as discussed below. Keliber holds a valid environmental permit for the Syväjärvi mining operations and a water permit for dewatering lake Syväjärvi and lake Heinäjärvi. A valid permit states that the permit decision issued by Regional State Administrative Agency (AVI) was appealed and appeals were processed in the Vaasa Administrative Court. The Court ruled against appeals and kept AVI’s permit decision in force on June 16th, 2021. There were no appeals made to SAC against the Vaasa Administrative Court Decision. The Syväjärvi environmental permit became final in July 2021. Keliber holds an environmental permit for Länttä, issued in 2006. The permit is valid for mining and operations described in the permit application. If operations or excavation volumes increase, Keliber may SRK Consulting – 592138 SSW Keliber TRS Page 46 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 need to apply for a new environmental permit. The Länttä mine is not scheduled to commence before 2037 so detailed engineering has not been started yet. The Rapasaari mine environmental permit application was submitted to AVI on June 30th, 2021. The Päiväneva concentrator environmental permit was submitted to AVI on June 30th, 2021. Concentrator operations require a water permit for raw water intake from river Köyhäjoki and that permit application was also submitted to AVI on June 30th, 2021. A decision by AVI is expected in the summer or fall of 2022. Keliber received environmental permits for the Rapasaari Mine and Päiväneva Concentrator in December 2022 (Environmental permit 208/2022 number: LSSAVI/10481/2021, LSSAVI/10484/2021). These permits are currently going through an appeal process. For the Lithium Hydroxide Refinery located in Kokkola, an environmental permit application was submitted to AVI on December 4th, 2020. The environmental permit has been approved in early 2022 but is currently under appeal. 2.5 Summary of permitting status The summary of the current permitting status (Table 2-6) has been compiled from information supplied by Hans Snellman, a Nordic law firm with offices in Helsinki and Stockholm and Keliber’s legal advisors and updated for the recent granting of the Rapasaari mining permit. Table 2-6: Summary of permitting status - 31 December 2022 Site Mining Permit Mining Safety Permit Proceedings establishing Mining Area EIA Environmenta l Permit Zoning Land Use Rights Building Permits Syväjärvi mine Valid issued 13/12/2018 Valid - issued 13/10/2021 Valid 09/08/2021 Statement 29/03/2021 Valid - issued Secured Secured N/a, unless buildings to be constructed Syväjärvi - auxiliary area Valid issued 08/02/2022 Valid 17/05/2022 Secured Rapasaari mine Granted 22/03/2022 Under Appeal After mining permit finalised Started 26/04/2022 Statement 29/03/2021 Granted (Under Appeal) Secured In Progress N/a, unless buildings to be constructed Päiväneva concentrator Included in Rapasaari permit After mining permit finalised Started 26/04/2022 Statement 29/03/2021 Granted (Under Appeal) Secured In Progress Finalised Kokkola Lithium Hydroxide Refinery N/a N/a N/a Statement 30/03/2021 Valid - issued City plan Secured Finalised Note: N/a = Not applicable Completed items shown in green; pending items in orange and outstanding items in red, while items that do not apply have no fill. 2.6 Significant factors and risks affecting access, title [§229.601(b)(96)(iii)(B)(3)(vi)] There are no known risks affecting access. The granted mining permit for Rarpasaari is under appeal at the Administrative Court; similarly, the granted exploration permits for Emmes 1, Haukkapykälikkö and Pässisaarenneva are also under appeal, Operational delays may be up to approximately 18 months. Appeals may be extended to the Supreme Administrative Court, in which case, the delays could be extended for a further 12 months. SRK Consulting – 592138 SSW Keliber TRS Page 47 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 3 ACCESSIBILITY, CLIMATE, LOCAL RESOURCES, INFRASTRUCTURE AND PHYSIOGRAPHY [§229.601(b)(96)(iii)(B)(4) 3.1 Topography, elevation and vegetation [§229.601(b)(96)(iii)(B)(4)(i)] The average altitude for Central Ostrobothnia is 75 mamsl; the topography of the project area is relatively flat with the total difference in elevation between the various sites being in the order of 40 m. The lowest site is Rapasaari at 82.7 mamsl while the highest is Länttä at 122.0 mamsl. The Perhonjoki River flows north-northeast through the area, decanting into the Gulf of Bothnia north of Kokkola. Numerous streams and lakes of all sizes occur throughout the area. The land is cultivated, especially along the river courses, with most of the remaining land covered with forest. There is no permafrost at these latitudes. The overburden thickness at the mine sites varies in thickness from zero at Syväjärvi and Länttä to 20 m at Rapasaari: • Syväjärvi: 0 – 10 m; • Rapasaari: 4 – 20 m; • Länttä: 0 – 8 m; • Outovesi: 7 - 13 m; • Leviäkangas: to be determined; and • Tuoreetsaaret: to be determined. 3.2 Accessibility [§229.601(b)(96)(iii)(B)(4)(ii)] Figure 2.1 shows the location of the various elements of the Keliber Lithium Project. The chemical plant is situated in KIP, 6 km northeast of the city centre of Kokkola and two kilometres from Kokkola port on the Gulf of Bothnia; the road and rail links between the two are good. Kokkola-Pietarsaari Airport is approximately 13 km south of the city and is serviced by regular Finnair flights as well as charter flights. The Päiväneva concentrator and the proposed mining areas are located to the north, northeast and east of the city of Kaustinen, in the municipalities of Kruunupyy, Kokkola and Kaustinen in the Central Ostrobothnian region. KIP and the concentrator are approximately 68 km apart. Kokkola and Kaustinen are connected by national road 13 and are approximately 46 km apart. The various mine sites are located close to the Päiväneva concentrator; distances and directions are given from the concentrator site: • Syväjärvi(Kokkola and Kaustinen municipalities) – 3 km north-northeast; accessible via paved national road 63 and gravel forestry road; • Rapasaari (Kokkola and Kaustinen municipalities) – 1.5 km northeast; accessible via paved national road 63 and gravel forestry road; • Länttä (Kokkola municipality) – 25 km east-southeast; accessible via paved national road 63 and local road 18097 (approximately first two kilometres are gravel); • Outovesi (Kaustinen municipality) -10 km northwest; accessible via paved national road 63 and gravel forestry road; • Emmes (Kruunupy municipality) – 20 km west-northwest; accessible via gravel forestry road, paved national road 63, Emmeksentje road and gravel local road 17947; • Leviäkangas; (Kokkola and Kaustinen municipalities) – 4.5 km northwest; accessible via paved national road 63 and gravel forestry road ; and • Tuoreetsaaret (Kokkola and Kaustinen municipalities) – 1.5 km northeast; accessible via paved national road 63 and gravel forestry road .
SRK Consulting – 592138 SSW Keliber TRS Page 48 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 3.3 Climate [§229.601(b)(96)(iii)(B)(4)(iii)] The climate in Central Ostrobothnia is categorized as subarctic with severe winters, cool summers and precipitation throughout the year; it is classified as Dfc in the Köppen climate classification system. Winters are long, freezing, snowy and overcast while summers are short and partly cloudy. The coldest month is January (average temperature of -8°C) and the warmest July (average temperature of 19°C). Average annual precipitation is approximately 35 mm with July-August being the wettest (~43 mm) and the driest is March-April (~25 mm). Rain is most common between March and January, while snow occurs frequently between October and April, with the most snow falling in January (average of 20 cm). The windier part of the year is from September to March, with the windiest month being December and the least windy being July. Daylight hours vary from four hours in December - January to 20 hours in June - July. Typically, in Nordic countries operations continue in subarctic conditions at Temperatures below -20°C. It is thus expected that Keliber will operate continually during the year. The Rapasaari and Syväjärvi properties were visited during January 2023, and during this time exploration drilling continued and the properties were accessible by the newly constructed road that connects the properties to the public road. 3.4 Local resources and infrastructure4 [§229.601(b)(96)(iii)(B)(4)(iv)] Kokkola Kokkola is the largest city of Central Ostrobothnia with approximately 48 000 people; the Kaustinen municipality has around 4 200 people (2020 data). There are two institutes of tertiary education in Kokkola: The Kokkola University Consortium Chydenius and the Centria University of Applied Sciences. High-level research in materials chemistry including lithium-ion battery materials is undertaken in the department of applied chemistry at Chydenius. Centria offers a Bachelor-level degree programme in environmental chemistry and technology, amongst others. Seven vocational schools and an adult education unit can be found in Kokkola, under the Federation of Education in Central Ostrobothnia, which arranges vocational upper secondary education in the region, such as in process technology. The Keliber chemical plant will be located in the KIP, which has a significant concentration of chemical industry installations: at least 17 industrial operators and more than 60 service companies. Seven hundred hectares of the KIP is zoned for use by the heavy chemical industry. Service enterprises provide commodity and sewage networks, pipe bridges, railways, a factory fire brigade and security. The chemical plant will be immediately adjacent to several important resources such as water, steam, electricity, heat, gas (for example, CO2) and acids (for example, sulfuric acid), which are all produced in the KIP. The Port of Kokkola is the largest port serving the mining industry in Finland and includes general port facilities for containers, breakbulk cargoes and so-called light bulk, such as limestone. The port is open all year round and has an All-Weather Terminal (AWT) mainly for containers and breakbulk cargo and a Deep-Water Port for bulk cargoes. Kaustinen Potable water is available from the Kaustinen municipality water pipeline and the Pirttikoski hydroelectric power plant on the Perhonjoki River in Kaustinen supplies power to the main 110 kV power line. The area is also serviced by mobile phone networks from all the main Finnish service providers, as well as a fibre optic network from a local service provider. Planned staffing levels The planned staffing levels at the various parts of the project are as follows: • Mine: 6 (the bulk of the activities will be done by a contractor); • Concentrator: 33; 4 WSP, 2022 SRK Consulting – 592138 SSW Keliber TRS Page 49 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 • Chemical plant: 51; • Maintenance: 18; • Other production (e.g., laboratory, procurement, etc): 23; • Exploration and geology: 6; and • Management, support and administration: 17; • Total: 154 SRK Consulting – 592138 SSW Keliber TRS Page 50 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 4 HISTORY [§229.601(b)(96)(iii)(B)(5)] 4.1 Previous operations, operators [§229.601(b)(96)(iii)(B)(5)(i)] None of the properties have previously been mined, although the mining rights to the Länttä, Emmes and Syväjärvi deposits were first owned by Suomen Mineraali Oy, then by Paraisten Kalkkivuori Oy and from the early 1960s to the early 1980s by Partek Oy. These rights expired in 1992 and the areas were unclaimed until 1999, when Olle Siren, together with private partners, claimed the Länttä deposit and later the Emmes deposit (Table 4-1). From 2003 to 2012, the Geological Survey of Finland (GTK) held the ownership of the Syväjärvi and Rapasaari deposits. Table 4-1: Previous operators Deposit Date Operator Länttä, Emmes, Syväjärvi, Leviäkangas 1960 – 1968 Suomen Mineraali Oy 1963 - 1999 Paraisten Kalkkivuori Oy (later Partek Oy) All 1992 - 1999 Unclaimed Länttä 1999 Olle Siren and private partners Emmes After 1999 Olle Siren and private partners Syväjärvi, Leviäkangas, Rapasaari 2003 - 2012 GTK Länttä, Emmes, Rapasaari, Syväjärvi, Outovesi, remaining exploration areas* Keliber (previously known as Keliber Resources Ltd.) Tuoreetsaaret 2020 - 2022 Keliber (previously known as Keliber Resources Ltd.) Note: 1. Table 2-3 and Table 2-4 contain the details of the mining and exploration permits. 2. Paraisten Kalkkivuori Oy acquired Suomen Mineraali Oy in 1959; both companies operated in the same lithium-potential area, but under the same umbrella. 4.2 Exploration and development work [§229.601(b)(96)(iii)(B)(5)(ii)] Since the discovery of spodumene and beryl mineralisation in the Kaustinen region in the late 1950s, the area began to see systematic exploration being initiated in the 1960s by Suomen Mineraali Oy and Paraisten Kalkkivuori Oy. Due to the lack of outcrop throughout most of the area, surface exploration methods were restricted to spodumene/pegmatite boulder hunting and then using these results to delineate the source of origin for the boulder fans using palaeo glacial directions. Apart from the Länttä deposit (discovered as outcrop), this method proved highly successful in the discovery of the Emmes and Syväjärvi deposits by early operators. Between 2003 and 2012, GTK were also very active in the area, with exploration work including boulder mapping, geophysical surveys, till sampling, re-analysis of historical regional till samples, percussion drilling and diamond core drilling. This work was successful in the discovery of the Rapasaari deposit as well as further delineation of the Syväjärvi deposit. Keliber’s involvement in the project began in 1999, when a group of investors, led by Mr Olle Siren began evaluation of the Länttä deposit, where drilling commenced in 2004. Keliber then extended its exploration efforts to the rest of the Kaustinen region where it has completed acquisition of exploration rights and extensive drilling programs over all of the deposits including the discovery of the Outovesi deposit in 2010. GTK carried out an extensive areal geochemical till sampling programme covering the whole of Finland during the 1970s and 1980s. At that time, no analysis for lithium was conducted. Later, GTK re-analysed the old till samples and large geochemical anomalies were discovered in the Kaustinen area. Some of the known deposits are reflected in lithium anomaly maps, but spotty anomalies extend far outside of the known deposits, especially to the northwest (WSP 2022b). During 2004 - 2011, GTK carried out 15.5 line kilometres of gravity survey and 4.4 km2 of gravity and magnetic ground geophysical surveys in seven different exploration areas (Table 4-2). A slingram survey SRK Consulting – 592138 SSW Keliber TRS Page 51 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 was also conducted at Rapasaari. Ground geophysics was surveyed to support geological mapping and to define the borders of the spodumene pegmatites. High-resolution, low-altitude airborne geophysics data for 2004 were also used (Ahtola et al 2015). Table 4-2: Summary of the sampling and ground geophysics (after Ahtola et al 2015) Drilling target Period Number of diamond drill holes Ground geophysics Till sampling (number of samples) RC drilling (number of samples) Total length (m) Line km/km2 Method* Leviäkangas 2004 - 2008 22 2 032 1 km2 mg+ gr 60 Syväjärvi 2006 - 2010 24 2 547 1 km2 mg+ gr 56 Rapasaari 2009 - 2012 26 3 653 2.2 km2 mg+sl+gr 508 Total 72 8 232 4.4 km2 508 116 Note: * mg = magnetic, sl = slingram, gr= gravity The first drilling programmes were undertaken by Suomen Mineraali Oy in 1961 and were executed using small drill rigs. From 1966 to 1981, a core diameter of 32 mm was used by Suomen Mineraali Oy and Partek Oy. These small diameter drilling programmes were executed at Emmes, Länttä, Leviäkangas and Syväjärvi in the 1960s, 1970s and at the beginning of the1980s (WSP, 2022b). The historical drilling activities undertaken by these operators are summarized in Table 6-1, along with the work undertaken under the ownership of Keliber Oy.
SRK Consulting – 592138 SSW Keliber TRS Page 52 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 5 GEOLOGICAL SETTING, MINERALISATION AND DEPOSIT [§229.601(b)(96)(iii)(B)(6) 5.1 Regional, local and project geology [§229.601(b)(96)(iii)(B)(6)(i) (ii)] The Keliber Project is located within the Kaustinen Lithium Pegmatite Province that covers an area of 500 km2 in western Finland. Here the host rocks belong to the Palaeoproterozoic (1.95 – 1.88 Ga) age Pohjanmaa Belt that forms a 350 km long by 70 km wide arcuate belt located between the Vaasa Granite Complex to the west and the Central Finland Granitoid Complex to the east (Vaasjoki et.al., 2005). The Pohjanmaa Belt is predominantly comprised of supracrustal rocks comprising micas schists/metasediments, gneisses, metavolcanics with metamorphic grades varying from low to upper amphibolite facies (Alviola et al., 2001). The northern parts of the Pohjanmaa Belt have been intruded by several Lithium-Caesium-Tantalum (LCT)-type pegmatites with a majority of those belonging to the Kaustinen lithium province being of the albite/spodumene type (Cerny and Ercit, 2005). These pegmatites (dated at 1.79 Ga) were intruded into the Pohjanmaa metasediments just after peak regional metamorphism, with the source rocks of the pegmatites being the large pegmatitic granites and granites found within the Kaustinen region (Figure 5.1 and Figure 5.2). At least ten individual pegmatites have been discovered to date within the Kaustinen lithium province, with nearly all of them being evaluated using drilling methods only, as outcropping pegmatites and their host rocks are rare, most being covered by overburden comprising surficial sediments (glacial till). Most of the pegmatites have intruded at high angles or subparallel to host rock foliations, with nearly all displaying similar mineralogy, being dominated by feldspar, quartz, spodumene and muscovite. Host rocks in the region are dominated by mica schists, coarse-grained metagreywackes and intermediate to mafic metavolcanic rocks, all belonging to the Pohjanmaa Belt (Figure 5.1). Historical exploration supported by more recent drilling by GTK and Keliber has (to date) resulted in the delineation of five discrete LCT pegmatite deposits, viz. Syväjärvi, Rapasaari, Länttä, Emmes and Outovesi (Figure 5.2). Each deposit is characterised by a series of pegmatites, veins and dykes, with intrusion geometry often being controlled by regional structural controls as well as host rock rheology. Due to the ubiquitous cover of overburden/till/sediments covering most of the region as a whole, project and regional scale geological maps, stratigraphic columns and regional geological cross sections are not available over the region or any of the deposits. However detailed drilling by both GTK and Keliber have been able to delineate most of the larger individual pegmatites to a relatively high level of confidence. It is noted that it is a SEC requirement to include a stratigraphic column and regional geological cross section of the project area/s. The intrusion type and style of deposit being considered, i.e., vein pegmatite and dyke intrusions, means that the inclusion of a stratigraphic column and section in this TRS is not considered relevant nor can it provide any real technical guidance within the context of the project geological setting being described in the TRS. 5.1.1 Syväjärvi geology The Syväjärvi deposit is located beneath a cover of sandy till that attains an average thickness of 5 m. Outcrop within the project is restricted to an isolated exposure of a host lithology: plagioclase porphyrite (metavolcanic). The geological model describing the attitude and thicknesses of the various pegmatites and contact relationships with host rocks was derived entirely from surface drilling. Here six modelled spodumene-bearing pegmatites veins have intruded into mica schists, metagreywackes and metavolcanics following a broad antiformal structure forming “saddleback” type reefs. This has resulted in a series of shallow northerly plunging pegmatite veins, the largest of these attaining thicknesses of up to 20 m in places. The strike length totals 365 m for all veins, extending approximately 720 m down dip and to a maximum depth below surface of 160 m. Due to variability of the pegmatite/s strikes and dips, true pegmatite thicknesses were generally 70 - 80% of drill length. The main pegmatite is relatively flat-lying with shallow to horizontal dips (10˚ – 30˚) and plunging to the north (Figure 5.3). Pegmatite boundaries are typically sharp with the frequent development of weakly mineralised or un-mineralised zones of muscovite- rich pegmatite within and along the margins of the pegmatites. SRK Consulting – 592138 SSW Keliber TRS Page 53 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 In 2016, Keliber developed an inclined tunnel into the deposit in order to provide a bulk sample for metallurgical test work. Total length of the tunnel was 71 m, including a 17 m intersection of the main pegmatite. Here the pegmatite comprised coarse-grained spodumene, light grey to green in colour with individual spodumene laths displaying lengths varying from 3 cm to as much as 70 cm. Mineralogical analyses by GTK has shown that the pegmatites are comprised of albite (37%), quartz (27%), potassium feldspar (16%), spodumene (13%) and muscovite (6%). Accessory minerals are apatite (fluorapatite), Nb- Ta-oxides (Mn- and Fe-tantalite), tourmaline (schorl), garnet (almandine), arsenopyrite and sphalerite. SRK Consulting – 592138 SSW Keliber TRS Page 54 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Regional geology of Keliber (modified after Ahtola et al., 2015) Project No. 592138 Figure 5.1: Regional geology of Keliber (modified after Ahtola et al., 2015) SSW Keliber Lithium Project Project Geology of the Keliber Lithium Project (modified after Ahtola et al., 2015) Project No. 592138 Figure 5.2: Project Geology of the Keliber Lithium Project (modified after Ahtola et al., 2015) SRK Consulting – 592138 SSW Keliber TRS Page 55 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Syväjärvi - 3D view of modelled pegmatites looking west, with photo showing exposed pegmatite in exploration tunnel (Photo Source: Keliber Oy) Project No. 592138 Figure 5.3: Syväjärvi - 3D view of modelled pegmatites looking west, with photo showing exposed pegmatite in exploration tunnel 5.1.2 Rapasaari geology The Rapasaari Lithium deposit is covered by a variable cover of till/overburden ranging from 3 m to 20 m in thickness, and thus outcrop is rare. In some cases, till is also overlain by peat that can reach thickness of up to 2 m. The Rapasaari deposit represents a curvilinear, structurally controlled series of thirty-three individually modelled pegmatites that exhibit variable thicknesses, resulting in a series of bifurcating and boudinaged lenses and veins that follow a south-easterly plunging synformal structure. This has resulted in a series of northwest-southeast striking and south-westerly dipping pegmatites (Rapasaari East) and west - east striking, south dipping pegmatites (Rapasaari North) (Figure 5.4). Pegmatites are generally intruded parallel to the host rocks that are primarily composed of mica schists, metagreywackes and metavolcanics. In certain places the mica schists are graphitic and sulfide-bearing, but these are generally isolated. Pegmatite boundaries are typically sharp, with the frequent development of weakly mineralised or un- mineralised zones of muscovite-rich pegmatite within and along pegmatite margins. The style of pegmatite emplacement has also resulted in the frequent inclusions/xenoliths/rafts of country rocks throughout all the modelled pegmatites at Rapasaari, with these representing internal dilution to the modelled pegmatites. The three largest modelled pegmatites vary in thickness from 10 m to 20 m, with most of the minor (modelled) pegmatites having thicknesses of less than 10 m. The strike extent totals 1 250 m for all veins - approximately 730 m in the primary dip orientation (east – west) - and to a maximum depth below surface of 240 m. Due to variability of the strike and dip of the pegmatite/s, true pegmatite thicknesses were generally 70 - 90% of drill length. Mineralogical analyses by GTK have shown that the pegmatites comprise albite (37%), quartz (26%), potassium feldspar (10%), spodumene (15%) and muscovite (7%). Accessory minerals are apatite (fluorapatite), zinnwaldite, Nb-Ta-oxides (Mn- and Fe-tantalite), beryl, tourmaline, fluorine, garnet (grossular), andalusite, calcite, chlorite, Mn-Fe-phosphate, arsenopyrite, pyrite, pyrrhotite and sphalerite. In general, spodumene crystals are light greyish-green in colour, with the lengths of minerals varying from 2 cm to 10 cm.
SRK Consulting – 592138 SSW Keliber TRS Page 56 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Rapasaari - 3D view of modelled pegmatites looking southwest Project No. 592138 Figure 5.4: Rapasaari - 3D view of modelled pegmatites looking southwest 5.1.3 Länttä geology The Länttä deposit is covered by a relatively thin veneer of surficial sediments and till ranging from 1 m to 7 m in thickness. The deposit was discovered following road excavation work in the 1950s. Drilling completed by historical operators (Suomen Mineraali Oy and Partek Oy ) and Keliber delineated two parallel- trending pegmatite veins with a 400 m north-easterly strike and steep south-easterly dips to a maximum depth of 180 m below surface, extending approximately 100 m southeast of the outcrop location (Figure 5.5). The pegmatites reach an individual maximum thickness of 10 m, and often show localised bifurcating and boudinaging, resulting in the incorporation of inclusions and xenoliths of metavolcanic host rocks into the pegmatites. Due to variability of the strikes and dips of the pegmatite/s, true pegmatite thicknesses were generally 80 - 90% of drill length. Overburden stripping completed in 2010 exposed the pegmatite veins on surface, confirming their boudinaged and variable widths. Host rocks to the pegmatites are metavolcanic rocks containing lenses of metagreywacke schists and plagioclase porphyrite rocks, with pegmatites intruding parallel to prevailing cleavage and bedding of the host rocks. Contacts with the pegmatite and host rocks are sharp and are typically characterised by the development of a tourmaline- rich band that breaks upon contact. Mineralogical analyses by GTK shows that the pegmatites are comprised of albite (40%), quartz (15%), potassium feldspar (15%), spodumene (15%) and muscovite (2%). Accessory minerals include apatite, garnet, beryl, tourmaline, and columbite-tantalite. Spodumene crystals are coarse grained, elongated and lath-shaped, with lengths ranging from 3 cm to 10 cm, but often reaching 30 cm. SRK Consulting – 592138 SSW Keliber TRS Page 57 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Länttä - 3D view of modelled pegmatites looking northeast Project No. 592138 Figure 5.5: Länttä - 3D view of modelled pegmatites looking northeast 5.1.4 Emmes geology A majority of the Emmes deposit is located under Lake Storträsket close to the village of Emmes. Overburden thickness are highly variable reaching 10 m thickness under the lake and as much as 20 m closer to the village. Drilling to date has delineated a single pegmatite vein 400 m long, striking southeast- northwest with variable dips to the southwest, to a distance of 110 m from the outcrop and a depth of 170 m below surface (Figure 5.6). The Emmes pegmatite reaches a maximum thickness of 20 m in places and is intruded into mica schists containing occasional graphitic and sulfidic phases as well as metagreywackes. Spodumene is distributed evenly throughout the pegmatite and shows some alteration to muscovite along the pegmatite margins. Contacts with the host rocks are sharp, with true pegmatite thicknesses being generally 70 - 90% of drill length. Similar to the other deposits, spodumene is light grey to green in colour and the pegmatites modal mineralogy is very similar to that of the other pegmatite deposits, i.e., being dominated by feldspar, quartz, spodumene and muscovite. No inclusions or xenoliths of country/host rock has been identified within the Emmes pegmatite. SRK Consulting – 592138 SSW Keliber TRS Page 58 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Emmes - 3D view of modelled pegmatites looking northwest Project No. 592138 Figure 5.6: Emmes - 3D view of modelled pegmatites looking northwest 5.1.5 Outovesi geology The Outovesi deposit was discovered by Keliber in 2010 and is covered by surficial till sediments that average 10 m in thickness. Keliber’s drilling delineated a single pegmatite vein some 400 m long and reaching a maximum thickness of 10 m (Figure 5.7). The pegmatite strikes northeast-southwest for a modelled length of 360 m, with variable dips to the northwest. The vein dips steeply (~80°) to a depth of 75 m below surface. Host rocks are dominated by homogenous mica schists and metagreywackes, with the northern parts of the deposit being hosted by more graphite-rich schists. The Outovesi pegmatite has intruded almost at right angles to the host rock fabric, which is quite different to that at Länttä and Rapasaari deposits, where the pegmatites have generally intruded parallel to host rock fabrics. Contacts with the host rocks are sharp, with true pegmatite thicknesses being generally 90% of drill length. Although no detailed mineralogy has been completed over Outovesi, the modal mineralogy is anticipated to be very similar to the other deposits, being dominated by albite, quartz, potassium feldspar, spodumene and muscovite. Spodumene crystals are generally light grey-green in colour with individual spodumene minerals reaching lengths of between 2 cm to 10 cm. It is noted that a later stage, possibly hydrothermal, overprint has resulted in a variable zone of alteration close to the pegmatite contacts, and this has resulted in the alteration of spodumene to a lower tenor Li-bearing muscovite. SRK Consulting – 592138 SSW Keliber TRS Page 59 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Outovesi - 3D view of modelled pegmatites looking northeast Project No. 592138 Figure 5.7: Outovesi - 3D view of modelled pegmatites looking northeast 5.1.6 Leviäkangas geology The Leviäkangas lithium pegmatite deposit is located in the Kaustinen Municipality of western Finland some 5 km south of Kaustinen town (Figure 5.2) It comprises three separate spodumene pegmatite veins that are conformably intruded into a mica-schist host rock (Figure 5.8). There is a possibility that these bodies may belong to one vein that has been structurally dislocated. The strike of the pegmatite veins varies between north and north-northwest. The veins are dipping to the west at an angle between 50°and 60°. The thickness of the veins varies from a few metres to 12 m. The overburden is formed by till with some peat at the surface at Leviäkangas and varies in thickness from 5 m to 10 m. Close to, and at the contact with, the wall rocks, the spodumene in the pegmatite is altered to muscovite. This persists for a few tens of centimetres up to one and a half metres. In addition, there are a few narrow (0.5 – 3 m) internal waste zones in the pegmatite where the spodumene is replaced by muscovite so that the Li2O grade is below the cut-off grade. Spodumene typically occurs as coarse grained, light greyish-green lath-shaped crystals between two and 10 cm long and orientated perpendicular to the contacts of the veins with the wall rock. The pegmatite consists predominantly of albite, quartz potassium feldspar (orthoclase), spodumene and muscovite. The most recent report on Leviäkangas (Lovén and Meriläinen, 2016), states that the deposit has been defined by 123 drill holes with a total length of 6 823.5 m. The pegmatite has been sampled in 572 intervals and the samples were analysed for Li, Nb, Be and Ta that are also expressed in the oxide forms as Li2O, Nb2O5, BeO and Ta2O5. The analyses were done by firstly fusing the crushed and milled sample with sodium peroxide flux to form a glass, which is then dissolved and analysed using the Inductively Coupled Plasma (ICP) Optical Emission Spectroscopy (OES) measurement method.
SRK Consulting – 592138 SSW Keliber TRS Page 60 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Leviäkangas - vertical section view of modelled pegmatites looking east Project No. 592138 Figure 5.8: Leviäkangas - vertical section view of modelled pegmatites looking east 5.1.7 Tuoreetsaaret geology The Tuoreetsaaret lithium pegmatite deposit is also located in the Kaustinen Municipality of western Finland (Figure 5.2). This deposit was discovered by Keliber using a combination of geological, geochemical and geophysical data that led to the first intersection by diamond core drilling in March 2020. The deposit comprises five lithium-bearing pegmatite vein-like bodies intrusive into a set of rock units including intermediate meta-tuffite, plagioclase porphyrite, mica schist and sulphide-bearing mica schist. The hanging wall is generally formed by intermediate meta-tuffite and the footwall by mica schist and sulphide-bearing mica schist. Plagioclase porphyrite generally forms the middling between the pegmatite veins. The pegmatite veins and their wall rocks are covered by 5 m to 10 m of glacial till with peat at the top. The pegmatite vein-like bodies at Tuoreetsaaret range in true thickness from 3 m to 25 m. The individual pegmatite veins are steeply dipping to the east (Figure 5.9), trending north-south, and have a confirmed strike length of 100 m to 300 m. The lithium grains (1 mm to 3 mm in length) are significantly smaller than at Leviäkangas, but the grain size does not differ much between the different veins intersected. Payne (2022) states that the Tuoreetsaaret ore body model has been based on 50 diamond drill holes, of which 16 intersected the mineralisation. The drill core diameter is 50.5 mm, and it was typically sampled at 2 m intervals within the pegmatite with boundaries sampled to the lithological contacts. The core was halved by diamond saw and one half core was submitted for chemical analysis. The samples were fused after crushing and milling with sodium peroxide, then dissolved and analysed by ICP OES. A 27-element suite was routinely reported with a detection limit for Li of 0.001%. SRK Consulting – 592138 SSW Keliber TRS Page 61 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Tuoreetsaaret – 3D view of modelled pegmatites looking northwest Project No. 592138 Figure 5.9: Tuoreetsaaret – 3D view of modelled pegmatites looking northwest 5.1.8 Mineralogy and geo-metallurgy All of the pegmatites that have been discovered and evaluated to date within the Kaustinen area have very similar mineralogy: they are dominated by albite (37 - 41%), quartz (26 - 28%), K-feldspar (10 - 16%), spodumene (10 - 15%) and muscovite (6 - 7%). Internal pegmatite zonation as seen in many other similar LCT-type pegmatites is absent from the Kaustinen pegmatites, with spodumene being the only lithium- bearing mineral that is of economic interest. Other lithium-bearing minerals such as petalite (LiAlSi4O10), lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2), montebrasite-amblygonite (LiAl(PO4)(OH,F) - LiAl(PO4)F), Lithiophilite (Li(Mn,Fe)PO4: LiFePO4 – LiMnPO4), Zinnwaldite (KLiFeAl(AlSi3)O10(OH,F)2) and Elbaite (Tourmaline) (NaLi2.5Al6.5(BO3)3Si6O18(OH)4) have been only found in minor or trace quantities. Despite spodumene mineralisation being generally homogeneously distributed throughout most of the pegmatites, the inclusion or incorporation of host rock xenoliths and wall rock material through dilution will impact the metallurgical recovery of spodumene during flotation and metallurgical processing. This will require careful selective mining supported by optical or density sorting methods to mitigate the impacts of dilution on the recovery of spodumene. 5.2 Deposit type [§229.601(b)(96)(iii)(B)(6)(ii-iii)] The lithium-bearing pegmatites belonging to the Kaustinen lithium province belong to the LCT group of pegmatites. They also belong to the albite-spodumene subgroup based on the pegmatites’ high spodumene and albite content (Cerny and Ercit, 2005). LCT pegmatites are very coarse-grained rocks with similar geochemical affinities to granites that are often considered the source rocks to pegmatites. LCT pegmatites are highly enriched in lithium, and tantalum, and this suite of elements gives them their name and distinguishes them from other rare caesium element pegmatites (Bradley and McCauley, 2016). They typically occur in Cainozoic to Mesoarchaean orogenic belts and have been found on most continents. They are often hosted within metasedimentary and metavolcanic rocks that are frequently metamorphosed to greenschist and amphibolite facies (Bradley and McCauley, 2016). LCT pegmatites SRK Consulting – 592138 SSW Keliber TRS Page 62 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 often show a broad geochemical zonation pattern, with pegmatites most enriched in compatible elements Li, Cs, Ta typically the furthest away from their source (granite) and represent the last phase of crystallisation (Figure 5.10). The presence of numerous granites (many being pegmatitic granites) in the Kaustinen area are thought to be the potential sources of the pegmatites, although there has been no clear or well-defined zonation observed to date to prove this. SSW Keliber Lithium Project Schematic plan view of a granite source showing evolution through to LCT pegmatite (Source: London, 2016) Project No. 592138 Figure 5.10: Schematic plan view of a granite source showing evolution through to LCT pegmatite SRK Consulting – 592138 SSW Keliber TRS Page 63 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 6 EXPLORATION [§229.601(b)(96)(iii)(B)(7) 6.1 Non-drilling activities [§229.601(b)(96)(iii)(B)(7)(i)] 6.1.1 Geological/boulder mapping Due to the paucity of outcrop through most parts of the Kaustinen region, traditional geological mapping methods have not been possible, so pegmatite exploration methodologies have primarily been restricted to boulder mapping. This form of litho-geochemical sampling and mapping has been used since the 1960s and remains an effective method to discovering hidden or buried pegmatites. Since beginning exploration work in 2010, Keliber has mapped more than 1 500 spodumene pegmatite boulders, with these boulder fans or distributions being used to identify potential pegmatite source areas. Apart from the Länttä deposit (which was discovered through a road excavation), all of the Kaustinen pegmatites were located through tracing of boulder fans to the northwest (being the regional direction of palaeo-glacial ice movement). Drilling was then focused on areas proximal to the northwest end of the boulder fan (Figure 6.1). SSW Keliber Lithium Project Spodumene pegmatite boulders and deposits (Source: Keliber) Project No. 592138 Figure 6.1: Map showing spodumene pegmatite boulders and deposits 6.1.2 Geochemical sampling During the 1970s and 1980s, GTK carried out extensive till sampling covering the entire country, including taking over 10 000 samples in the Kaustinen area (Ahtola et al., 2015). Samples were collected from an average depth of 2.4 m and along 500 – 2000 m-spaced lines, with sample intervals varying from 100 m – 400 m. Sample lines were orientated perpendicular to the direction of glacial drift (i.e., southwest – northeast). Lithium was not analysed for at the time, and only in 2010 when GTK reanalysed 9 658 samples
SRK Consulting – 592138 SSW Keliber TRS Page 64 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 from the Kaustinen area was the presence lithium confirmed. Results show broad areas of lithium anomalism that correlate well with the known/existing deposits (Figure 6.2). The results show that the till geochemistry coupled with boulder mapping can be used as an effective exploration tool in this environment. SSW Keliber Lithium Project Regional distribution of Li in till and the locations of known lithium deposits (Source: Ahtola, 2015) Project No. 592138 Figure 6.2: Regional distribution of Li in till and the locations of known lithium deposits 6.2 Drilling, logging and sampling [§229.601(b)(96)(iii)(B)(7)(ii) (v) (vi)] Apart from data generated from overburden stripping at Länttä and the exploration tunnel in Syväjärvi, diamond core drilling has been the only method used to generate geological, structural and analytical data and these have been used as the basis for Mineral Resource estimation over each of the deposits defined to date. Older drilling phases from the 1960s to early 1980s was executed by Suomen Mineraali Oy and Partek Oy targeting the Emmes, Länttä and Syväjärvi deposits. This was followed by GTK who completed drilling over the Syväjärvi and Rapasaari deposits between 2004 and 2012. Since 1999, Keliber has completed extensive drilling programmes focusing on delineating Mineral Resource estimates over each of these deposits, including the Outovesi deposit that Keliber discovered in 2010. Apart from shallow surface reverse circulation drilling completed by GTK over the Syväjärvi deposit, all drilling on the project has been completed using diamond core drilling. Historical drilling completed in the 1960s through to the 1980s was completed using 32 mm diameter drilling, with GTK drilling using a 42 mm diameter and Keliber a 50.7 mm core diameter, respectively. Most drilling was directed to intersect pegmatites at right angles to their strike, averaging 45˚ with average mean vertical drilling depth of 85 m below surface. Table 6-1 shows details of historical, GTK and Keliber drilling over each of the deposits. SRK Consulting – 592138 SSW Keliber TRS Page 65 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Table 6-1: Drilling completed over the Keliber Lithium Project Deposit Historical & GTK Keliber Total Number of drill holes Length (m) Number of drill holes Length (m) Number of drill holes Length (m) Syväjärvi 37 4 078 155 16 109 192 20 187 Rapasaari 26 3 653 263 44 482 289 48 135 Länttä 27 2 931 73 6 136 100 9 067 Emmes 84 8 891 23 2 939 107 11 830 Outovesi - - 31 2 613 31 2 613 Tuoreetsaaret - - 50 10 617 50 10 617 Leviäkangas 99 6 821 24 5 174 123 11 994 Total 273 26 374 619 88 069 892 114 443 6.2.1 Syväjärvi drilling The Syväjärvi Deposit was discovered by Suomen Mineraali Oy following boulder mapping with the first drilling being completed in 1961. This was followed by drilling by Partek Oy until the 1980s. Detailed drilling was then completed by GTK between 2006 and 2010. Following the acquisition of the project in 2012, Keliber completed several drilling campaigns between 2013 and 2019 with the focus of declaring a high- confidence Mineral Resource estimate. A total of 192 holes have been drilled over the project, totalling 20 187 m (Table 6-1 and Figure 6.3). Due to the project’s location close to Lake Syväjärvi, drilling was only possible during the winter months where access on to the lake could be achieved. Keliber’s surface drilling was completed on a broad 50 m x 50 m-spaced grid, with all drill holes having easterly azimuths in order to intersect the pegmatites as close to their true width/attitude as possible (Figure 6-3). Following completion of the exploration tunnel, an additional six underground holes were drilled along the plane of the pegmatite to test and validate its up-dip continuity. SRK Consulting – 592138 SSW Keliber TRS Page 66 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Syväjärvi – completed drilling with photo showing exploration tunnel Project No. 592138 Figure 6.3: Syväjärvi – completed drilling with photo showing exploration tunnel 6.2.2 Rapasaari drilling Following a boulder mapping, till sampling and geophysical programme, GTK discovered the Rapasaari deposit in 2009. During 2009 and 2011, GTK completed a 26-hole drilling programme, with Keliber acquiring the mineral rights to the project in 2014. Since then, Keliber completed numerous drilling campaigns, focusing on properly delineating the Rapasaari deposit geology and structure into three separate zones, two of which became the focus of Mineral Resource estimation - Rapasaari East and Rapasaari North. A total of 289 holes have been drilled over the project, totalling 48 135 m (Figure 6.4). Keliber’s surface drilling was completed on a broad 50 m x 50 m-spaced grid, with Rapasaari East drill holes having easterly azimuths and Rapasaari North drill holes having southerly azimuths in order to intersect pegmatites as close to their true width/attitude as possible. SRK Consulting – 592138 SSW Keliber TRS Page 67 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Rapasaari – completed drilling Project No. 592138 Figure 6.4: Rapasaari - completed drilling 6.2.3 Länttä drilling Following exposure of mineralised pegmatite during a road working in the 1950s, the Länttä Deposit was initially drilled by Suomen Mineraali Oy. Their work included bulk sampling and metallurgical testing in the late 1970s, but no additional work was completed as the project was considered uneconomic at the time. Keliber acquired the mineral rights to the project in 1999 and completed more detailed exploration in collaboration with GTK. In 2010, overburden stripping and exposure of both pegmatite veins was completed. Bulk samples were drawn for metallurgical test work as well as for samples to generate internal certified reference material (CRM) for the project. A total of 100 holes of diamond drill core have been drilled over the project, totalling 9 067 m. Keliber’s surface drilling was completed on broad 40 m-spaced section lines with all drill holes having north-westerly azimuths in order to intersect pegmatites as close to their true width/attitude as possible (Figure 6.5).
SRK Consulting – 592138 SSW Keliber TRS Page 68 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Länttä – completed drilling with photographs showing exposed pegmatite at surface Project No. 592138 Figure 6.5: Länttä – completed drilling with photographs showing exposed pegmatite at surface 6.2.4 Emmes drilling The Emmes deposit was discovered following boulder mapping completed by Suomen Mineraali Oy in the 1960s. Drilling by Suomen Mineraali Oy as well as Partek Oy was completed until 1981. Following acquisition of the rights in 2012, Keliber completed three drilling programs, including several ice drilling programs to validate historical holes as well as to further delineate the extent of the pegmatite beneath Lake Storträsket. A total of 107 holes of diamond drill core have been drilled over the project, totalling 11 830 m (Figure 6.6). Keliber’s surface drilling was completed using variable spacing lines with drill holes having north and north-easterly azimuths in order to intersect pegmatites as close to their true width/attitude as possible. SRK Consulting – 592138 SSW Keliber TRS Page 69 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Emmes – completed drilling Project No. 592138 Figure 6.6: Emmes – completed drilling 6.2.5 Outovesi drilling The Outovesi deposit was discovered in 2010 by Keliber, with the company completing its mineral resource inventory drilling in the same year. A total of 31 holes of diamond drill core have been drilled over the project, totalling 2 613 m (Figure 6.7). Keliber’s surface drilling was completed on broad 40 m-spaced section lines with all drill holes having easterly azimuths in order to intersect pegmatites as close to their true width/attitude as possible. SRK Consulting – 592138 SSW Keliber TRS Page 70 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Outovesi - completed drilling Project No. 592138 Figure 6.7: Outovesi – completed drilling 6.2.5.1 Tuoreetsaaret drilling The Tuoreetsaaret deposit, located between the Syväjärvi and Rapasaari deposits, was discovered in 2020 by Keliber and subsequently drilled during 2021 and 2022. The drilling is towards the east and is approximately perpendicular to the orientation of the pegmatites. As the deposit is located between the two larger orebodies, there are a large number of holes in vicinity, however only 16 of these have intersected the modelled veins. The sub-vertical veins are intersected through both east and west oriented drill holes, on approximately 40 m spaced fence lines. The veins are reasonably closely spaced, at between 10 to 50 m apart. SRK Consulting – 592138 SSW Keliber TRS Page 71 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Tuoreetsaaret – completed drilling Project No. 592138 Figure 6.8: Tuoreetsaaret – Completed Drilling 6.2.5.2 Leviäkangas drilling The Leviäkangas deposit, was discovered initially through boulder mapping, and later by percussion and diamond drilling by Partek Ab. Infill drilling was undertaken by Keliber to follow up on the more promising areas intersected by Partek Ab. The percussion drilling is not used in the Mineral Resource estimation. For the shallowest orebody at Leviäkangas the drilling is fairly closely spaced, and approximately 20 m fence lines, oriented towards the east perpendicular to the strike of the veins. For the two deeper orebodies the spacing is significantly wider at 50 to 100 m. Ove the 123 drillholes in the vicinity of the deposit (including the percussion drilling), only 24 holes, totalling 2 246 m have intersected the modelled orebodies.
SRK Consulting – 592138 SSW Keliber TRS Page 72 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Leviäkangas – completed drilling Project No. 592138 Figure 6.9: Leviäkangas – completed drilling 6.2.6 Sampling procedures All logging and sampling of diamond drill core by Keliber was completed at Keliber’s core logging and sampling facility in Kaustinen and in accordance with Keliber’s Standard Operating Procedures (SOP) that were aligned with best practice and in accordance with the JORC 2012 Code. Lithological logging criteria focused on mineralogical, lithological and structural variables, with sample intervals varying from 0.2 m to 2.5 m. Mineralogical logging focused on recording spodumene crystal size, orientation, colour, and estimated quantity. During earlier drilling phases, core was orientated by drillers (every 10 – 15 m) using the “wax stick method”. However, in later phases (post-2016), Keliber utilised a downhole digital Reflex Act III tool that measured the orientation of drill core on each three-metre run, generating more accurate results. After logging, core boxes were photographed dry and wet. All lithological, structural, mineralogical, density, Rock Quality Designation (RQD) and sampling data was captured into MS Excel® spreadsheets and then compiled into an MS Access® database. After core had been marked up for sampling, it was cut in half along the long axis using an automatic diamond saw, with half of the core being subject to drying, weighing, measurement of specific gravity (SG), further drying and then packing into sample bags for dispatch to the laboratory for preparation and analysis. 6.2.6.1 Density Keliber carried out density determinations using the water displacement (Archimedes) method and included the use of two standards that were measured at every 10th sample. A majority of Keliber’s density measurements were drawn from pegmatite material and included non-mineralised material (host rock inclusions/xenoliths). There is a strong correlation with Li2O grade (i.e., spodumene content) and density and depending on grade (usually 10 - 20 % spodumene) the density can vary between 2.65 and 2.80 g/m3. An average density of 2.70 g/m3 was therefore assumed for fresh pegmatite. This average density was SRK Consulting – 592138 SSW Keliber TRS Page 73 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 then also applied to host rock metasediments and metavolcanics due to limited density measurements being available over these domains. SRK Consulting – 592138 SSW Keliber TRS Page 74 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 7 SAMPLE PREPARATION, ANALYSES AND SECURITY [§229.601(b)(96)(iii)(B)(8)] 7.1 Sample preparation methods and quality control measures [§229.601(b)(96)(iii)(B)(8)(i)] All material used for analyses on the project was sourced from diamond drill core that was split in half using an electric diamond core saw, or a guillotine (for historical core samples). All sampling is completed at the secure core logging and sampling facility in Kaustinen. To ensure confidence in the quality of the results, precision and accuracy, Keliber have since 2013 employed a quality assurance and quality control (QA/QC) SOP over all of its drilling programs at the Keliber Project. The Quality Control (QC) policy includes the insertion of Certified Reference Material (CRM), blanks and duplicates into the sampling stream on a frequency of one in every 20 samples (5%). Duplicate QC samples included replicate samples (quarter core samples) as well as pulp duplicate samples. Keliber generated three separate in-house CRMs from samples drawn from the Länttä deposit, as well as a CRM (blank) sample drawn from the Lumppio granite (assumed to outcrop in the region). The CRMs (including the blank material) were prepared by independent laboratory Eurofin Labtium Group (Labtium) in Finland. A commercially available CRM (AMIS0355) was also used by Labtium as part of its internal QC when analysing Keliber’s samples. All sealed samples were delivered to Labtium’s independent laboratory in Kuopio, Finland who have carried out all primary sample preparation and assay for the project since 2014. 7.2 Sample preparation, assaying and laboratory procedures [§229.601(b)(96)(iii)(B)(8)(ii)] All sample preparation and analyses were completed by Labtium’s laboratory facility in Kuopio, Finland. For sample preparation, samples are weighed, dried and crushed to -6 mm, with the coarse crushed samples being split using a rotary splitter to a weight of 0.7 kg. Samples were then pulverized with an aliquot of 0.2 g being used for analyses. Pulp and coarse reject samples were retained for future analysis and possible metallurgical testing. The analytical process applied by Labtium (code 720P) is sodium peroxide fusion (700°C / 5 min) followed by dissolving in HCl plus dilution with HNO3 and analysis by ICPOES. A 27-element suite is routinely assayed using this method with a lithium detection limit of 0.001%. Check samples carried out by ALS Ltd in 2013 showed some variance between results, but this was attributable to the four-acid digest used by ALS Ltd (as opposed to a sodium peroxide fusion) being incapable of entirely dissolving silicates such as spodumene and beryl into solution. Keliber have therefore used a sodium peroxide fusion digest (Labtium code 720P) methodology for all sample analyses, as this method provides a more complete digest, and therefore more accurate analytical results. It is recommended that the residue after the fused material has been dissolved be investigated as the oxide minerals such as tantalite and columbite may not have been broken down. 7.3 Quality assurance and quality control measures [§229.601(b)(96)(iii)(B)(8)(iii)] Keliber’s QC programme included the insertion of four CRMs (including a blank) and replicate samples (comprising quarter core) with the laboratory (Labtium) completing internal QC through use of one CRM (AMIS 0355) and completing pulp duplicate analyses. 7.3.1 Replicates/duplicates Field replicates comprising quarter core samples were taken randomly for insertion in the sample stream at a ratio of 1 in 20. Results were as expected with some variance shown between the replicate pairs, but this is an expected behaviour based on the very coarse-grained and heterogenous nature of spodumene mineralisation observed throughout all of the mineralised pegmatites. This variance is also emphasised through the differing size of the sample (half core as opposed to quarter core). Pulp sample duplicates were also taken and showed little bias between the datasets (Figure 7.1). SRK Consulting – 592138 SSW Keliber TRS Page 75 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Plots of core replicate and laboratory pulp duplicate checks for Li2O from 2018 to 2020. Project No. 592138 Figure 7.1: Plots of core replicate and laboratory pulp duplicate checks for Li2O from 2018 to 2020 7.3.2 Certified reference materials The behaviour of the three in-house CRMs since 2014 has not been consistent and this has been attributable to apparent sample inhomogeneity within all three of the in-house CRMs. In nearly all cases, the mean measured lithium grades are generally lower than the certified lithium grades for all CRMs, with many analyses plotting beyond two standard deviations (Figure 7.2). The commercially available CRM used by Labtium (AMIS0355) also showed a consistent lower bias, also within the same range, but with nearly all data falling within only one standard deviation (Figure 7.3). This would suggest that grades declared by Keliber are slightly conservative (-ve ~0.05% Li2O). Despite variances between the CRM’s, the minor variances identified between them is not considered significant to the impact the quality (accuracy) of analyses generated to date. The change in the reported Li contents of the internal standards have also been observed by other Competent Persons in the past (Payne, 2022) and this may be better explained by referring to Table 7-1. Table 7-1: Reported lithium content for the three in-house standards Standards A B C Number of analyses 35 71 17 Statistic Laboratory Mean (%) Standard deviation Mean (%) Standard deviation Mean (%) Standard deviation Rovaniemi 1.02 0.04 0.73 0.03 0.60 0.05 Kuopio 1.01 0.03 0.72 0.02 0.61 0.01 Oulu 0.95 0.05 0.70 0.04 0.59 0.03 (Source: Payne (2022)) Although this change may be regarded as minor, it is more pronounced in the data reported by the Oulu Laboratory and mainly affects the Tuoreetsaaret samples submitted since 2021. This has been brought to the attention of the exploration team and recommended various remedies that are currently being investigated for implementation before a next round of Mineral Resource estimation. 7.3.3 Blanks Blanks (samples containing negligible amounts of the element of interest) are inserted into the sample stream in order to assess whether any potential contamination has been introduced during the sample preparation stages. The blank used by Keliber was also part of the same suite of in-house CRMs prepared by Labtium, and most probably also potentially suffer from some form of sample inhomogeneity. However,
SRK Consulting – 592138 SSW Keliber TRS Page 76 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 results from this CRM do not show any significant contamination throughout all batches prepared by Labtium. Blanks (samples containing negligible amounts of the element of interest) are inserted into the sample stream in order to assess whether any potential contamination has been introduced during the sample preparation stages. The blank used by Keliber was also part of the same suite of in-house CRMs prepared by Labtium, and most probably also potentially suffer from some form of sample inhomogeneity. However, results from this CRM do not show any significant contamination throughout all batches prepared by Labtium. SSW Keliber Lithium Project CRM control charts from 2018 to 2020 in analytical order. Dashed lines: certified grade means; dotted lines: ±2δ for each standard Project No. 592138 Figure 7.2: CRM control charts from 2018 to 2020 in analytical order SRK Consulting – 592138 SSW Keliber TRS Page 77 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project CRM control chart showing performance of AMIS0355 since 2016 Project No. 592138 Figure 7.3: CRM control chart showing performance of AMIS0355 since 2016 7.4 Adequacy of sample preparation, security and analytical procedures [§229.601(b)(96)(iii)(B)(8)(iv)] Keliber has been following a well-defined logging, sampling and analytical procedure since 2014. The sampling and core storage facility in Kaustinen is considered a secure facility with the sample preparation and analytical methodologies considered appropriate for the commodity being evaluated (lithium). Although CRM sample inhomogeneity is to blame for the variance in behaviour of the inhouse CRMs, the results of the external CRM (AMIS 0355) do provide some support to the integrity of the data. The resulting slightly lower or conservative grades are considered negligible (~0.05% Li) and are not considered material with respect for use in Mineral Resource estimation. The sample database is of sufficient quality and accuracy for use in Mineral Resource estimation. The QP recommends that Keliber utilises an umpire/check laboratory to analyse a subset of the previously analysed samples (~100 samples), representative of the grade range of the deposits, and to include additional commercially available CRMs as part of its QC programme in the future. 7.5 Unconventional analytical procedures [§229.601(b)(96)(iii)(B)(8)(v)] No unconventional analytical procedures have been employed by Keliber. SRK Consulting – 592138 SSW Keliber TRS Page 78 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 8 DATA VERIFICATION [§229.601(b)(96)(iii)(B)(9) 8.1 Data verification procedures applied [§229.601(b)(96)(iii)(B)(9)(i)] The following data verification exercises on the Keliber exploration data have been completed by SRK, including site visits to the project sites: • A public domain literature review including several reports (GTK) and academic studies covering the exploration history, geology and evaluation of LCT pegmatites in the Kaustinen area, many of which include references to the deposits referenced in this study; • Accessed, imported and interrogated all drill hole and geological data over each of the deposits: Syväjärvi, Rapasaari, Emmes, Länttä and Outovesi; • Completed review of Keliber’s SOPs relating to drilling, logging, sampling and QA/QC procedures; • Visually compared and verified several photographed sampled core logs with captured geology and sample data from each of the deposits; • Completed a detailed review of QC procedures carried out by Keliber; • Undertake a site visit to Keliber’s operational offices and core yard and sampling facility in Kaustinen; • A review of selected drill hole core intersections from each of the deposits with comparison to database entries and logs; • A review of core showing spodumene style of mineralisation and general pegmatite mineralogy in each of the deposits, including level of dilution/xenolith/host rock inclusion in each; • Site visits to each of the deposits, Syväjärvi, Rapasaari, Emmes, Länttä and Outovesi, and the location of the exploration tunnel at Syväjärvi and exposed pegmatite at Länttä; • Verification of a Keliber drilling collar at the Rapasaari Deposit and validating its position with the database using a handheld Garmin GPS; and • Site visit to the proposed concentrator site near Kaustinen, and the proposed chemical plant in Kokkola. 8.2 Limitations in data verification [§229.601(b)(96)(iii)(B)(9)(ii)]] There are no limitations to the data validation efforts completed to date; these have included completion of the site visit and associated validation as well as data validation and interrogation of Keliber’s data and reports. 8.3 Adequacy of data [§229.601(b)(96)(iii)(B)(9)(iii)] Since commencement of exploration in the Kaustinen region, Keliber has completed a systematic exploration and mineral resource evaluation programme that has been successful in delineating five discrete spodumene-mineralised pegmatite deposits. The work completed to date has captured all the important variables (mineralogical, structural, lithological) required to properly define the attitude of the host pegmatite/s and importantly, the spodumene or grade distribution within the various pegmatites that host each deposit. The exploration data that has been captured to date (consisting primarily of drilling data) is of suitable quality to be used in Mineral Resource estimation and for the purposes used in this TRS. SRK Consulting – 592138 SSW Keliber TRS Page 79 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 9 METALLURGICAL TESTING AND MINERAL PROCESSING [§229.601(b)(96)(iii)(B)(10)] The first metallurgical tests were completed in the early 1970s by Paraisten Kalkkivuori Oy. Keliber began studying the deposits in 1999 and between 2001 and 2006, in partnership with Outotec, developed a new lithium carbonate production process. More intensive investigations started in 2014. In June 2018 Keliber completed a DFS for a project to produce battery-grade lithium carbonate from spodumene-rich pegmatite deposits in Central Ostrobothnia, Finland. However, following further market studies it was decided to consider the production of battery-grade lithium hydroxide monohydrate (LiOH·H2O), or more simply lithium hydroxide (LiOH) instead of lithium carbonate. A series of tests was completed to determine the production parameters of lithium hydroxide from spodumene ore. Engineering studies were undertaken to produce 12 500 tpa of battery-grade lithium hydroxide via the following unit processes: • Concentration comprising crushing, optical sorting, grinding and flotation to produce a spodumene concentrate; • Conversion of the spodumene concentrate from alpha to beta-spodumene by roasting in rotary kiln; and • Soda leaching in an autoclave and hydrometallurgical processing including solution purification, crystallisation and dewatering to produce lithium hydroxide. In January 2022, Keliber issued a draft DFS (WSP Global Inc., 2022c) based on the production of 15 000 tpa of battery-grade lithium hydroxide. A Definitive Feasibility Study was issued on 1st February 2022. 9.1 Metallurgical Testing 9.1.1 Historical metallurgical test work After the initial metallurgical tests conducted in the early 1970s, further investigation was undertaken between 1976 and 1982. Research included mineral processing tests to produce spodumene concentrate as well as its by-products: quartz, feldspar and mica concentrates. Keliber restarted metallurgical testing in 2003, which led to the preliminary engineering for a spodumene concentrator and a lithium carbonate production plant. Mineral processing included two-stage grinding, gravity separation, de-sliming, pre-flotation, spodumene flotation and dewatering. Conversion from alpha to beta-spodumene was undertaken in a rotary kiln and the hydrometallurgical process included pressure leaching of beta-spodumene in a soda environment, solution purification with ion exchange, and precipitation of lithium carbonate. Subsequent changes to the process route have principally been in the production of lithium hydroxide. 9.1.2 Recent mineral processing test work The purpose of the mineral processing circuit is to produce spodumene concentrate for the downstream pyrometallurgical and hydrometallurgical processes. Typically, commercial spodumene concentrate would target a grade of 6% Li2O. However, given that concentrate transportation costs to the relatively close KIP are low, the concentrate grade will be a point of optimisation. During the production phase the concentrate grade will be optimized depending on the grade-recovery relationship and price of the end product. Generally speaking, the production of lower grade concentrate will be more feasible at high product price. The level of impurities in the concentrate is also important. Keliber test work programmes have revealed iron, arsenic and phosphate to be the main impurities in the spodumene flotation concentrate that impact on the downstream process. The maximum levels have been indicated at 2% for Fe2O3, 50 ppm for As and 0.4% for P2O5. 9.1.2.1 Länttä pilot test in 2015 In the 2015 PFS, samples of Länttä ore were tested at pilot-scale. Representivity of test samples [§229.601(b)(96)(iii)(B)(10)(ii)]
SRK Consulting – 592138 SSW Keliber TRS Page 80 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Three samples with a total mass of 14.8 t and combined grade of 1.27% Li2O, 0.0092% Nb and 0.0024% Ta, were processed through a pilot plant. The 2022 DFS Report referenced the primary sample but not did not describe the sampling details. Testing laboratory and certification [§229.601(b)(96)(iii)(B)(10)(iii)] The combined sample of Länttä ore was treated through a pilot mineral processing plant at the mineral processing and materials research unit (Mintec) of the GTK in Outokumpu, Finland. The spodumene concentrates produced were then processed by conversion and hydrometallurgical testing. This is described in sub-section 9.1.3: Laboratory-scale conversion tests. GTK’s quality system consists of the following elements: • GTK’s quality manual; • Standard operating procedures; and • Appendices and reference material The ISO 9001 2015 quality system standard is applied in all production-related activities, such as mapping and measuring, and the mineral technology laboratory’s research and process operations, among others. The quality system describes the flow of GTK’s processes so that everything related to customer service, the reliability and efficiency of operations, and environmental protection is defined to meet the requirements of the standard. Mineral processing testing and results The pilot plant included dense media separation (DMS), rod milling with gravity separation and flotation. Sample preparation for the pilot plant test included crushing and screening into two fractions, 0-3 mm and 3-6 mm. DMS was executed separately for these size fractions. Fines were fed directly to the spodumene flotation circuit with a feed rate of 300 kg/h. Unfortunately, the pilot plant de-sliming cyclones were ineffective, resulting in sub-optimal flotation. Laboratory scale flotation tests were accordingly used to complement the pilot plant results. It was shown that the combination of DMS and flotation resulted in 2% to 3% increase in lithium recovery compared with simple flotation. Test results obtained from combined DMS, and flotation indicated a recovery of 85.9% with a 4.59% Li2O in the spodumene concentrate. 9.1.2.2 Syväjärvi laboratory tests in 2015 Representivity of test samples [§229.601(b)(96)(iii)(B)(10)(ii)] Laboratory scale tests were carried out on Syväjärvi sample collected from drill cores with an average grade of 1.47% Li2O. Primary sampling details were not described in the 2022 DFS Report. Testing laboratory and certification [§229.601(b)(96)(iii)(B)(10)(iii)] The draft 2022 DFS does not state where these tests were conducted but presumably, they were conducted at the GTK Mintec facility. The spodumene concentrates produced were then processed by conversion and hydrometallurgical testing. This is described in sub-section 9.1.3: Laboratory-scale conversion tests. GTK certification details are provided in sub-section 9.1.2 ‘Länttä pilot test in 2015. Mineral processing testing and results Laboratory scale test work included DMS and flotation with the purpose to compare the metallurgical performance of Syväjärvi ore with the Länttä ore tested earlier in pilot-scale. In addition, a concentrate was produced for subsequent leaching tests. SRK Consulting – 592138 SSW Keliber TRS Page 81 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Tests confirmed that Syväjärvi ore can be processed using a similar flowsheet to Länttä. Recoveries for a concentrate of 4.5% Li2O were higher than achieved with the Länttä sample: 90.0% when only flotation was applied and 93.5% when both DMS and flotation were used. Phosphorus content of the produced spodumene concentrate was higher in the DMS and flotation alternative: 0.59% P2O5 compared with 0.26% when only flotation was applied. 9.1.2.3 Syväjärvi pilot tests in 2016-2017 (PFS) Representivity of test samples [§229.601(b)(96)(iii)(B)(10)(ii)] For the PFS, a tunnel was mined during the summer of 2016 to extract a bulk sample for pilot plant and other testing. Four breaks were mined from pure spodumene pegmatite at the end of the tunnel, which were separately stockpiled (Figure 9.1). The 160 t bulk sample of Syväjärvi ore had a grade of 1.445% Li2O. A waste rock sample containing 0.188% Li2O was also collected as dilution in mineral processing tests. SRK Consulting – 592138 SSW Keliber TRS Page 82 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Spodumene pegmatite at the end of the tunnel (top) and numbered ore piles before transport to GTK Mintek (bottom) Project No. 581648 Figure 9.1: Spodumene pegmatite at the end of the tunnel and numbered ore piles before transport to GTK Mintek A plan and long section showing the location of the tunnel relative to the Syväjärvi deposit are shown in Figure 9.2. SRK Consulting – 592138 SSW Keliber TRS Page 83 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Syväjärvi pilot sample location plan view (top) and long section view (bottom) Project No. 592138 Figure 9.2: Syväjärvi pilot sample location – plan and long section views Testing laboratory and certification [§229.601(b)(96)(iii)(B)(10)(iii)] An ore sorting test programme was completed in the TOMRA sorting test facility in Wedel, Germany. Mineral processing tests were conducted at pilot-scale at the GTK Mintec facility in Outokumpu. The spodumene concentrates produced were further used in laboratory and pilot conversion tests, with the converted concentrate then used in both laboratory and pilot-scale leaching tests. This is described in this
SRK Consulting – 592138 SSW Keliber TRS Page 84 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 report sub-section 9.1.2 Länttä pilot test in 2015. It was noted that the full Keliber process was thus tested at pilot-scale. TOMRA is certified to the ISO 9001 and ISO 14001 quality system standards. GTK certification details are provided in sub-section 9.1.2 Länttä pilot test in 2015. Optical sorting testing and results Sorting tests were conducted using 4 t of Syväjärvi run-of-mine (RoM) spodumene-rich ore (20 to100 mm in size) and 500 kg of black waste rock. The focus of the tests was to remove black plagioclase porphyrite waste rock from the plant feed. TOMRA’s test set-up included a PRO secondary COLOR NIR, which consists of a colour line scan CCD camera and a near-infrared (NIR) scanner. The combination of these sensors takes advantage of the absorption fingerprint of minerals in the NIR wavelength range and the colour characteristics. Ore sorting was found to be effective in removing black waste rock from the ore feed at different artificial waste rock sorter feed compositions. The sorting results indicate around 12% of the mass and 3% of the Li2O was lost in sorting. After accounting for the 0 - 20 mm fine fraction that will bypass sorting, there was a mass rejection of 10.1% with 2.2% lithium losses. In 2018, complementary batch-scale tests were carried out on hand-picked samples from Syväjärvi, Länttä and Rapasaari. In addition to the main aim of verifying the separation of the pegmatite ore from the dark country rock, tests were conducted to separate spodumene pegmatite from barren pegmatite. The separation of black country rocks from pegmatite (ore-bearing and barren) was achieved with the COLOR, NIR and XRT sensor. It was noted that the LASER sensor could also be used to separate the spodumene- bearing ore from the barren pegmatite but that further testing at pilot-scale would be needed to verify the mass balance and possible lithium losses. Mineral processing testing and results Pilot plant tests using rod and ball mills operating in closed circuit, gravity concentration and flotation were conducted in September 2016 at the GTK Mintec facility in Outokumpu. The pilot-scale processing was divided into two campaigns, with the first processing of 71 t of material with a 10% waste (country rock) dilution and the second 73 t with a 3% dilution. The flowsheet was based on Länttä pilot plant test but without DMS due to high P2O5 concentrations seen previously in Syväjärvi concentrate. The following key unit processes were included: • Crushing; • Grinding and classification; • Gravity concentration; • De-sliming; • Pre-float flotation; • Magnetic separation; and • Flotation. Results showed two subsets, with one averaging 75% recovery at 5.3% Li2O and the other averaging 82% recovery at 4.7% Li2O. Based on the GTK report, the biggest lithium losses were in the primary de-sliming and the spodumene rougher tails, totalling 9 to10%. Abrasion and crushing work indices were determined by Sandvik at its test centre in Svedala using Syväjärvi ore and waste rock samples from the pilot feed material as summarised in Table 9-1. SRK Consulting – 592138 SSW Keliber TRS Page 85 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Table 9-1: Syväjärvi comminution characteristics Material Type Measurement Comment Abrasion Index Syväjärvi ore 0.40 Abrasive Syväjärvi waste rock 0.27 Abrasive Crusher Work Index Syväjärvi ore 12.4 ± 1.9 Soft Syväjärvi waste rock 13.9 ± 1.8 Medium hard Rod Mill Work Index Syväjärvi ore 15.3 Hard Syväjärvi waste rock 16.7 Hard Ball Mill Work Index Syväjärvi ore 18.9 Hard Syväjärvi waste rock 12.6 Medium 9.1.2.4 Laboratory flotation tests for Länttä and Syväjärvi in 2016 Representivity of test samples [§229.601(b)(96)(iii)(B)(10)(ii)] More than 50 bench-scale, batch flotation tests were carried out in this phase of investigation. The programme included the following sample materials: • Länttä deep ore drill core sample; • Syväjärvi drill core sample; • Outotec (TOMRA) sorting test work samples; • Cyclone overflow from Syväjärvi pilot plant test work 2016; • Slimes from Syväjärvi pilot plant test work 2016; and • Upgraded, Syväjärvi pilot concentrate sample. The Länttä drill core sample was collected from three drill cores in the central part of the deposit. The samples were from depth levels of between 20 m and 40 m and visible weathering was not observed from the drill cores. The waste rock was excluded from the batch float sample. The Syväjärvi drill core sample was collected from one drill core. The sample contained only spodumene pegmatites and waste rock was excluded from the sample. The sample was taken well below the surface to compare the effect of weathering with the Syväjärvi pilot processing sample. Testing laboratory and certification [§229.601(b)(96)(iii)(B)(10)(iii)] The batch flotation tests were carried out at the GTK Mintec facility in Outokumpu. The concentrate was also upgraded for subsequent testing for spodumene conversion. GTK certification details are provided in sub-section 9.1.2 Länttä pilot test in 2015. Mineral processing testing and results The focus of the programme was to optimise flotation conditions with the Syväjärvi and Länttä ore samples. The concentrate was also upgraded for subsequent testing for spodumene conversion. Average flotation results are shown in Table 9-2. SRK Consulting – 592138 SSW Keliber TRS Page 86 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Table 9-2: Summary flotation results Feed Test Product Grade (%Li2O) Recovery (% Li) Syväjärvi Drill core - 3.35 mm 40 Rougher Conc 3.36 95.9 Cleaner Conc 7 6.15 85.9 Calculated Feed 1.46 100 Länttä Drill core -3.35 mm 7 Rougher Conc 2.01 90.9 Cleaner Conc 7 5.59 82.0 Calculated Feed 1.20 100 Syväjärvi Pilot run cyclone O/F 3% wt. 29 Rougher Conc 3.22 90.9 Cleaner Conc 7 6.29 77.2 Calculated Feed 1.36 100 Syväjärvi SPG 7&8 TOMRA 1 Rougher Conc 3.37 92 Cleaner Conc 7 6.00 87.7 Calculated Feed 1.59 100 It was noted that optimisation of the flotation conditions was generally successful. 9.1.2.5 Geo-metallurgical study in 2016 - 2017 Representivity of test samples [§229.601(b)(96)(iii)(B)(10)(ii)] Sampling was designed by Keliber’s Chief Geologist and a total of 18 ore samples were collected from the Syväjärvi, Länttä and Rapasaari deposits. Testing laboratory and certification [§229.601(b)(96)(iii)(B)(10)(iii)] The geo-metallurgical tests were carried out at the GTK Mintec facility in Outokumpu. GTK certification details are provided in sub-section 9.1.2 ‘Länttä pilot test in 2015.’ Geo-metallurgical testing and results The study included modal analysis by Mineral Liberation Analysis, chemical composition of spodumene by Energy Dispersive Spectroscopy, grindability tests and diagnostic flotation tests. The flowsheet and the conditions in the diagnostic test were similar to the test developed for the Syväjärvi ore. The following properties relevant to processing were considered: lithium grade; spodumene grain size; alteration; and wall rock type and dilution percentage. Grindability was seen to correlate with spodumene grade in that the higher the grade, the greater the resistance to being ground. No significant difference was observed between deposits. In all the ores, the flotation performance was strongly dependent upon the spodumene head-grade and wall rock dilution. The recovery of lithium at concentrate grade of 4.5% Li2O, increased with the lithium head-grade as shown in Figure 9.3. The wall rock dilution impacted negatively on the flotation performance. SRK Consulting – 592138 SSW Keliber TRS Page 87 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Lithium recovery as a function of feed grade (Source: Keliber 2019 and 2021 DFS Reports) Project No. 592138 Figure 9.3: Lithium recovery as a function of feed grade The diagnostic flotation tests showed a significant difference between deposits, with Syväjärvi showing the best performance followed by Länttä and Rapasaari, as seen in Figure 9.4. Individual flowsheet, processing conditions and optimisation will therefore be needed for each ore to maximise the metallurgical performance.
SRK Consulting – 592138 SSW Keliber TRS Page 88 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Lithium recovery as a function of concentrate grade (Source: Keliber 2019 and 2021 DFS Reports) Project No. 592138 Figure 9.4: Lithium recovery as a function of concentrate grade 9.1.2.6 Laboratory flotation tests for Rapasaari in 2017 Exploration and resource drilling of Rapasaari during 2016 and 2017, led to the deposit becoming the biggest ore body of the Keliber Lithium Project. Mineral processing testing was, however, quite limited and therefore further testing of Rapasaari was started in July 2017. Mineral processing testing and results With the new sample and after optimisation, Rapasaari lithium recovery was reported to be close to that achieved for Syväjärvi. 9.1.2.7 Rapasaari locked-cycle flotation test work 2018 (DFS) Representivity of test samples [§229.601(b)(96)(iii)(B)(10)(ii)] The programme was executed with the following Rapasaari sample materials: • Average ore around 100 kg; • High grade ore around 87 kg; and • Waste rock around 40 kg. The 2022 DFS report did not describe drill core sampling details. Testing laboratory and certification [§229.601(b)(96)(iii)(B)(10)(iii)] The Rapasaari flotation tests were carried out at the GTK Mintec facility in Outokumpu. GTK certification details are provided in sub-section 9.1.2.1. Mineral processing testing and results The programme included 16 batch flotation tests to optimise flotation conditions and a locked-cycle flotation test. Mineral liberation analysis was utilised to characterise the average ore, waste rock and final SRK Consulting – 592138 SSW Keliber TRS Page 89 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 flotation concentrate mineralogical properties. The results of batch flotation tests indicated that coarser grinding had a positive effect upon flotation. Higher waste rock dilution decreased the final concentrate grades and recoveries. Lower collector dosage in the pre-flotation resulted in higher Li2O recovery in the spodumene flotation but slightly higher magnesium grade in the final concentrate. In the locked cycle test, the required collector dosage was found to be about 20% of that needed in the open circuit. The locked-cycle grade-recovery points showed about 1% higher lithium recovery than the corresponding grade in open circuit. The final concentrate grade for the last five rounds (average) was 4.34% Li2O at 88.36% lithium recovery. 9.1.2.8 Emmes laboratory-scale flotation tests and further optimisation tests 2018 Representivity of test samples [§229.601(b)(96)(iii)(B)(10)(ii)] The 2022 DFS report noted that, as Emmes ore had yet to be tested by Keliber, a representative sample was collected in 2018. Primary sampling details were not described. The Emmes ore sample had grades of 1.43% Li2O and the wall rock mica schist 0.265% Li2O. In chemical and modal composition, both the ore and wall rock were reportedly typical for spodumene pegmatite deposits of Central Ostrobothnia. Spodumene was the main lithium mineral but traces of cookeite and siclerite were also detected. Testing laboratory and certification [§229.601(b)(96)(iii)(B)(10)(iii)] The 2022 DFS report does not state where these tests were conducted but presumably, they were conducted at the GTK Mintec facility. GTK certification details are provided in sub-section 9.1.2.1. Mineral processing testing and results The Emmes ore showed a similar flotation response to Syväjärvi. The lithium recovery at 4.5% concentrate grade was 91.8% and 91.0% at 5.0% grade. Wall rock dilution resulted in an almost linear decrease in the final concentrate grade: e.g., the final concentrate was 5.8% for the sample with no dilution and 5.0% with 10% dilution. With a fixed concentrate grade, the dilution caused a decrease in recovery, but this was significantly lower for Emmes than Syväjärvi: e.g., when wall rock dilution was increased from zero to 10%, Syväjärvi recovery at 4.5% Li2O decreased from 92.2% to 85.8%, whereas only 0.6% loss to 91.2% was experienced for Emmes. 9.1.2.9 Flotation tests for Rapasaari and Outovesi 2019 Representivity of test samples [§229.601(b)(96)(iii)(B)(10)(ii)] This programme was initiated in November 2018 and includes ore variability tests on different Rapasaari ore types, initial flotation tests on Outovesi and a locked-cycle test on a Rapasaari drill core sample. The programme was conducted with the following Rapasaari and Outovesi sample materials: • Average ore 56 kg; • High grade ore around 8 kg; • Waste rock around 35 kg; • Rapasaari North ore 38 kg; • Rapasaari West 86 kg; • Rapasaari South-West 86 kg; • Outovesi ore 64 kg; and • Outovesi white and black waste rock total 26 kg. SRK Consulting – 592138 SSW Keliber TRS Page 90 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Primary sampling details were not described in the 2022 DFS report. Testing laboratory and certification [§229.601(b)(96)(iii)(B)(10)(iii)] This programme was initiated in November 2018 and completed in April 2019 at the GTK Mintec facility. GTK certification details are provided in sub-section 9.1.2.1. Mineral processing testing and results Modal mineralogy determined that the spodumene content in Rapasaari samples varied from 13.1% to 20.6%. Small contents of some other lithium-containing minerals were also found, including petalite, trilithionite and triphylite. The primary gangue minerals were plagioclase (25.7 – 36%) and quartz (26.9 – 31%). Other gangue minerals were microcline, K-feldspar and muscovite. The Bond rod mill work index value was found to be 15.3 kWh/t and ball mill work index15.2 kWh/t. In terms of the JKTech scale, the Rapasaari West sample would be classified as a hard material. Regarding the spatial variability, the best Li2O grades and recoveries were achieved from the Rapasaari North sample and the results from the Rapasaari West sample were quite similar. The recoveries were a bit lower from the Rapasaari Main sample. The poorest results were achieved from Rapasaari South-West as shown in Figure 9.5. SSW Keliber Lithium Project Variability in Rapasaari flotation recovery (source: Keliber 2021 DFS) Project No. 592138 Figure 9.5: Variability in Rapasaari flotation recovery The flotation behaviour of Outovesi mineralised samples were rather similar to Rapasaari Main and Ra- all-2019 composite, as shown in Figure 9.6. SRK Consulting – 592138 SSW Keliber TRS Page 91 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Variability in Outovesi flotation recovery (Source: Keliber 2021 DFS) Project No. 592138 Figure 9.6: Variability in Outovesi flotation recovery Overall, the higher the waste rock dilution ratio the lower the Li2O grades and recoveries in the cleanings, regardless of the sample. Based on the results, it seems clear that the head grade will have an effect on Li2O recoveries. This was confirmed partially by spatial variability testing where the Rapasaari North was found to have the best flotation response and the highest head grade. The grades and the recoveries in the locked-cycle flotation test with the Ra-all-2019 composite were lower in comparison to the single batch flotation test with the same material. Flotation without desliming produced good results, as did magnetic separation on the final spodumene concentrate. The normal slurry density of 30% in the conditioning of the pre-flotation stage seemed to work quite well. It was noted in the 2022 DFS report that such process changes should be considered for future studies and process design. 9.1.2.10 Optical ore sorting in 2018 Representivity of test samples [§229.601(b)(96)(iii)(B)(10)(ii)] Sorting tests were conducted in November 2018 using Syväjärvi RoM ore (4 to 35 mm in size) spodumene- rich material and black waste rock. Syväjärvi ore samples included spodumene-pegmatite ore (grey-green) and reddish marginal ore (red, light) including muscovite pegmatite and potassium feldspar. Syväjärvi dark side rock sample includes plagioclase-porphyrite and mica schist. Feed sample for the sorting tests included the Syväjärvi ore and marginal ore in ratio 1:10 with 15% of side rock dilution. Primary sampling details were not described in the 2022 DFS report. Testing laboratory and certification [§229.601(b)(96)(iii)(B)(10)(iii)] The sample was crushed and screened at GTK Mintec before dispatch to Binder+Co sorting test facility in Gleisdorf, Austria. AAS and XRF analyses were conducted at Labtium – Eurofins laboratories from the subsamples for each ore types and side rock. The Certification Body of TÜV SÜD Management Service GmbH certified that Binder GmbH has established and applies a Quality Management System according to ISO 9001:2015.
SRK Consulting – 592138 SSW Keliber TRS Page 92 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Mineral processing testing and results The focus of the tests was to remove black plagioclase porphyrite waste rock from the plant feed. Size classes 12/20 and 20/35 mm were washed at a rinsing feeder before the optical sorting. Additional sorting of smaller 4/12 mm size class was sorted without washing; instead, air knives and dust removal were utilised. Ore sorting was found effective in removing black waste rock from the artificial composite ore feed. The lithium grade of the reject in the tests was 0.2-0.3% Li2O. Lithium content of the black waste rock in contact with the ore varied between 0.08 and 0.47% Li2O with the average being in the range 0.24 - 0.30% Li2O. It was reported that lithium in country rocks was not included in the Mineral Resources nor in Mineral Reserves. Thus, the recovery of lithium carried by pegmatite was practically 100% in the test work. 9.1.2.11 Optical ore sorting at Redwave in 2019 Representivity of test samples [§229.601(b)(96)(iii)(B)(10)(ii)] Sorting tests were conducted in August 2019 using samples of Syväjärvi spodumene-rich material and black waste rock (12.4 to 20 mm in size). The focus of the tests was to remove black plagioclase porphyrite waste rock from the plant feed. Testing laboratory and certification [§229.601(b)(96)(iii)(B)(10)(iii)] An ore sorting test programme was completed in the Redwave sorting test facility in Eggersdorf, Austria. The Certification Body of TÜV SÜD Management Service GmbH certified that Redwave, a division of BT- Wolfgang Binder GmbH, has established and applies a Quality Management System according to SCC**:2011. Mineral processing testing and results The sample was crushed and screened at GTK Mintec before dispatch to Binder for optical sorting testing that is described in sub-section 9.1.2.1. After completing the test work at Binder, the same sample was delivered to Redwave to complete the same test work procedure to support the best sorting equipment selection. Redwave only uses a double-sided Red Green Blue camera as a sensor. The equipment was reported to be robust and suitable for the mining environment. Unfortunately, laboratory assay results were not available to support the results. More test work including assaying of the products and optimisation of the operating parameters was recommended. 9.1.2.12 Syväjärvi pilot testing in 2019 (DFS) Representivity of test samples [§229.601(b)(96)(iii)(B)(10)(ii)] This pilot campaign processed 89 t of the Syväjärvi ore at a waste rock dilution of 4%, being the dilution as modelled in the LoM plan of that time. The feed material was the same as that used in the 2016 pilot campaign discussed in sub-section 9.1.2.1. Testing laboratory and certification [§229.601(b)(96)(iii)(B)(10)(iii)] This programme was conducted at the GTK Mintec facility in August 2019. GTK certification details are provided in sub-section 9.1.2.1. Mineral processing testing and results Pilot tests conducted are shown in Figure 9.7. The minerals processing flowsheet included grinding, desliming, pre-float, spodumene flotation and low intensity magnetic separation. SRK Consulting – 592138 SSW Keliber TRS Page 93 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Overall spodumene recovery was increased by 4% from the previous Syväjärvi pilot, to 88%. The recovery increase was achieved by reducing the slime production, optimisation of the pre-float and high intensity conditioning condition and increasing the residence times in spodumene flotation. SSW Keliber Lithium Project Syväjärvi pilot tests 2019 Project No. 592138 Figure 9.7: Syväjärvi pilot tests 2019 9.1.2.13 Dewatering studies on Syväjärvi pilot processing samples by Outotec in 2019 (DFS) Representivity of test samples [§229.601(b)(96)(iii)(B)(10)(ii)] Samples were extracted from the Sy-väjärvi pilot circuit. Testing laboratory and certification [§229.601(b)(96)(iii)(B)(10)(iii)] Outotec representatives were present several days at GTK Mintec during the Syväjärvi pilot processing in August 2019. Outotec performed dewatering tests of the spodumene concentrate at the Outotec dewatering technology centre in Lappeenranta, Finland. Thickening tests were performed at the Outotec Research Centre in Pori, Finland. Metso Outotec complies with the requirements of international standards for management systems. The majority of Metso Outotec’s major units are certified to ISO 9001 (quality), and the main operational units also have ISO 14001 (environment), ISO 45001 or OHSAS18001 (safety) standards as a framework. Ore 89 t @ 1.32% Li2O Side rock dilution ˜ 4% Spodumene concentrate ˜ 2.9 t ˜ 4.5% Li2O (alpha spodumene) Calcined concentrate ˜ 2 t ˜ 4.5% Li2O (beta spodumene) Baterry grade LiOH.H2O FLSmidth 2019 Continuous conversion pilot Outotec Finland 2019 Continuous LiOH production pilot Syväjärvi test mining 2016 Ore and waste rock GTK Mintec 2019 Mineral processing pilot SRK Consulting – 592138 SSW Keliber TRS Page 94 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Mineral processing testing and results Filtration tests of spodumene concentrate The main objective was to determine moisture content of the cake, confirm filter cloth selection and maximum filtration capacity for vacuum belt and vertical pressure filters. A final moisture content of 9.6% was achieved with the vacuum belt filter and 7.3% was achieved with the vertical pressure filter. Both values are below the moisture limit of 10% for the final concentrate before the hot conversion at the Keliber Lithium Hydroxide Refinery. Thickening tests Test work of the pre-float, spodumene flotation feed, tailings, tailings without slime, slime and spodumene concentrate showed that the materials can be thickened successfully. Keliber wanted to test settling of flotation tailing with and without slime to inform decision making on the tailing’s storage designs. Filtration tests of flotation tailings Filtration of the flotation tailings was a continuation of the thickening tests. Keliber wanted to complete testing to support engineering for potential dry stacking of the flotation tailings. Tailings with slime could be dewatered successfully by an Outotec vacuum belt filter (20.6%), filter press filtration (12.1%) and fast opening filter press filtration (13.3%). Tailings without slime was found difficult to filter with coarser PSD. The following results were achieved: Outotec vacuum belt filter (18.9%) and fast opening filter press filtration (13.9%). 9.1.2.14 Dewatering study of the spodumene concentrate by Metso Minerals in 2019 Representivity of test samples [§229.601(b)(96)(iii)(B)(10)(ii)] Samples were extracted from the Syväjärvi pilot circuit. One barrel containing a 50 kg sample of concentrate was delivered to the Metso Minerals laboratory in Sala. Testing laboratory and certification [§229.601(b)(96)(iii)(B)(10)(iii)] During the Syväjärvi pilot processing campaign in 2019 representatives from Metso Minerals visited to witness the pilot plant operation. Metso Minerals proposed vendor test work to support spodumene concentrate filter selection and sizing data. Details of the Metso Outotec certification are provided in sub-section 9.1.2.1. Mineral processing testing and results After thickening and top feed vacuum filtration, the end moisture of the concentrate was measured to be in the range of 10 – 13%. 9.1.2.15 XRT ore sorting tests at Outotec (TOMRA) in 2019 Representivity of test samples [§229.601(b)(96)(iii)(B)(10)(ii)] Sorting testing at TOMRA was a continuation of testing described in earlier sections with the same ore and waste rock samples. Testing laboratory and certification [§229.601(b)(96)(iii)(B)(10)(iii)] Sorting tests were conducted at Outotec (TOMRA). TOMRA is certified to the ISO 9001 and ISO 14001 quality system standards. Mineral processing testing and results The purpose of this test work was to determine the suitability of a TOMRA® sorting system for the Syväjärvi operation. The tested samples were represented in two size fractions: +12.4 - 20 mm and +20 – 35 mm. Before the test, the samples were mixed in a ratio of 79.1% product; 7.9% marginal ore and 13% waste. SRK Consulting – 592138 SSW Keliber TRS Page 95 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Results showed high lithium recovery of approximately 95% for both size fractions, with mass rejection of 16 to 19%. The results showed positive amenability of TOMRA XRT ore sorting technology with Syväjärvi material. Further testing and engineering were however, recommended for the final flowsheet development of the crushing and sorting circuit. 9.1.2.16 Rapasaari laboratory-scale programme to control sulphides at GTK in 2021 Representivity of test samples [§229.601(b)(96)(iii)(B)(10)(ii)] In total, 80 kg of pegmatite ore sample from the Rapasaari deposit was collected from rejects of analytical samples of half-cut drill cores. The 50 kg feed sample for the bench-scale beneficiation tests comprised 47.5 kg Rapasaari ore and 2.5 kg waste rock. After homogenisation, the feed material was divided into suitable 1 kg and 5 kg sub-samples for the test work. In February 2021 approximately 30 kg additional Rapasaari ore and 3 kg of Rapasaari waste rock were packed and sent to SGS Canada for parallel test work purposes (sub-section 9.1.2.17). Testing laboratory and certification [§229.601(b)(96)(iii)(B)(10)(iii)] This programme was conducted at the GTK Mintec facility. GTK certification details are provided in sub-section 9.1.2.1. Mineral processing testing and results Keliber contracted GTK Mintec to study processing alternatives to manage arsenic levels of the final concentrate and develop the process, at bench-scale, for overall arsenic management. The programme included sample preparation, flotation tests, magnetic separation and gravity separation tests. The arsenopyrite occurred mainly in the waste rock bulk sample, where its content was 0.09%. In addition, the arsenopyrite particles were totally liberated in the ground Rapasaari composite sample. The average Li2O grade in the Rapasaari composite sample was 1.23% and arsenic 0.021%, calculated from the bench- scale tests. The grain sizes (P80) of spodumene and arsenopyrite were 90 µm and 24 µm in the ground (125 µm) feed samples, respectively. In total, more than 20 bench-scale flotation tests were performed, with combinations of different unit processes to remove arsenopyrite. High gradient magnetic separation was shown to not be an effective method of removing arsenopyrite. Gravity separation by shaking table worked well; however, several cleanings were required in order to avoid spodumene losses. About 50 – 70% of arsenic could be removed by pre-flotation. Sulphide flotation without pre-flotation and NaOH conditioning had a negative effect regarding selectivity in spodumene flotation. The programme proved that most arsenopyrite could be removed by sulphide flotation. The process was shown to be very sensitive regarding spodumene flotation and it was reported that fresh water should be used in all stages. It was noted further that it is essential to remove more than 95% of arsenic prior to spodumene flotation, because the arsenopyrite tends to enrich during the spodumene flotation. 9.1.2.17 Rapasaari laboratory-scale programme to control sulphides at SGS in 2021 Representivity of test samples [§229.601(b)(96)(iii)(B)(10)(ii)] SGS Minerals was provided with the same sample material as used in the programs at GTK Mintec (GTK certification details are provided in sub-section 9.1.2.1. Testing laboratory and certification [§229.601(b)(96)(iii)(B)(10)(iii)] Keliber sought a second test work programme and new ideas for the Rapasaari ore flowsheet development in early 2021, especially for the arsenic and sulphur management. This programme was conducted at SGS Minerals.
SRK Consulting – 592138 SSW Keliber TRS Page 96 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SGS Minerals is accredited to the requirements of ISO/IEC 17025 for specific tests listed on their scope of accreditation, including geochemical, mineralogical and trade mineral tests. Mineral processing testing and results The main objective of the metallurgical test work was to develop an appropriate flowsheet for producing a high-grade spodumene concentrate, with a reasonable recovery, from a composite sample from the Rapasaari deposit. Rejecting arsenic and sulphur content was also a focus. Test work on the composite sample included head characterisation, mineralogical examination, heavy liquid separation, magnetic separation, and flotation. The lithium grade in the composite sample was 1.18% Li2O. The iron content after 5% waste rock dilution was low, at 0.77% Fe2O3. The sample was radioactive-free, with <0.01% Ta2O5. The grades of arsenic and sulphur in the sample were 0.03% and 0.04%, respectively. Heavy liquid separation (HLS) was completed on the Rapasaari ore sample to evaluate the potential of gravity separation. It was concluded that the Rapasaari ore is not amenable to DMS separation. Wet high-intensity magnetic separation (WHIMS) tests effectively rejected iron-bearing gangues (possibly pyrite, pyrrhotite, and arsenopyrite, iron silicate minerals) from the 100% passing 48 mesh (300 µm) feed. WHIMS at 5 000 Gauss rejected ~20% Fe2O3, 8% As and 29% S, with only 2.4% of the lithium deporting to the magnetic products. Further optimisation on the magnetic separation tests was recommended to reject more iron-bearing gangues with relatively less lithium loss. Seven flotation tests were carried out after grinding to 100% pass 48 mesh (300 µm). Spodumene upgrading was achieved in a flowsheet that comprised one rougher stage and three cleaner flotation stages. The lithium concentrates produced achieved grades of 5.4 ~ 5.8% Li2O at 84 ~ 92% lithium recoveries. The Fe2O3 and arsenic assays of the flotation concentrate were <1% and <0.005%, respectively, after passing the spodumene concentrate thorough WHIMS. A final stage of WHIMS on the spodumene concentrate played an important role in lowering the Fe2O3 grade to less than 1% and also decreased the arsenic content. Optimisation was recommended to further reduce lithium loss to magnetic products. 9.1.2.18 Ore sorting test work at TOMRA for laser and X-Ray Transmission (XRT) sensor trade- off Representivity of test samples [§229.601(b)(96)(iii)(B)(10)(ii)] The sample for this programme was drawn from the 2016 Syväjärvi test mining sample. The sample was loaded and transported to GTK Mintec for sample preparation. For the purpose of this Performance Test, ore (2 400 kg for size fraction 30 – 60 mm and 1 200 kg for the finer-grained fraction 15 – 30 mm) and waste material (250 kg pro fraction) were dispatched to TOMRA. Testing laboratory and certification [§229.601(b)(96)(iii)(B)(10)(iii)] Testing was conducted at the TOMRA facilities in Hamburg, Germany. TOMRA certification details are provided in sub-section 9.1.2.3.’ Mineral processing testing and results Earlier studies had proven that optical sorting is efficient at removing dark-coloured waste rock for Keliber samples. Furthermore, and based on the conclusions from the previous programme, Keliber engaged Metso Outotec (TOMRA) to execute a test work programme to compare X-Ray Transmission (XRT) and laser sensor-based sorting to remove barren pegmatite and other light-coloured waste minerals from the ore feed. Unfortunately, the final report from TOMRA was not available at time of writing the 2022 DFS report but the preliminary results were available (Table 9-3). The material sample for the LASER sorting was washed since this technique requires clean and wet surfaces. Two settings were used: Setting 1 was less sensitive, where dark waste particles, including plagioclase porphyrite, metasediments and tuffs, were rejected. In addition to these rock types, some feldspar without SRK Consulting – 592138 SSW Keliber TRS Page 97 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 the spodumene inclusions were separated. The application of the more sensitive Setting 2 allowed separation of feldspar and pegmatite in addition to the dark waste particles. Based on the mass balances and chemical assays, both of the ore sorting techniques are suitable for the Keliber Lithium Project operations. Table 9-3: TOMRA ore sorting mass balance 2021 Sensor Size (mm) Feed (kg) Feed (%Li2O) Product (%Li2O) Waste (white) (%Li2O) Waste (black) (%Li2O) Total Waste (%Li2O) Recovery (%) Upgrade Waste removal (%) Laser 30-60 687 1.617 1.939 1.515 0.103 0.223 97% 1.2 19% Laser 30-60 667 1.432 1.811 0.66 0.097 0.202 97% 1.26 24% Laser 15-30 362 1.331 1.636 1.59 0.103 0.348 94% 1.23 24% Laser 15-30 365 1.192 1.64 1.113 0.108 0.438 86% 1.38 37% XRT 30-60 645 1.48 1.698 1.841 0.138 0.265 97% 1.15 15% XRT 30-60 642 1.359 1.636 0.75 0.093 0.237 97% 1.2 20% XRT 15-30 369 1.348 1.742 0.824 0.097 0.196 96% 1.29 25% XRT 15-30 366 1.234 1.704 0.672 0.097 0.265 93% 1.38 33% Results showed high lithium recovery in the range 86% to 97% for both size fractions, with mass rejection of 15 to 37%. 9.1.3 Recent conversion test work 9.1.3.1 Laboratory-scale conversion tests Conversion tests carried out prior to 2017 were of small scale. In the Länttä ore pilot test of 2016 (sub-section 9.1.2.1), thermal conversion tests were conducted at 1000ºC and a retention time of one hour was found to be sufficient to convert alpha-spodumene to leachable beta-spodumene. The Syväjärvi concentrate produced in laboratory scale tests in 2016 (sub-section 9.1.2.2) was also treated in a furnace prior to autoclave testing. The Syväjärvi concentrate was found to behave in a similar way to the Länttä concentrate. 9.1.3.2 Conversion pilot for Syväjärvi concentrate by Metso Minerals in 2017 The spodumene concentrate derived from the Syväjärvi sample processed in the 2016 - 2017 mineral processing pilot plant (sub-section 9.1.2.3) was tested in three stages. • Firstly, a small amount of concentrate was converted in an indirectly heated laboratory scale rotary kiln at the Outotec Research Laboratory. A temperature of 1010ºC for 30 minutes was sufficient to convert alpha-spodumene to leachable beta-spodumene; • The second test was carried out in Development Center, Danville, PA, USA. The sample was prepared by combining two concentrate samples produced in mineral processing pilot test at GTK (GTK certification details are provided in sub-section 9.1.2.1, 150 kg from Outotec Frankfurt research centre and about 400 kg sent from GTK Mintec. For the conversion tests, the as- received subsamples were mixed in weight ratios 31.36% and 68.64%. Lithium grades of the samples were 2.35% (5.06% Li2O) and 2.34% (5.04% Li2O), respectively. The main target of the test programme was to practise the conversion process and collect operational and material characteristics for the design of commercial conversion equipment for production of material to achieve greater than 95% alpha- to bet- spodumene conversion. A secondary objective was to produce product for subsequent lithium pressure leaching tests; and • A directly heated rotational drum furnace fired with propane gas was employed to complete eight conversion tests, with temperatures ranging from 1000ºC to 1075ºC. It was concluded that the targeted 95% conversion rate was achieved. SRK Consulting – 592138 SSW Keliber TRS Page 98 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 9.1.3.3 Conversion tests with Syväjärvi and Rapasaari concentrate 2018 In relation to hydrometallurgical testing for Syväjärvi and Rapasaari concentrates, laboratory conversion tests were also run by Outotec. The conversion was executed in a batch chamber furnace at temperatures of 990°C, 1010°C, 1030°C and 1060°C using three hours’ retention time. Conversion of the samples were confirmed by XRD. SEM study on the 1060°C Rapasaari sample showed some melted structures on the spodumene grains, which resulted in lower lithium recoveries in leaching. 9.1.3.4 Conversion pilot for Syväjärvi concentrate by FLSmidth in 2018 (DFS) The third test series was carried out with a directly fired rotary-kiln at FLSmidth Inc. Pyromet Technology testing facilities, Bethlehem, PA, USA. The sample used was concentrate produced in mineral processing pilot test at GTK (GTK certification details are provided in sub-section 9.1.2.1. The test programme had two targets: (i) to evaluate the physical, thermal and phase conversion properties of a spodumene concentrate sample and (ii) to produce bulk converted sample for subsequent pilot-scale lithium pressure leaching tests. According to FLSmidth’s assays, the lithium grade of the bulk sample was 5.57% Li2O analysed with Atomic Absorption Spectroscopy (AAS) and spodumene content about 74 to 75% analysed with X-Ray Diffraction (XRD). The concentrate was held for 30 minutes at 1100°C. Conversion recovery result was 97.5%. The specific gravity of the material decreased from feed level value of 3.04 g/cm3 to 2.36 g/cm3 mainly because of the spodumene phase conversion. 9.1.3.5 Conversion pilot for Syväjärvi concentrate by FLSmidth in 2019 A pilot test programme was performed to evaluate the conversion of alpha-spodumene to beta-spodumene using a two-stage cyclone preheater rotary calciner system, followed by product comminution using an open circuit ball mill. The material received for this study included ~3 000 kg of flotation concentrate containing 10.6% moisture and 4.75% Li2O. The solids residence time in the rotary kiln was two hours and the burning zone solids temperature was generally maintained between 1050 - 1100°C. These conditions resulted in an overall average alpha- to beta-spodumene conversion level of 96.9%, as measured by the sulphuric acid solubility method. Stable, sinter-free operation of the preheater kiln system was demonstrated along with a high conversion to beta-spodumene when calcining flotation concentrate. The dusting rate was considered very low. Based on the results of the pilot programme, no adjustments are required to the commercial calcining being offered by FLSmidth. 9.1.4 Recent hydrometallurgical testing for production of lithium carbonate and lithium hydroxide The June 2018 DFS considered the production of battery-grade lithium carbonate. However, following further market studies it was decided to consider the production of battery-grade lithium hydroxide instead of lithium carbonate. As a consequence, much of the hydrometallurgical test work undertaken was directed at producing lithium carbonate. While not totally applicable, such test programmes are briefly summarised here. 9.1.4.1 Laboratory and pilot test for Länttä concentrate in 2015 The feed material for the testing was from the previous GTK Mintec Länttä 2015 programme (GTK certification details are provided in sub-section 9.1.2.1). Suitable composite samples were prepared so that the feed sample had an average head grade of 4.5% Li2O. Lithium yields in laboratory batch leaching and bi-carbonation tests were low, with 86% being the best result achieved. A higher lithium yield of 91% was, however, obtained in the pilot-plant leaching and bi- carbonation tests. Ion exchange was used to remove metal impurities such as Ca and Mg from the leach solution. The purified solution from the ion exchange was heated above 90°C to crystallise Li2CO3. The Li2CO3 product contained 17.3 to 18.6% lithium, with phosphorus and silicon being the main impurities. The Bond ball mill work index for the beta-spodumene was determined as 11.51 kWh/t. SRK Consulting – 592138 SSW Keliber TRS Page 99 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 9.1.4.2 Laboratory tests for Syväjärvi concentrates 2016 The main objective of the programme was to confirm the leaching parameters for the Syväjärvi spodumene flotation concentrate produced in the previous GTK Mintec Syväjärvi 2015 batch flotation. Based on the solid fraction analyses, the lithium leaching yield was 95.6%. 9.1.4.3 Laboratory and pilot tests for Syväjärvi concentrates 2017 Feed material was concentrated that had been converted for subsequent hydrometallurgical tests at Outotec Frankfurt Research Centre (sub section 9.1.3.2). The programme included the following items: • Thermal conversion tests of alpha-spodumene to leachable beta-spodumene in a laboratory rotary kiln; • Pressure leaching and bi-carbonation tests; • Solid liquid separation tests of the leach residue (Analcime); • Ion exchange tests; • Crystallisation tests of Li2CO3; and • Solid liquid separation tests of the lithium carbonate product (Analcime). The converted beta-spodumene material was used in leaching and bi-carbonation tests which yielded from 86% to 95% lithium in the batch tests, and 84% to 87% in the pilot plant operation. Ion exchange was used to remove metal impurities such as Ca and Mg from the leach solution. The purified solution from the ion exchange was heated above 95°C to crystallise Li2CO3. The Li2CO3 product contained 17.3% to 19.0% lithium, with phosphorus and silicon being the main impurities. In thickening tests, the leach residue slurry settled to an underflow density of 48% and the overflow clarity was between 70 ppm and 250 ppm. The required flocculant dosage was 20 g/t of Superfloc N100. In filtration tests, cake moistures of 30% and 44% were achieved pressure filtration and vacuum filtration, respectively. No difference was observed in the lithium recoveries between pressure or vacuum filtration for the un-thickened leach residue slurry. With the thickened leach residue slurry, however, the pressure filtration was more efficient and filtration capacities were higher. 9.1.4.4 Laboratory tests for Syväjärvi concentrates 2017 The test programme included soda leaching tests in a batch-scale autoclave of the concentrate that had been converted during the Metso Minerals pilot-scale conversion tests described above (sub section 9.1.3.2). This programme was conducted at Outotec’s facilities. Alpha-spodumene was not detected in the XRD analysis indicating that the conversion to beta-spodumene was complete. Based on the solid fraction analyses over five batch tests, the lithium yield varied from 79 to 89%. 9.1.4.5 Laboratory tests for Syväjärvi and Rapasaari concentrates 2018 The feed material was produced in the previous Syväjärvi 2017 test programme (sub section 9.1.3). Recent Conversion Test Work: Conversion Tests with Syväjärvi and Rapasaari Concentrate 2018). The programme comprised laboratory testing of conversion, soda leaching, bi-carbonation, ion exchange and crystallisation. Lithium carbonate was produced by crystallisation from Syväjärvi and Rapasaari concentrates. Leaching and bi-carbonation tests were conducted on the converted concentrate in a laboratory autoclave. The autoclave temperature was 220°C with carbon dioxide introduced at a pressure of 3 Bar and a temperature of 30°C. The following lithium yields were obtained in the programme: • 90 - 95% for the Syväjärvi_2018 concentrate; • 91 - 96%% for the Syväjärvi_2017 concentrate; and • 88% for the Rapasaari concentrate at 1010°C and 84% at 1060°C.
SRK Consulting – 592138 SSW Keliber TRS Page 100 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SEM study from the calcined Rapasaari concentrate and leach residues revealed that some spodumene grains were covered by melted phase, which decreased the lithium leaching yield compared with the Syväjärvi concentrates. Lithium carbonate was produced by crystallisation with and without the ion exchange step. Results confirmed that it is possible to produce over 99.5% lithium carbonate end product without the ion exchange step from Syväjärvi samples. The ion exchange, however, decreased the calcium level from 0.02 – 0.05% to less than 0.01%. 9.1.4.6 Lithium hydroxide pilot processing at Outotec 2019 - Syväjärvi Metso Outotec's patented Lithium Hydroxide process for production of battery-grade lithium hydroxide includes three key unit processes: • Alkaline pressure leaching; • Lime conversion leaching; and • Lithium hydroxide monohydrate crystallisation. Feed to the two-stage alkaline leach process is beta-spodumene concentrate after calcining. Lithium is first extracted using soda ash pressure leaching, resulting in the formation of soluble lithium carbonate (Li2CO3) and mineral component analcime (NaAlSi2O6·H2O) as the main components. In the second stage lithium carbonate is solubilised in a conversion reaction, producing lithium hydroxide solution and solid calcium carbonate, which will report together with other mineral residues. The alkaline hydroxide and carbonate processing environment ensures very low solubilities of the main impurity elements and compounds, including Fe, Al, Mg, Ca, B, and P, reducing the need for additional impurity removal or precipitation. The Pregnant Leach Solution containing lithium hydroxide is a suitable feed for polishing with Ion Exchange ahead of crystallisation of the final LiOH monohydrate product. The object of the 2019 test work programme was to study lithium hydroxide production by soda pressure leaching and to produce small amounts of the product for marketing purposes. A beta-spodumene concentrate sample from conversion in rotary kiln, called 2018 calcine, was the main concentrate used in this work. In addition, comparative hydrometallurgical test work was carried out with a concentrate from 2017, which was calcined in a chamber furnace in Oberursel, Germany by Outotec. Based on the chemical analysis of the calcine samples, they had similar compositions. The lithium concentration of the 2018 calcine was 2.55% Li (5.49% Li2O) and that of the 2017 calcine was 2.39% Li (5.15% Li2O). Batch tests were carried out for the soda leaching and LiOH conversion process steps, to produce information for the pilot operation. The solids analysis showed that 88% lithium extraction was achieved in the LiOH conversion. 9.1.4.7 Lithium hydroxide continuous pilot processing at Outotec 2020 - Syväjärvi The Syväjärvi beta-spodumene concentrate used in this hydrometallurgical test work was calcined in the FLSmidth pilot run in 2019. The average lithium concentration of the calcines corresponded to a 4.53% Li2O concentration. Soda leaching, cold conversion and secondary conversion batch tests were carried out to verify the lithium extraction as well as to produce information for the planning of the continuous pilot. The continuous LiOH pilot was operated for 14 days. The main process stages in the process were soda leaching, cold conversion, secondary conversion, ion exchange, LiOH crystallisation and mother liquor carbonation. Leaching was carried out in a 65 l titanium autoclave at a target temperature of 220°C and target residence time of two hours. (Figure 9.8). SRK Consulting – 592138 SSW Keliber TRS Page 101 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project 65-litre Autoclave used in the semi-continuous pilot processing Project No. 592138 Figure 9.8: 65-litre Autoclave used in the semi-continuous pilot processing Slurry was flashed off from the autoclave to a flash vessel with 80°C temperature and atmospheric pressure. Slurry from the autoclave was filtered by pressure filter, with solids being washed with water. Pulped soda leach residue and lime slurry were pumped to the first 20 l cold conversion reactor, from where the slurry was transferred as overflow to the second 20 l reactor and subsequently, to the filter feed tank. Target temperature in cold conversion was 30°C and residence time was about two hours. Both reactors as well as the filter feed tank were equipped with nitrogen gas feed. Slurry from the cold conversion was filtered by pressure filter then filtrate was pumped to the secondary conversion feed tank. Solids were washed with water. The wash filtrate was then used in pulping of the soda leach residue and lime slurry preparation. The filtrate from the second pressure filter and lime slurry were pumped to a 20 l stainless steel reactor for secondary conversion. The residence time in secondary conversion was over two hours and the temperature was ambient. The overflow from the reactor was collected to the feed tank of a filter press polishing filter. Ion exchange was operated continuously during the pilot with a feeding rate based on the availability of feed solution, with two columns in series. Crystallisation was carried out at approximately 77°C. Lithium hydroxide slurry was thickened to solids concentration of 40 - 50% and fed to a pusher centrifuge. Battery-grade lithium hydroxide (Na <50 ppm, K <20 ppm) was produced with a higher wash ratio of 0.17 m3/t. Lithium hydroxide monohydrate was dried in a shaking fluid bed dryer. Nitrogen gas was used for drying. It was reported that the objectives of the pilot were mostly met. The consumption of reagents was investigated and the impact of recycling different process streams on the process was observed. The soda leach circuit was stable, with stable concentrations of Na and K. The cold conversion circuit also proved to be stable. The impurities in the cold conversion solutions stabilised at a low level, with Na having a slight increasing trend. The Li extraction in the soda leaching and cold conversion process stages was initially low, but after adjustments were made to the operating conditions, high levels of extraction were achieved. The operation of the crystallizer had its own challenges related to the differences in the production capacity of the equipment in comparison to the rest of the process. However, a production of approximately 35 kg of moist lithium hydroxide monohydrate product from the centrifuge was achieved. One batch of the SRK Consulting – 592138 SSW Keliber TRS Page 102 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 centrifuge product was successfully dried with a fluidized bed dryer as well. The product purity achieved with a single crystallisation stage was extremely high. With a second crystallisation, the impurity levels in the crystals could be decreased even further, with Na and K both being <10 ppm. The Si concentration in the crystals was also decreased by the second crystallisation stage 9.1.4.8 Lithium hydroxide continuous pilot processing at Outotec 2022 - Rapasaari Feed sample The Rapasaari spodumene concentrate produced in the GTK Mintec pilot plant was calcined in a continuous rotary kiln by FLSmidth in North America, after which it was shipped to Pori, Finland for hydrometallurgical test work. Test programme This programme including batch leaching test work as well as continuous piloting of the Metso Outotec LiOH Process, was carried out between April and June 2022. A simplified block diagram of the process flowsheet is shown Figure 9.9. SSW Keliber Lithium Project Simplified process flowsheet of LiOH*H2O production Project No. 592138 Figure 9.9: Simplified process flowsheet of LiOH*H2O production β-spodumene calcine was initially pulped with water and recycled process solutions. Sodium carbonate was simultaneously fed and dissolved according to the following reaction: Na2CO3(s) → 2 Na+ + CO3 2- Operating conditions in the pressure leaching autoclave are typically 200 to 220 °C and approximately 20 bar. β-spodumene reacts to form lithium carbonate and analcime solids according to the following reaction: 2 LiAlSi2O6(s) + Na2CO3 + H2O → Li2CO3(aq, s) + 2 NaAlSi2O6·H2O(s) Some of the lithium remains solubilised, but it is mostly present as a solid lithium carbonate in the leach residue, along with analcime. Autoclave discharge is cooled ahead of solid/ liquid separation, with solids content being forwarded to LiOH conversion. SRK Consulting – 592138 SSW Keliber TRS Page 103 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Pressure leach residue is pulped with water and lime. Calcium hydroxide reacts with the lithium carbonate to form more soluble lithium hydroxide and calcium carbonate, which is precipitated. This reaction is carried out at slightly elevated temperature to limit the solubility of impurities such as aluminium and silicon. The conversion reaction takes place according to the following reaction equation: Li2CO3 (s) + Ca(OH)2 (aq) → 2 LiOH (aq) + CaCO3 (s) After the LiOH conversion, solids and liquid are separated and the solid residue, mainly calcium carbonate and analcime, is the main residue of the process. The filtrate is fed to a secondary conversion stage, where impurities, such as Al and Si are removed from the solution by addition of a small amount of lime. After the secondary conversion, the solution is fed via polishing filtration to ion exchange for the removal of residual divalent metal cations such as calcium and magnesium before crystallisation. The purified lithium hydroxide solution is fed to the crystallisation stage, where lithium hydroxide monohydrate is crystallised under vacuum from the purified LiOH solution. Some of the crystallisation mother liquor is fed to carbonation. Carbon dioxide gas is fed to the solution and lithium hydroxide is converted to lithium carbonate, which precipitates due to its lower solubility. 2 LiOH (aq) + CO2 (g) → Li2CO3 (aq, s) + H2O The product slurry from mother liquor carbonation can be fed to the slurry preparation stage of the soda leaching circuit. Test results The average lithium concentration of the calcines corresponded to a 5.5% Li2O concentration. Soda leaching, cold conversion and secondary conversion batch tests were carried out to verify the lithium extraction as well as to produce information for the planning of the continuous pilot. The continuous LiOH pilot was operated for approximately 17 days. The main process stages in the process were soda leaching, cold conversion, secondary conversion, ion exchange, LiOH crystallisation and mother liquor carbonation as previously described for Syväjärvi. The first stage crystallisation was continuously operated. The average levels of the typical impurities were ~30 ppm Al, 311 ppm Na, 118 ppm Si and 39 ppm K. During the pilot three samples of the 1st stage LiOH·H2O products were redissolved and fed to 2nd crystallisation, which was carried out with a rotary evaporator. It was reported that the results of the chemical analyses of the samples were excellent and in terms of impurity concentrations, the final products corresponded to the specification of battery grade LiOH·H2O provided by Keliber. Almost all impurities were below detection limits, such as Al<5 ppm, K<10 ppm, Cl<20 ppm, F<50 ppm, SO4<150 ppm and most of the heavy metals being either <1 or <2 ppm. Some Na and Si were detected in two of the samples, but the concentrations were according to the client’s specification as well with Na being mostly <30 ppm and Si mostly <20 ppm. Based on LiOH concentrations of both the 1st and 2nd stage samples, there was some residual moisture in the products. 9.1.5 Recovery dependencies in mineral processing of Syväjärvi, Rapasaari and Länttä Based on bench scale and pilot scale test results undertaken between 2001 and 2017, Keliber developed recovery functions for the main deposits, Syväjärvi, Rapasaari and Länttä. Not all test results were used, with successful and representative tests being chosen. Based on the test results, it was noted that lithium recovery is dependent on the following key factors: • Deposit from where the sample originated • Li2O grade of the sample (feed of the test) • Wall rock dilution – wall rock quality and dilution quantity (%) • Scale of the test (laboratory vs pilot) • Concentrate grade Keliber’s basic engineering is based on producing 4.5% Li2O concentrate. Therefore, the concentrate grade is fixed at 4.5% and only the effect of other parameters was studied.
SRK Consulting – 592138 SSW Keliber TRS Page 104 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 9.1.5.1 Deposit The deposits differ from each other by their flotation response. Test results showed that Syväjärvi performed best. Rapasaari was very similar to Syväjärvi with slightly lower recoveries, but Länttä showed poorer floatation behaviour. 9.1.5.2 Head grade Test results confirmed a clear relationship between lithium feed grade and lithium recovery. Laboratory scale results for pure ore samples without dilution are shown in Figure 9.10. SSW Keliber Lithium Project Lithium recovery at 4.5% Li2O in the concentrate vs lithium grade in the feed Project No. 592138 Figure 9.10: Lithium recovery at 4.5% Li2O in the concentrate vs lithium grade in the feed 9.1.5.3 Wall rock dilution Wall rock dilution reduces the head grade which would result in lower recoveries, but it was shown that the impact is much stronger than the head grade decrease would cause. The grade-recovery curves of the dilution tests included in the geo-metallurgical study are shown Figure 9.11. SRK Consulting – 592138 SSW Keliber TRS Page 105 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Syväjärvi Rapasaari Länttä Emmes SSW Keliber Lithium Project Grade recovery curves of the geo-metallurgical dilution study Project No. 592138 Figure 9.11: Grade recovery curves of the geo-metallurgical dilution study Observed differences between the deposit are largely explained by the modal composition of the host rocks as summarised in Table 9-4. SRK Consulting – 592138 SSW Keliber TRS Page 106 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Table 9-4: Modal composition of the waste rocks of Syväjärvi, Länttä and Rapasaari Mineral Deposit Syväjärvi Länttä Länttä Rapasaari Waste/ Country Rock Plagioclase Porphyrite Amphibolite Tourmaline Mica Schist Quartz 8.90 6.60 13.21 30.85 Plagioclase 46.63 33.46 4.49 13.92 Microcline 1.32 0.44 0.07 1.75 Spodumene 0.36 0.00 0.01 0.02 Muscovite 0.19 0.08 10.26 15.09 Epidote 1.58 6.10 1.86 0.00 Biotite 18.60 8.15 13.97 34.91 Tourmaline 0.00 1.79 45.05 2.38 Amphiboles 19.24 40.05 0.04 0.03 Other Mafics 1.62 2.37 0.80 0.34 Others 1.56 0.96 10.24 0.71 TOTAL 100.00 100.00 100.00 100.00 Mafic Minerals 39.46 52.36 59.86 37.66 Sheet Silicates 18.79 8.23 24.23 50.00 The impact of dilution on metallurgical results was also shown to be dependent on the MgO content where it was shown that where the feed samples included dilution, the final concentrate had higher MgO contents than in the tests without dilution as shown in Figure 9.12. SSW Keliber Lithium Project Recovery at 4.5% Li2O against MgO% of the feed sample Project No. 592138 Figure 9.12: Recovery at 4.5% Li2O against MgO% of the feed sample Fitted lines for lithium recovery into the spodumene concentrate vs wall rock dilution in the feed sample are shown for Syväjärvi, Rapasaari and Länttä in Figure 9.13. SRK Consulting – 592138 SSW Keliber TRS Page 107 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 - SSW Keliber Lithium Project Fitted lines for lithium recovery into the spodumene concentrate vs wall rock dilution in the feed sample Project No. 592138 Figure 9.13: Fitted lines for lithium recovery into the spodumene concentrate vs wall rock dilution in the feed sample 9.1.5.4 Ore sorting Ore sorting operates practically in particle size fractions 20-40 mm and 40-100 mm whereas the 0-20 mm particle size fraction is not sorted due to small particle size and thus will by-pass sorting. Based on Syväjärvi pilot ore mass balance, it was shown that ore sorting was capable of removing 10.9% of the mass when the wall rock dilution was 15%. This equates to 73% efficiency in the sorter. Thus, it was assumed that 73% of the waste rock is removed from all ore types by the ore sorter, while fines are bypassed. 9.1.5.5 Scale-up from laboratory- to full-scale Keliber considered a number of factors in comparing laboratory and pilot scale test results. This included slime removal, flotation residence time, losses in cleaning stages, entrainment, rheological factors and others. Given challenges such as operating cyclones at pilot scale, it was considered fair to assume that full scale operations could be optimized, and lithium losses could be minimized. Therefore, it was estimated that the scale up factor from laboratory to the full scale would be slightly lower than observed and a conservative value of 1.27 percentage points was used. 9.1.5.6 Summary recovery functions [§229.601(b)(96)(iii)(B)(10)(iv)] The final recovery formula applied to mine planning and financial modelling is as follows: Recovery = 100-P1*(ore grade)^P2-P3*(%dilution)-P4 Where: P1 = Grade parameter 1; multiplier P2 = Grade parameter 2; exponent P3 = Dilution parameter P4 = Scale-up parameter Individual parameters per deposit are shown in Table 9-5.
SRK Consulting – 592138 SSW Keliber TRS Page 108 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Table 9-5: Recovery parameters Parameter Syväjärvi Länttä Rapasaari Outovesi Emmes P1 (%) Grade parameter 1; multiplier 10.6 15.0 11.3 11.3 11.3 P2 (%) Grade parameter 2; exponent -0.88 -0.88 -0.88 -0.88 -0.88 P3 (%) Dilution parameter -0.33 -0.557 -0.272 -0.26 -0.06 P4 (%) Scale-up parameter -1.27 -1.27 -1.27 -1.27 -1.27 Modelled parameters included in the Technical Economic Model are shown for each deposit in Table 9-6. Recoveries are shown for selected months with block grades around 1% Li2O for comparative purposes. Table 9-6: Modelled lithium recoveries included in the Technical Economic Model Parameter Unit Syväjärvi Open Pit Jun-28 Rapasaari Open Pit Feb-30 Rapasaari U/ground Jun-34 Lanta Open Pit Dec-38 Lanta U/ground Sep-40 Outovesi Open Pit Jun-39 Emmes U/ground Jan-40 Ore Grade in Block % Li2O 0.99 1.00 1.00 0.98 0.80 1.18 1.01 Block wall rock dilution % 14.30 21.94 36.87 26.92 40.89 29.42 25.57 Block mass tonnes 64 142.09 61 540.05 12 443.80 43 889.97 51 336.00 25 915.98 28 876.49 Ore Grade % (without dilution) % Li2O 1.16 1.28 1.58 1.34 1.35 1.67 1.36 Sorter efficiency % % 73.00 73.00 73.00 73.00 73.00 73.00 73.00 p1 - Grade parameter / multiplier % 10.60 11.30 11.30 15.00 15.00 11.30 11.30 p2 - Grade parameter / exponent % -0.88 -0.88 -0.88 -0.88 -0.88 -0.88 -0.88 p3 - Dilution parameter -0.33 -0.27 -0.27 -0.56 -0.56 -0.26 -0.06 p4 - Scale up parameter for full scale -1.27 -1.27 -1.27 -1.27 -1.27 -1.27 -1.27 p5 - Scale up parameter for pilot scale -5.42 -5.42 -5.42 -5.42 -5.42 -5.42 -5.42 Targeted Concentrate Grade % Li2O 4.50 4.50 4.50 4.50 4.50 4.50 4.50 Corrected Li2O Recovery % in full scale - Final value % 88.00 87.71 87.47 82.11 78.41 88.89 89.61 Conversion degree % 97.00 97.00 97.00 97.00 97.00 97.00 97.00 Hydro Li2O Yield % 86.00 86.00 86.00 86.00 86.00 86.00 86.00 Conversion + Hydro Li2O Yield % 83.42 83.42 83.42 83.42 83.42 83.42 83.42 Global Lithium Yield % 73.41 73.17 72.96 68.50 65.41 74.15 74.75 LiOH.H2O tonnes 1 314.61 1 262.77 254.19 828.10 750.29 634.65 614.16 9.1.6 Adequacy of data [§229.601(b)(96)(iii)(B)(10)(v)] 9.1.6.1 Ore Sorting Ore sorter performance was based on pilot-scale tests undertaken at equipment manufacturers’ test facilities (Binder & Co, Redwave and TOMRA). Early tests focussed on optical sorting for the removal of dark waste from ore. More recent tests have assessed Laser and XRT sorting. Optical ore sorting was found to be effective in removing black waste rock from the composite ore feed. With Laser and XRT sorting, dark waste particles, including plagioclase porphyrite, metasediments and tuffs, were rejected. In addition to these rock types, some feldspar without the spodumene inclusions were separated. In all cases, the feed to the ore sorting equipment comprised an artificial blend of Syväjärvi ore and waste rock. A limited ore sorting programme is reportedly planned to be undertaken on Rapasaari OP ore. SRK Consulting – 592138 SSW Keliber TRS Page 109 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Based on pilot-scale XRT ore sorting test results conducted on the Syväjärvi bulk ore sample, it was concluded that ore sorting is 73% efficient. There is a risk that ore sorting efficiency will vary across the Syväjärvi deposit. It is accordingly recommended that ore sorting variability tests be conducted across the Syväjärvi deposit. It was further assumed that the same efficiency would apply to other ore sources and ore types. There is a risk that other deposits will not perform with the same efficiency. It is accordingly recommended that these deposits be subjected to pilot ore sorting and variability tests using XRT ore sorting technology. The feed to the ore sorting test equipment comprised an artificial blend of Syväjärvi ore and waste rock. There is a risk that performance on mined ore may be less efficient than on the artificial composite ore feed. It is accordingly recommended that samples of mined ore from all deposits be subjected to pilot ore sorting tests using XRT ore sorting technology. 9.1.6.2 Desliming The Syväjärvi pilot test conducted in 2019 reported that de-sliming was more efficient with two-stage desliming cyclones. The P80 value of slimes was 7 µm, whereas in the 2016 test the corresponding P80 value was 16 µm. The smaller sizing reduced the Li2O loss to tailings from 6.3% in the 2016 pilot operation down to 4.7% level in the 2019 test. The proposed process route includes two-stage desliming with hydrocyclones ahead of flotation, but no specific allowance has been made in recovery estimates for desliming losses. 9.1.6.3 Flotation Since 2015, flotation tests were conducted on various ores at bench and pilot-scale: • Bench: Länttä, Syväjärvi, Rapasaari, Emmes and Outovesi; and • Pilot: Länttä, Syväjärvi and Rapasaari. Flotation parameters are reasonably well understood but it is recommended that pilot-scale tests be undertaken on the other main sources of ore. In 2016 - 2017, a geo-metallurgical study was undertaken on 18 mineralised samples collected from the Syväjärvi, Länttä and Rapasaari deposits to assess differences in grindability and flotation performance. Furthermore, ore variability flotation tests were undertaken on Rapasaari samples selected from four different mineralised material types. These showed significant variability. It is recommended that similar variability programs be undertaken on all other deposits to ensure adequate understanding of spatial variability in flotation performance. Ultimately this should extend into the development of geo-metallurgical models for all deposits. 9.1.6.4 Conversion The objective of conversion is to convert alpha-spodumene to leachable beta-spodumene. Since 2016, conversion tests have been conducted on various concentrates at bench and pilot-scale: • Bench: Länttä, Syväjärvi and Rapasaari; and • Pilot: Länttä, Syväjärvi and Rapasaari. Conversion parameters are reasonably well understood but it is recommended that pilot-scale tests be undertaken on the other main sources of concentrate. 9.1.6.5 Soda leaching and final product production From 2015 to 2017, bench and pilot scale tests were undertaken on Länttä and Syväjärvi concentrates including the major process stages, from the spodumene concentrate conversion to lithium carbonate. In 2018 bench tests were undertaken on Syväjärvi and Rapasaari concentrates, including conversion, soda leaching, bi-carbonation, ion exchange and lithium carbonate crystallisation. Following the decision to produce lithium hydroxide rather than lithium carbonate, semi-continuous bench- scale tests were undertaken in 2019 to produce lithium hydroxide from a beta-spodumene concentrate generated in 2018. This was followed by continuous pilot testing of Syväjärvi concentrate in 2020 and Rapasaari concentrate in 2022. The beta-spodumene concentrates used in this hydrometallurgical test work was calcined in the FLSmidth pilot runs in 2019 and 2021 respectively. The continuous LiOH.H2O SRK Consulting – 592138 SSW Keliber TRS Page 110 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 pilot was operated for 14 and 17 days respectively. The main process stages were soda leaching, cold conversion, secondary conversion, ion exchange, LiOH.H2O crystallisation and mother liquor carbonation. The soda leach developed by Outotec has been successfully demonstrated at pilot-scale on Syväjärvi and Rapasaari beta-spodumene concentrate. Ideally, other concentrates should also be subjected to conversion and hydrometallurgical testing. However, as the spodumene pegmatites of the Kaustinen area are understood to resemble each other petrographically, mineralogically and chemically, it is likely that their concentrates will perform similarly to that from Syväjärvi and Rapasaari. Notwithstanding this, it is recommended that the mineralogical and chemical similarity of other concentrates be assessed and that they be subjected to conversion and hydrometallurgical testing if significantly different to Syväjärvi or Rapasaari. 9.1.7 Comment The spodumene pegmatites of the Kaustinen area resemble each other petrographically, mineralogically and chemically. They are typically coarse-grained, light-coloured and mineralogically similar. The main minerals are albite (37 - 41%), quartz (26 - 28%), K-feldspar (10 - 16%), spodumene (10 - 15%) and muscovite (6 - 7%), generally in this quantitative order. Studies show that the chemical, mineralogical and geo-metallurgical differences between the deposits are small. Currently, spodumene (LiAlSi2O6) is the only economic mineral identified in the pegmatite veins. Other lithium minerals, for example, petalite, cookeite, montebrasite and sicklerite, are found only as trace quantities. Beryl and columbite-tantalite are important trace minerals, with mean grades of the deposits as follows: beryllium 60 to 180 ppm; tantalum 13 to 60 ppm and niobium 17 to 60 ppm. The mean chemical compositions of the spodumene grains from three deposits analysed by GTK (Syväjärvi, Rapasaari and Leviäkangas) are as follows: • SiO2 64.78 to 65.17%; • Al2O3 26.88 to 27.01%; • FeO 0.29 to 0.55% and • MnO 0.09 to 0.13%. The Li2O content of spodumene is 7.0%, 7.21% and 7.22% for Syväjärvi, Rapasaari and Leviäkangas, respectively. Variation in the grindability between the deposits is small and geo-metallurgical studies show that the hard component in the ores is spodumene and therefore the specific grinding energy shows positive correlation with the lithium grade. In flotation response the deposits show small differences mainly due to variation in the lithium head-grade and proportion of gangue dilution. Variation in the ore texture, spodumene grain size, colour or alteration does not have an impact on processability. The wall rock dilution has been found to have a negative impact for flotation, lowering the concentrate grade. In this sense Syväjärvi, where the wall rock dilution is plagioclase porphyrite, has proven to be slightly easier to process than other deposits hosted by mica schist. Minimising the wall rock contamination in flotation is important and therefore selective mining and ore sorting will play a significant role in controlling the flotation feed. The Keliber project is likely to be the first implementation of the Metso Outotec soda pressure leaching technology. While the individual unit processes are not novel, and while the Syväjärvi (2020) and Rapasaari (2022) pilot trials have significantly de-risked the flowsheet, a residual risk remains as it does with the first implementation of any novel technology. In mitigation of such risk, the Lithium Hydroxide Refinery will commence hot commissioning on third party concentrate approximately nine months before concentrate is received from the Päiväneva concentrator. In addition, a ramp-up period of twenty four months has been allowed to achieve design throughput of Keliber concentrate. Metso Outotec will also provide a process guarantee, although such a guarantee does not ultimately guarantee that a process will work so much as it defines the extent of financial compensation that will apply should it not. SRK Consulting – 592138 SSW Keliber TRS Page 111 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 10 MINERAL RESOURCE ESTIMATES [§229.601(b)(96)(iii)(B)(11) 10.1 Key assumptions, parameters and methods used to estimate Mineral Resources [§229.601(b)(96)(iii)(B)(11)(i)] Keliber holds licences to five major lithium deposits, an advanced project and several prospects in the Kaustinen – Kokkola – Kruunupyy area in western Finland. Keliber has declared Mineral Resources on seven deposits to date: Syväjärvi, Rapasaari, Länttä, Outovesi, Emmes, Tuoreetsaaret and Leviäkangas and are described in this report. The lithium deposits are hosted by spodumene pegmatite veins with a maximum width of 30 m and maximum length of 400 m. The deepest drill intersection of one of the veins is 200 m vertically below the surface. Many of the known spodumene veins are still open at depth and along strike. All of the deposits are interpreted to be in the form of sheet-like spodumene pegmatite veins and are informed primarily by diamond drilling, and in the case of the Syväjärvi deposit, exploratory underground development exposure. The estimates have been undertaken by independent consultants to Keliber; Paul Payne (FAusIMM, CP) for Syväjärvi, Rapasaari, and Tuoreetsaaret and Markku Meriläinen (MAusIMM) and Pekka Lovén (MAusIMM, CP) for Länttä, Outovesi, Leviäkangas and Emmes. The QP has reviewed the Mineral Resource estimates and independently conducted verifications on the estimates as described below. All estimates were undertaken using Geovia’s Surpac software. The exploration data have been collected by a number of different companies prior to the acquisition by Keliber, including a number of independent companies and GTK; Keliber has also undertaken its own exploration programmes on all deposits including re-analysis of some of the drill core at Länttä and Emmes. The drill hole data available and used in the Mineral Resource estimates are summarised in Table 10-1. Table 10-1: Drill hole (and channel sample) data informing the Mineral Resource estimates Deposit Number of drill holes in database Length drilled (m) Number of drill holes drilled by Keliber Number of drill holes in Resource estimate Drilled metres in resource (m) Syväjärvi 212 17 977 121 101 11 906 Rapasaari 396 63 718 307 191 33 020 Länttä 100 9 067 51 100 9 067 Outovesi 24 1 752 0 24 1 752 Emmes 54 6 284 23 54 6 284 Leviäkangas 123 6 821 24 27 2 246 Tuoreetsaaret 50 10 617 50 16 3 592 Excluded data include percussion drilling at Syväjärvi and Leviäkangas and drill holes that did not intersect meaningful mineralisation. The drill hole databases reviewed are free from obvious data capture errors such as gaps and sample overlaps, and no collar and down-hole survey anomalies were detected. The wireframes were digitized using conventional sectional interpretation and cut-off values of approximately 0.4% to 0.5% Li2O were typically used to discriminate between mineralised and non-mineralised intersections. Drill hole spacing is variable across the orebodies, but the section lines are typically spaced approximately 40 m apart, although the spacing ranges between 20 m and 50 m in places. An example of the sectional interpretation at Syväjärvi is shown in Figure 10.1.
SRK Consulting – 592138 SSW Keliber TRS Page 112 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Syväjärvi geological interpretation example on Section 7 062 200N (Source: WSP, 2022) Project No. 592138 Figure 10.1: Syväjärvi geological interpretation example on Section 7 062 200N The orebody wireframes and drill hole data for the two largest deposits, Syväjärvi and Rapasaari, are shown in Figure 10.2. The Keliber sampling procedure is to not sample any non-pegmatite lithologies to avoid introducing non-spodumene lithium values into the dataset as the non-spodumene lithium is not recoverable in the planned processing circuit. The missing intervals within the wireframes are assigned a default value of 0.001% Li2O. There are two treatments of internal waste: • Where the waste material is large enough to be modelled and separately domained (such as in Figure 10.1) where a lithology (plagioclase porphyrite in this example) is wireframe modelled and assigned zero grade in the block model; or • Where smaller intersections of material that is not mineralized (e.g., entrained xenoliths) are present (and at times not sampled). In this instance, either the sampled grade is used, or the unsampled grade is set to the default value and used in estimating the blocks. For all the orebodies, the sampling length is variable, but typically ranges between one and two metres. All the deposits were composited at 2 m intervals, with the composite interval varied so as not to exclude any interval within the wireframes, resulting in composites of approximately 2 m length, but where no sampled material is excluded from the composites. The Li2O grade distributions are close to normally distributed (not considering the population of un-mineralised samples which form a distinct peak) to weakly positively skewed. Due to the low skewness, and absence of extreme outlier values, capping was not considered necessary. SRK Consulting – 592138 SSW Keliber TRS Page 113 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Syväjärvi SRK Consulting – 592138 SSW Keliber TRS Page 114 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Syväjärvi Rapasaari SSW Keliber Lithium Project Syväjärvi (looking east) and Rapasaari (looking northeast) orebody overview (Source: Payne Geological Services, 2021) Project No. 592138 Figure 10.2: Syväjärvi (looking east) and Rapasaari (looking northeast) orebody overview For Syväjärvi, Rapasaari, Tuoreetsaaret, and Leviäkangas, the block models are orthogonal to the cardinal directions, while for the other deposits the block models are rotated around the Z-axis to be approximately parallel to the strike of the veins. Most block models have dimensions of 5 m x 10 m x 5 m along the original X-, Y- and Z-axes. At Emmes the parent blocks are larger at 10 m x 15 m x 10 m, and at Leviäkangas the blocks are 10 m x 10 m x 5 m. The smaller deposits (Länttä, Outovesi, Emmes and Leviäkangas) do not have sufficient data to be able to generate robustly structured semi-variograms and have been estimated using inverse distance squared or cubed weighting of the 2 m composite datasets within each wireframe. At Rapasaari, mineralisation continuity for Li2O was examined via semi-variograms for the main sub-vertical pegmatite bodies SRK Consulting – 592138 SSW Keliber TRS Page 115 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 (Domains 9, 29, 37) and the main flat-dipping pegmatite (Domain 18), as shown in Figure 10.3. The modelled semi-variograms were applied to the smaller domains with similar orientations. SSW Keliber Lithium Project Rapasaari main pegmatite bodies selected for variography (showing search ellipses) (Source: Payne Geological Services, 2021) Project No. 592138 Figure 10.3: Rapasaari main pegmatite bodies selected for variography (showing search ellipses) At Syväjärvi only the main pegmatite orebody (shown in yellow in Figure 10.2) has been modelled with semi-variograms. The remainder of the domains borrowed the main pegmatite semi-variogram for estimation. At Tuoreetsaaret the semi-variograms were modelled only for Domain 2 (red wireframe in Figure 10.4) and borrowed for the estimates of the other four modelled pegmatite bodies. The modelled semi-variogram parameters are detailed in Table 10-2.
SRK Consulting – 592138 SSW Keliber TRS Page 116 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Tuoreetsaaret pegmatite bodies (Source: Payne Geological Services, 2022) Project No. 592138 Figure 10.4: Tuoreetsaaret pegmatite bodies Table 10-2: Modelled semi-variogram parameters for Syväjärvi, Rapasaari and Tuoreetsaaret Deposit Domain Orientation Nugget Sill 1 Range 1 Sill 2 Range 2 Strike Plunge Dip Plunge Strike Across orebody Plunge Strike Across orebody Rapasaari Major Steep (29) 230 -48 0 0.2 0.38 30 20 3.3 0.42 90 60 10 Minor Steep (9) 233 -56 0 0.25 0.07 75 65.2 7.5 0.68 115 100 11.5 Southern Steep (37) 275 -75 0 0.15 0.16 60 50 10 0.69 90 75 15 Flat/East-West (18) 100 0 -35 0.07 0.27 100 62.5 7.5 0.66 160 100 12 Syväjärvi Main Pegmatite 335 -15 5 0.10 0.67 13 6.5 2.6 0.23 70 35 14 Tuoreetsaaret Domain 2 10 0 -85 0.15 0.27 106 63.5 7.8 0.58 150 90 11 The semi-variograms presented by Keliber, and those modelled independently, do not show very robust structures, feature relatively short ranges, and are ambiguous to accurately model. For Syväjärvi, Rapasaari, and Tuoreetsaaret, a kriging neighbourhood analysis was undertaken to determine the optimal search parameters, while for the remaining deposits the typical drill hole spacing was used as a guide for the first search range. The search parameters applied are summarised in Table 10-3. For the Kriged domains the search ranges listed are for the direction of longest continuity (see Table 10-2 for the orientations of rotated axes), and the intermediate and across-orebody search distances; these are between 63% to 83% and 17% to 25% of the long range listed, respectively. For the inverse distance estimates (see below) the searches are isotropic as this method does not consider anisotropy in the weightings. SRK Consulting – 592138 SSW Keliber TRS Page 117 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Table 10-3: Search parameters for all Keliber deposits Deposit Minimum Comps Maximum Comps First Search (m) Second Search (m) Third Search (m) Rapasaari 6 20 60 90 120 Syväjärvi 4 15 40 80 120 Länttä 3 15 40 80 Outovesi 3 15 40 80 160 Emmes 3 15 40 80 Leviäkangas 3 15 75 Tuoreetsaaret 6 16 60 90 120 Using the above search parameters, Li2O grades are interpolated into the block models, within the orebody wireframes. The wireframes are treated as hard domain boundaries i.e., only samples within that wireframe/domain are used to estimate the blocks within the wireframe. Where there are sufficiently robust semi-variograms modelled for the deposit, Ordinary Kriging (OK) has been used for the interpolation. OK was applied for all domains at Syväjärvi and Tuoreetsaaret, and the majority of domains at Rapasaari (for domains defined by four drill holes or less, inverse distance squared was used). At Länttä, Outovesi, Emmes, and Leviäkangas, inverse distance cubed weighting was applied. Density was not estimated into the block model as density was not routinely measured on all samples. Table 10-4 summarises the database of density measurements, and the mean values applied to each block model. The exception to this process is at Tuoreetsaaret where a relationship between density and Li2O grade was modelled based on the data within the wireframes. A regression formula (Density = (0.0527 * Li2O) + 2.6501) was used to assign the density based on the estimated Li2O grade. Table 10-4: Summary of density measurements and mean values Deposit Method No Samples Mean value Rapasaari Archimedes bath 456 2.70 Syväjärvi Archimedes bath 545 2.72 Länttä Archimedes bath 57 2.72 Outovesi Archimedes bath 34 2.72 Emmes Archimedes bath 107 2.71 Leviäkangas None reported - 2.73 Tuoreetsaaret Archimedes bath 486 2.70 Figure 10.5 and Figure 10.6 present the Syväjärvi and Rapasaari block models, colour-coded according to the estimated Li2O grades. The outlines of the orebodies are displayed as lines around the block models, with the drill holes shown as black lines. The orebodies typically have a higher-grade core zone with thinner and lower grade areas on the surrounding fringes. For each deposit, Keliber consultants who generated the Mineral Resource estimates undertook a range of validations on the Mineral Resource estimates. These include independently generating composites and comparing statistics to those originally generated, visual validations comparing the grade distribution of the composites and estimates on sections, and comparisons of global statistics and swath plots between the composites and the estimates. In general, the validations show that the estimates match the composite dataset informing the estimates well and follow the spatial grade patterns of the composite dataset well. Examples of swath plots from Rapasaari for all domains estimated are shown in Figure 10.7. SRK Consulting – 592138 SSW Keliber TRS Page 118 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Plan view of the Syväjärvi resource model with Li2O grades Project No. 592138 Figure 10.5: Plan view of the Syväjärvi Mineral Resource model with Li2O grades SSW Keliber Lithium Project Isometric view looking northeast of the Rapasaari resource model with Li2O grades Project No. 592138 Figure 10.6: Isometric view looking northeast of the Rapasaari Mineral Resource model with Li2O grades The estimates match the composite grade trends well in both axes, and a similar concurrence can be seen in the domain statistical comparisons. In a small number of individual domains, where the estimates are informed by only a few composites (or where there are trends in the grade within a vein), some divergence 2490200 E 2490200 E 2490400 E 2490400 E 2490600 E 2490600 E 7 0 6 2 0 0 0 N 7 0 6 2 0 0 0 N 7 0 6 2 2 0 0 N 7 0 6 2 2 0 0 N 7 0 6 2 4 0 0 N 7 0 6 2 4 0 0 N 7 0 6 2 6 0 0 N 7 0 6 2 6 0 0 N 0 25 50 75 100 125 150 175 200 1:3000 LiO2 % [ABSENT] [FLOOR,0.2] [0.2,0.4] [0.4,0.5] [0.5,0.8] [0.8,1.2] [1.2,1.6] [1.6,2] [2,CEILING] SRK Consulting – 592138 SSW Keliber TRS Page 119 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 is observed between the source data and the estimates; however, this is generally reflected in the classification. SSW Keliber Lithium Project Rapasaari X and Y axis swath plots for all estimated domains Project No. 592138 Figure 10.7: Rapasaari X and Y axis swath plots for all estimated domains 0.0 500.0 1,000.0 1,500.0 2,000.0 2,500.0 3,000.0 0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 kT a n d D ri lle d le n gt h ( m ) Li O 2 % Y Swaths X Swath - Domain (All) Drilled Length Composite LiO2 % Model LiO2 % kT 0.0 200.0 400.0 600.0 800.0 1,000.0 1,200.0 1,400.0 0.00 0.20 0.40 0.60 0.80 1.00 1.20 7 0 6 0 1 7 0 7 0 6 0 2 1 0 7 0 6 0 2 5 0 7 0 6 0 2 9 0 7 0 6 0 3 3 0 7 0 6 0 3 7 0 7 0 6 0 4 1 0 7 0 6 0 4 5 0 7 0 6 0 4 9 0 7 0 6 0 5 3 0 7 0 6 0 5 7 0 7 0 6 0 6 1 0 7 0 6 0 6 5 0 7 0 6 0 6 9 0 7 0 6 0 7 3 0 7 0 6 0 7 7 0 7 0 6 0 8 1 0 7 0 6 0 8 5 0 7 0 6 0 8 9 0 7 0 6 0 9 3 0 7 0 6 0 9 7 0 7 0 6 1 0 1 0 7 0 6 1 0 5 0 7 0 6 1 0 9 0 7 0 6 1 1 3 0 7 0 6 1 1 7 0 7 0 6 1 2 1 0 7 0 6 1 2 5 0 7 0 6 1 2 9 0 7 0 6 1 3 3 0 7 0 6 1 3 7 0 7 0 6 1 4 1 0 kT a n d D ri lle d le n gt h ( m ) Li O 2 % Y Swaths Y Swath - Domain (All) Drilled Length Composite LiO2 % Model LiO2 % kT
SRK Consulting – 592138 SSW Keliber TRS Page 120 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 10.2 Mineral Resource estimates [§229.601(b)(96)(iii)(B)(11)(ii)] The Mineral Resources are reported in Table 10-5 on an attributable basis (Sibanye-Stillwater attributable ownership is 84.96%). The Mineral Resources are reported on an in situ basis and are reported exclusive of Mineral Reserves. The Mineral Resources, with the exception of the Emmes and Tuoreetsaaret deposits, are reported above a cut-off of 0.5% Li2O, with Emmes reported above a cut-off of 0.7% Li2O and Tuoreetsaaret above 0.4% Li2O. No geological losses are considered in the Mineral Resource reporting. Internal dilution from xenoliths and internal waste lenses has been incorporated into the estimation by dilution of the composite grades with the insertion of default low values in the unsampled un-mineralised intervals. Consideration of the potential mining constraints has been incorporated into the geological modelling, whereby intersections of the orebody less than 1.8 m to 2 m are not modelled. Table 10-5: Mineral Resource Statement (31 December 2022) for Keliber Oy operations Classification Deposit Mass (Mt) Li content (%) LCE mass (kt) Measured Syväjärvi 0.0 0.5 0.9 Rapasaari 0.3 0.5 7.4 Länttä 0.2 0.5 5.2 Total Measured 0.5 0.5 13.5 Indicated Syväjärvi 0.4 0.5 10.7 Rapasaari 1.1 0.4 25.4 Länttä 0.7 0.5 16.7 Outovesi 0.0 0.7 1.2 Emmes 0.9 0.6 27.6 Leviäkangas 0.2 0.5 4.6 Total Indicated 3.3 0.5 86.1 Inferred Syväjärvi 0.1 0.4 2.0 Rapasaari 1.3 0.4 29.3 Leviäkangas 0.2 0.4 5.3 Tuoreetsaaret 1.2 0.3 20.6 Total Inferred 2.8 0.4 57.1 Total Mineral Resource 6.7 0.4 156.7 Notes: 1. Mineral Resources are reported exclusive of Mineral Reserves derived from them. 2. The Mineral Resources are reported on an in-situ basis. 3. Mineral Resources are not Mineral Reserves and do not have demonstrated economic viability. 4. Mineral Resource are reported above an economic cut-off calculated for each deposit. 5. Note the Mineral Resource tabulation reports the % Li and not % Li2O. Contained Lithium is reported as Lithium Carbonate Equivalent (LCE) 6. All figures are rounded to reflect the relative accuracy of the estimates. 10.2.1 Conversions In line with industry practice, Li Mineral Resources and Mineral Reserves total metal content is quoted in Lithium Carbonate (Li2CO3) Equivalent (LCE), which is one of the final products produced in the Li mining value chain. LCE is derived from in-situ Li content by multiplying by a factor of 5.323. Li Hydroxide Monohydrate (LiOH.H2O) can be derived from LCE by dividing by a factor of 0.88. Li has been derived from Lithium Oxide (Li2O) by multiplying by a factor of 0.465. These conversion factors are shown in Table 10-6. Table 10-6: Lithium product conversion matrix Li Li2O Li2CO3 Li 1 2.153 5.323 Li2O 0.464 1 2.473 Li2CO3 0.188 0.404 1 LiOH.H2O 0.165 0.356 0.880 SRK Consulting – 592138 SSW Keliber TRS Page 121 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 10.3 Mineral Resource classification criteria and uncertainties [§229.601(b)(96)(iii)(B)(11)(iv)] The classification of the orebodies considers a combination of inputs to the confidence in the interpretation and estimates. The quality of the data is generally considered to be good, with accurate collar surveys, detailed logging and reasonable QA/QC support for the assays. For some of the deposits, supporting surface and underground mapping and geophysical surveys have also been undertaken. Where historical drilling has been undertaken by other companies in the past, Keliber has verified the data, including the re-assay of selected samples to confirm the analytical results. The style of mineralisation is similar between the deposits, and they are all in relatively close proximity. The continuity of the larger veins in all five of the deposits is demonstrated to be good during the geological modelling, with relatively uncomplicated morphology. At Rapasaari the number of veins is greater, and orientation of the veins is more complex, as can be observed in Figure 5.4 and Figure 10.2. The mineralisation is generally relatively uniformly distributed throughout the pegmatites. The variations in grade distribution seen are often related to Ms-pegmatite (often grading ~0.3% Li2O), and internal dilution. In addition, assessment of the variance of the Li2O in the composite datasets shows the variance to be low. The Coefficient of Variation for the domains rarely approaches or exceeds 1 and is typically in the range of 0.4 to 0.6 for the majority of the domains. This indicates that the grade variability within the domains is low, and therefore the consistency of the feed grade during mining is expected to be good The drill hole spacing is used as one of the primary discriminators of confidence in the deposits, with drill hole spacings of 40 m where a vein shows good continuity being acceptable for a Measured classification. Where the orebodies are observed to be more complex or taper, such as the deeper portions of the main pegmatite at Syväjärvi, a 40 m grid has been classified as Indicated. At Rapasaari, where the modelled orebodies are more complex, the larger veins drilled on a 40 m grid are classified as Measured, as is the 40 m drilled portion of the primary vein at Länttä. However, the smaller veins at Rapasaari drilled on a 40 m to 60 m grid are only classified as Indicated. At Emmes and Outovesi, the drilling density and geological continuity is only considered to be sufficient for classification as Indicated. Drilling density greater than 40 m, but less than 80 m, where there is reasonable size and continuity of the vein, is sufficient for classification as an Indicated Mineral Resource, and wider-spaced drilling, or where the modelled vein is small and intersected by only a few drill holes - therefore with less confidence in the continuity - is classified as Inferred Mineral Resources. The classification of the orebodies at Syväjärvi and Rapasaari are illustrated in Figure 10.8 and Figure 10.9, respectively. At Länttä the Measured classification is limited to the central portion of the orebodies, above an elevation of 195 m. SRK Consulting – 592138 SSW Keliber TRS Page 122 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Plan view of the Syväjärvi resource model with Mineral Resource classification Project No. 592138 Figure 10.8: Plan view of the Syväjärvi resource model with Mineral Resource classification SSW Keliber Lithium Project Isometric view looking northeast of the Rapasaari resource model with Mineral resource classification Project No. 592138 Figure 10.9: Isometric view looking northeast of the Rapasaari resource model with Mineral Resource classification SRK Consulting – 592138 SSW Keliber TRS Page 123 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 10.4 Reasonable Prospects of Economic Extraction [§229.601(b)(96)(iii)(B)(11)(iii) (vi) (vii)] The consideration of Reasonable Prospects for Eventual Economic Extraction (RPEE) is based on the calculation of cut-off grades based both on open pit (OP) optimisations undertaken for assessment of the potential for OP mining, and on an underground (UG) mining approach, which may be applied where an OP optimisation does not indicate a sufficiently-sized OP operation, or where the UG mining is considered more appropriate for optimising the ore body utilisation. Keliber is considering OP mining in four orebodies; Syväjärvi, Outovesi, Länttä, Rapasaari, as well as subsequent underground mining at Emmes and below some of the open pit operations. Tuoreetsaaret, and Leviäkangas have not been included in any mining studies and are thus not included in the Mineral Reserves. The engineering study work done for the proposed UG operations is to a scoping study (SS) level of accuracy, and hence excluded from the Mineral Reserves. The engineering study was completed before the declaration of Mineral Resources on the Tuoreetsaaret, and Leviäkangas deposits, and as such, these are not included in the study. For the OP mining in four orebodies; Syväjärvi, Rapasaari, Länttä; and Outovesi, engineering study work has been done to a Pre-Feasibility study level of accuracy. For Syväjärvi and Rapasaari, access to and from the mines has been selected on the basis of a combination of cost estimates, minimum traffic impacts on the inhabited areas and the vicinity of a Natura 2000 conservation area. The costs for improving existing roads and partly constructing new roads have been included in the cost estimates with detailed engineering in process. For the other operations (Tuoreetsaaret, Leviäkangas, Länttä and Outovesi), no engineering designs for access have been done to date. The proposed road connections to Länttä and Leviäkangas are separate from the other mine sites. The road connection will comprise partly an existing road and partly a new road. The proposed transport route for Outovesi is to build a connection road from Outovesi to Syväjärvi. Tuoreetsaaret is located in between Syväjärvi and Rapasaari and will share the infrastructure that is developed for these operations. The waste dumps for Syväjärvi, Outovesi, Länttä, and Rapasaari have been designed to a conceptual level with no surface water handling or access designs completed yet. A conventional drilling, blasting, truck and shovel operation has been selected and is a suitable OP mining method for Syväjärvi, Outovesi, Länttä, Rapasaari, Tuoreetsaaret and Leviäkangas. although for the latter two deposits no detailed mining studies have yet been undertaken. For the open pit optimisation process, which was used to determine the mineral resource pit shells, the OP mining costs vary between the mining areas and at depth. The average waste direct mining unit cost varies between USD2.67/t and USD5.31/t and the average ore direct mining unit cost varies between USD3.74/t and USD9.51/t, based on contractor quotes from the 2019 FS which has been increased by 25% and seem a reasonable assumption at this stage. The unit costs for OP mining (excluding processing) and accounting for the planned stripping ratios averages USD26/t ore mined. The processing cost varies between USD54.45/t and USD62.7/t per tonne of ore mined. Over the Life-of-mine (LoM) the maximum processing feed is 83.7 kt per month. It is planned to supplement OP mining production with UG mining, but the UG studies are currently at SS level and will not be included in the LoM plan or Mineral Reserves at this stage. Keliber is considering UG mining in three orebodies: two are UG extensions planned to follow the proposed OP operations in Rapasaari and Länttä; the third is a solely UG mine in Emmes. The three orebodies are similar in nature: steeply dipping and narrow and appear to have similar geotechnical characteristics. A bench-and-fill mining method has been selected to be the base-case, mined from the bottom of each orebody upwards in 20 m lifts, with fill being uncemented OP waste rock and waste development. Rapasaari and Länttä are proposed to be accessed via declines from the respective pits and, because the Emmes orebody is partially beneath a lake, the decline planned to access Emmes is developed from dry land on Åmudsbacken, a nearby property. The UG costs on which the Mineral Resource cut-off grade is based (USD21.2/t) are based on contractor quotes and would appear to be a reasonable assumption at this stage.
SRK Consulting – 592138 SSW Keliber TRS Page 124 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 The production rate for the UG mines is based on producing 12 500 tpa of LiOH. UG mining is planned to commence with Rapasaari in 2032, followed by Emmes in 2037 and Länttä in 2039. Figure 10.10 below shows the LoM production from the various mines. SSW Keliber Lithium Project Keliber_Economic_Model_v2.5.1_LoMvDFS21_SSW adjustments (ID 36372) RSa 18122022) Project No. 592138 Figure 10.10: LoM production The lithium hydroxide price, mining and processing costs considered in the cut off calculations are shown in Table 10-7. Table 10-7: Cut-off calculation parameters Cut off parameters Unit Open Pit Underground Price of LiOH.H2O USD/t 14 634 16 570 VARP (EUR100/t) USD/t 120 Mining USD/t 26.32 22.4 Development USD/t 16.3 Processing USD/t 54.19 54 Total cost USD/t 80.52 92.76 Cut-Off Li2O% 0.5 0.5 (Source: 11.08.01.04.01.03 Keliber_DFS_Volume_3_CH_13-17_February_01_2022_(final).pdf ) Note: EUR/USD exchange rate = 1.20 The defined Mineral Resources are all close to well developed modern access and service infrastructure. Kokkola has a modern port with all the facilities for overseas shipments and it is ice-free all year, as well as an airport and rail access. There are no infrastructural impediments to the development of the project. Power is readily available in the area, supplied by Kokkolan Energiaverkot Oy, and the power requirements have been adequately planned for the open pit operations, as well as for the potential underground SRK Consulting – 592138 SSW Keliber TRS Page 125 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 operations. Power and water supply have been considered in the engineering study, and all necessary logistics have been considered. At present there do not appear to be any environmental or permitting issues that will preclude the declaration of Mineral Resources or Mineral Reserves. While the time required for the authorities to process applications is uncertain and may defer project development if these applications are delayed, there is a reasonable expectation that all the required permits can be awarded. Keliber are actively managing the permitting and tenure processes. Keliber is completing a legal due diligence exercise through their legal advisors (Hans Snellman of Stockholm and Helsinki) to understand the permitting risks. The resolution of this risk is not required for the declaration of Mineral Resources. Metallurgical test work is at an advanced stage, and there are reasonable expectations that the selected processing route will perform within the defined parameters and achieve the expected recoveries. Keliber undertook an update of their TEM during 2022 to reflect the impact of the atypical inflation in both opex and capex, a consequence of the inflation in the macroeconomic environment. Despite the negative impact on costs, positive price movements have more than offset the higher costs. It is noteworthy that the inclusion of lithium forecasts is relatively new. The December 2021 forecasts from UBS showed only four analysts forecasting only the lithium carbonate price. The UBS forecasts for 2022 shows a long-term price of USD 14 461 per tonne, 36% higher than the December 2021 forecast. Long-term lithium hydroxide prices are slightly higher than those for lithium carbonate with a long-term price of USD 15 195 per tonne. December 2022 included forecasts for lithium hydroxide and spodumene with between five and ten analysts forecasting each. There is considerable uncertainty associated with the lithium market given the rapid changes in supply and demand, but the assumptions used by the project are aligned with current forecasts. Given that there is potential for higher realised prices than those assumed for the cut-off calculations, which result in a cut off value of 0.5% Li2O, the cut off value calculated is considered reasonable for Mineral Resource reporting, and should the higher prices predicted by Standard and Poors for example be achieved, there is potential for decreasing the cut-off value. However, it is understood that there is limited upside currently to decreasing the cut-off as the lower feed grade could create technical challenges and make it difficult to meet throughput and quality targets. 10.5 Reconciliation of Mineral Resources Sibanye-Stillwater announced its acquisition of the stake in the Keliber Lithium Project in February 2021 and declared their maiden Mineral Resource estimates for the project at 31 December 2021. No mining has taken place since the initial declaration and the only change to the total Mineral Resources is the addition of the two new deposits (Tuoreetsaaret and Leviäkangas) which were added to the declared Mineral Resource during 2022. Together these two deposits added 1.9 Mt (1.6 Mt attributable to Sibanye- Stillwater) at 0.4% Li to Keliber’s total Mineral Resource base. However, a more significant change is to the Sibanye-Stillwater attributable portion of the Mineral Resources, due to the acquisition during 2022 of a further 58.36% in the operating company, Keliber through Sibanye-Stillwater's 100% owned Keliber Lithium (Pty) Ltd taking Sibanye-Stillwater's total ownership to 84.96%. The change in attributable Mineral Resources (before the inclusion of Tuoreetsaaret and Leviäkangas) amounts to 8.8 Mt at 0.5% Li. In total, the change in Sibanye-Stillwater's attributable Mineral Resource at Keliber is 10.4 Mt at 0.5% Li. The reconciliation between the 2021 and 2022 Mineral resource estimates is shown in Table 10-8. Note that this comparison is undertaken on the Mineral Resources inclusive of Mineral Reserves. The 2021 Mineral Resource declaration is the same on an inclusive and exclusive basis as no Mineral Reserves were declare by Sibanye-Stillwater at that time, but the 2022 Mineral Resources would reflect those in Table 10-5 if reported on an exclusive basis. Table 10-8: Keliber reconciliation between the 2022 and 2021 Mineral Resource Estimates Classification Mass (Mt) Li2O (%) LCE (kt) 2022 2021 2022 2021 2022 2021 Measured 3.7 1.1 0.5 0.5 106.4 33.3 Indicated 8 2.4 0.5 0.5 202.4 62.0 Inferred 2.8 0.4 0.4 0.4 57.2 9.8 Total Mineral Resource 14.5 4.0 0.5 0.5 366.1 105.1 SRK Consulting – 592138 SSW Keliber TRS Page 126 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 11 MINERAL RESERVE ESTIMATES [§229.601(b)(96)(iii)(B)(12) Keliber is considering open pit mining in four orebodies at Syväjärvi, Rapasaari, Länttä and Outovesi; a fifth, Emmes, will be only mined underground. The Rapasaari and Länttä operations are intended to have underground extensions once the open pit is mined out. The orebodies are similar in nature, steeply dipping and fairly narrow and appear to have similar geotechnical characteristics. Engineering study work has been done for the proposed open pit that SRK considers to be at PFS study level and the underground mines that SRK considers to be at SS level of accuracy. While some of the work is of sufficient detail and accuracy for a FS, the overall study accuracy is limited by the less detailed aspects, which in some cases are conceptual. The mine sites have no existing infrastructure and before production start-up, all necessary infrastructure must be developed. Basic engineering of the mine sites infrastructure has been prepared by Sweco Finland for the Syväjärvi area, by AFRY Finland for the Rapasaari area and by Destia Finland for the Emmes, Länttä and Outovesi sites. The Syväjärvi, Rapasaari and Päiväneva is connected to the public road by an upgrade gravel road that was constructed during 2022 from gravel material mined from the Syväjärvi open pit area. The information for this section has been sourced from: • Keliber_DFS_Volume_1 to _ExecutiveSummary_February_01_2022_(final) in PDF format Volume_1 to _7; and • Keliber_Economic_Model_v2.5.1_LoMvDFS21_SSW adjustments (ID 36372) RSa 18122022.xlsx 11.1 Procedure for the estimation of Mineral Reserves [§229.601(b)(96)(iii)(B)(12)(i)] 11.1.1 Open pit optimisation Open pit optimisation was used to evaluate the economic open pit sizes for the ore reserve statement. The resulting maximum sizes were used as a basis for the final engineering design of the open pit shapes. An additional geotechnical study was performed to evaluate the most suitable open pit overall slope angles (OSA) and design parameters. For Syväjärvi, Länttä and Outovesi, the open pit optimisation was performed using Whittle software (Version 4.5). Whittle calculates the cash flow and net present value (NPV) of the open pit using the Lerchs- Grossmann algorithm to generate a series of open pit shells. The optimisations for the three open pits were re-done in 2021 with minor changes to cost mining and processing costs. For Länttä and Outovesi the product was changed from Li2CO3 to LIOH.H2O. In both cases these adjustments did not make any significant change thus the pit designs were retained. For the Rapasaari deposit, the open pit optimisation was achieved using the Deswik GO software (Version 2021.1). Deswik GO calculates the discounted cumulative cash flow indicating the NPV of the open pit by using the Direct Block Scheduling algorithm. Each block is analysed individually in the algorithm to define the best target period. 11.1.2 Open pit optimisation parameters The optimisation parameters include the Mineral Resource estimation block model (Table 11-3), all necessary operational costs, time costs, selling and processing costs of the final concentrate. The input factors used in the optimisation process include (Table 11-1): • Overall slope angles; • Geological block model; • Mining costs including variation by mining bench height; • Mineral processing costs; • Mineral processing; • Mining dilution and losses; and • Product revenues. SRK Consulting – 592138 SSW Keliber TRS Page 127 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 The Mining Cost per mining bench for Syväjärvi, Länttä and Outovesi are displayed separately in Table 11-2 and was not adjusted to show the ore cost as adjusted for the closer Keliber Lithium Concentrator at Päiväneva which was previously planned to be constructed at Kaustinen. Table 11-1: Open pit optimisation input parameters Description Unit Rapasaari Syväjärvi Länttä and Outovesi Optimisation Year 2021 2019 2017-2018 Exchange Rate EUR/USD 1.21 1.1 1.1 Price (LiOH.H2O t) USD/t 14 128 Price (LiOH.H2O t) USD/t EUR/t 2022 13 450 11 116 2023 13 250 10 950 2024 15 000 12 397 2025 16 500 13 636 2026 15 300 12 645 2027 15 200 12 562 2028 15 100 12 479 2029 14 200 11 736 2030 14 800 12 231 Price (Li2CO3) EUR/t 9 918 Total Fees and Royalties EUR/t 1.69 Discount Rate % 8 8 8 Modifying Factors Dilution (Including Internal Waste) % 19.5 14.2 0 Mining Losses % 95 95 95 Cut -Off Grade % 0.4 0.5 0.5 Geotechnical Overall slope angle East Degrees 37º 49º Overall slope angle West Degrees 41º Overall slope angle East and other areas Degrees 47º 45º to 50º Mining Cost Waste Mining EUR/t 1.85 Ore Mining EUR/t 3.22 Additional Bench Costs Waste Mining EUR/t 0.19 0.17 0.17 Ore Mining EUR/t 0.11 0.17 0.17 Blasting EUR/t Waste Mining EUR/t 1.19 1.19 Ore Mining EUR/t 1.6 1.6 Ore loading and haulage per km EUR/t 1.54 1.54 Waste rock loading and haulage per km EUR/t 1.43 1.43 Ore loading to Kaustinen and first haulage kilometre EUR/t 1.25 1.25 Each additional 1 km of ore haulage to Kaustinen EUR/t 0.15 0.15 Additional cost to mine Fe-sulphide bearing mica schist EUR/t 3.5 0 Fixed Cost (Processing Labour) 4.8 Processing Costs EUR/t 45 51.5 57 Global Lithium Yield % 74.30% 74.50% Länttä % 67.10% Outovesi % 73.10%
SRK Consulting – 592138 SSW Keliber TRS Page 128 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Table 11-2: Mining operational costs by mining levels, 2017-2019 (processing plant then to be located in Kaustinen) Pit Distance to Kaustinen Depth Mining level Ore mining cost EUR/t Waste mining cost EUR/t Syväjärvi 17 20 55 7.69 2.79 Syväjärvi 17 40 35 7.86 2.96 Syväjärvi 17 60 15 8.03 3.13 Syväjärvi 17 80 -5 8.20 3.30 Syväjärvi 17 100 -25 8.37 3.47 Syväjärvi 17 120 -45 8.54 3.64 Syväjärvi 17 140 -65 8.71 3.81 Syväjärvi 17 160 -85 8.88 3.98 Länttä 25 20 115 8.89 2.79 Länttä 25 40 95 9.06 2.96 Länttä 25 60 75 9.23 3.13 Länttä 25 80 55 9.40 3.30 Länttä 25 100 35 9.57 3.47 Länttä 25 120 15 9.74 3.64 Länttä 25 140 -5 9.91 3.81 Outovesi 17 20 70 7.69 2.79 Outovesi 17 40 50 7.86 2.96 Outovesi 17 60 30 8.03 3.13 Outovesi 17 80 10 8.20 3.30 Outovesi 17 100 -10 8.37 3.47 Outovesi 17 120 -30 8.54 3.64 SRK Consulting – 592138 SSW Keliber TRS Page 129 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Table 11-3: Summarized block model properties Parameter X Y Z Syväjärvi Minimum coordinate 7061900 2490250 -90 Maximum coordinate 7062700 2490700 90 User block size 10 10 5 Minimum block size 5 5 2.5 Rotation degrees 0 0 0 Total Blocks 36458 Rapasaari Minimum coordinate 7059750 2491500 -200 Maximum coordinate 7061750 2493000 300 User block size 10 5 5 Minimum block size 2.5 1.25 1.25 Rotation degrees 0 0 0 Total Blocks 4420086 Länttä Minimum coordinate 7057700 2506900 -100 Maximum coordinate 7058400 2507450 125 User block size 10 5 5 Minimum block size 10 5 5 Rotation degrees 45 0 0 Total Blocks 19299 Outovesi Minimum coordinate 7066600 3338350 -25 Maximum coordinate 7067350 3338650 95 User block size 10 5 5 Minimum block size 10 5 5 Rotation degrees 30 0 0 Total Blocks 4274 11.1.3 Optimization results This chapter describes the analysis between the previously optimised open pits and 2021 re-analysis with new processing flow sheet and LiOH∙H2O -tonne price estimate and operative cost estimates. The reason for the check analysis is that the flow sheet, prices and costs have changed since the last optimisations, and it is necessary to analyse whether the previous open pit designs still match to the updated optimisation results. The designs and pit shells were compared, and tonnes and other main results were compared between cases. Analyses are carried out in a very simplified approach to ensure reasonable accuracy between the previous and updated optimisation. The same optimisation approach, using Whittle™ 4.5 software, has been used in the sensitivity analyses as in the previous open pit optimisations in 2017 - 2019. Optimisation has been carried out in the following open pits: • Syväjärvi, previously optimised in 2019; • Länttä, previously optimised in 2017; • Outovesi, previously optimised in 2017; and • Rapasaari open pit was re-optimised during this DFS study in 2021. SRK Consulting – 592138 SSW Keliber TRS Page 130 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 The updated results of the Syväjärvi, Länttä and Outovesi indicated that there was no need to change the open pit designs for these thus the previous designs were used. 11.1.3.1 Syväjärvi evaluation The Syväjärvi open pit was first optimised in 2017. The latest update to the open pit was in 2019. Also, an underground option was studied in 2019. Analysis for the underground option was to understand the economic potential of the mineralisation from underground operations below the open pit. The Syväjärvi open pit optimisation (2019) indicated a profitable and feasible open pit mining scenario with a good project value. The Syväjärvi open pit optimisation scenario at maximum revenue factor of 1 indicates 1.8 Mt of ore reserves at a strip ratio of 6.07. A 0.5% Li2O cut-off grade was used for the Syväjärvi open pit optimisation. This provides an average of 1.08% Li2O feed grade for the ore inside the optimised pit shell. 5% ore loss was used in the Syväjärvi optimisation. The optimised final pit size was 480 m (N-S), 220 m (E-W), and 120 m deep. The haulage ramp can be placed to the west and north wall of the open pit to allow maximum steepness for the east wall that is located next to the Heinävesi Lake. Syväjärvi 2021 re-evaluation The Syväjärvi and Rapasaari open pits are the main ore feed sources in the mining project. Thus, the analysis of how the Syväjärvi pit design matches the optimisation with new prices and costs were considered important. The check analysis of the Syväjärvi indicates that changes in the processing flow sheet and LiOH∙H2O-tonne average price estimate, processing costs and minor changes in the mining costs have no change to the open pit optimisation results. Small changes in the results are within the error margin and are explained by the open pit selection process. The NPV of the optimisation result increased by EUR14m (Table 11-4). Therefore, it is justified to use the 2019 open pit design in the mine scheduling, Ore Reserve estimation and the final cash flow analysis of this DFS Report in 2021. In the Syväjärvi analysis the following assumptions were made: • A cut-off grade of 0.5% Li2O remains the same as in 2017 and in 2019. Cut-off grade has a very minimal effect on the open pit size and geometry at Syväjärvi. • Processing cost is adjusted to 45 EUR/t of ore following re-evaluation in 2021. • Mining costs are adjusted to correspond to 2021 cost estimates and quotes from mining contractors. Table 11-4: Syväjärvi analysis results Optimisation year Tonnages to processing Tonnages to waste NPV (EURm) Average ore waste opex EUR/t Processing Opex EUR/ ore t Li2O- feed grade Price EUR LiOH.H2O /t Cut-off grade % 20191 2 549 395 13 618 708 402 -4.6 51 1.08 % 12 107 0.50 % 2021 2 559 957 14 232 188 416 -4.3 45 1.07 % 12 521 0.50 % Note: 1. Definitive Feasibility Study Report Volume 3 Chapter 13 to 17 inclusive February 28, 2019 11.1.3.2 Länttä evaluation The Länttä open pit optimisation scenario at a revenue factor below 1 indicates 0.4 Mt ore reserves at strip ratio of 5.6. The optimal pit shape was selected based on an assessment of the underground mine profitability in a separate evaluation. As a result of that assessment, the selected scenario foresees underground mining methods being utilised for the remaining ore beneath the open pit. The Final pit geometry is 360 m long (SE-NW), 140 m wide (NE-SW) and 84 m deep. A 0.5% Li2O cut-off grade was used for the Länttä open pit optimisation. This provides an average of 0.89% Li2O feed grade for the ore inside the optimised pit shell. A 5% ore loss was used in the Länttä optimisation. SRK Consulting – 592138 SSW Keliber TRS Page 131 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Länttä Evaluation The Länttä open pit was previously optimised in 2017 and the result was a combination of open pit and underground operations (Table 11-5). An open-pit only option was also considered suitable, but the waste rock amounts were considered too high regarding environmental aspects and permitting. The Länttä ore consists of two narrow parallel ore lenses. Mining of the lenses using open-pit operations only will generate high waste to ore ratio, even though the operations are considered profitable. Therefore, an open-pit and underground option were considered as the best option. In the 2021 analysis, the same approach was used, and the optimisation aimed to match the same open- pit shape as was previously generated. Numerical results were then compared. The NPV of the optimisation result increased by EUR28m. Based on the results it is recommended to use the 2017 open pit design for the Länttä Ore Reserve estimation. In the Länttä analysis the following assumptions were made: • Cut-off grade 0.5% Li2O remains the same as in 2017. • Processing cost is adjusted to 45 EUR/t of ore. • Mining costs remain the same as in 2017 due to transportation from the Länttä pit to the processing plant. • Li2CO3 price was used in the optimisation in 2017. There were no plans for a hydrometallurgical plant in 2017. LiOH.H2O was the process main product in 2021. LiOH.H2O has a different price than Li2CO3. Table 11-5: Länttä analysis results Optimisation year Tonnages to processing Tonnages to waste NPV (EURm) Average ore waste opex EUR/t Processing Opex EUR/ ore t Li2O- feed grade Price EUR LiOH.H2O t Price EUR Li2CO3 t Cut-off grade 20171 383 470 2 161 388 26.7 -4.08 57 0.89 % 9918 0.5 % 2021 385 417 2 164 222 55.1 -4.08 45 0.89 % 12521 0.5 % Notes: 1. Definitive Feasibility Study Report Volume 3 Chapter 13 to 17 inclusive February 28, 2019 11.1.3.3 Outovesi evaluation The Outovesi deposit is considered to be an open-pit only operation. Underground mining is not considered a viable option for the currently delineated Mineral Resource. The Outovesi open pit optimisation scenario at a revenue factor of 1 indicates 241 kt ore reserves at strip ratio of 7.8. The final pit geometry is 370 m long (SE-NW), 120 m wide (NE-SW) and 75 m deep. A 0.5% Li2O cut-off grade was used for the Outovesi open pit optimisation. This provides an average of 1.07% Li2O feed grade for the ore inside the optimised pit shell. 5% ore loss was used in the Outovesi optimisation. Outovesi re-evaluation In the previous optimisation, the Mineral Resource was less fully utilised using open pit mining and the 2017 price range (Table 11-6). Therefore, there was no change to the open pit size in the optimisation even though the price for the end product is higher in 2021. The NPV of the optimisation result increased by EUR11m. In the Outovesi analysis the following assumptions were made: • Cut-off grade 0.5% Li2O remains the same as in 2017; • Processing cost is adjusted to 45 EUR/t of ore; • Mining costs remain the same as in 2017 due to transportation from the Länttä pit to the processing plant; and
SRK Consulting – 592138 SSW Keliber TRS Page 132 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 • Li2CO3 price was used in the optimisation in 2017. There were no plans for a hydrometallurgical plant in 2017. Therefore, the end product of LiOH.H2O in 2021 and the end product price is significantly different. Table 11-6: Outovesi analysis results Optimisation year Tonnages to processing Tonnages to waste NPV (EURm) Average ore waste opex EUR/t Processing Opex EUR/ ore t Li2O- feed grade Price EUR LiOH.H2O t Price EUR Li2CO3 Cut-off grade 20171 241 372 1 876 611 23 -3.62 57 1.07 % 9918 0.5% 2021 242 021 1 886 207 44.3 -3.62 45 1.07 % 12521 0.5% 11.1.3.4 Rapasaari evaluation The Deswik.GO™ direct block scheduling optimisation process produces a series of nested pit shells based on revenue factors and cash flow expressed as production periods (years). The cash flow for each shell is calculated using the input selling prices and costs and thereafter provides an indication of the economic changes in the production schedule. The resulted pit shells are used later on in the open pit and underground design phase. The Direct Block Scheduling open pit optimisation is carried out in two phases: Phase 1: Pit shell by pit shell optimisation - “Best and worst case cash flow” options are compared to pit shape and phases: • Indicates maximum pit; • The best cash flow case is rarely practically feasible to be mined. Therefore, intermediate option between and best and worst cash flow are selected for the pit size; • After max pit evaluation mining phases are generated for further designs; and • Waste and corresponding ore mined in a similar time frame - high cash flows first. Best ores mined first. Practically never functional. Phase 2: Bench by bench optimisation - “intermediate to worst-case cash flow”: • Almost always practically feasible; • Indicates the realistic cash flow out of the selected max pit and mining phases; • Redefines mining schedule within and between mining pre-defined phases; and • Some waste is mined much earlier than the ore it uncovers – Cash flow is optimised according to the mining phases. Detailed mine planning (years to months) will even the waste mining amounts and improve cash flow. Open-pit shell selection criteria Two open pit shells were selected for more detailed analysis and strategic evaluation. The first option was to utilize only the open-pit (OP) mining method maximising open pit Ore Reserve. The second option was for maximising Mineral Resource and to reduce the amount of waste rock, therefore an open-pit and underground option (OP + UG) was studied. The OP + UG option was seen as a more Mineral Resource-efficient approach in previous studies of Rapasaari. • In the OP only option, only a minimal amount of the Mineral Resource is left outside the open pit geometry. That small Mineral Resource part was considered too small to be economically extracted using underground methods and was marked as a sterilised Resource; and • The OP + UG option was seen more Resource-efficient option as most of the Mineral Resource was able to be mined with slightly smaller open pit and technically and economically viable underground mining. SRK Consulting – 592138 SSW Keliber TRS Page 133 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 In the optimisation the revenue factors against pit sizes and the cash flow curve were analysed in order to indicate the maximum mine life and profitability. But in the combined OP + UG operation the open pit shell and cash flow selection criteria also took into consideration the underground mining plans and the possibility to minimize the waste rock mining. Following criteria have been used for the pit shell selection for the Keliber Project: • Rule 1. Maximise cash flow (NPV). Overruled by rule no.2 if the resulted open pit geometry is not practically feasible. The maximum allowed deduction in NPV (from maximum) is 10%. • Rule 2. Generate practically feasible open-pit geometries. • Rule 3. Maximise cash flow (NPV) with the selected underground mining design in combined operation. Rapasaari optimisation results, open-pit + underground option For the option to commence an underground mining operation alongside open pit mining a smaller optimisation shell (revenue factor=0.4-0.5) was selected. The Rapasaari open pit optimisation indicated feasible open pit mining operations and potential Ore Reserve that could be technically and economically mined: • 0.4 % Li2O-cut-off grade was used for the Rapasaari open pit optimisation. This provides an average of 1.00 % Li2O- Insitu grade for the ore inside the optimised pit shell; and • 5 % ore loss was used in the Rapasaari optimisation. The Rapasaari open-pit and underground optimisation scenario at optimum cash flow indicates 7.8 Mt Potential Ore Reserves from the open pit at a strip ratio of 6.5 The estimated NPV at 8% discount rate is EUR1 030m after bench phase scheduling, pre TAX and no CapEx and sustaining CapEx items included Table 11-7. The open-pit only option optimisation would allow production for 11 years, but optimal underground mine combined with open pits 11-12 years of production. This approach was selected for further design. The overall cost, revenue and the cash flow evaluation to select suitable operation period, cash flow and final open pit tonnes is seen in Figure 11.1. Table 11-7: The Rapasaari open pit optimisation results in the bench by bench schedule according to the open pit phases and Mineral Resource categories Phase Mineral Resource Category Ore (kt) Waste (kt) Strip Ratio Li2O% NPV at 8% Discount Rate (EURm) Production Years 1 Measured 457.1 12 352.6 4.7 1.17 481 Indicated 2 178.2 1.07 2 Measured - 13 051.0 6.7 - 268 Indicated 1 941.8 1.06 3 Measured 777.6 13 249.8 8.2 1.04 165 Indicated 839.4 0.94 4 Measured 22.7 12 444.4 7.7 0.86 116 Indicated 1 594.7 0.82 Total Measured 1 257.3 51 097.7 6.5 1.1 1 030 11 Indicated 6 554.1 1.0 Notes: 1. The resulting ore tonnes are open pit optimisation based tonnes. 2. NPV values are based on optimisation and do not include CapEX or Sustaining CapEX values. NPV per phase are indicative. SRK Consulting – 592138 SSW Keliber TRS Page 134 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Rapasaari pit-by-pit optimisation results Project No. 592138 Figure 11.1: Rapasaari pit-by-pit optimisation results The selected open-pit geometries at 0.4 and 0.5 revenue factors have minor differences. Although a small extension in the north part of the open pit was seen as a major difference between the selected pits (Figure 11.2). Based on the waste rock haulage requirements for the north part of the open pit an additional ramp was designed in the extension area. The optimised Rapasaari final open pit shell is presented in Figure 2-6. The optimised final pit shell size was 1 310 m (N-S), 480 m (E-W widest part) in and 170 m deep. The geometry of the resulted final open pit was smooth and easily suitable for 775 kt/a ore production. The selected pit shell also enables the later underground operation at Rapasaari. The design for the underground operation will at a later stage be incorporated in the Mineral Reserves once the more exploration drilling has been completed to ensure the optimal open pit size has been determined. SSW Keliber Lithium Project Rapasaari open pit geometry Project No. 592138 Figure 11.2: Rapasaari open pit geometry. (blue geometry presents the 10-year production; brown the 9-year production) SRK Consulting – 592138 SSW Keliber TRS Page 135 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 11.2 Open pit design Based on the open pit optimisation results and geotechnical guidance, the open pits were designed as shown in Figure 11.4 (Syväjärvi), Figure 11.5 (Rapasaari) Figure 11.6 (Länttä) and Figure 11.7 (Outovesi). 11.2.1 Open pit geotechnical design parameters At Rapasaari the geotechnical conditions are most understood of all the deposits. Compared to other deposits, Rapasaari has had the most geotechnical samples tested in the laboratory to determine the mechanical properties of the rock. Rapasaari geotechnical information includes orientation data of joints, bedding planes and other structures. Overall, the rock quality in the studied areas of the deposit indicate good quality, competent rock. During February and March 2021 hydrogeological field measurements were carried out in Rapasaari. Hydraulic conductivity of the till layer was measured with slug tests in nine groundwater observation wells. The hydraulic conductivity of the bedrock was investigated from five drill holes. Hydrogeological conditions at Syväjärvi, Länttä, Outovesi and Emmes were studied at conceptual level. 11.2.2 Mine design criteria This section details the parameters used in the open pit and underground mine design process for the Keliber pre-feasibility study. The Parameters were obtained by AFRY from the following sources: • Pöyry Finland Oy 2017. Preliminary slope design study; • of Syväjärvi, Rapasaari, Länttä and Outovesi deposits; • Pöyry Finland Oy, 2018. Rock mechanical investigation of the Syväjärvi and Rapasaari Li- deposits; • Pöyry Finland Oy, 2019. Rock mechanical investigation of the Länttä Li-deposit; • Pöyry Finland Oy, 2019. Rock mechanical investigation of the Emmes and Outovesi Li-deposits; • AFRY Finland Oy 2020. Keliber Rock mechanical simulation of Rapasaari mine 2020.pdf; • AFRY Finland Oy 2021. DFS_LOM_2021_22.9.2021.xlsx; • AFRY 2021 – Numerical Groundwater Flow Modelling – Rapasaari open pit and underground mine; • AFRY 2021 - Flow Logging and Other Hydrogeological Studies at Rapasaari Project Area in Kaustinen, Finland. Flow Logging in Drillholes RA-93, RA-145, RA-155, RA-189 and RA-291); • JK-Kaivossuunnittelu Oy Data. Sent 2021-8-23.zip; and • PL Mineral Reserve Services 2018. Emmes_2018_surpacdata.zip. The open pit slope parameters are tabled and illustrated in Figure 11.3 and Table 11-8.
SRK Consulting – 592138 SSW Keliber TRS Page 136 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Open-pit slope sections and naming according to AFRY. (Source: Keliber_DFS_Volume_3_CH_13- 17_February_01_2022_(final).pdf) Project No. 592138 Figure 11.3: Open pit slope sections and naming according to AFRY For this study, the ramp width was increased to between 15-30 m for all pits except for the Outovesi deposit which is anticipated to be a small scale operation and thus a narrower single lane ramp is justified. Multiple ramp widths have been used within the open pits (Table 11-8). This is to optimize the ore to waste stripping ratio. The haul truck used for the design was the Caterpillar 777G (nominal payload capacity of 90 tonnes), which has an overall operating width of 6.687 m. A 22 m ramp width allows for safe two-way traffic with a drain ditch and safety berms on both sides of the road. The final benches in the pit designs have been designed using single lane access which allows for the retrieval of extra ore at the base of the pits. SRK Consulting – 592138 SSW Keliber TRS Page 137 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Table 11-8: Recommended parameters for open pit designs Open-pit design parameters Syväjärvi Rapasaari Länttä Outovesi Bottom of pit design -15mams -50mams 80mams 10mams Top of pit design 76mams 90mams 117mams 80mams Minimum mining width Overall slope angle (OSA) West = 41° East= 49° West = 42–50° East= 38–45° West = 41° East= 49° Inter ramp angle (IRA) West = 56° East= 46° West = 48° East= 48° West = 56° East= 46° Batter angle West = 75° East= 65° West = 75° East= 75° West = 75° East= 75° Ramp gradient 1 in 10 Ramp width 22 m 15/ 20/ 25/ 30 m 16 m 12m Bench height 20 m (4X 5 m benches) Berm width 8 m 14m 8 m 8m 11.2.3 Syväjärvi The open pit design required different bench angles for the east and west walls. The east side of the pit was adjusted according to a very linear (schistose) rock type that had a foliation plane dip of 55° - 65°. The east side bench angle was set to 65° while the west side bench angle was set to 75°. The deposit dipping at 18° means high waste rock mining in the hanging wall side of the ore. Hence, it is recommended that the waste rock extraction is advanced well before the ore extraction at the same mining level. The Syväjärvi ore consists of a single relatively thick unit that provides easy ore accessibility from three parallel ore lenses, two below the main ore lens on the south side and one above on the north. 11.2.4 Rapasaari Open pit mine design was done by AFRY, and it is based on the optimized pit geometries and open pit phases presented in the referenced report. Open pit production is separated into the main pit, one smaller satellite open pit at the west side of the main pit, and another to the south pit area. The ramp in the main open pit runs northwards along the eastern wall and then switches back to south at the north side of the main pit. The last part of the ramp divides the main open pit into two sections as the ramp runs down from the middle part of the open pit to the pit bottom. The west satellite pit and south open pit area are accessed by a separate ramp. The west satellite pit was designed smaller than the optimized open pit shell as the pit shell geometry was very small, creating difficulties in designing a pit that could reach the pit shell bottom. Therefore, a shallower pit was designed, and the remaining mineralisation was considered as suitable for underground extraction. The main ramp is designed to be 25 - 30 metres wide to enable two-way traffic. The smaller satellite pits have narrower ramps. The Rapasaari open pit design was done by using a 75° batter angle for all open pit benches. The overburden removal angle was set to 20°. The open pit optimisation was carried out at 37º overall slope angle in the east area of the open pit. Therefore, the main ramp (south to north direction) can be adjusted to the east side (footwall) of the open pit with a switch back to the south. This will allow the design to match the optimized open pit shell. The open pit design is accompanied by an underground design to increase the mining of known Mineral Resources with less waste rock mining. SRK Consulting – 592138 SSW Keliber TRS Page 138 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Rapasaari Open Pit Phases The intermediate open pit phases were designed according to the optimized open pit phases. The intermediate phases are designed in two-year intervals for production years 3, 5 and 7 respectively. The designed intermediate phases are later used in the mine scheduling work to define a more accurate LoM. The LoM for the whole mining project includes other pits included in the mining project Syväjärvi, Länttä, Outovesi and Emmes respectively. • Rapasaari Phase 1 for 0 - 3 years production; o A starting point for Rapasaari operations. A starter pit to maximize cash flow with minimized waste rock mining; o Ore haulage is carried out using east and west ramps; o Waste rock haulage is carried out using the north ramp. Waste rock is hauled to the nearby north waste rock storage facility; o The west satellite pit will be excavated during this period; • Expansion to the north pit area has started. Ore is accessible at the surface levels in the north area. Rapasaari Phase 2 for 3 - 5 years production; o Ore haulage is carried out using east and west ramps; o Waste rock haulage is carried out using north and west ramps. Waste rock is hauled to the nearby northeast waste rock storage facility; • Expansion to the south pit area has started. Rapasaari Phase 3 for 5 - 7 years production; o Ore haulage utilises the east and west ramps; o Waste rock haulage utilises the north and west ramps. Waste rock is hauled to the nearby northeast waste rock storage facility; o The west satellite pit will be completed; • Expansion to the south pit area has started Rapasaari Phase 4 for 7 - 10 years production; and o Ore haulage utilises the east and south ramps. 11.2.5 Länttä Open pit and underground mine planning for Länttä has been done by PL Mineral Reserve Services. The Länttä open pit design was done using a 75° bench angle for the whole pit. The pit bottom level was set at +80 mamsl. The ramp was located to circle clockwise around the open pit, starting from the southwest corner. Access to the underground mine is designed to start at the northwest corner of the open pit at elevation +93 mamsl. At the bottom of the pit, the pit bottom access ramp width is narrowed to eight metres. The overburden slope angle was set to 20°. 11.2.6 Outovesi The Outovesi open pit design was done using a 75° bench angle for the whole pit. The ramp was located to circle the open pit, starting from the east. At the bottom of the pit, the pit bottom access ramp width is narrowed to eight metres. The overburden slope angle was set to 20°. SRK Consulting – 592138 SSW Keliber TRS Page 139 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Syväjärvi open pit mine Layout and Ore Reserves (Source: Sibanye 2022) Project No. 592138 Figure 11.4: Syväjärvi open pit mine layout and Ore Reserves (blue= Proven Reserves, green = Probable Reserves) SSW Keliber Lithium Project Rapasaari open pit mine layout and Ore Reserves (Source: Sibanye 2022) Project No. 592138 Figure 11.5: Rapasaari open pit mine layout and Ore Reserves (blue= Proven Reserves, green = Probable Reserves)
SRK Consulting – 592138 SSW Keliber TRS Page 140 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Länttä open Pit mine layout and Ore Reserves (Source: Sibanye 2022) Project No. 592138 Figure 11.6: Länttä open pit mine layout and Ore Reserves (blue= Proven Reserves, green = Probable Reserves) SSW Keliber Lithium Project Outovesi open pit mine layout and Ore Reserves (Source: Sibanye 2022) Project No. 592138 Figure 11.7: Outovesi open pit mine layout and Ore Reserves (blue= Proven Reserves, green = Probable Reserves) SRK Consulting – 592138 SSW Keliber TRS Page 141 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 11.2.7 Modifying Factors [§229.601(b)(96)(iii)(B)(12)(vi)] The mining losses account for ore that is lost (hauled to the waste rock storage facility or not mined) during selective ore mining. Mining dilution occurs during blasting and excavation processes where ore and waste material are mixed. The additional waste rock materials are not desirable, as low-grade ore or waste material adversely affect the output of the processing system. Mining dilution increases the quantity of ROM ore to be mined and simultaneously reduces the mill feed grade. Mining dilution is a sum of multiple factors, including: • The selected mining method in question; • Mining equipment type, size and minimum mining width; • Nature, extent and geometry of the ore body; and • Quality of managed grade control. The geological resource block model Li2O value includes the diluting effect of white and black waste rock inside the mining block, which is considered to be internal dilution. In the mineral resource to ore reserve conversion, external dilution was also applied. For all the open pit operations Ore losses of 5% and external dilution of 10% has been applied. Internal black rock is calculated into the block model in the Rapasaari and Syväjärvi deposits. For Länttä and Outovesi the following proportions of internal black rock are used: • Länttä: 17.4 % • Outovesi: 0 % The given percentages are estimated by Keliber, by investigating the drill core intersections. The amount of planned external dilution has been estimated by calculating the partial percentage of ore solids within the mined blocks into the block model. In the reserve conversion, the dilution and mined ore tonnes are calculated as follows: Mined Ore = In-situ Tonnes x Mining Recovery x (100 + Unplanned External Dilution) Black rock dilution, which can be reduced by using a sorter, is calculated with the following methodology: 𝐵𝑙𝑎𝑐𝑘 𝑅𝑜𝑐𝑘 𝐷𝑖𝑙𝑢𝑡𝑖𝑜𝑛 = 𝑇𝑜𝑡𝑎𝑙 𝐴𝑚𝑜𝑢𝑛𝑡 𝑜𝑓 𝐵𝑙𝑎𝑐𝑘 𝑅𝑜𝑐𝑘 𝑀𝑖𝑛𝑒 𝑂𝑟𝑒 11.2.8 Cut-off grade [§229.601(b)(96)(iii)(B)(12)(iii)] A cut-off grade of 0.5% Li2O was used in the open pit optimisation for Syväjärvi, Länttä and Outovesi and 0.4% Li2O cut-off was applied to Rapasaari. With the selected optimisation cut-off grades, the 0.8 - 1% Li2O-grade is reached in all optimised pit shells. For the reserve conversion, a cut-off of 0.40 % Li2O was used for the open-pit ores. The cut-off grade was estimated using break-even cost/profit estimation. The breakeven calculation indicated that the cut-off grade of 0.40 % is reasonable, illustrated in Figure 11.8, Figure 11.9, Figure 11.10 and Figure 11.11 for the different operations. SRK Consulting – 592138 SSW Keliber TRS Page 142 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Rapasaari - Breakeven calculation results Project No. 592138 Figure 11.8: Rapasaari - breakeven calculation results for Rapasaari. Profit/loss are for 7.015 Mt of ore. The breakeven value is reached at 0.27 % Li2O cut-off grade SSW Keliber Lithium Project Syväjärvi - breakeven calculation results Project No. 592138 Figure 11.9: Syväjärvi - breakeven calculation results for Syväjärvi. Profit/loss are for 7.015 Mt of ore. The breakeven value is reached at 0.27 % Li2O cut-off grade SRK Consulting – 592138 SSW Keliber TRS Page 143 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Länttä - breakeven calculation results Project No. 592138 Figure 11.10: Länttä - breakeven calculation results for Länttä. Profit/loss are for 7.015 Mt of ore. The breakeven value is reached at 0.27 % Li2O cut-off grade SSW Keliber Lithium Project Outovesi - breakeven calculation results Project No. 592138 Figure 11.11: Outovesi - breakeven calculation results for Outovesi. Profit/loss are for 7.015 Mt of ore. The breakeven value is reached at 0.27 % Li2O cut-off grade 11.3 Mineral Reserve estimates [§229.601(b)(96)(iii)(B)(12)(ii)] Sibanye-Stillwater announced on 28 November 2022, subsequent to securing an effective controlling interest of 84.96% in Keliber as announced on 3 October 2022, the approval of capital expenditure of EUR 588m for the Keliber Lithium Project, beginning with the construction of the Keliber Lithium Hydroxide Refinery at Kokkola. Based on the Project FS completed during February 2022 and updated in October 2022 confirmed the robust economics of the Keliber Lithium Project at hydroxide prices significantly lower
SRK Consulting – 592138 SSW Keliber TRS Page 144 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 than the average prevailing spot prices over the previous 12 months. The open pit Mineral Reserves for the Keliber operations are summarised in Table 11-9. The Mineral Reserves are reported as it mill feed, based on the modifying factors discussed in the previous sections and the attributable interest of Sibanye- Stillwater in Keliber. Table 11-9: Mineral Reserves for Keliber open pit operations as at 31 December 2022 Classification Deposit Mass (Mt) Li grade (%) LCE content (kt) Proven Syväjärvi 1.34 0.52 37.18 Rapasaari 1.82 0.46 44.06 Länttä 0.15 0.51 4.16 Total Proven 3.31 0.49 85.40 Probable Syväjärvi 0.46 0.42 10.32 Rapasaari 4.14 0.40 89.02 Länttä 0.09 0.47 2.12 Outovesi 0.21 0.61 6.72 Total Probable 4.89 0.42 108.18 Total Mineral Reserve 8.20 0.44 193.59 Notes: 1. Cut-off for open pit reserves 0.40% Li2O 2. Price EUR23 667/t LiOH.H2O 3. Measured Resources converted to Proven Reserves 4. Indicated Resources converted to Probable Reserves 5. No Inferred Resources included in the Mineral Reserve 6. The Rapasaari mining permit has been granted but is under appeal 11.3.1 Conversions In line with industry practice, Li Mineral Resources and Mineral Reserves total metal content is quoted in Lithium Carbonate (Li2CO3) Equivalent (LCE), which is one of the final products produced in the Li mining value chain. LCE is derived from in-situ Li content by multiplying by a factor of 5.323. Lithium Hydroxide Monohydrate (LiOH.H2O) can be derived from LCE by dividing by a factor of 0.88. Li has been derived from Lithium Oxide (Li2O) by multiplying by a factor of 0.465. These conversion factors are shown in Table 10-6. 11.3.2 Comments Sound mine design and scheduling processes were used to convert the Mineral Resources to Mineral Reserves. SRK Consulting – 592138 SSW Keliber TRS Page 145 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 12 MINING METHOD – OPEN PIT MINING [§229.601(b)(96)(iii)(B)(13) AFRY has selected conventional truck and shovel operation as the most suitable open-pit mining method for Syväjärvi and Outovesi. For Länttä and Rapasaari, open-pit mining is considered to be combined with underground operations in the future. The general layout of the mine sites is shown in Figure 14.1 (Länttä), Figure 14.2 (Rapasaari), Figure 14.3 (Syväjärvi), and Figure 14.4 (Outovesi). A truck and shovel operation refers to the use of large, generally rigid body, off-highway haul trucks being loaded with blasted rock by large shovels or excavators. This combination of mining equipment is a proven technology and is used in many open pit mines throughout the world. The key points of a truck and shovel operation are: • The truck and shovel combination is a known and proven mining method, capable of handling most rock types in Finland. Potential mining contractors have suitable equipment readily available; • The haulage and loading equipment can handle both free-dig and blasted material; • The blending of ore from multiple deposits if needed is simple compared to other mining methods; and • The ability to produce the total annual mining rates is anticipated. In-pit ramps and waste rock haul roads are designed for off-highway trucks with a payload of 90 t. For waste mining, the bench height can vary between 10 – 20 m. Waste rock maximum particle size is not limited. 12.1 Rock engineering [§229.601(b)(96)(iii)(B)(13)(i)] Geotechnical conditions vary across the different sites, with open pit reserves having higher geotechnical data confidence due to existing exposures and laboratory test work. In-fill drilling and the associated testwork should consider further focus on discontinuity strength parameters for further improved geotechnical understanding of site and project specific conditions. It is noted that geotechnical data gathering and modelling are a continuous process during project implementation and mining operations, with confidence in rock mass and structural conditions improving over time as mining continues. The geotechnical conditions at Rapasaari are the best understood of all the deposits. Compared with the other deposits, Rapasaari is the only site from where geotechnical samples were tested in the laboratory to determine the mechanical properties of the rock. Rapasaari geotechnical information includes orientation data of joints, bedding planes and other structures. Overall, the rock mass quality in the studied areas of the deposit indicates good quality, competent rock as evident from the competent drill core and from competent rock mass on the exposed excavations observed during the site visit. 12.1.1 Rock mass quality RQD and geological strength index (GSI) models have been done for Rapasaari and Syväjärvi deposits. RQD and the GSI models were done for Rapasaari and Syväjärvi deposits from the geology core logging. RQD, GSI and rock quality rating number (Q’) values determined from logging of lithological units were then calculated. A total of 38 resource drill holes (18 from the 21st century and 20 from 1960), that were spatially distributed within the Länttä site were geotechnically logged for Q’, joint number, joint roughness, and joint alteration number, during early 2020. Thereafter, GSI and RQD values were then calculated, and models were created for utilisation in the rock mechanics studies. No structural orientation data is available. Due to the paucity of geotechnical data at Outovesi, no detailed investigation into the potential influence of lithological structures on geotechnics/stability has been carried out. SRK Consulting – 592138 SSW Keliber TRS Page 146 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 12.1.2 Rock strength parameters Samples that were taken for laboratory geotechnical rock strength test work for the Keliber Lithium Project were from the deposits that are planned to be mined during the first years of the operation. Sampling that was reported to have been carried out the Keliber Lithium Project area include: • 42 samples taken from different lithologies from the Rapasaari site, (Hakala and Heine in 2016 and Hakala et al. in 2020), that were tested for uniaxial compressive strength (UCS); • 35 to 45 samples from Länttä site that were tested for UCS (Tea Niiranen and Eetu Jokela, 2020); and • 15 samples from Länttä site that were tested for Brazilian tensile strength. These were considered in the February 2022 Definitive Feasibility Study report. Each core sample specimen for UCS and indirect tensile tests (Brazilian) (BR) was prepared according to ISRM (2006) suggested methods. The suggested length was 2 - 3 drill core diameters and rock samples were split into five groups according to their rock type. Foliation parameters of recognized volcanic and sedimentary units were estimated. The location of the drill holes from where the samples that were considered for rock strength test work is confirmed for the Länttä site unlike at the Rapasaari site. While the test work done at the Rapasaari site utilises recognised tests with standard testing techniques, no joint shear strength values were available for review. In the hard rock areas, the joint shear strength is likely to dominate slope stability, along with major and intermediate-scale geological structures. Review of the available data and previous reports did not indicate whether laboratory test work for saprolites was carried out. Additionally, the 3D location for where the samples were collected on the Rapasaari site could not be verified; this has an influence on the slope design. There was no mention of the QA/QC procedures that were carried out on the results of laboratory test work by the CPs from previous reports. The intact rock strength and elastic properties for the Syväjärvi site were estimated as the mean values for specific rock types, which were inferred from those determined from Rapasaari due to their proximity to each other in comparison to other mining areas. The rock and discontinuity strength and rock mass quality parameters on the Outovesi deposit are not well defined and will require a more detailed sampling and testing campaign before commencement of operations. No oriented geotechnical drilling was done for any of the sites. The geotechnical logging was carried out on geology drill core. No detailed Q-rating assessment and structural characterisation was carried out. The available geotechnical data considered during the review, coupled with reported observations on exposed excavations during the site visit, determine that the level of understanding of the rock strength parameters and characterisation is regarded to be appropriate to define the geotechnical environment for the Syväjärvi and Rapasaari sites to PFS level. 12.1.3 In-situ stress measurements The data supplied reveal that there are no in-situ stress measurements on the Keliber Lithium Project site. The current stress fields considered were simulated from data inferred from adjacent projects and operations for benchmarking purposes based on estimates from the closest measurements the team were able to access. The World Stress Map (WSM) and measurements taken from Pyhäsalmi Mine were used to determine the in-situ stress field of the area in question and applied to the deposits, 12.2 Hydrogeology hydrology [§229.601(b)(96)(iii)(B)(7)(iii)] All the deposits are located within bedrock of volcanic and metamorphosed lithological units with low hydraulic conductivity. Higher hydraulic conductivities are associated with bedrock fracturing and faulting. RQD data analysis suggest the Rapasaari, Syväjärvi and Outovesi rock mass is more intensely fractured in the upper part (above 50 mamsl) and less so at depth. Fracturing seems to be more persistent with depth and there is greater intensity at Länttä than the other deposits. The overburden at all the ore deposit sites contains till and peat of varying thickness. SRK Consulting – 592138 SSW Keliber TRS Page 147 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Field hydraulic testing and water level observations completed thus far are concentrated on the Rapasaari and Syväjärvi mine sites. Limited water level measurements for the Outovesi and Länttä deposits were taken. Groundwater assessment for Outovesi and Länttä was only completed at a conceptual level and thus no parameters are available to inform mining. Further, site specific hydrogeological characterisation and assessment would be required for the Outovesi and Länttä deposits to meet licencing and FS requirements Slug testing to determine the hydraulic conductivity of the overburden till layer was carried out at Rapasaari and Syväjärvi. The results from the two sites are of the same order of magnitude with an average of 6.3 to 7.7 x 10-7 m/s, which is a relatively low hydraulic conductivity. The RQD data was used as a proxy for hydraulic conductivity, through establishing a correlation with the hydraulic conductivity measurements. The approach followed seems reasonable, although a clearer description of the methodology and derivation of parameters from flow logging and RQD is required. The water table is shallow and close to surface. Recharge from precipitation is assumed to be relatively high at 50% of precipitation. Most of the recharge is assumed to flow laterally in the topmost surficial overburden layer. The interaction between surface water bodies and the groundwater is unknown; however, it is clear that the overburden plays an important role in conveying recharge to local streams and lakes that are fed by groundwater. 12.2.1 Groundwater inflows The groundwater inflows into the various mines were estimated using a numerical groundwater model for Rapasaari and Syväjärvi and analytical equations for Outovesi, and Länttä (Table 12-1). The inflows are less than 710 m3/d (Table 12-1) and it must be considered in light of the relatively short mining durations planned for all areas besides Rapasaari. The reported relatively low rates of inflow should not pose a material challenge to mining. The estimates are, however, preliminary but seem reasonable if the hydraulic conductivity is as low as reported. These estimates, hydraulic conductivity and inflows, will need to be updated with site-specific hydrogeological data as this is obtained to meet licencing requirements. The inflows at Rapasaari, however, are expected to peak at approximately 2 035 m3/d for the pit and 390 m3/d for the underground operations and may pose a risk to mining. No mention in the current water management plans is made of an active dewatering scheme to manage these inflows. Active dewatering through, for example, dewatering wells located along the pit perimeter will be required. Not adequately providing and planning for such may cause delays and have a severe impact on mining progress and safety. For the Syväjärvi open pit a cut-off drain will limit the flow from the upstream catchment to the dewatered Syväjärvi Lake. An embankment will also be constructed to prevent flow between lakes and the water table will be maintained at a low level through active dewatering. The pore pressure distribution behind the highwall of the Rapasaari and Syväjärvi pits has been excluded from safety factor calculations. This could be an important factor, particularly in the overburden, given the modelled tight cone of drawdown around the pits. Table 12-1: Summary of groundwater inflows per deposit Deposit LoM Open Pit Depth Inflows (m3/d) Drawdown Peak Pit Underground Rapasaari 14 (yr 0 to 14) 130m (-40 mrsl) ~ 2 035 at year 2.7 ~390 Limited drawdown, extends to the edge of Vionneva Natura. Syväjärvi 4 (yr 0 to 4) 100m (-5 mrsl) ~710 No UG working Few hundred meters from pit Outovesi 1 (yr 13 to 14) 75m (+10 mrsl) 640 No UG working Radius of drawdown c. 343 Länttä 3 (yr 13-16) 42m (+80 mrsl) 424 216 Radius of drawdown c. 270 for pit 12.2.2 Water quality The below is summarised from the Keliber Water Management Plan (Afry, 2021).
SRK Consulting – 592138 SSW Keliber TRS Page 148 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Generally, the different waters at Rapasaari-Päiväneva are slightly saline and mostly also slightly alkaline. Alkali and alkaline earth metals and aluminium are the cations present in highest concentrations. Sulphate, chloride, and silicate are the main anions. Rock dump and TSF source terms for the Rapasaari-Päiväneva area were determined through laboratory leach testing and modelling. In developing a mine-wide water management plan, loading to discharge streams was considered for the mine operation phase. Post closure, waste rock, pyrite-containing waste rock, flotation tailings (pre and post flush-off situations), pre-float tailings, and pit lake overflow loading was assessed. Nutrient content (nitrogen and phosphorus) is a significant part of the Rapasaari-Päiväneva area water quality and load. The source of the nitrogen is ascribed to explosives and the phosphorus is believed to be from the mined rock. However, the source of phosphorus is not totally understood. Modelling of the loading associated with the mine-wide water balance reveals that iron and phosphorous may exceed environmental quality standard (EQS). The total salinity and nitrogen content is also a concern to the watercourse ecology. Based on the environmental impact assessment the Fe and P loading does not pose a risk to the watercourses. However, the modelling exercise suggests that treatment of the water is required to address the nitrogen levels. The pyrite-containing waste rock will be deposited separately from the non-pyrite waste. The pyrite- containing waste is acid-generating and the seepage from the pyrite-containing waste rock is expected to contain high levels of Fe, and increased concentrations of metals and metalloids, such as Cd, Co Ni and Zn. Other key water quality parameters in Rapasaari-Päiväneva area are arsenic, copper, and selenium. In the source term assessments, arsenic and copper appear only in small concentrations because of natural sorption in the waste facilities. They are, though, released in significant extent in sulphide oxidation. Similar water quality issues are expected for all the other mining sites, with high sulphide levels expected at the Outovesi waste rock dump and more acidity and sulphate oxidation products. It should be noted that the Water Management Study (Afry, 2021) indicated that there is uncertainty in the Syväjärvi mine site water quality estimates, due to the methodology used for determining water quality. 12.2.3 Water balance A detailed water balance was prepared for the Rapasaari – Päiväneva Complex as part of the water management study (Afry, 2021). The model considered groundwater and surface water and was run using several scenarios, including a climate change scenario. The model indicates that while freshwater make- up may be required for the first few years of operation, there will be a water surplus for the remaining years of the operation (i.e., there will be discharge from the site). The risk assessment in the water management plan also states that there might not be enough water to supply the process water requirements during all seasons, due to modelled data being used to quantify the Köyhäjoki River flow rate. Once mining plans are developed, the water balance should consider including active dewatering as an alternative, or in addition to, pumping from the pit. Only a high-level water balance is available for the Syväjärvi site. The Länttä and Outovesi mine sites lack site-wide water and load balance models. 12.3 Life-of-Mine production schedule [§229.601(b)(96)(iii)(B)(13)(ii) and (iii)] The production schedule has been developed monthly. Production scheduling was completed using Mine Sched-software. The Syväjärvi operation was limited to a 540 ktpa production rate due to the limitations set on the environmental permit. The excess capacity of the grinding and crushing was then utilised by mining ore from the Rapasaari open pit in campaign-style mining. No blending of material from different deposits was allowed. The Rapasaari open pit is scheduled to be mined with campaign style in the first three operational years. After the Syväjärvi deposit is fully mined out the Rapasaari deposit can be mined at full capacity. The Keliber Lithium Project operations targeted LiOH.H2O production of approximately 15ktpa in the LoM production schedule. The totals for the production schedule are summarised per operation in Table 12-2. With the contribution of Rapasaari open pit the biggest at 6.9 Mt and 0.9% Li2O. The total LoM runs for 16 years from 2025 until 2040. SRK Consulting – 592138 SSW Keliber TRS Page 149 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Table 12-2: Keliber Lithium Project production summary Site Total (Mt) Ore Production (Mt) Stripping Ratio Li2O (%) Life-of-mine Syväjärvi OP 12.45 2.08 5.00 1.068 Apr 2025 to July 2028 Rapasaari OP 63.49 6.88 8.23 0.901 Jun 2026 to Dec 2037 Länttä OP 2.09 0.29 6.33 0.886 Sep 2038 to Mar 2039 Outovesi OP 2.56 0.24 9.67 1.331 Apr 2039 to Feb 2040 Total 80.59 9.48 7.5 0.95 Apr 2025 to Nov 2041 The Syväjärvi OP has the lowest stripping ratio of with 10.4 Mt of waste to strip. While Rapasaari, the biggest OP has 57 Mt of waste to strip at a stripping ratio of 8.2. The Länttä and Outovesi OPs are small compared to the other two OPs with both having approximately 2 Mt of waste to strip. At this stage no Backfilling for the OPs has been scheduled. 12.3.1 Life-of-Mine scheduling The mine production schedule for the Keliber Lithium Project incorporates the pit and stope design. The objectives of the production schedule are to: • Achieve targeted annual production in terms of quantity and quality. • Determine pre-stripping requirements. • Develop a production schedule suitable for operating cost estimates for the DFS. 12.3.1.1 Scheduling parameters The key scheduling parameters for the production schedule were to: • Provide plant feed for LiOH.H2O production: • Minimum: 15 000 tpa; and • Maximum: 16 000 tpa. • Design capacity for: • Crushing: 930 000 tpa; and • Grinding: 815 000 tpa. • Nominal capacity for: • Crushing: 775 000 tpa; and • Grinding: 680 000 tpa. • Limit Syväjärvi ore production to 540 000 tpa, to comply with its environmental permit. • Provide ore for a six-month ramp-up period using crushing capacity as the limiting factor. o 1st month 40% capacity; o 2nd month 65% capacity; o 3rd month 80% capacity; o 4th month 90% capacity; o 5th month 95% capacity; o 6th month 100% capacity; • Minimize initial waste stripping; SRK Consulting – 592138 SSW Keliber TRS Page 150 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 • No ROM stockpile has been modelled; however, it has been assumed that it will be located next to the crusher to accommodate for the short-term differences between mine deliveries to the ROM pad and crusher production rate; • No ore stockpiles next to open pits are modelled. It was assumed that short term ore stay over in the pads does not have a meaningful effect on the annual production scenario; • No haulage was modelled; and • If minimum LiOH.H2O production was not reached, the scheduler could produce lower amount of end-product. 12.3.1.2 Total material movement The total ore and waste material movement from the deposits is shown in Figure 12.1 Ore movements by open pit mines are shown in Figure 12.2. Major findings are: • After ramp-up, the ore reserves are sufficient to provide 7 years of stable production. • The first seven years of production reach the targeted minimum LiOH.H2O production. • The limits of processing at the concentrator will influence on the LiOH.H2O production when ore grade is lower. • Waste rock stripping varies due to the run down and ramp-up of an open pit. • Relatively small open pit sizes exclude the use of mining pushbacks resulting in high waste stripping during start-up. SSW Keliber Lithium Project Annual LoM feed production schedule Project No. 592138 Figure 12.1: Annual LoM feed production schedule SRK Consulting – 592138 SSW Keliber TRS Page 151 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Annual LoM feed production schedule Project No. 592138 Figure 12.2: Annual LoM feed production schedule 12.3.1.3 Sulphide-bearing waste rock Syväjärvi and Rapasaari deposits contain sulphide-bearing mica schist as a waste rock. These waste rocks will be deposited in a separate waste rock storage facility. Figure 12.3 illustrates the yearly amounts of excavated waste rock that contains sulphur. SSW Keliber Lithium Project Sulphide-bearing side rock by deposit (Source: Keliber_Economic_Model_v2.5.1_LoMvDFS21_SSW adjustments (ID 36372) RSa 18122022.xlsx) Project No. 592138 Figure 12.3: Sulphide-bearing side rock by deposit
SRK Consulting – 592138 SSW Keliber TRS Page 152 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 12.3.2 Production parameters 12.3.2.1 Operational parameters for ore production Key design criteria for daily ore production are presented in Table 12-3. Table 12-3: Key design criteria for daily ore production Ore mining Unit Quantity Mining bench height m 5 Max rock size mm 700 Max truck payload t 75 Ore feed Min. ROM-pad capacity days 3 Jaw crusher capacity t/h 453 Fine crusher capacity t/h 114 Coarse ore stockpile quantity t 2 280 Coarse ore stockpile duration h 20 Fine ore stockpile quantity t 1 200 Fine ore stockpile duration h 12 Shifts per day 2 Working days per week 7 Crusher operating hours h/a 800 12.3.2.2 Operational parameters for waste mining In-pit ramps and waste rock haul roads are designed for off-highway trucks with a payload of 90 t. In waste mining, the bench height can vary between 10 – 20 m. Waste rock maximum particle size is not limited. 12.3.2.3 Operational concept Keliber has decided to appoint mining contractor for open pit mining operations. The open pit contractor shall be chosen after competitive bidding during the project construction phase, approximately during Q3/2023. The key responsibilities of Keliber and the mining contractor are described below. Keliber is responsible for the following tasks: • Permits; • Mine permit; • Environmental permit; • Planning; • Annual and monthly production plans; • Geological and geotechnical studies; • Open-pit design and mine planning; • Preparatory measures (Client can appoint mining contractor for preparatory measures and pre- strip mining in order to obtain construction material, waste rock, for construction purposes); • Overburden removal; • Haul road construction (external pit); • Waste storage pads; • ROM pad and primary crusher; • Pad areas for social premises, maintenance, and storage areas (doesn’t include special structures for chemical storage); • Mine production; • General lighting (external pit); • Electricity distribution for maintenance facilities and social premises and open pit dewatering; SRK Consulting – 592138 SSW Keliber TRS Page 153 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 • Potable water distribution; • Jaw crusher operation; • Water management (external pit); and • Grade control, blast hole sampling and infill drilling. The open-pit contract includes all works of drilling, blasting, loading, hauling and all related ancillary works at the Syväjärvi and Rapasaari open pits. For Länttä and Outovesi open pits, a separate contract with a mining contractor will be made closer to their operation start-up. Mining contractor key tasks are the following: • Mine site environment, health, and safety (EHS) duties; • Site mobilization and demobilization; • All permits required by the service; • Maintenance and personnel facilities; • Drilling; • Charging and blasting; • Loading; • Ore; • Waste rock; • Sulphuric waste rock; • Hauling; • Ore; • Tipping to crusher feeder; • Tipping to ROM pad; • Waste to waste rock storage facility; • Sulphuric waste to separate waste rock storage facility; • Waste rock storage management, and filling according to plan; • Pit drainage and dewatering to client’s pipeline on the surface; • Preparation of the final pit walls and ramps according to the mine plan; • Pit wall scaling; • Haul road maintenance and dust control; • Handling and storage facilities including all required permits for: o Chemicals; o Explosives; o Fuel; and o Lubricants. 12.3.2.4 Operating hours The mine operating hours have been calculated on 350 production days per year. The open pit operation will be 24 hours per day, seven days a week, working on two 12-hour shifts. It is assumed that 15 days of production will be lost per year, due to bad weather and breakdowns. Additionally, one hour per shift will be lost due to mealtimes and breaks. These are common operating hours in Finland in remote locations. 12.3.2.5 Pre-production activities Key activities requiring completion before the start of mining are listed below. • Engineering and procurement; SRK Consulting – 592138 SSW Keliber TRS Page 154 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 • Detailed pit and mine site design; • The final tender process for construction work ; • The tender process for open pit mining contract; • Construction; • Access roads to sites; • Electricity distribution; • Water management (as specified in the environmental permit application and permit decisions); • Surface water management, perimeter drains and embankments; • Treatment for impacted runoff (sedimentation ponds and wetlands); • Pump stations and pipelines to the concentrator plant; • Waste rock storage facility pad preparation; • Haul road construction; • Overburden removal; and • Offices, maintenance and storage facilities (Mining contractor). Once overburden has been removed and the rock surface has been cleaned, waste rock mining can be started. Pre-production waste rock mining enables the first ore production blasts for the outcropping ore to be mined according to the production schedule. Construction material for haul roads and storage facilities is also obtained. The general layout for pre-production waste rock mining and the first ore production blast is shown in Figure 12.4. SSW Keliber Lithium Project Pre-production waste rock mining and first ore production blast Project No. 592138 Figure 12.4: Pre-production waste rock mining and first ore production blast Overburden removal will be separately contracted and sequenced to suit the mine production plans. Initial stripping cost is based on quotations acquired from contractors. Organic and inorganic soil materials are to be stored in separate areas to allow re-use during site rehabilitation. At Syväjärvi, lake sediments are to be stored in separate engineered storage. Moraine SRK Consulting – 592138 SSW Keliber TRS Page 155 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 material is to be utilized for embankment construction during Project development and production phases. The majority of the soil materials are however used in site closure. 12.3.3 Drilling and blasting The conceptual open pit bench drill design is presented in Figure 12.5. Open pit ore mining is based on a 5 to 10 m bench height. Waste rock can be mined in 10 to 20 m benches. Proposed drilling equipment in open pit mining for both ore and waste is a hydraulic, diesel-powered, self-propelled top-hammer drill rig. The proposed drill hole diameter for ore mining is 89 mm and for waste rock 89 -180 mm. The blasting pattern for ore will be selected to best match the maximum crusher feed size of 700 mm. Fragmentation optimisation will be considered during pre-production activities. Common practice is that the explosives manufacturer provides a down the hole explosive charging service. The parameters for open pit bench drill and blast design are presented in Table 12-4. The design parameters for the ore drill design need to be optimized according to the ore vein width. For a narrow 5-more vein, the burden of 2.5 m and a spacing of 2.7 m needs to be decreased. The specific drill pattern will be evaluated in the detailed production phase design. Table 12-4: Recommended parameters for open pit bench drill design Parameter Unit Ore Waste Buffer Pre-split Hole diameter mm 89 89-180 89 89 Burden m 2.5 2.5-3.1 1.25-1.5 2-2.5 Spacing m 2.7 2.7-5 1.35-2.5 1 Stemming m 2 3 0.7-1 2-3 Bench height m 5-10 10-20 5-10 5-11 Sub-drill m 0.75 1.5 0 0.75-11.5 Hole length m 5.75 11.5 2-4 5.75-11.5 The mining contractor will be responsible for the use and storage of the explosives, primers, and detonators. The explosives can be contracted as an in-the-hole service. The mining contractor will be required to perform test blasts for the open pit to optimize rock fragmentation according to requirements. Specific drill and blast designs will be developed by the mining contractor on site, according to local rock conditions and approved by Keliber engineers. The blasting sequence for open pit bench drill design is presented in Figure 12.6. The blasting sequence is a V-shaped sequence where the open face is at the bottom of the diagram. Presplit holes ensure a clean final pit wall with minor damage to the host rock.
SRK Consulting – 592138 SSW Keliber TRS Page 156 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Conceptual open pit bench drill design Project No. 592138 Figure 12.5: Conceptual open pit bench drill design SSW Keliber Lithium Project Blasting sequence for open pit bench drill design Project No. 592138 Figure 12.6: Blasting sequence for open pit bench drill design 12.3.4 Loading and hauling For open pit mining, the ore will be loaded onto off-highway trucks with a 72 t hydraulic excavator with a bucket capacity of 3.3 m3 and waste rock will be loaded with a 140 t hydraulic excavator with a bucket capacity of 8.1 m3. Truck size (payload) for ore is 75 t (Cat 775G) and waste rock 90 t (Cat 777G). Ore and waste can be visually identified due to the colour difference of the materials which is beneficial for selective loading and reduces waste dilution and ore loss. SRK Consulting – 592138 SSW Keliber TRS Page 157 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 12.3.4.1 Haul road design and maintenance The typical cross-sections of the external pit ore and waste rock haul roads are presented in Figure 12.7. Depending on the ground conditions, e.g. thickness of peat, the haulage road design is slightly altered as shown in Figure 12.8. The designs are based on equipment supplier recommendations and include safety berms on each side of the road to increase operational safety. The external pit haulage road design is the same for hauling ore and hauling waste rock. The typical cross-sections for the in-pit ramp designs are presented in Figure 12.9, Figure 12.10, Figure 12.11, and Figure 12.12. These designs are for 15 m, 20 m, 25 m, and 30 m ramp widths. SRK Consulting – 592138 SSW Keliber TRS Page 158 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project External pit ore and waste rock haulage road design with CAT 777G space requirements (peat layer ≤1 m) Project No. 592138 Figure 12.7: External pit ore and waste rock haulage road design with CAT 777G space requirements (peat layer ≤1 m) SRK Consulting – 592138 SSW Keliber TRS Page 159 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project External pit ore and waste rock haulage road design with CAT 777G space requirements (peat layer ≤1 m) Project No. 592138 Figure 12.8: External pit ore and waste rock haulage road design with CAT 777G space requirements (peat layer >1 m)
SRK Consulting – 592138 SSW Keliber TRS Page 160 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project In-pit ramp configuration for 15 m ramp width Project No. 592138 Figure 12.9: In-pit ramp configuration for 15 m ramp width SSW Keliber Lithium Project In-pit ramp configuration for 20 m ramp width Project No. 592138 Figure 12.10: In-pit ramp configuration for 20 m ramp width SRK Consulting – 592138 SSW Keliber TRS Page 161 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project In-pit ramp configuration for 25 m ramp width Project No. 592138 Figure 12.11: In-pit ramp configuration for 25 m ramp width SSW Keliber Lithium Project In-pit ramp configuration for 30 m ramp width Project No. 592138 Figure 12.12: In-pit ramp configuration for 30 m ramp width Road maintenance is included in the open-pit mining contract. It includes the following: • Addition/replacement of wearing course material including procurement; • Removal of snow; • Anti-skid; and • Dusting prevention (water trucks). SRK Consulting – 592138 SSW Keliber TRS Page 162 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 12.3.5 Grade control Successful grade control is a key factor in profitable mining operations because the mining Mineral Reserve is limited in nature. Grade control is also needed to help the processing plant work more efficiently as it is beneficial to have the feed grade to the process as close to the plan as possible. In open pit mines, grade control is performed daily and is an integral part of the mining operation. Grade control is commonly based on samples taken from production blast holes and geological mapping of the open pit. Grade control should be viewed as a process that consists of at least three basic aspects; data collection, grade control modelling and ore/waste boundaries; and operational procedures. Data informing the grade control model will be collected through geological mapping of the open pit and updating the geological models which are then used in production hole design. From the production holes, the drilled material is analysed, and a final decision is made on which holes are blasted as ore/waste. After blasting the bench, a grade-control geologist/mine geologist determines the boundaries of ore and waste and delivers loading instructions to the excavator operator. GPS- markers and trackers can also be utilized to monitor the movement of blasted material. 12.3.6 Primary crusher feed and ROM pad storage Primary crusher feed is the battery limit between mining and concentrator plant departments. Jaw crusher capacity is dependent on the maximum particle size of 700 mm and therefore the crusher has approximately four times higher design capacity than the fine crushing stages. To reduce the size of the primarily crushed ore stockpile, the primary crusher will be operated in two 8-hour shifts, seven days/week. The average primary crushing flow rate of 160 tph is slightly over two truckloads per hour which does not support a continuous ore loading and hauling operation. Potential mining contractors have proposed that the most economical ore production scenario is to run the pit mining operation in an 8-hour day shift, 5 days per week with a sufficiently high capacity to meet weekly production requirements and feed the crusher from the ROM pad during the second shift and weekends. Therefore, during the day shift, the ore is either directly tipped to the jaw crusher by haul trucks or stored on a ROM pad. During the second shift and weekends, the ore is fed to the primary crusher with a front-end loader from the ROM pad storage. ROM pad and crushed ore storage must have a minimum capacity of approximately three days ore production to cover production during weekends. The current costing basis is that 50 % of the ore will be directly tipped to primary crushing and 50 % fed with a front-end loader, which has an extra cost effect. 12.3.7 Waste rock storage facilities The Syväjärvi open pit will be the main source of construction rock material (blasted rock and crushed aggregates) during the project development phase. Therefore, waste rock mining will commence at the beginning of project construction. Some 500 000 t of waste will be mined for construction purposes during project development. During production, small amounts of waste rock will be transported to tailings dam raises or crushed for road maintenance. The balance of mined waste rock will be hauled to separate waste rock storage facilities (WRSFs) located in the vicinity of each pit. Material will be transported by off-highway trucks to a flat surface and pushed to a bench with a crawler-based dozer. This improves the safety of the work and stability of the waste rock storage. The final slope angle of the waste rock storage facilities will be 1:3 (vertical: horizontal) and the maximum height approximately 60 m to allow reasonable rehabilitation during closure. At Rapasaari, the WRSF will be divided into two to three sections which will be filled in phases and continuously rehabilitated (Figure 12.13). Due to the short mine life, this is not feasible at the other mine sites. SRK Consulting – 592138 SSW Keliber TRS Page 163 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Principal cross-section of the waste rock storage facility at Rapasaari Project No. 592138 Figure 12.13: Principal cross-section of the waste rock storage facility at Rapasaari The majority of waste rock is inert and environmentally benign, and the WRSF do not require a separate engineered liner system. Runoff from the WRSFs will be collected using natural elevation and perimeter ditches surrounding the areas. A minor amount of waste rock contains environmentally elevated sulfur content. This material will be placed in lined WRSF’s. The liner system consists of a bentonite mat and high-density polyethylene (HDPE) liner. The surface of the pad will be inclined towards collection ditches that are discharged to the collection pond. Water will then be pumped to the concentrator plant for treatment. All ditches and ponds are to be lined similar to the waste rock storage facility pad. Liners are protected against punctures with a geotextile or by a layer of fines and a prefill layer. 12.3.8 Mine dewatering and water management Mine site water management is presented in detail in the Water Management Plan. Water management and treatment systems will be constructed before other construction activities to reduce suspended solid releases to natural water catchments. During production, runoff from operational areas shall be collected and clean runoff from surrounding areas diverted around the operational areas with perimeter drains. At Syväjärvi, runoff from waste rock and soil storages, roads, and other constructed areas as well as pit drainage will be treated in sedimentation ponds and wetlands and discharged to the environment as stipulated by the Environmental Permit. Runoff from the sulfuric waste rock storage facility will be collected and pumped to the concentrator plant. At Rapasaari, runoff from all production areas will be pumped to the concentrator plant for treatment. Pit dewatering systems for all open pits consists of: • Mined pump sumps at the bottom of the pit; • Pump raft or fixed pump container; • Pipeline to surface; • Electricity supply; and • All open pits will implement the same dewatering strategy. The mining contractor will acquire and maintain the pump stations and in-pit pipelines and will be responsible for relocating the pump sump as mining advances deeper. Keliber will supply electricity cabling for the pump station and fixed pipelines on the surface.
SRK Consulting – 592138 SSW Keliber TRS Page 164 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Two natural ponds exist at the Syväjärvi open pit area. These ponds will be dewatered before production starts and the ponds will be maintained dry during the mine operation. Embankments will be constructed between the open pit and the remaining part of the ponds to control organic sediments and prevent water flow to the open pit. It should be noted that a free water table will not be allowed on the pond side during operation. 12.3.9 Explosives, fuel supply and storages Explosives and fuel supply for mining will be included in the mining contracts. Fuel storage tanks and refuelling stations are located at the contractor’s maintenance facility area. Crawler excavators will be refueled in the open pit by a fuel truck. Fuel will be stored in double-wall above ground steel storage tanks with an emergency basin. The refueling area will be a concrete foundation with an impermeable liner. Water and potential spillages are to be collected and treated in solids and oil separation chambers. The fueling area will be constructed according to standard SFS 3352:2014/A1:2020 – Service station for flammable liquids. Separate explosives storage areas with adequate safety distances have been reserved in each mine site layout. Explosives supply to the site and storing activities at the site are most likely part of the explosives manufacturer’s service. Storages will be constructed following the best industrial practices and the following legislation: • Act on the safe handling and storage of dangerous chemicals and explosives (390/2005); • The government decree on safety requirements for the manufacture, handling, and storage of explosives (1101/2015); and • The government decree on the control of the manufacture and storage of explosives (819/2015). 12.3.10 Open pit fleet Potential mining contractors were requested to present the equipment fleet needed for mining operations at Rapasaari and Syväjärvi open pits. Table 16-23 presents the numbers for the main mining equipment by each responding contractor. Table 16-24 shows the full mining equipment list, annual schedule, and utilization rates per equipment by a typical contractor (Contractor A). The equipment requirements are for a 10-year contract period. The total quantity and yearly distribution of mining fleet proposed by contractors were cross checked against AFRY Finland’s mining fleet optimization calculations. AFRYS mine fleet optimization results were similar compared to contractor estimates. AFRY’s opinion is that the mining fleet requirements given by the contractors are sufficient and they are not overestimated. Proposed drilling equipment in open pit mining for both ore and waste is the Sandvik Ranger DX800 which is a hydraulic, diesel-powered, self-propelled top-hammer drill rig. Potential mining contractors were requested to present the equipment fleet needed for mining operations at Rapasaari and Syväjärvi open pits. Table 12-5 presents the numbers for the main mining equipment by each responding contractor. Table 12-6 shows the full mining equipment list, annual schedule, and utilisation rates per equipment by a typical contractor (Contractor A). The equipment requirements are for a 10-year contract period. Table 12-5: Open pit mining equipment requirements according to contractor quotes Site Total (Mt) Ore Production (Mt) Stripping Ratio Li2O (%) Average waste mining cost EUR/t Average ore mining cost EUR/t Syväjärvi OP 12.45 2.08 5.00 1.068 2.67 4.38 Rapasaari OP 63.49 6.88 8.23 0.901 2.89 3.73 Länttä OP 2.09 0.29 6.33 0.886 5.30 9.51 Outovesi OP 2.56 0.24 9.67 1.331 2.71 5.21 SRK Consulting – 592138 SSW Keliber TRS Page 165 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Table 12-6: Mining equipment requirements for Rapasaari and Syväjärvi open pits, including a schedule by Contractor A Equipment Model Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9 Y10 Drill rigs Ore Sandvik DX800 (d89mm) 1 1 1 1 1 1 1 1 1 1 Waste rock Sandvik DX800/DX900 (d89- 127mm) 2 2 2 2 2 2 2 2 2 2 Spare (for maintenance and repair) Sandvik DX800 (d89mm) 1 1 1 1 1 1 1 1 1 1 Loaders Ore CAT 374 (75t) 1 1 1 1 1 1 1 1 1 1 Waste rock CAT 6015B (150t) 1 1 1 1 1 1 1 1 1 1 Spare (for maintenance and repair) CAT 390 (90t) / Hit 1200 (120t) 1 1 1 1 1 1 1 1 1 1 Haul trucks Ore CAT 775 (65t) 4 4 4 5 3 3 4 4 4 4 Waste rock CAT 777G (100t) 2 3 3 3 3 3 4 4 4 4 Spare (for maintenance and repair) CAT 775 (65t) 1-2 1-2 1-2 1-2 1-2 1-2 1-2 1-2 1-2 1-2 CAT 777G (100t) 1 1 1 1 1 1 1 1 1-2 1-2 Auxiliary equipment Receive ore to ROM pad, feeding crusher Komatsu WA600 (55t) 1 1 1 1 1 1 1 1 1 1 Receive waste rock to CAT D8 / D9 (30t /45t) 1-2 1-2 1-2 1-2 1-2 1-2 1-2 1-2 1-2 1-2 WRSF Secondary breaking CAT 330 + hydraulic hammer (30t) 1 1 1 1 1 1 1 1 1 1 Scaling permanent rock walls CAT 345 + hydraulic hammer (60t) 1 1 1 1 1 1 1 1 1 1 Leading groundwater in the pit etc. CAT 345 (45t) 1 1 1 1 1 1 1 1 1 1 Pumps 2 2 4 4 4 4 6 6 8 8 Road maintenance Motor grader 1 1 1 1 1 1 1 1 1 1 Wheel loader 1 1 1 1 1 1 1 1 1 1 Utility truck 1 1 1 1 1 1 1 1 1 1 Fuel supply Fuel truck 1 1 1 1 1 1 1 1 1 1 Supporting machines for maintenance Sleipners, Telehandlers etc 3-5 3-5 3-5 3-5 3-5 3-5 3-5 3-5 3-5 3-5 Light vehicles 4x4 6-8 6-8 6-8 6-8 6-8 6-8 6-8 6-8 6-8 6-8 12.3.11 Manpower Although mining will be undertaken by contractors, Keliber will have its staff in the following positions to manage and monitor mining at the start of mining operations. The list below will be updated throughout the mining operations. ● 1 Mine manager; ● 1 Mine planning engineer; ● 2 Mine geologists; ● 1 Mine surveyor; ● 1 Mine supervisor; ● 1 Geo-technician; and ● 1 Technician. SRK Consulting – 592138 SSW Keliber TRS Page 166 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 12.3.12 Mining costs [SR4.3(vii), SR5.6(iii)] The Mining Costs for open pit mining has been based on the contractors quotes the resultant averages over the LoM are listed per operation in Table 12-7. The contractor costs have been increased form the 2019 FS by 25% to include cost escalation since then. Table 12-7: Mining cost per open pit mining operation Site Total (Mt) Ore Production (Mt) Stripping Ratio Li2O (%) Average waste mining cost EUR/t Average ore mining cost EUR/t Syväjärvi OP 12.45 2.08 5.00 1.068 2.67 4.38 Rapasaari OP 63.49 6.88 8.23 0.901 2.89 3.73 Länttä OP 2.09 0.29 6.33 0.886 5.30 9.51 Outovesi OP 2.56 0.24 9.67 1.331 2.71 5.21 SRK Consulting – 592138 SSW Keliber TRS Page 167 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 13 PROCESSING AND RECOVERY METHODS The lithium hydroxide production process is split between two locations. Mined ore will be beneficiated at the Päiväneva concentrator located near the Rapasaari mine. Flotation concentrate will be transported to the Keliber Lithium Hydroxide Refinery where lithium hydroxide monohydrate will be produced as final product. The selected overall flowsheet comprises a conventional spodumene concentrator which includes crushing, ore sorting, grinding and spodumene recovery by flotation. Flotation concentrate is calcined to convert alpha- spodumene to beta-spodumene. The converted spodumene concentrate will be processed via the patented Metso-Outotec soda pressure leach to produce lithium hydroxide monohydrate. 13.1 Concentrator throughput and design specifications [§229.601(b)(96)(iii)(B)(14)(ii)] Concentrator process design is based on the results of the test work described in the 2022 DFS. Metso Outotec has used the test work data as a basis to provide basic engineering for the spodumene concentrator. The concentrator is designed for a nominal ore throughput of 680 000 tpa and a design throughput of 815 000 tpa, with a head grade before ore sorting of 1.13% Li2O and 1.2% Li2O after ore sorting. The design basis for the spodumene concentrator is to produce a flotation concentrate containing 4.5% Li2O for the downstream lithium hydroxide production process. In the production phase the lithium oxide grade of the concentrate will be a process optimisation point depending on ruling economic factors. In this regard, test work and design has covered the concentrate grade range from 4.5 to 6.0% Li2O. Keliber test work programmes have revealed iron, arsenic and phosphate to be the main impurities of the spodumene flotation concentrate for the downstream process. The maximum levels have been indicated to be 2% for Fe2O3, 50 ppm for As and 0.4% for P2O5. Concentrate will be dewatered and filtered to have average moisture content of 10%. The indicated moisture level is the highest allowed moisture for the concentrate preheating phase. Gravity concentration to produce a Nb-Ta concentrate is not included in the flowsheet of the concentrator because it was found not to be economically feasible for Syväjärvi ore. However, the required space for a gravity circuit has been reserved within the concentrator building. This will allow for the production of a Nb-Ta gravity concentrate should it be economically feasible for the Länttä ore which has higher Nb and Ta head grades. 13.2 Process description - concentrator The flowsheet of the spodumene concentrator includes the following unit process operations: • ROM pad for short-term ore storage before feeding the primary crusher; • Material handling equipment to feed the blasted ore to the primary crusher by ore trucks or front-end- loader; • Primary crushed ore silo with 20 hours capacity; • Crushing to produce a crushed product size of 80% passing (P80) 12 mm; • Ore sorting to remove black waste rock and increase the lithium oxide grade of the concentrator ore feed; • Rod mill feed silo with 12 hours capacity at the design throughput rate of 100 tph; • Rod milling in open circuit. The 3.0 x 4.45 m EGL rod mill will be equipped with a 470 kW motor; • Ball milling in a closed circuit with hydrocyclones to produce P80 grind size of 150 μm to flotation feed. The 3.6 x 5.6 m EGL ball mill will be equipped with a 1100 kW motor; • Low intensity magnetic separator to remove process iron and magnetic gangue minerals before desliming; • Two-stage de-sliming before spodumene flotation. The first stage de-sliming cluster will include seven ten-inch hydrocyclones (five operating and two stand-by) and nine six-inch hydrocyclones in the second de-sliming stage (six operating and three stand-by);
SRK Consulting – 592138 SSW Keliber TRS Page 168 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 • Pre-flotation to reject apatite, micas and hornblende. Pre-flotation will be operated in reverse flotation mode, where flotation overflow is rejected and pumped to tailings handling; o Pre-flotation includes roughing and one-stage cleaning flotation. Rougher flotation includes four 20 m3 tank cells in series and cleaning includes two 1.5 m3 tank cells; • Rougher scavenger flotation (5 x 50 m3 tank cells) to produce spodumene rougher concentrate; • Four stage cleaning flotation (13 x 10 m3 tank cells) to produce final spodumene flotation concentrate; • Dewatering of final spodumene concentrate by thickening (13 m diameter) and a pressure filtration (PF 55/60 M15) to obtain final concentrate with a moisture content of 10%; • Reagent dosing system for the concentrator; • Tailings from the concentrator will be deposited in conventional tailing ponds; and • Tailings from the lithium hydroxide plant (analcime). A simplified block diagram of the concentrator is presented in Figure 12.1. SSW Keliber Lithium Project Päiväneva concentrator – simplified block flow diagram Project No. 592138 Figure 13.1: Päiväneva concentrator - simplified block flow diagram 13.2.1 Primary crushing and raw material storage Ore at a top size of 700 mm is fed from the ROM pad to the feed bin by a front-end loader or ore trucks. Ore is fed to the primary jaw crusher via a scalping screen. Undersize rocks will by-pass the crusher while oversize rocks are crushed. A rock breaker will be installed next to the jaw crusher to handle blockages in the jaw crusher. Primary crushing capacity will exceed downstream secondary crushing capacity as it is to be utilised only on day shift. Crusher feed will be measured and automatically controlled. Crusher product particle size is approximately 70 mm. The by-pass stream and crushed ore reports to a sacrificial conveyor equipped with a tramp iron magnetic separator and metal detector. Tramp metal is collected and recycled off-site. Crushed ore will report to a storage silo with 20 hours live capacity. The primary crushing building will be equipped with a floor pump for housekeeping purposes and a bridge crane and hoist for maintenance purposes. A centralised dedusting system will be installed for personnel safety and housekeeping purposes. Suction points will be mounted at rock transfer points. Dust laden air will be filtered, with the filter discharge being recycled to the process. SRK Consulting – 592138 SSW Keliber TRS Page 169 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 13.2.2 Ore sorting and secondary crushing The basic principle of ore sorting is shown in Figure 13.2. SSW Keliber Lithium Project Basic Ore Sorting Operating Principle Project No. 592138 Figure 13.2: Basic ore sorting operating principle Different sensor technologies can be incorporated into ore sorting including Colour (reflection, absorption, transmission), Laser (monochromatic reflection/absorption), Near infrared spectrometry (reflection, absorption), Electromagnetic (conductivity, permeability), Radiometric (radiation), X-Ray Fluoresence, X-Ray Transmission. X-Ray Transmission (XRT) is based on relative atomic density differences and has been selected based on test results. Primary crushed ore is fed to a double deck vibrating screen, which separates ore into three fractions. Oversize material of P80 approximately 80 mm is forwarded to the secondary crusher, with secondary crushed material being recycled to the double-deck screen. Material from the second screen plate is directed to the ore sorting separation screen. Oversize reports to a washing stage ahead of the coarse ore sorter, while undersize reports to a washing stage ahead of the fine ore sorter. Each ore sorter separates waste from ore in its respective size fraction. Rejected material is fed to a stockpile for transport out of the concentrator area, while accept material is combined and forwarded to tertiary crushing. The undersize fraction from the double-deck screen is directed to the fine bypass conveyor and is combined with tertiary crushed material. Crushing and sorting buildings will be equipped with a floor pump for housekeeping purposes and a bridge crane and hoist for maintenance purposes. A centralized dedusting system will be installed for personnel safety and housekeeping purposes. Suction points will be mounted at rock transfer points. Dust laden air will be filtered, with the filter discharge being recycled to the process. 13.2.3 Tertiary crushing Secondary crushed and sorted ore reports to a vibrating screen. The oversized material, P80 approximately 25mm, is directed to the tertiary crusher. Tertiary crusher discharge is circulated back to the sorting accept conveyor. Vibrating screen undersize, P80 12 mm, is conveyed to the mill feed silo. 13.2.4 Grinding and classification The grinding circuit includes a 3.0 m x 4.45 m rod mill fitted with a 470 kW motor and 3.6 m x 5.6 m ball mill fitted with 1100 kW motor. The rod mill is designed to process 83 tonnes/hour at 75% solids in open circuit ahead of secondary ball milling. The ball mill operates at 65% solids in closed circuit with cyclone and screens. Target solids content for classification is 50 wt %. SRK Consulting – 592138 SSW Keliber TRS Page 170 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 The cyclone battery comprises two operational and one stand-by cyclone. Cyclone overflow at target P80 particle size reports to the grinding product pump sump. Cyclone underflow is pumped to ultrafine screens (three operational and one stand-by). Screen undersize at target P80 of 150 μm flows by gravity to the grinding product pump sump with cyclone overflow. Oversize material from the screens reports to the ball mill. 13.2.5 Magnetic separation Final milled product is pumped to magnetic separation using a low intensity magnetic separator (LIMS) to avoid spodumene losses. The magnetic fraction that includes process iron and magnetic minerals will be pumped to a lined tailings pond together with pre-float concentrate. The non-magnetic faction is forwarded to desliming. 13.2.6 Desliming and pre-flotation Desliming consists of two pumps and desliming hydrocyclones installed in series. The non-magnetic stream from the magnetic separator is pumped to the first desliming hydrocyclone cluster, which consists of seven 10-inch hydrocyclones (five operational and two on stand-by). Primary cyclone underflow is directed to a pre-flotation conditioner. Primary cyclone overflow is pumped to the second desliming hydrocyclone bank, which consists of nine 6-inch hydrocyclones (six operational and three on stand-by). Secondary cyclone underflow is combined with primary cyclone underflow in the conditioner tank. Secondary cyclone overflow is pumped to the spodumene tailings pump sump. The combined desliming cyclone underflow is mixed in the first conditioner tank with sodium hydroxide for pH regulation to approximately pH 10 and then it is fed to the second conditioner. The purpose of pre-flotation is to decrease the amount of phosphorous in the final concentrate. Fatty acid is applied to the second conditioner tank. Slurry gravitates to the pre-flotation stage, with emulsifier being fed to the feed box. Pre-flotation includes rougher with four TC-20 tank cells in series and cleaner flotation with two OK- 1.5 in series. Combined underflows from the pre-float rougher and cleaner stages are pumped to the spodumene flotation feed thickener. The overflow from the cleaner flotation is pumped to a separate lined tailings storage facility. Solid’s content of the tailings is approximately 17% and the mass recovery 1% with apatite recovery 32%. 13.2.7 Flotation feed thickening Pre-float tailings is thickened to 60% solids in an 18 m thickener ahead of spodumene rougher flotation. Thickener underflow is pumped to rougher flotation via the attrition conditioner and the overflow is pumped to the water treatment plant and there to the process water tank. 13.2.8 Spodumene flotation Thickened spodumene flotation feed at 60% solids is pumped to an attrition conditioner. In the first conditioner pH is regulated with sulphuric acid, targeting a pH of 7. From the first conditioner, slurry is directed to the second conditioner where fatty acid is introduced to the slurry. Emulsifier is added to the slurry from the attrition conditioner as it flows to rougher flotation, which comprises one bank of five 50m³ rougher flotation cells. The combined concentrate from rougher flotation is pumped to the first cleaner flotation. Tailings is pumped to the tailings thickener. Spodumene cleaner flotation includes four stages. The first stage includes five 10 m³ cells, the second stage has three 10 m³ cells, the third stage has three 10 m³ cells and the fourth stage has two 10 m³ cells. The underflow of the first cleaner is pumped back to the flotation feed thickener. The overflow is pumped to second cleaner flotation. The concentrate from the second cleaner is pumped to the third cleaner flotation and tails flow back to the first cleaner via gravity. Concentrate from the third cleaner is pumped to the fourth cleaner flotation and tails flow back to the second cleaner via gravity. Concentrate from the fourth cleaner is pumped to the concentrate thickener and tails flow back to the third cleaner via gravity. 13.2.9 Tailings thickening Tailings from rougher flotation and desliming cyclones are pumped to the 12 m diameter tailing’s thickener. Thickener underflow at 60% solids is pumped to the tailings dam. The overflow is pumped to the water treatment plant and from there to the process water tank. SRK Consulting – 592138 SSW Keliber TRS Page 171 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 13.2.10 Concentrate thickening The final flotation concentrate is pumped to the 13 m diameter concentrate thickener. The overflow from the thickener is pumped to the water treatment plant and from there to the process water tank. The underflow at 60% solids is pumped to the concentrate filter feed tank by an underflow pump. 13.2.11 Concentrate filtration and concentrate storage Filter cake at 10% design moisture is dropped to cake discharge chutes after filtration and then conveyed to the concentrate stockpile. The filtrate pumped to the concentrate thickener feed box. The concentrate storage facility will provide sufficient material for two days (48 h) operation, providing a buffer between the concentrator and the chemical conversion plant. Spodumene concentrate will be loaded by a front- end loader and transported by truck to the receiving concentrate storage at the Keliber Lithium Hydroxide Refinery in Kokkola. 13.2.12 Particle size and on-stream slurry analysers Metso Outotec PSI 500 particle size analyser is an on-line size measurement system for mineral slurries. It is used in controlling wet mineral processes, primarily grinding, classification, re-grinding and thickening. Samples for particle size analyses are taken from the LIMS feed, the first desliming cyclone overflow and the second desliming cyclone overflow. Courier 8 is an on-stream slurry analyser that can measure element concentrations in slurries for up to 12 samples. It was designed for on-stream measurement of light elements and is suitable for Li measurements. Simultaneously up to 20 element concentrations and solids content can be measured from one sample. Samples for the element analyses are taken from the sample divider, pre-float tailings, spodumene flotation tailings, spodumene rougher flotation concentrate, spodumene first cleaner flotation tailings and final concentrate. Samples from slimes, whole pre-float concentrates stream and sampler whole magnetic fraction stream report to the multiplexer. Streams from rougher concentrate, first cleaner tailings and all the analysed streams are returned to the process by pump. Samples from the final concentrate will be pumped back to the concentrate pump sump. 13.3 Process design criteria - concentrator Key concentrator process design criteria are shown in Table 13-1. Table 13-1: Key process design criteria - concentrator Description Unit Value Plant design capacity tpa 815 000 tph 100 Ore moisture % 5 Head grade (run of mine ore) % Li2O 1.13 Head grade (after ore sorting) % Li2O 1.20 Lithium recovery % 88 Sorting and crushing availability % 85 Crushing circuit P80 mm 12 Concentrator availability % 93 Bond Abrasion index 0.4 Bond Crushing Work index (Syväjärvi ore) kWh/t 12.4 ± 1.9 Bond Rod Mill Work index (Syväjärvi ore) kWh/t 15.3 Bond Ball Mill Work index (Syväjärvi ore) kWh/t 18.9 De-sliming 1 cut size µm 30 De-sliming 2 cut size µm 7 Pre-float feed P80 µm 130 Pre-float slurry density % solids 30 Spodumene flotation feed P80 µm 150 Spodumene flotation slurry density % solids 30 Final spodumene flotation mass pull % 23.5 Final spodumene concentrate grade % Li2O 4.5 Final spodumene concentrate production tph 23.5
SRK Consulting – 592138 SSW Keliber TRS Page 172 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Bond rod mill index of Länttä ore was determined as 12.6 kWh/t and ball mill work index at 17.1 kWh/t. Bond rod and ball mill indexes are 15.3 kWh/t and 15.2 kWh/t for Rapasaari ore. The geo-metallurgical study showed that the grindability only varies a little between deposits and correlates with spodumene grade (higher spodumene grade means higher resistance for grinding). As the mineralogical differences between the deposits are small it was considered that grindability would be within these ranges in untested Emmes and Outovesi. 13.4 Requirements for energy, water and consumables [§229.601(b)(96)(iii)(B)(14)(iii)] The following services will be provided: • Flotation air • Plant and instrument air • Raw water • Process water • Sealing water • Warm water • Potable water • Fire water 13.4.1 Power In terms of the 2022 DFS Report, electric power to the Päiväneva concentrator will be supplied from a local distribution grid at Kaustinen owned and operated by a local utility company. At the supply end, the transmission cable will be connected to the 110 kV distribution grid through a 16 MVA main transformer. Power will be transmitted to the Päiväneva concentrator via a 33 kV underground transmission cable. At the Päiväneva site the external power supply will be connected to a 33 kV main distribution switchgear, from which the power will be further distributed to local process substations. The Päiväneva concentrator power requirements are estimated at 11 410 kW. 13.4.2 Raw water pumping and treatment A raw water pumping station will be constructed at the Köyhäjoki river for raw water pumping to the chemical raw water treatment plant. Raw water pump dimensioning is based on estimated flowrate of 150 m3/h. Raw water from Köyhäjoki river will be micro filtered and preheated to 10°C before being chemically treated with a precipitation chemical and pH-adjusted with NaOH. Preheated and chemically treated water will be pumped to three DynaSand contact filters for humus removal. Sludge handling includes a Lamella clarifier, sludge thickener and drying by sludge centrifuge. 13.4.3 Process water treatment The process water treatment plant consists of two similar, dissolved air flotation (DAF) units, which remove suspended solids and colloid material from liquid by means of air bubbles that attach to agglomerates and raise them to surface. The flotation basin is equipped with a surface sludge removal system. Sludge is removed by gravity. Clarified water will be pumped to the process water tank. 13.4.4 Pre-float water treatment The techniques applied to remove arsenic species include oxidation, coagulation-flocculation, flotation and pressure sand filtration. The first oxidation stage is done by a prefabricated bottom diffuser / aeration system ahead of an aerated coagulant tank. Common coagulants used for arsenic are iron salts. The precipitation of ferric arsenate is commonly done at pH 4 – 5. To ensure the stability of ferric arsenate, an excess amount of iron must be dosed compared to the amount of arsenic. After coagulation and flocculation, the suspended solids are removed by micro-flotation followed by pressure sand filtration as a final polishing stage. SRK Consulting – 592138 SSW Keliber TRS Page 173 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 13.4.5 Excess water treatment In the recycled water treatment plant, the equipment will be similar to the pre-float water treatment, with larger equipment sizes. 13.4.6 Potable water Potable water will be drawn from the municipal water system. 13.4.7 Fire water Fire water pumps will be located at the water treatment plant. Water from fresh water and process circulation ponds can be used as fire water. 13.4.8 On-line water management tool development for the concentrator Keliber has started development work for concentrator water management. The purpose of the management tool is to provide real time concentrator-wide water balance management, control and reporting including what-if scenarios. The tool will summarize real time weather data and on-line process data from the concentrator automation system to provide visualisation and simulation as well as reporting. 13.5 Concentrator reagents and consumables Table 13-2 summarises the reagents and consumables for the concentrator. Table 13-2: Concentrator reagents and consumables Description Unit Value Rod Mill Grinding Media Consumption g/t 593 Ball Mill Grinding Media Consumption g/t 690 Caustic Soda Consumption (NaOH) g/t 500 Sulphuric Acid Consumption (H2SO4) g/t 50 Rape Fatty Acid Consumption g/t 1 390 Emulsifier Consumption g/t 155 Flocculant Consumption g/t 80 13.6 Lithium hydroxide production plant throughput and design specifications [§229.601(b)(96)(iii)(B)(14)(ii)] [SR5.3(iii)] The Keliber Lithium Hydroxide Refinery at the KIP, Kokkola is designed with a feed capacity of 156 000 tpa of spodumene concentrate, which translates to an annual lithium hydroxide monohydrate production of 15 000 tonnes at 99.0% LiOH.H2O purity for the final product. A simplified block flow diagram of the Lithium Hydroxide Plant is shown in Figure 13.3. SRK Consulting – 592138 SSW Keliber TRS Page 174 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Simplified block flow diagram of the lithium hydroxide production plant Project No. 592138 Figure 13.3: Simplified block flow diagram of the lithium hydroxide production plant Key unit processes in the production of lithium hydroxide are summarised as follows: 13.6.1 Concentrate receipt The spodumene concentrate will be transported by truck to the Keliber Lithium Hydroxide Refinery located at the Kokkola Industrial Park (KIP) at Kokkola harbour. The capacity of the receiving concentrate storage facility is sufficient for two weeks of operation. The storage capacity will provide the flexibility to blend different concentrate qualities and to ensure stable operation for the downstream lithium hydroxide production process. The blending and homogenisation might be required to control the lithium oxide grade and levels of impurities in the feed to the lithium hydroxide plant. 13.6.2 Spodumene calcination (conversion) Alpha-spodumene is converted to beta-spodumene in a direct heated rotary kiln. The rotary kiln will be fired with LPG and operate at 970-1075 °C. A rotary cooler unit is used to cool the converted beta-spodumene down to between 80 and 90 °C before pulping with the circulating liquids - filtrate and wash water from the 1st stage (autoclave) residue filtration, in two agitated tanks in series. 13.6.3 Pressure leaching of beta-spodumene Primary leaching in soda leaching autoclave operating at a temperature of 215 °C and 20 - 22 bar gauge pressure. High pressure steam is used for maintaining the temperature. Beta-spodumene will be converted to Li2CO3 and analcime as a by-product according to the following equation: 2LiAlSi2O6(s) + Na2CO3 + 2H2O = Li2CO3(s) + 2NaAlSi2O6 H2O(s) SRK Consulting – 592138 SSW Keliber TRS Page 175 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Slurry from the autoclave is released by pressure difference into two-stage flashing. 13.6.4 Soda leach residue filtration Autoclave slurry solid/liquid separation with two parallel pressure filters. Soda leach residue consists mainly of solid analcime (NaAlSi2O6*H2O), Li2CO3, lithium carbonate, quartz and other gangue minerals. This is pulped with leach residue wash water and forwarded to LiOH conversion. Part of the filtrate is recycled for filter manifold flushing after the filling/filtration step. The manifold flushing stage pushes residual solids to the chambers and filtrate to the filtrate tank. Residual manifold flushing liquid is released from the pipeline to an agitation tank, from which the slurry is returned to the filter feed tank. Spent cloth wash waters are recycled to the cake wash tank. Part of the filtrate and wash water is fed back to calcine grinding and pulping. The rest of the water is fed to effluents, to control the leach circuit water balance. The amount of process bleed to effluent is greatly dependent on the lithium grade of the calcined beta-spodumene feed. The lower the Li2O grade, the higher the consumption of cake wash waters. 13.6.5 LiOH conversion Pulped soda leach slurry, lime slurry and wash waters from leach residue filtration are fed to conversion reactors. Conversion is done preferably below 30 °C to minimise solubilisation of aluminium and silica. Li2CO3 in soda leach solids reacts with Ca(OH)2 according to following reaction: Li2CO3(s) + Ca(OH)2(s) = 2Li+ + 2OH- + CaCO3. Only LiOH is water soluble, and the others are insoluble. 13.6.6 Leach residue filtration and handling After conversion leach, the slurry is fed to leach residue filters for solids-liquid separation using two parallel pressure filters. Filter cake consisting mainly of analcime, calcium carbonate, quartz and other gangue is discharged. Filtrate is fed through polishing filtration to ion exchange. Wash water is fed to Lime slurrying and 1st stage residue pulping. 13.6.7 Polishing filtration Feed from the secondary conversion is fed through a polishing filtration stage where suspended solids are removed from the lithium hydroxide solution. The polishing filtration is carried out in LSF type polishing filters. One will be in operation and one on stand-by. 13.6.8 Ion exchange Ion exchange is done in three fixed-bed columns connected in series for removal of elevated multi-elements e.g. Ca and Mg from the solution before LiOH crystallisation. The regeneration cycle starts with the pre-wash stage, where 2 M sodium hydroxide solution is fed to the column, mainly to displace most of the lithium bound to the resin with sodium ions. After pre-wash, follows the first displacement wash with demi water. A short backwash with demi water is done after the first displacement wash to backwash the resin bed and remove any air bubbles and possible channelling. Elution of the metals is done with excess 2 M hydrochloric acid solution. The resin functional groups are simultaneously converted to acid form. The acidic eluate stream, containing mainly calcium, sodium and potassium as chlorides is fed to effluent treatment. After a second displacement wash with demi water neutralisation of the resin to lithium form is done with process lithium hydroxide solution. After regeneration, the column is connected as the last column in the series. 13.6.9 Crystallisation of lithium hydroxide Lithium hydroxide is crystallised from the lithium hydroxide solution by means of pre-evaporation in a mechanical vapour recompression (MVR) falling film evaporator, followed by an MVR crystalliser. Lithium hydroxide LiOH*H2O is crystallised according to following reaction: Li+ + OH- + H2O = LiOH*H2O(s) Lithium hydroxide slurry from the crystallisation stage is fed to a centrifuge where solids are separated from the mother liquor and washed. Moist cake is dried in a fluidised bed dryer and packed into big bags for shipment to market.
SRK Consulting – 592138 SSW Keliber TRS Page 176 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Most of the mother liquid is circulated back to conversion in order to control the soluble concentration of Al, CO3 2- and Si in solution. A small portion of the mother liquor is fed to bleed treatment: carbonation and conversion. 13.6.10 Crystallisation bleed treatment Lithium in crystallisation bleed liquor is recovered as lithium carbonate. In the carbonation step, carbon dioxide is fed pH-controlled to mother liquor bleed from crystallisation batch reactor. Lithium carbonate precipitates from the concentrated lithium hydroxide solution according to following reaction: 2Li+ + 2OH- + CO2(g) = Li2CO3(aq,s) + H2O Aluminium also precipitates with the lithium as carbonate according to following reaction: 2Al3+ + 6OH- + 3CO2(g) = Al2(CO3)2(s) + 3H2O Carbonation is done at elevated temperature to minimise lithium solubility. 13.6.11 Effluent treatment Bleed from soda process filtrate and IX eluate acids are constantly pumped to the effluent storage tank. In the effluent pre-treatment area, lithium is recovered from the effluent liquor by precipitation as lithium phosphate with sodium phosphate solution feed. After precipitation, filtration and washing steps follow. Filtrate is further treated in an electrochemical water treatment process in order to precipitate soluble arsenic from the effluent stream. Solids in the effluent stream are removed by dissolved air flotation and pressure sand filtration. The treated water is discharged to a municipal wastewater treatment plant. 13.7 Process design criteria – lithium hydroxide chemical plant Key process design criteria for the lithium hydroxide chemical plant are shown in Table 13-3. Table 13-3: Key process design criteria – lithium hydroxide chemical plant Parameter Unit Value Concentrate Processing Rate (dry) tpa 156 000 Concentrate Grade % Li2O 4.5 Concentrate Moisture % H2O 11 Concentrate Fineness P80 microns 150 Plant Operating Time h 7 500 Overall Plant Availability % 85.6 LiOH * H2O Production tpa 15 000 Recovery from concentrate to LiOH x H2O product (incl. calcining) % 83.4 SRK Consulting – 592138 SSW Keliber TRS Page 177 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 13.8 Requirements for energy, water and consumables [§229.601(b)(96)(iii)(B)(14)(iii)] 13.8.1 Power In terms of the 2022 DFS Report, electric power to the lithium chemical plant will be provided by a subsidiary of a local power utility company. To enable continuous production during planned grid maintenance works, the plant will have two independent 20 kV connections to the external grid. Both power connections will be able to supply the plant at full capacity. From the main distribution switchgear, the power will be further distributed to the plant process substations by means of 20 kV underground cables. Finally, the power will be transformed to 400 V and 690 V levels in the proximity of the consumers. Kokkola plant power requirements are estimated at 12 450 kW. 13.8.2 Lithium chemical plant - site services The KIP site will provide existing infrastructure to supply the required site services. All process water qualities can be purchased from the water treatment plant operated by KIP Service Oy and process steam from the power plant of Kokkolan Energia Oy. • Process water • Demineralised water • Cooling water • Sealing water • Potable water • Fire water • Compressed and instrument air • Process steam 13.9 Plant commissioning and ramp-up [§229.601(b)(96)(iii)(B)(14)(iv)] First ore is planned to be processed through the Päiväneva Concentrator in October 2025. Twelve months has been allowed to reach design capacity as shown in Figure 13.4. First concentrate from the Päiväneva concentrator is planned to be processed through the Kokkola Lithium Hydroxide Refinery in November 2025. Twenty-four months has been allowed to reach design capacity as shown in Figure 13.4. SRK Consulting – 592138 SSW Keliber TRS Page 178 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Plant ramp-up schedules Project No. 592138 Figure 13.4: Plant ramp-up schedules Key concentration processes include comminution, ore sorting and flotation. Variation in the grindability was shown to be relatively small between the deposits and flotation parameters are reasonably well understood following bench scale testing of all deposits and pilot scale testing of Länttä, Syväjärvi and Rapasaari. XRT ore sorting was tested at pilot scale on the Syväjärvi bulk ore sample. There is a risk that ore sorting efficiency will vary across the Syväjärvi deposit and that other deposits will not perform with the same efficiency. Subject to results of further recommended investigations confirming that ore sorting, and flotation performance of other deposits is in line with Syväjärvi test results, twelve months is considered to be a reasonable ramp-up period for a concentrator of this complexity. Key refining processes include the conversion of α-spodumene to leachable β-spodumene, ahead of chemical processing of the converted concentrate to produce lithium hydroxide. While successful pilot trials on Syväjärvi and Rapasaari concentrates have significantly de-risked the flowsheet, a residual risk remains as it does with the first implementation of any novel technology. In mitigation of such risk, the Lithium Hydroxide Refinery will commence hot commissioning on third party concentrate approximately nine months before concentrate is received from the Päiväneva concentrator. In addition, a ramp-up period of twenty four months has been allowed to achieve design throughput of Keliber concentrate. Importantly, it should be noted that the Mineral Reserves for Keliber have been declared on the basis that a ready market exists for the concentrate, without the need for a refinery. 0% 20% 40% 60% 80% 100% 120% P er ce n ta ge F u ll C ap ac it y Plant Ramp-Up Concentrator Lithium Hydroxide Plant SRK Consulting – 592138 SSW Keliber TRS Page 179 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 14 INFRASTRUCTURE [§229.601(b)(96)(iii)(B)(15)] 14.1 General infrastructure The open pit mines and concentrator are situated in Central Ostrobothnia in Western Finland (Figure 7.1). Kokkola is the largest city in the area and the port has all the facilities for overseas shipments; it is ice-free all year. The nearest airport is Kokkola-Pietarsaari, which is serviced by Finnair as well as charter flights. The major infrastructure at the open pit mines (Länttä, Rapasaari, Syväjärvi, and Outovesi) comprises access roads, power transmission lines, main electrical substations, electrical distribution, security, weighbridges, offices, laboratories, workshops, crushing units, access roads to the Päiväneva concentrator and internal roads. The general layout of the mine sites is shown in Figure 14.1 (Länttä), Figure 14.2 (Rapasaari), Figure 14.3 (Syväjärvi), and Figure 14.4 (Outovesi). : SSW Keliber Lithium Project General Layout of the Länttä Mine Site (Source: Afry Finland Oy. (2021)) Project No. 592138 Figure 14.1: General Layout of the Länttä Mine Site
SRK Consulting – 592138 SSW Keliber TRS Page 180 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project General Layout of the Rapasaari Mine Site (Source: Afry Finland Oy. (2021)) Project No. 592138 Figure 14.2: General Layout of the Rapasaari Mine Site SRK Consulting – 592138 SSW Keliber TRS Page 181 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project General layout of the Syväjärvi Mine site (Source: Afry Finland Oy. (2021)) Project No. 592138 Figure 14.3: General layout of the Syväjärvi Mine site SRK Consulting – 592138 SSW Keliber TRS Page 182 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project General Layout of the Outovesi Mine Site (Source: Afry Finland Oy. (2021)) Project No. 592138 Figure 14.4: General layout of the Outovesi Mine site The Keliber Lithium Concentrator at Päiväneva is located 18 km from the municipality centre of Kaustinen in close proximity to the Rapasaari Mine Site (Figure 14.2). The major infrastructure for the Päiväneva concentrator includes: • Access road to the concentrator plant from the public road; • Raw water pumping station at Köyhäjoki, piping and water treatment plant; • One 19 km 33 kV power transmission line from the Keliber Lithium Project substation in Kaustinen to Päiväneva site; • Main electrical substations, electrical distribution, offices, laboratory. Required infrastructure for the concentrator and equipment including: • Crushing, ore storage and ore sorting; • Grinding and classification; • Magnetic separation; • Desliming; • Pre-flotation and spodumene flotation; • Concentrate dewatering and filtration; • Concentrate storage; SRK Consulting – 592138 SSW Keliber TRS Page 183 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 • Tailing ponds: two tailing ponds for process residues, flotation tailings and pre-flotation tailings and two water ponds for pit water and process water circuit; and • Small thermal plant to produce heat. Figure 14.5 shows the overall layout of the Päiväneva concentrator site: The Keliber Lithium Hydroxide Refinery is situated in the KIP at Kokkola, and an overall layout is shown in Figure 14.6. SSW Keliber Lithium Project Overall Layout of the Päiväneva Concentrator Site (Source: WSP, 2022) Project No. 581648 Figure 14.5: Overall layout of the Päiväneva Concentrator site
SRK Consulting – 592138 SSW Keliber TRS Page 184 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Overall Layout of the LiOH Plant at the Kokkola KIP Site (Source: WSP, 2022) Project No. 581648 Figure 14.6: Overall Layout of the LiOH Plant at the Kokkola KIP Site Most of the required external site services for the operation, such as security and fire brigade, are available at the KIP. The plant has all the required infrastructure for concentrate conversion and hydrometallurgical processing including an effluent treatment plant, Liquid Petroleum Gas (LPG) storage and handling facilities, main electrical substations, electrical distribution, offices, and laboratory. Certain road constructions and alterations were necessary, which include the following: • A road construction to Syväjärvi and Rapasaari mines; • A new road and intersection arrangement to access the Päiväneva Plant; and • A new road arrangement at the location of the Kokkola Plant. The infrastructure and engineering designs encompass the required infrastructure for the establishment of processing operations and the surface mine sites at a feasibility level of detail and all necessary logistics have been considered. 14.2 Tailings storage facility and ancillary infrastructure As per the Keliber Lithium Project Definitive Feasibility Study Report (February 2022), a tailings storage facility (TSF) for the Keliber Lithium Project is located within the Päiväneva plant area, to the east of the main mill area and south of the site’s waste rock dump. The TSF site is located directly north of ancient forest areas which are home to the Siberian flying squirrel and has necessitated a redesign of the latter stages of the previous TSF construction configuration to minimise impacts on the squirrels’ habitat. The high-level summary cost estimate for the TSF and associated water infrastructure is estimated to cost EUR7 million initial CAPEX (Stage 1) and EUR11.6 million sustaining CAPEX (Stages 2 to 4). A high-level review of the initial CAPEX and sustaining CAPEX appears realistic/sufficient in terms of the TSF developmental phase and the final footprint coverage of the facility. Given the natural topography (i.e. the TSF is located between two natural moraine hills and within a decommissioned peat production area), the facility is to be raised in stages, with the initial stage requiring only a SRK Consulting – 592138 SSW Keliber TRS Page 185 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 western embankment/starter wall (constructed to a height of 7m) to satisfy the Stage 1 deposition requirements. Following the construction of the Phase 1 starter wall and development of the first basin area, the eastern embankment will be constructed during Stage 2 to form the second main basin area, following which both embankments will be raised through the remaining Stages. The TSF has a final footprint of approximately 56.7 ha with a total airspace of 5.95 Mm3 and is to be constructed as a downstream-raised facility. Deposition throughout will be undertaken via hydrocycloning. Whilst the facility has not been designed to incorporate an HDPE liner, the naturally occurring peat material within the basin (average permeability of 1 x 10-9 m/s) is to be used to create a basal liner of no less than 300 mm post- compaction across the entire TSF basin. Based on geochemical analyses undertaken during 2019 from a pilot enrichment test at Lake Syväjärvi, no waste materials were determined to be potentially acid generating; however, it is noted that geochemical analyses of ore from the Rapasaari pit were not undertaken. Freeboard at the facility has been calculated using both the maximum wave height at the high water line and the depth of frost penetration, with the 1:10 year frost depth providing the final freeboard depth for the various dams at the TSF complex (based on their Class 1 and Class 2 classifications). To prevent overtopping of the tailings facility and process dams, emergency overflow pipes (ranging from 259 to 560 mm diameters dependent on the facility) are to be installed to provide for decant of process water and rainfall volumes. Stability analyses undertaken as part of the design work, including static, pseudostatic and rapid drawdown conditions, met or exceeded design criteria Factors of Safety. A HDPE and bentonite lined containment/pre-float dam directly southwest of the TSF will receive the prefloat (classified as hazardous waste), i.e. the first stage of the hydro-cycloning process, and the magnetic separation (LIMS) fraction, as well as any process water from the mine site to allow for recirculation through the plant. This dam is to be constructed in two phases, with the first phase (i.e. the western containment basin) allowing for a storage volume of 58 000m3 (approximately 9 years of storage dependent on whether there is a need to store process water). This dam's second phase (i.e. the eastern basin) allows for an additional storage volume of 59 000 m3. However, should further capacity be required within the dam, an additional third phase raise of 1m can provide any additional required future storage capacity of 29 000 m3. A return/process water dam, sized to store approximately 131 000 m3 of decanted water from the TSF, is located to the northwest of the TSF with an abutting mine water dam with a volume of approximately 107 000 m3 (receiving dewatering volumes from the open pits). Both dams will be constructed with a basal peat liner and additional clayey silt/peat/bentonite seal of 1 m high by 24 m wide constructed at the upstream toe of each embankment to minimise seepage through the wall. As per the DFS report, the TSF and ancillary dams have been designed according to the Finnish Dam Safety Guide (2018) and the Swedish Guide for Mine Dames (2010). No mention is made as to whether the TSF has been designed to GISTM requirements which came into effect in August 2020. SRK was previously advised that the detailed design of the TSF was underway in 2022; however, no final detailed design report has been issued to SRK to date. The following areas of residual risk in the designs presented in the updated DFS were identified during a 2022 audit of the facility which are not considered to represent significant issues, but should be carefully considered as the permitting progresses and detailed design phases proceed, namely these include: • The footprint area of the Flotation Tailings Pond was modified at a relatively late stage in the design process, specifically to avoid impacts on local environmental receptors (flying squirrel habitat). Whilst the design modifications are considered to be feasible, SRK notes that the facility will be raised by 2.5 m in overall height, small volumes of additional peat have to be excavated and additional tree clearance may be required. The cumulative impacts of these effects should be checked in the context of the wider EIA; • A more detailed water balance should be undertaken to ensure that maximum/minimum annual operating pond volume for each year of the mine life is estimated. It is currently unclear if a suitable pond offset can be maintained around all flanks of the Flotation Pond during both summer and winter deposition in the facility; • There has been no geochemical characterisation of the Rapasaari, Länttä, Outovesi and Emmes ore types and hence there is a residual risk that this material could exhibit acid rock drainage or metals leaching characteristics; SRK Consulting – 592138 SSW Keliber TRS Page 186 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 • No tailings settling tests have been completed to confirm drained and undrained densities for all tailings types. Whilst the value of 1.4t/m3 appears to be reasonable for the flotation tailings, this should be verified, along with the other tailings streams, to ensure that each pond has been sized appropriately; and • Limited geotechnical test work has been carried out on representative foundations samples obtained from the foundations beneath the Flotation Pond, however, this is not anticipated to have significant impact on the design, as peat depths/continuity has been extensively mapped. 14.3 Electrical infrastructure This section of the report covers only the electrical infrastructure for the open pit mines, namely Syväjärvi Mine, Rapasaari Mine, Länttä Mine and Outovesi Mine, including the Päiväneva concentrator and the Kokkola lithium chemical plant. Power supply to the Päiväneva Concentrator will be from the national power grid owned and operated by Herrfors Nät-Verkko Oy AB, the local power supply authority. Power supply will be from central Kaustinen via a 19 km long 33 kV underground cable. This cable will be routed alongside the main access road and highway 63, allowing for ease of access in future for any maintenance work that might be required. The underground cabling option has been selected due to an easier permitting process and tolerance against climate conditions. A 110/33 kV feeder bay equipped with a 16 MVA transformer will be constructed at the Kaustinen substation, from where power will be supplied to the concentrator main incoming 33 kV switchgear. The main incoming switchgear will in turn supply power to different sections around the concentrator, including Syväjärvi Mine and Rapasaari Mine, located about 3.4 km and 1.9 km respectively from the concentrator. Power will then be stepped down locally as required to supply low voltage equipment, lighting and small power. The maximum connected load of the Päiväneva Concentrator, including the two mines, is estimated at 11. 4 MW. Although the 16 MVA transformer appear to be enough to cater for the power requirements of the concentrator and the two open pit mines, SRK is of the opinion that there might be a potential risk in the bulk power supply equipment being undersized, as Rapasaari will later in its LoM include underground operations. Although the capex input tab of the economic model shows some capex allowance for Phase 2, underground development, it is not clear whether this is only for underground development or whether it includes capex for the bulk power infrastructure upgrade to cater for underground loads. Should it include the latter, SRK is of the opinion that there might be some capital saving should the bulk power supply infrastructure be initially sized to include underground operations. It is therefore recommended that the load list for Rapasaari underground be compiled to ascertain that the current bulk power supply infrastructure is enough to cater for future underground operations power requirements, so some cost savings can be achieved. The 850 kW reservation made in the load list for Syväjärvi Mine is within the right ballpark, as no underground operations are anticipated at Syväjärvi Mine in future. This reservation covers infrastructure items such as the locker room, office, area lighting, break room and a 20 kW dewatering pump. Emergency diesel generator has been allowed for at the concentrator to supply power to critical equipment during grid power failures. Länttä Mine will get its power from the existing overhead 20 kV power line, located about 200 m from the mine site. The national grid in this area is owned and operated by Verkko Korpela Oy (VKO). Power supply will be by means of a 150 m long underground cable, which will be connected between the 20 kV power line take off point and the 20/0.4 kV transformer positioned at the mine. This transformer will then supply a 400 V distribution board which will in turn supply power to all the infrastructure around the mine. Relocation of the existing power line running next to the new road will also be required, as the existing power line and the existing road are on the planned site for the open pit. It must be noted however that although it can be assumed that power requirements for Länttä open pit will also be in the region of 850 kW, no load requirements have been given in the study. Also, like Rapasaari Mine, Länttä Mine will also include underground operations later in its LoM. Although the capex input tab of the economic model shows some electrical capital cost allowance for underground development, it is not clear whether this is only for underground development or whether it includes capital for the bulk power infrastructure upgrade to cater for underground loads. Should it include the latter, SRK is of the opinion that there might be some capital saving should the bulk power supply infrastructure be initially sized to include underground operations. It is therefore recommended that the overall load list for Länttä, including underground, be compiled to ascertain that the current bulk power supply infrastructure is enough to cater for future underground operations power requirements, so some cost savings can be achieved. Outovesi Mine will be supplied with power from the existing overhead 20 kV overhead power line, owned and operated VKO. Power supply will be by means of a 3.4 km long underground cable, which will be connected SRK Consulting – 592138 SSW Keliber TRS Page 187 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 between the 20 kV power line take off point and the 20/0.4 kV transformer positioned at the mine. This transformer will then supply a 400 V distribution board which will in turn supply power to all the infrastructure around the mine. Although it can be assumed at this stage that power requirements for Outovesi will also be in the region of 850 kW, it is recommended that power requirements be given in the DFS document. Bulk power supply to Kokkola lithium chemical plant will be from the national grid, owned and operated by Kokkolan Energiaverkot Oy. Bulk power supply to the plant allows for redundancy, whereby each supply can supply full plant capacity. The maximum connected load at the Kokkola chemical plant is estimated at 12.5 MW. These supply points are readily available at the existing substations located 100 to 200 m from site. Bulk power supply will be at 20 kV, terminating at the plant main 20kV incoming switchgear. This switchgear will in turn supply power to different sections of the plant, whereby power will be stepped down locally to either 690 V or 400 V, depending on the equipment rated voltage. 690 V will be used to supply power to larger drives to optimize cable sizing, Diesel generator has been allowed at the chemical plant to supply power to critical equipment during grid power failures. Locally existing power lines and substations can and will be utilised for construction power requirements, in order to avoid excessive use of diesel generators during construction, thus reducing operating costs. However, a generator has been allowed for in the capex during construction, to cater for power supply during grid failures in order to try and avoid construction delays. Construction power requirements are estimated at 1.3 MVA for Päiväneva concentrator and 1.9 MVA for Kokkola lithium chemical plant. High efficiency and premium efficiency motors have been allowed in the designs for energy efficiency, including use of variable speed drives where possible. 14.4 Control and communications infrastructure Process control at both the Kokkola lithium chemical plant and the Päiväneva concentrator will be based on the distributed control system (DCS). The DCS is made of a number of local automatic controllers or RIO panels in various sections of the plant, whereby each process element or group of process elements is controlled by a dedicated controller. These controllers are then connected via a high speed communication network to the supervisory control and data acquisition (SCADA) system located in the control room, for monitoring and control. The SCADA system can be enhanced and expanded with additional features such as maintenance operations management, production quality management system and manufacturing resource planning, which can be purchased as separate licences and implemented at once or progressively. The DCS for both the chemical plant and the concentrator will be from a single supplier, for ease of operation and interaction. Both DCS systems will function independently from each other but can be interconnected for monitoring and data transfer over a secure network. The system will run on a redundant fibre network backbone, ensuring full availability of the system under all circumstances. Devices such as sensors and closed circuit television cameras will also be connected to the DCS through the access network interface of the RIO panels. External communications including both industrial and information technology (IT) between the chemical plant and concentrator will be through a local public network, owned and maintained by local IT service providers. The communication systems will be connected to the local network using fibre optic for high speed communication. Sufficient bandwidth will be secured by an appropriate subscription agreement. As part of information security, access to the DCS and overall business IT networks will be limited and monitored by means of individual user accounts, whereby the user accounts will be personalised and access to the system and information shall be based on the role of the employee, thus avoiding unauthorised personnel having access to confidential information. Appropriate segmentation will be provided by means of firewalls, to ensure the integrity and cybersecurity of the main network, including up to date virus protection for software protection. Mobile phone communications will be based on 4G/5G technology provided by local telecommunications operators. Should the network coverage in the Päiväneva area found to be inadequate, local antenna provided by the network operator can be provided to strengthen the signal. The communication network around Kokkola is well established and is considered enough to cover the communications requirements for the chemical plant. Generally, the communications and control systems appear to be adequately designed for the feasibility level of study.
SRK Consulting – 592138 SSW Keliber TRS Page 188 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 15 MARKET STUDIES [§229.601(b)(96)(iii)(B)(16)] The summary below is based on a 2021 Lithium Market Study conducted for Kaustinen/Kokkola DFS, by Wood Mackenzie (the Wood Mackenzie Report), as well as an independent verification lithium market study done by Fastmarkets. (2022) (the Fastmarkets Report). These market analyses cover the period up to 2031 (Wood Mackenzie) and 2033 (Fastmarkets), for which reasonably accurate market supply and demand projections were available. This period will also coincide with the bulk of the financial pay-back period for the Keliber project. Beyond 2031, market supply/demand information is scarcer and more uncertain (less reliable) but given the significant trend in electrification and the growth in use of batteries in the electric vehicle (EV) sector; coupled with the significant coinciding market deficit forecasted in 2031, it can reasonably be assumed that demand for lithium derived products will persist, supporting the commercial production of spodumene concentrate. 15.1 Context The Keliber project is a vertically integrated project that includes the mining of spodumene ore, concentrating the ore and then conversion of spodumene concentrate into battery grade lithium hydroxide. The concentrator will be sited at Paivaneva. From here the spodumene concentrate will be trucked to the Keliber owned and operated ‘Cleantech’ Chemical Plant at Kokkola Industrial Park, where a battery grade lithium hydroxide monohydrate (LiOH.H2O) will be produced along with analcime sand. A series of tests were completed to determine the production parameters of lithium hydroxide from spodumene ore, including the proprietary Metso-Outotec lithium hydroxide process at pilot scale. This included a continuous hydrometallurgical pilot plant trial that was conducted at Metso-Outotec’s Pori Research Centre from 7 to 24 January 2020 on converted Syväjärvi concentrate. There is sufficient evidence in the pilot plant results to give confidence that the design recovery figure can be achieved in practice, following a suitable ramp-up period. The Keliber project is likely to be the first implementation of this specific lithium hydroxide flowsheet. While the individual unit processes are not novel, and while the Syväjärvi (2020) and Rapasaari (2022) pilot trials have significantly de-risked the flowsheet, a residual risk remains, as it does with the first example of any novel technology. Metso Outotec will also provide a process guarantee for the plant, although such a guarantee does not ultimately guarantee a process that will work so much as it defines the extent of financial compensation that will apply should it not. SEC Regulation S-K 1300 prohibits the declaration of Mineral Reserves based on novel/non-commercialized technology, and as such it should be noted that the Mineral Reserves for Keliber have been declared based on production of a 4.5% spodumene concentrate, which was tailored to suit the lithium hydroxide refinery, and that a ready market exists for the concentrate. Typical spodumene concentrates from pegmatite orebodies grades closer to 6% spodumene, and the option exist for the Keliber project to make such a product. Given the intention to refine all the concentrate at the Keliber refinery, no contracts have been entered into for the sale of the concentrate to be produced, and it is assumed that the same terms, rates or charges could be obtained had the contract been negotiated at arm's length with an unaffiliated third party. 15.2 Uses of Spodumene Concentrate According to the Fastmarket Report, spodumene concentrate is processed into lithium carbonate and lithium hydroxide. Their main industrial use (Figure 15-1) is in the production of cathodes and electrodes for rechargeable batteries. Lithium hydroxide is preferred in the battery manufacturing industries, especially in the electric vehicles (EV) production, as it increases the performance of the battery, allowing EV to have a higher usability range before needing a recharge. It is also used as a thickener in lubricating grease as it is resistant to water and high temperatures and can sustain extreme pressures. Other uses for lithium are in mobile phones, electronic devices, laptops, and digital cameras. SRK Consulting – 592138 SSW Keliber TRS Page 189 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Global Lithium Usage by End-Market (Source: Fastmarkets) Project No. 581648 Figure 15-1: Global lithium usage by end-market – 2016, 2021 (%, LCE basis) Looking forward, traditional applications are expected to continue to grow each year at 1-3% in line with their respective sectors, but will continue to lose market share to battery demand. According to the Fastmarkets Report, traditional sectors are expected to consume 192.5 kt of LCE in 2033 – an increase of 3.0% compound average growth rate (CAGR) each year between 2021 and 2033. This compares to 3,102.4 kt of expected LCE demand in 2033 from batteries for eMobility applications and energy storage solutions –annual increases of 22.3% CAGR over the same years. 15.3 Lithium value chain Figure 15-2 below from the Wood Mackenzie Report, provides an overview of the lithium value chain in 2020. Raw materials are shown in blue and brown, representing the source of refined production and technical grade mineral products consumed directly in industrial applications. There are a number of refined lithium compounds, shown in green. Refined products may be processed further into specialty lithium products, such as butyllithium or lithium metal, shown in grey. Demand from major end-use applications is shown in orange with the relevant end-use sectors shown in yellow. Of note is that spodumene concentrate, as a raw material, predominantly gets converted into lithium carbonate and lithium hydroxide, for use in making batteries to support the automotive/transport sector. SRK Consulting – 592138 SSW Keliber TRS Page 190 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Note: The thickness of the bars relates to value in US$ SSW Keliber Lithium Project Lithium Value Chain (Source: Wood Mackenzie, Roskill, 2021) Project No. 581648 Figure 15-2: The lithium value chain Within the Li-ion battery value chain, lithium is used in manufacturing of cathode materials, electrolyte, and anode materials, with cathodes accounting for 94% of total lithium consumption in 2020. In 2020, roughly 52% of the global cathode market was divided between 15 first-tier manufacturers, including 8 manufacturers from China, while the remaining 48% market share is divided between around 100 companies globally. 15.4 Supply and demand In the case of absence of the ‘Cleantech’ Chemical Plant at Kokkola (which is planned to use all the spodumene concentrate from the Keliber project), the spodumene concentrate will have to be sold into the international conversion market. 15.4.1 Demand Demand for spodumene concentrate is driven by a demand for lithium in the first instance. Demand growth for lithium since 2009 has been driven by the rapidly increasing use of lithium in rechargeable battery applications in the form of lithium carbonate and more recently lithium hydroxide. From 2014 to 2020, demand growth for lithium has averaged 13.7% per year. The largest first use market for lithium is rechargeable batteries, which accounted for 71% of global demand in 2020 and is expected to increase further beyond that. The next largest first use market in 2020 was ceramics (7%), followed by glass-ceramics (6%). Other smaller first uses of lithium include greases, metallurgical powders, glass, polymers, air treatment and primary batteries. Demand growth for lithium in rechargeable batteries averaged 29.6%pa between 2014 and 2020. Rechargeable batteries have accounted for over 50% of lithium demand each year since 2017. Unlike most other major first-use applications, demand from rechargeable batteries continued to increase in 2020, despite disruption caused by the COVID-19 pandemic and related lockdowns. With the exception of air treatment, where lithium use has fallen throughout the past decade, all first-uses for lithium have also experienced growth over the period, albeit at slower rates than the rechargeable battery sector. The Wood Mackenzie Report forecasts global lithium demand to increase by 19.8% per year in the 2020-2031 period, reaching a total of 2.84 Mt in 2031. Growth will be predominantly driven by increasing battery production, with 2,733 GWh capacity required across all end-use applications by 2031. Regulation globally pushing for stricter CO2 emissions limits by 2030 continues to force automotive original equipment manufacturers (OEMs) to shift to hybrid and battery electric vehicles (BEV) models, a challenge which some OEMs have progressed with significantly since mid-2020, particularly in North America and Europe. The use of Li-ion batteries in EVs is embedded into the growth trend, with little risk that a significant change in technology will occur in the short to mid-term. SRK Consulting – 592138 SSW Keliber TRS Page 191 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Longer term, the development of next-generation battery technologies has the potential to both disrupt or accelerate lithium demand growth, dependent upon the prevalent technology. The demand for lithium, by products, as demonstrated in Figure 15-3, is dominated by lithium carbonate and lithium hydroxide, accounting for 70.9% of total demand in 2020. Battery-grade lithium carbonate and hydroxide demand is forecast to increase by 16.6% per year and 25.9% per year respectively in the period to 2031, reaching 863.2 kt LCE and 1,646.1 kt LCE respectively. The preference in the automotive sector to increase vehicle range will inevitably shift battery production toward nickel-rich chemistries, which in turn will see demand for lithium hydroxide increase faster than demand for lithium carbonate. Note: Other includes technical grade hydroxide, butyllithium and bromid SSW Keliber Lithium Project Global Demand for Lithium by Product (Source: Wood Mackenzie, Roskill, 2021) Project No. 581648 Figure 15-3: Global demand for lithium by product, 2014 -2031 (Kt LCE) In 2020, China was the largest consumer of lithium (Figure 15-4), accounting for 63% of total demand or 243.1 kt LCE. Chinese demand has increased by 15.2% per year since 2014, largely through rapid expansion of the domestic Li-ion battery sector with supplementary growth in industrial end-use markets. European demand has also risen significantly in the period since 2014, with the majority of growth occurring in the period since 2018 with greater Li-ion battery manufacturing taking place in the region. European demand growth is strongly supported by both government legislation and private investments with several battery production facilities in Sweden, Germany, France, and the UK, amongst others, planned for commissioning over the period to 2031.
SRK Consulting – 592138 SSW Keliber TRS Page 192 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 SSW Keliber Lithium Project Global Demand for Lithium by Region (Source: Wood Mackenzie, Roskill, 2021) Project No. 581648 Figure 15-4: Global demand for lithium by region, 2014 -2031 (Kt LCE) Until 2017, there was little Li-ion battery manufacturing capacity in Europe, however, in the past few years, the region has made impressive progress. In 2020, Europe had Li-ion battery manufacturing capacity of 39.9 GWh, accounting for 5.7% of the global manufacturing capacity. The Wood Mackenzie Report forecasts the European Li-ion battery manufacturing capacity could reach 1,040 GWh by 2030. The global distribution of mineral conversion facilities (Refineries) where Spodumene Concentrate from the Keliber project can alternatively be converted to lithium carbonate and lithium hydroxide is highly concentrated in China. On a country basis, China controlled over two thirds of global refined production in 2020, with Chile and Argentina in second and third at 19% and 6% respectively. Production from Chile and Argentina is solely from brine operations and is not suitable to treat spodumene concentrates. This compares to China’s diversified production from both mineral and brine sources, where it currently controls over 99% of mineral conversion production globally. In 2021, global production of refined compounds was forecasted to total 636.3 kt LCE. Based on announced capacity expansions, output is forecast to increase at a CAGR of 7.9% to 2031. Under this scenario, production is forecast to surpass 1.0 Mt LCE in 2026 before reaching 1.2 Mt LCE by 2031. China is expected to remain the largest centre for refined lithium production – the country was forecasted to account for 71.4% of global production in 2021, with output from both mineral conversions, reprocessing and lithium brine sources. Mineral conversion companies have increasingly sought to integrate upstream, in efforts to remove supply-chain risk and additional margin between the mineral concentrate and mineral conversion stages. Despite this, the development of new production capacity reliant upon the free-market or off-take agreements with mineral concentrate producers has outpaced integrated production in terms of year-on-year growth between 2014-2020. Between 2015-2020, production from integrated refined capacity has increased at a CAGR of 19.9%. Production from independent capacity has increased at a faster rate of 43.6% per year over the same period, although the growth has occurred from a very low base. This would suggest that there will be an increasing number of refineries to which the Keliber spodumene concentrate could be sold to. In 2020, production of lithium compounds by mineral conversion totalled 230.4kt LCE, increasing 4.8% from 219.8 kt LCE the previous year. Together, the two largest mineral converters Ganfeng Lithium and Tianqi Lithium, formed 34.8% of global production in 2020 with combined output of 80.1 kt LCE across four facilities in China. If spodumene mineral conversion is only considered, Ganfeng and Tianqi’s market share jumps to over 45% of global production in 2020. SRK Consulting – 592138 SSW Keliber TRS Page 193 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 15.4.2 Supply 15.4.2.1 Mine supply Between 2014 and 2019, growth in mine production of chemical-grade mineral concentrates averaged 43.2% per year. A peak level was reached in 2019 at 264.0 kt, before production fell to 232.9 kt in 2020 due to a slump in demand and build-up of inventories. Based on announced capacity expansions and new project schedules (Figure 15-5), production of mined chemical grade mineral concentrates is forecast to increase at a CAGR of 11.2% from 2020 to 2031, with total production reaching 745.9 kt LCE. Note: DSO is Direct Shipped Ore SSW Keliber Lithium Project World Mine Production of Chemical-Grade Mineral Concentrate by Country (Source: Wood Mackenzie, Roskill, 2021) Project No. 581648 Figure 15-5: World mine production of chemical-grade mineral concentrate by country, 2014 -2031 (Kt LCE) Mined chemical-grade mineral concentrate production is dominated by Australian operations, which had a combined capacity of 221.8 kt LCE in 2020, including projects on care & maintenance. This volume accounts for 85% of global mined chemical-grade production. Production growth up to 2019 was underpinned by expansions and commissioning of new capacity, particularly in 2017, when Australian chemical-grade mineral concentrate production increased by 103% year-on-year in response to high lithium compound and spodumene concentrate prices. Most of the world’s large lithium mines are in Australia and their output of spodumene concentrates or DSO (Direct Shipped Ore) is destined almost entirely for mineral conversion facilities in China. As shown in Figure 15-5, from 2020 to 2031, growth in mine production of chemical-grade mineral concentrate will largely be driven by Australia, with a forecast CAGR of 12.4% over the period to 632.0 kt LCE. Production of mined chemical-grade concentrate in China fell sharply in 2018 to 13.7 kt LCE from 20.1 kt LCE in 2017, as a result of large volumes of material from Australia being made available to Chinese consumers. This increase in supply led to prices falling and the Chinese operations becoming less competitive, resulting in lower production. The suspension of production at some Australian operations caused a resurgence in Chinese domestic production during 2019 and 2020, with mine production of chemical-grade mineral concentrate in 2020 totalling 50.8 kt LCE. Chinese production of mined chemical-grade mineral concentrate accounted for 21.8% of world production in 2020. This is forecast to grow at a CAGR of 6.5% to 2031, reaching production levels of 101.0 kt LCE. Despite this growth, China’s production is forecast to decline to 13.5% of global production by 2031. SRK Consulting – 592138 SSW Keliber TRS Page 194 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 15.4.2.2 Refined lithium production • Lithium Carbonate The production of refined lithium compounds is derived from output from mineral conversion, brine production, low-grade compound upgrading/reprocessing and recycling refineries. In 2020, global refined production of lithium carbonate totalled 333.5 kt LCE. Global refined production increased at a CAGR of 19.8% in the 2014-2020 period, driven by expansions to brine operations in South America and new and expanding mineral processing facilities in China. Brine-based production has been the dominant source of carbonate output, accounting for 53% of total production in 2020. Production in South America continues to dominate carbonate output from lithium brine operations. The strong growth in demand for lithium carbonate for use in the Li-ion battery industry has led to producers targeting production of battery-grade lithium carbonate rather than production of technical-grade lithium carbonate which is simpler and cheaper to produce. Battery-grade output accounted for 53% of production in 2020, compared to 36% in 2014. Technical-grade lithium carbonate production increased from 60.2 kt LCE in 2014 to 160.2 kt LCE in 2020, with the commissioning of new lithium brine and mineral processing facilities where production of technical-grade lithium carbonate is common ‘first product’, while the plant goes through commissioning stages towards steady- state. A number of facilities were reported to sell off-spec battery grade lithium carbonate as technical grade material, which boosted technical-grade supply. Global refined lithium carbonate production is forecast to increase at a CAGR of 7.0% in the 2020 to 2031 period to reach 784.2 kt LCE. Refined lithium carbonate production is expected to be dominated by production from brine in the coming years. • Lithium hydroxide In 2020, global lithium hydroxide production totalled 140.3 kt LCE. Global production increased at a CAGR of 30.7% in the 2014 to 2020 period. Unlike carbonate, hydroxide is expressed on a final product basis as it is truest reflection of total hydroxide production. This comes as a result of lithium hydroxide being an end-user product by nature and deriving from two main sources: mineral conversion, and carbonate conversion. Lithium hydroxide production has seen rapid and sustained growth since 2014, although production continues to lag significantly behind lithium carbonate. From a product point of view, producers have responded to end-users’ shifting demand preferences to battery-grade products for use in lithium-ion batteries. Battery-grade hydroxide production totalled 125.3 kt LCE in 2020, representing 89% of lithium hydroxide production compared to 24% in 2014. Up to 2018, carbonate conversion was the dominant source of refined lithium hydroxide output. During 2019, production from mineral concentrates became the dominant source, accounting for 53% of production, which increased to 61% in 2020. The increase in mineral conversion production of lithium hydroxide has been led by Chinese based refineries. Chinese output increased from 43.9 kt LCE in 2018 to 112.6 kt LCE in 2020. In the 2020 to 2031 period, lithium hydroxide production is forecast to increase at a CAGR of 14.6% to reach 627 kt LCE. The commissioning of large-scale lithium hydroxide facilities in Australia and China in the coming years is expected to increase the dominance of mineral processing over carbonate conversion for refined lithium hydroxide production. Mineral processing is forecast to account for 82% of refined lithium hydroxide production in 2031, up from 71% in 2021. On a country basis, China controlled over two thirds of global refined production in 2020, with Chile and Argentina in second and third at 19% and 6% respectively. Production from Chile and Argentina is solely from brine operations at Salar de Atacama, Hombre Muerto and Olaroz. This compares to China’s diversified production from both mineral and brine sources, where it currently controls over 99% of mineral conversion production globally. • Spodumene concentrate There is not a secondary market for spodumene concentrate, and as such the reported price is determined by contracts between producers and offtakes (who are in this case either integrated producers or third-party refiners). Demand outlook for spodumene concentrate is directly linked to the outlook for lithium, with some bias towards lithium hydroxide demand as it involves fewer processing stages (i.e., lower refining cost) than from using brines. SRK Consulting – 592138 SSW Keliber TRS Page 195 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 A 4.5% spodumene concentrate, as opposed to a 6% spodumene concentrate is still expected to be in demand, albeit at a reduced price. 15.5 Market balance Figure 15-6 below illustrates the forecast lithium compound (including hydroxide and carbonate) market balance for the 2022-2031 period. The Wood Mackenzie Report forecasts surpluses of total lithium chemical in the next few years. In 2024, a surplus of 446 kt LCE is forecast as significant projects are entering the market. As demand is forecast to rise in the coming years, a supply response is likely and would be provided for by increasing significant latent and dormant industry capacity utilisation. The supply surplus, however, is not even across products and grades with significant brine projects entering the market supplying lithium carbonate, while demand will be a mix of battery-grade lithium carbonate and battery-grade lithium hydroxide. As a result, prices are expected to behave differently to what would be expected by the overall lithium chemical balance. SSW Keliber Lithium Project Global Lithium Compound Market Balance (Source: Wood Mackenzie, Roskill, 2021) Project No. 581648 Figure 15-6: Global lithium compound market balance, 2022 -2031 (kt LCE) Between 2023 and 2026, the market is forecast to be relatively balanced, with residual stocks and initial volume from new projects alleviating periods of tightness according to the Wood Mackenzie Report. This period of balancing is the core theme of the medium-term outlook set out in the Wood Mackenzie Report. Such a period is largely predicated on re-commissioning capacity on care and maintenance and the timely construction of additional projects. Should either fail to take place, sustained demand growth would orchestrate the beginning of structural supply deficits by 2027. Regardless, the Wood Mackenzie Report considers this period the transitional phase from relative tightness to supply deficit, though it is unclear at what stage this may eventuate. In the long-term, however, the refined market is forecast to enter a period of supply deficit, particularly beyond 2027. Assuming all new supply in the base case of the Wood Mackenzie Report, care and maintenance and additional new projects are brought online, there is potential for the market to remain supply sufficient until 2027. Although the likeliness of this taking place according to recent track records of project financing, development and commissioning would suggest otherwise. Beyond 2027, the Wood Mackenzie Report forecasts significant structural market deficits arising. It is salient not to view this period as purely from a market deficit quantification point of view. Conversely, the Wood Mackenzie Report considers these events to reflect the ‘investment requirement’ of supply rather than what is suggested to transpire. This is mostly due to the higher level of uncertainty and variables to account for.
SRK Consulting – 592138 SSW Keliber TRS Page 196 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 15.6 Prices Assessing the market price of spodumene concentrate remains challenging (Figure 15-7) as no official trading index exists. International trade is carried out on a generic product code and the number of suppliers remains very limited. Historically, only Talison Lithium Pty Ltd (Talison) has been producing spodumene concentrate but with production starting at Mt Cattlin and Mt Marion in 2017 the dynamics of the market changed to include ‘arm’s length’ or ‘related’ prices rather than prices for fully integrated sales. In recent years, a ‘market price’ approach has been taken by all producers to ensure compliance with taxation requirements in Australia, as well as to ensure the value of a dynamic lithium compound market is captured at the resource side of the market. In 2014, the price of chemical-grade spodumene concentrate averaged US$386/t CIF China, increasing to a peak of US$1 031/t in 2018 before dropping to US$440/t in 2020. Note Forecast price are real 2021 USD. Historical prices are in nominal terms SSW Keliber Lithium Project Average Annual Contract Price Forecast for Chemical Grade Spodumene (Source: Wood Mackenzie, Roskill, 2021) Project No. 581648 Figure 15-7: Average annual contract price forecast for chemical grade spodumene (US$/t) Sustained higher lithium carbonate and lithium hydroxide prices, as well as increasing demand for chemical grade spodumene concentrates are expected to support contract prices increasing substantially to average US$670/t CIF Asia in Q4 2021, before rising further to average US$926/t in 2022. Spot prices for chemical grade spodumene concentrate are expected to remain at current high levels as demand for limited non-contracted volume increases in line with increasing demand for lithium chemicals. Under the base case, the Wood Mackenzie report forecasts contract prices of chemical-grade spodumene concentrate to rise to US$1 051/t in 2023, before declining to US$796/t in 2024, followed by a steady rise to US$1 142/t by 2031. For the purpose of the financial analysis of the Keliber project, a price adjustment to 75% of a 6% concentrate has been assumed, as a direct method to ensure both revenue and costs remain consistent. SRK Consulting – 592138 SSW Keliber TRS Page 197 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 16 ENVIRONMENTAL AND SOCIAL STUDIES [§229.601(b)(96)(iii)(B)(17)] As discussed in section 2.4.1, Keliber has completed all relevant EIA procedures to proceed with the Keliber Lithium Project. Keliber holds a valid environmental permit for the Syväjärvi mining operations and a water permit for dewatering Syväjärvi Lake and Heinäjärvi Lake. A valid permit states that the permit decision issued by the Regional State Administrative Agency (AVI) was appealed and appeals were processed in the Vaasa Administrative Court, which ruled against appeals and kept AVI’s permit decision in force on 16 June 2021. There were no appeals made to the Supreme Administrative Court against the Vaasa Administrative Court’s decision. The Syväjärvi environmental permit became final in July 2021. Keliber holds an environmental permit for Länttä, issued in 2006. The permit is valid for mining and operations as described in the permit application. If operations or excavation volumes increase, Keliber may need to apply for a new environmental permit. The Länttä Mine is not scheduled to commence before 2037 so detailed engineering has not yet been started. The Rapasaari Mine environmental permit application was submitted to AVI on 30 June 2021. The Päiväneva Concentrator environmental permit was submitted to AVI on 30 June 2021. Concentrator operations require a water permit for raw water intake from the Köyhäjoki River and that permit application was also submitted to AVI on 30 June 2021. Keliber received environmental permits for the Rapasaari Mine and Päiväneva Concentrator in December 2022 (Environmental permit 208/2022 number: LSSAVI/10481/2021, LSSAVI/10484/2021). For the Keliber Lithium Hydroxide Refinery located in Kokkola, an environmental permit application was submitted to AVI on 4 December 2020. The environmental permit decision is awaited. Keliber received environmental permits for the Rapasaari Mine and Päiväneva Concentrator in December 2022 (Environmental permit 208/2022 number: LSSAVI/10481/2021, LSSAVI/10484/2021). 16.1 Environmental Impact Studies Results 16.1.1 Groundwater Studies According to the EIA 2020 report Syväjärvi, Rapasaari, Outovesi and Päiväneva groundwater samples have been collected from observation wells during the years 2018 – 2020. In the EIA 2020 reports the groundwater quality sample results have been compared to the Decree of the Ministry of Social Affairs and Health (1352/2015, amendment 683/2017) chemical quality standards and objectives for drinking (potable) water. Results indicated that groundwater quality in most samples meet drinking water quality standards with the exception of the elements iron and manganese. Elevated iron and manganese are the result of higher chemical oxygen demand, and low oxygen levels. This is a result of the impact of humus-contained waters from the surrounding peat lands. Natural concentrations of ammonium also exceed recommendations for household water quality. 16.1.2 Biodiversity Starting from 2014 several studies concerning vegetation, habitats, flora and fauna have been carried out. Based on the EIA 2020 report and information received from Keliber the list of studies which have been conducted over the years at the mine sites and surrounding areas is provided in Table 16-1. SRK Consulting – 592138 SSW Keliber TRS Page 198 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Table 16-1: Field studies carried out at Syväjärvi, Rapasaari and Outovesi mine sites and Vionneva natura 2000 area. Site Study period Executor SYVÄJÄRVI Vegetation 2014 – 2015, 2020 Ahma Ympäristö 2015, Envineer Oy 2020 Habitats 2014 – 2015, 2020 Ahma Ympäristö 2015, Envineer Oy 2020 Nesting birds 2014, 2020 Ramboll Finland 2014e, Envineer Oy 2020 Moor Frog 2014 – 2021 Ramboll Finland 2014cd, Tutkimusosuuskunta Tapaus 2015-2021 Bats 2014, 2020 Ramboll Finland 2014a, Envineer Oy 2020 Siberian Flying Squirrel 2014, 2020, 2021 Ramboll Finland 2014, Envineer Oy 2020, Saarikivi, J. 2021 Predaceous diving beetles 2018, 2019 Tutkimusosuuskunta Tapaus, 2018, 2019, 2020 Dragon flies 2018 – 2020 Tutkimusosuuskunta Tapaus, 2018-2020 Fish 2014 Nab Labs 2014 Benthic invertebrate fauna 2014, 2020 Ahma 2015 Diatoms 2014 Eloranta 2014 RAPASAARI JA OUTOVESI Vegetation 2014 – 2015 Ahma Ympäristö 2015 Habitats 2014 – 2015 Ahma Ympäristö 2015 Nesting birds 2014 Ramboll Finland 2014e Moor Frog 2014-2021 Ramboll Finland 2014cd, Tutkimusosuuskunta Tapaus 2015-2021 Bats 2014, 2020 Ramboll Finland 2014a, Envineer Oy Siberian Flying Squirrel 2014, 2020, 2021 Ramboll Finland 2014, Envineer Oy, Saarikivi, J. 2021 Predaceous diving beetles 2018, 2019, 2020, 2021 Tutkimusosuuskunta Tapaus Dragon flies 2018 – 2019 Tutkimusosuuskunta Tapaus, 2018, 2019 Fish 2014, 2020 Nab Labs 2014, AFRY Finland Oy 2020b Benthic invertebrate fauna 2014, 2020 Ahma 2015, Vahanen Environment Oy 2020 Diatoms 2014, 2020 Eloranta 2014, Vahanen Environment Oy 2020 Otter 2020 Envineer Oy 2020 VIONNEVA NATURA AREA Nesting Birds 2014 – 2018, 2020 Tikkanen and Tuohimaa 2014, Ramboll 2016, 2018, Envineer Oy 2020 In the following text the directive habitat species, as identified during above studies, and Keliber’s actions to protect habitats are presented. • Moor frog o Keliber has built four moor frog ponds outside of the Syväjärvi mine site. The purpose of the ponds is to secure favourable conservation status and to provide moor frogs a place to breed and rest, thus improving the habitat of the moor frogs in the area. • Siberian Flying squirrel o The Siberian flying squirrel (Pteromys volans) is a species classified as vulnerable (VU), and strictly protected by the Habitats Directive. Elsewhere in the EU, the Siberian flying squirrel only occurs in Estonia. o Keliber has designed its operations so that the ancient forest area where the flying squirrel was detected will be preserved. In response to interactions with ecologists, Keliber has, in its 2021 design engineering work, relocated the south dam wall of the tailings storage facility further away from the ancient forest area. • Bats o The bat is a species listed in the Habitats Directive IV(a) of the European Union’s Convention on Biological Diversity. SRK Consulting – 592138 SSW Keliber TRS Page 199 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 o Keliber, are preserving the bat resting place at the Syväjärvi mine site by changing the infrastructure design and moving infrastructure close by. o Additional resting places will be added as well. • Otter o In the field survey carried out during the EIA assessment in 2020, traces of otters were observed on the snow on the shores of streams Näätinkioja (also named as Kärmeoja) which is south of the Päiväneva concentrator area. o The 2020 field survey of otters was the first of its kind conducted in the area. o Keliber has decided to carry out more field surveys to have more precise information on where otters live and breed. With more precise information Keliber may help to protect and preserve otter population in the area. • Golden eagle o The golden eagle (Aquila chrysaetos) is not listed in the Habitat Directive Annex IV(a) but is classified as vulnerable in Finland. o To protect and to improve golden eagle territory at Vionneva, Keliber has taken following actions: ▪ artificial nests have been built further away from mine sites; ▪ artificial feeding during wintertime has been started to improve the success of nesting; and ▪ satellite tracking of the male eagle is ongoing. 16.1.3 Air Quality AFRY Finland Oy has modelled potential dust impacts of Syväjärvi and Rapasaari mine operations and Päiväneva concentrator operations with the results reported in: Keliber Technology Oy, Rapasaaren ja Syväjärven kaivosten pölypäästöjen leviämismallinnus, AFRY Finland Oy, 4.11.2021 (Finnish). AFRY made the dust dispersion calculations by using the Breeze Aermod model tool developed by the US Environmental Protection Agency. According to the AFRY dust model report 4.11.2021, modelled results show that respirable particulate matter (PM10) limits are not exceeded at the nearest holiday homes in any modelled situations due to the mining activities at Syväjärvi and Rapasaari and the concentrator operations in Päiväneva. 16.1.4 Noise AFRY Finland Oy has carried out a noise model for Keliber with the results reported in Finnish in the report: Keliber Technology Oy, AFRY Finland Oy 2.11.2021. The modelling was done by using SoundPlan v8.2, noise calculation software. The report is part of the environmental permit application for Rapasaari mine and Päiväneva concentrator. Noise model results for the Rapasaari mine and Päiväneva concentrator plant have been compared to noise limit values stated in the Syväjärvi environmental permit decision. Based on the noise modelling results reported by AFRY, the results for the average noise level LAeq are below the average noise level of the limit values for Syväjärvi. According to the modelling, the Vionneva Natura2000 area could be affected by noise levels greater than 50 dB, especially in the early years of the Rapasaari mine operations when the waste rock area is still shallow. As the Rapasaari mine progresses, noise impacts on the Vionneva Natura area are reduced. 16.2 Water Management Keliber has developed detailed The Site Water Management Plan which combines the project site water management data into one document, and includes subsequent modelling and assessment tasks: • Rapasaari mine site hydrogeological modelling; • Rapasaari – Päiväneva area source term models (water qualities and quantities for extractive waste facilities, pit, and underground mine), operational and post closure phases; • Rapasaari – Päiväneva complex site-wide water balance modelling; • Syväjärvi open pit hydrogeological modelling;
SRK Consulting – 592138 SSW Keliber TRS Page 200 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 • Site hydrogeological assessment of the Länttä, Outovesi, and Emmes mine sites; • Water quality summaries for Syväjärvi, Länttä, Outovesi, and Emmes mine sites (based on existing data); and • Rapasaari-Päiväneva Complex, Conceptualization of Site Water Management Related Components. 16.2.1 Surface waters and groundwater All planned mine sites are in the River Perhonjoki catchment area. Syväjärvi mine is in the catchment of the River Ullavanjoki while Rapasaari mine and concentrator are in the catchment of the River Köyhäjoki. River Ullavanjoki starts from Lake Ullavanjärvi which is upstream of Syväjärvi mine and therefore Syväjärvi mine has no impact on the Lake Ullavanjärvi. Länttä mine is in the catchment of Lake Ullavanjärvi. Both Outovesi and Emmes mines are also located in the catchment area of the River Ullavanjoki. The Emmes deposit is mainly located underneath Lake Emmes-Storträsket, which is one of the basins in the lake chain of the River Perhonjoki. Syväjärvi has a valid environmental and water permit (LSSAVI/3331/2018, 20th February 2019 and administrative court decision 16th June 2021, 21/0097/3). The permit consists of permit conditions including water management principles, permit conditions for dewatering and sediment removal from the lakes Syväjärvi and Heinäjärvi, and acceptable emission levels. The Syväjärvi mine site water management system has been designed to meet the requirements of permit conditions. All water management structures, and water quality monitoring are determined in the environmental permit. When executed accordingly the risks to environment, to water bodies or to flora or fauna are mitigated. After the Syväjärvi mining operation has ended, the embankments at Lake Syväjärvi and Lake Heinäjärvi will be demolished and drainage pumping of open pit water stopped, allowing surface and groundwater to enter the pit. By slowing water flow through the Syväjärvi open pit, some modifications to surface watershed area can be achieved e.g., limit flow within ditches. In this way water quality can be controlled. In the early phase of post- closure, when the open pit is filling with water, any excess water is discharged in a controlled manner through a wetland to remove any solids. The open pit is estimated to take around 5-10 years to fill. Estimation of groundwater inflow to the open pit when it is as its largest is 710 m3/d. The dewatering amount including direct precipitation into the pit is approximately 840 m3/d. In this dewatering amount, evaporation is assumed to be 50 % of the total precipitation. The radius of the drawdown cone is a few hundred metres from the pit. As explained in the AFRY report of Syväjärvi Hydromodel, Pit dewater flow is directed to sedimentation ponds and on to a wetland before flowing to Ruohojärvenoja Ditch. Separate environmental permit applications for the Rapasaari mine and Päiväneva concentrator have been submitted to the Regional State Administrative Agency (AVI) on June 30th, 2021, approved 28 December 2022 but under appeal currently. Water management and water quality before, during, and after the operational phase of the Rapasaari – Päiväneva complex is described in detail in the Water Management Plan by AFRY Finland Oy. An ecological status assessment and assessment of impacts from mining operations on surface water quality and ecological status of surface waters from the Rapasaari – Päiväneva complex has been conducted by Vahanen Environment Oy, report in Finnish: Louhostoiminnan ja rikastamon vaikutus pintavesien ekologiseen tilaan, 8.11.2021. Raw water needed for concentrator processes is pumped from the River Köyhäjoki at Jokineva and downstream of the water intake is also the discharge point for waste water. The surface water impact of the Rapasaari – Päiväneva complex is caused by storm run-off from the Rapasaari mine site, leachate from the waste rock, tailings, moraine, and peat deposition areas, and process water from the concentrator. The waters will be treated centrally in Päiväneva water treatment plant, where there are unit processes for the treatment of raw water, removal of solids from process water circulation and removal of solids and arsenic from wastewater as well as biological nitrogen removal from mine water. According to Rapasaari Numerical Groundwater Flow Modelling - Rapasaari Open Pit and Underground Mine by AFRY, groundwater inflow into the Rapasaari open pit when the pit is at its largest (southern open pit extension included) will be 2,680 m3/d. The dewatering amount including precipitation into the pit at this stage will be approximately 3,100 m3/d. Mine water is pumped to the mine water pond then to the nitrogen removal process and from there to the recycle water pond from which it can be released as effluent to Köyhäjoki Stream. According to the AFRY waste management plan for Rapasaari mine 5.11.2021 some seepage water from waste rock areas and the tailings storage facility will occur. From waste rock areas seepage flows to the open pit and from the TSF seepage enters groundwater where it dilutes. The sealed bottom structure of the pre-float tailings SRK Consulting – 592138 SSW Keliber TRS Page 201 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 facility and of the pyrite-containing waste rock storage area will minimize seepage water effectively. Keliber will incorporate these features in the detailed design. 16.2.2 Effects on surface waters During the construction phase, digging and relocation of soil could impact on water quality of the Näätinkioja Stream by temporarily increasing turbidity and concentration of suspended solids in the stream. The impact will be minimized by preparing first the sedimentation ponds to collect runoff water from the area. While this is done, it will hinder storm waters to reach Näätinkioja decreasing the surface runoff to Näätinkioja to 4 %, which is insignificant change for flora and fauna of the Näätinkioja. During the operation phase, the effluent from the Rapasaari – Päiväneva complex is treated, collected to the recycle water pond and then discharged into the Köyhäjoki at Jokineva via pipeline. The decision on the location of discharge was made because the Köyhäjoki is a much larger river than Näätinkioja Stream and during the EIA process a trout population was found to live and spawn in the Näätinkioja. Since nitrogen load from explosives is a major concern, water treatment includes nitrogen removal. To avoid eutrophication, it is important to control nitrogen concentration since the concentration of phosphorus in the tailing storage facility waters is also significant. Nitrogen is removed until a concentration of 7.5 mg/L is achieved. Arsenic will be removed before water is circulated to the Recycle Water Pond from the Pre-float Tailings Pond. Suspended solids are removed from water to a concentration of 15 mg/L before discharge to river Köyhäjoki can occur. The volume of effluent discharged into the Köyhäjoki will peak in the years 8 to 10 of operation at around 170- 200 m3/h. The concentrations of contaminants in the water bodies during that period were modelled and compared to Finland’s national reference values. In the absence of national reference values, international values such as from European Chemicals Agency (ECHA), U.S. Environmental Protection Agency (EPA), and Canadian Council of Ministers of the Environment (CCME) were used. The studied contaminants consisted of more than 40 elements and minerals. The modelling was conducted for three spots: 1) at the discharge in the Jokineva, 2) 10 km downstream from Jokineva, and 3) just before the Köyhäjoki flows to the lake chain 20 km from Jokineva. Cobalt, zinc, and vanadium exceeded the national reference values, but for cobalt and zinc even the baseline concentrations are above the reference value. It is notable that the national reference values are for soluble concentration while the modelling was conducted for total concentrations and is therefore conservative. Nutrient loading (P and N) from the Rapasaari – Päiväneva complex to the Köyhäjoki was compared to total annual nutrient loading based on VEMALA modelling, which is an operational, national scale nutrient loading model for Finnish watersheds operated and developed by the Finnish Environment Institute. Based on calculations by AFRY Finland Oy, the Rapasaari – Päiväneva complex is expected to release less than 10% nitrogen and less than 5% phosphorus to the Köyhäjoki during the operational years 8-10. According to VEMALA, total current annual nitrogen loading to Köyhäjoki Agriculture is the main source of both nitrogen (40 % of the annual N load) and phosphorus (54 % of the annual P Load) in the Köyhäjoki catchment area. After mine closing, discharge to the Köyhäjoki in Jokineva will cease and the Rapasaari pit will be allowed to fill naturally with water. During and after the filling, leaching of nutrients and contaminants to the Näätinkioja Stream could occur. The modelling for water quality was conducted for three post closure phases. Phosphorus concentration increased 20-25 µg/L and nitrogen 8-68 µg/L, depending on the phase. Such a low increase in nutrient loading to Näätinkioja Stream does not adversely affect water quality, flora, and fauna of the stream. In each post-closure phase, cobalt slightly exceeds the reference value, which is 0.5 µg/L according to publication of Ministry of Environment, but the baseline value is 0.45 µg/l. Increase in concentration for other elements is negligible. An ecological status assessment and assessment of impacts from mining operations on the ecological status of surface waters from the Rapasaari – Päiväneva complex was conducted, the full report of which is available in Finnish and is included in the environmental permit application for Rapasaari mine and Päiväneva concentrator. According to the assessment, water discharge from the Rapasaari – Päiväneva complex does not have a negative impact on the ecological status of surface waters bodies on the discharge area or further downstream. The implementation of the Päiväneva production area will not hinder the achievement of water management, marine SRK Consulting – 592138 SSW Keliber TRS Page 202 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 conservation objectives or the implementation of water protection action plans. Furthermore, the recreational use of the waters downstream of the Päiväneva production area, recreational fishing and crayfishing, are not expected to be adversely affected. The water management structures have not yet been designed for the Länttä mine. In general, the water management structures will consist of water collection and discharge structures. According to the valid environmental permit of Länttä, mine dewatering systems will pump water to sedimentation ponds. The Outovesi mine is located in the River Ullavanjoki catchment area. Small ponds, Lake Outovesi, Lake Kotalampi and Lake Länkkyjärvi are all upstream from Outovesi mine and therefore not affected by the mine waters. The operations in Outovesi will be only short-term, and the current designs lack water management plans. The principle is, however, that Outovesi pit dewatering water and runoff water streams from deposition areas, as well as other site water streams, will be managed at their area of formation and, if necessary, treated with suitable treatment methods. 16.2.3 Potentially Sulphate Soils The GTK conducted a sulphate soil survey in 2014 at the Rapasaari, Syväjärvi, Outovesi and Länttä mine sites. The GTK study assessed the potential risk of soil acidification due to land use or drainage. Acid sulphate soils are known to pose a risk of acidification to soil and water bodies if non-oxidized sulphide-rich soil layers below the water table are exposed to oxidation. Typically, these layers or soil masses are oxidized during drainage or excavation of the soil. AFRY Finland Oy conducted a sulphate soil survey at the Päiväneva concentrator area in 2020 [21] . In total, 21 soil samples from four locations were taken and analysed for total sulphur content and acid-producing potential with a NAG-test. According to the AFRY report, the test results show the soil is not naturally acid producing. 16.2.4 Acid producing waste rock At Syväjärvi, pyrite-containing mica-schist makes up 2 % of the waste rock and is potentially acid producing. At Rapasaari, pyrite-containing waste rock makes up 1 % of the waste rock and is potentially acid producing. Outovesi waste rock has some potential for acid producing. Länttä waste rocks should not be acid producing. According to the EIA 2020 report, the acid producing and neutralizing potential for waste rock has been determined by ABA-tests. Some of the Syväjärvi mica schist and intermediate metatuffic/meta vulcanite was classified as potentially acid producing and pyrite-containing mica schist as acid producing. At Rapasaari, only mica schist was classified as acid producing. Outovesi samples were all classified as acid producing. Keliber will install the following structures to waste rock areas of potential acid production. To prevent acid leachate entering soil or groundwater from acid producing waste rock areas, a mineral sealing layer will be built on top of the subsoil moraine with layer thickness 1 m, a bentonite mat will be laid on top of the moraine layer and an HDPE membrane, protected by a geotextile (sizing according to the material supplier's instructions) or with a layer of sand. Pre-filling will be done with waste rock with the pre-fill layer will acting as both protection of the sealing structure and as an access and working platform for machinery. Surrounding the storage area will be a sealing base (mineral aggregate, mats, bentonite mats and HDPE membrane), from which leachate will be collected and directed to the pre-float tailings equalization pond. From the equalization pond, the leachate will be pumped to the pre-float pond at the concentrator. This applies to Syväjärvi and Rapasaari mine sites where acid producing waste rock is likely to be encountered. Detailed engineering for the Outovesi mine site has not been started yet but acid producing waste rock will be noted in the design. Handling of acid producing waste rock and waters generated in these areas is described in detail in the waste management plan by AFRY Finland Oy. 16.2.5 Waste Disposal Government Decree 190/2013 for extractive waste applies to the preparation and implementation of an extractive waste management plan; the establishment, management, decommissioning and after-care of an extractive waste disposal site; the recovery of extractive waste in an opencast mine and the monitoring, supervision, and SRK Consulting – 592138 SSW Keliber TRS Page 203 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 control of the management of extractive waste. An extractive waste management plan is mandatory in order to start mining operations and the plan is also a mandatory part of the environmental permit application. According to Section 114 § of the Environmental Protection Act (527/2014), the operator must evaluate and, if necessary, revise the plan for the management of extractive waste at least every five years and inform the supervisory authority thereof. Under Article 114 § point 4 of the Mining Waste Management Act, the management plan for extractive waste must be amended if the quantity or quality of the extractive waste or the arrangements for the final treatment or recovery of the waste are substantially changed. Keliber has extractive waste management plans done for Syväjärvi mine, Rapasaari mine and the Päiväneva concentrator area where the TSF is located and for Länttä mine. Reports, in the Finnish language, are: • AFRY Finland Oy 2021: Kaivannaisjätteen jätehuoltosuunnitelma, Rapasaari ja Päiväneva, Hankeversiolle LOMP2021, 5.11.2021, Keliber Technology Oy. • Ramboll Finland Oy 2018: Syväjärven louhoksen kaivannaisjätteen jätehuoltosuunnitelma, 11.4.2018. • Ramboll Finland Oy 2017: Läntän louhoksen kaivannaisjätteen jätehuoltosuunnitelma, 28.11.2017. 16.2.6 Closure Aspects In Finland, a closure plan for a mine is part of the environmental permit application and the plan must be updated as the operation progresses. The final closure plan will be presented to the authorities at the end of the operation. The overall objective of the closure works is to bring the site into as stable a state as possible, both physically and chemically, and in line with the provisions of the legislation and addressing specific requirements of the local environment. At the end of operations, preparation of a closure plan for all activities at each mine site (open pit and underground mine, waste rock and tailings areas) will be done, describing the objectives of the closure and defining the measures to achieve them. Keliber has a conceptual closure plan for the Rapasaari mine and Päiväneva concentrator area where the TSF is located. For Syväjärvi, the closure plan only concerns the waste rock area. Closure reports, in the Finnish language, are: • AFRY Finland Oy 2021: Keliber Oy:n rikastamoalueen ja Rapasaaren kaivosalueen ympäristölupavaiheen sulkemissuunnitelma, Hankeversiolle LOMP2021, 5.11.2021, Keliber Technology Oy. • Envineer Oy 2018: Syväjärven sivukivialueen sulkemissuunnitelma ja sulkemisen kustannusarvio, 19.12.2018, Keliber Oy. On a general level, closure activities comprise the covering of waste rock areas and TSF, making open pits safer by flattening the walls and the demolition of structures unless those can be reused for some other land use activity. The conceptual closure plan for Rapasaari – Päiväneva was developed by AFRY Finland Oy in 2021. The closure plan will be updated during operations and a final closure plan submitted before operations cease and closure commences. The closure plan addresses the impact of closure on surface waters, groundwater, soil, flora and fauna, conservation areas, air quality, landscape, traffic, and people and society. Risks related to closure and controlling measures are listed in the AFRY plan: • The seepage water quantities from the waste rock facilities, TSF and pre-float tailings facility may be larger than estimated and the load of harmful substances greater than anticipated and therefore the impact on soil, groundwater and nearby surface water may be greater than estimated. • Covered waste rock facilities are exposed to erosion. If erosion occurs an increase in water flow through the facilities could mobilize harmful substances. Pyrite-containing rock oxidation may also increase; o Risks can be mitigated by following the precautionary principle in planning and assessment, monitoring during construction and closure, and drainage and monitoring through the quarry lake.
SRK Consulting – 592138 SSW Keliber TRS Page 204 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 • Ramp distortion may damage the cover structure and thus increases risk of contaminant transport which could also pose a hazard to people and animals in the area; o Risks can be controlled by supervision during the construction and closure phases • TSF dam collapse would cause water and tailings discharge into the environment. This may result in the release of contaminants to soil, groundwater, and surface water. (The amount of water in the reservoir will decrease with closure, so the environmental spillage would be less severe than during the production phase.) o Risks can be controlled with dam safety inspections, design and quality control and documentation of design and construction, supervision, and elevations downstream on the excavated embankment. • Rapasaari underground mine water quality may deteriorate the water quality of the quarry lake which can eventually drift to groundwater and to surface waters; o Risk can be controlled by sealing the underground mine to reduce contact with the open pit. • Possible soil contamination not cleaned after operations. Contaminated soil can impact on groundwater and surface waters; o Risks can be controlled during active operations by preventing spills and leakages. Keliber plans to present security deposits of 4.6M€ for Rapasaari mine and 3.4M€ for Päiväneva concentrator. The security deposit is not lodged yet, but Keliber have made provision for it in the financial model (Sheet “Assumptions”, lines 184-191). 16.2.7 Environmental Site Monitoring In Finland the site monitoring will be regulated by the environmental permit decision. An applicant suggests a monitoring plan as part of its permit application. The plan addresses site monitoring during construction works, operations, the closure phase and after closure. The permitting authority issues environmental permit regulations on monitoring according to the plan or, if it is judged to be insufficient, additional monitoring responsibilities can be added. Administration costs for environmental services is 240 k€/year and this is including also environmental site monitoring. At Syväjärvi, monitoring will be done according to the monitoring plan prepared 23.4.2018 (in Finnish: Syväjärven louhosalueen ympäristölupahakemus, which forms appendix 26E2 of the Syväjärvi environmental permit application) and according to regulations issued in the environmental permit and in the Administrative Court decision. For Rapasaari and Päiväneva, a monitoring plan has been submitted to the permitting authority as part of the environmental permit application which was approved on 28 December 2022. When mining operations commence at Syväjärvi and Rapasaari, Keliber aims to combine the separate monitoring plans of these sites. It is common practice in Finland to combine monitoring plans of sites or operations of the same operator. Until Rapasaari and Päiväneva have environmental permits issued and enforced, Syväjärvi will be monitored according to its environmental permit regulations. The environmental permit for Länttä issues regulations on the monitoring of noise, vibration from operations and groundwater and surface water quality Keliber will join with other operators for the monitoring program of the Perhonjoki River area which includes water quality monitoring, diatom, sediment, and fish monitoring. Keliber has joined the air quality bioindicator monitoring program that is in place at the Kokkola and Pietarsaari area. Biodiversity monitoring is presented in the Biodiversity Management Plan. SRK Consulting – 592138 SSW Keliber TRS Page 205 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 16.2.8 Social and Community Aspects Residential surveys have been conducted during the years 2014 – 2018 and the latest survey took place during the EIA process for Syväjärvi, Rapasaari and Outovesi in 2020. Respondents of the 2020 survey were mostly recreational users (33 %), permanent residents (23 %) and others (23 %). A majority of the 98 respondents live within a two-kilometre radius of a project site. The majority of respondents felt that impacts of the Project are positive (43 %). Employment for the Project was perceived to be the most important effect(49 %) and secondly environmental management and sustainable development (42 %). Also, regional development was also seen as a positive impact. On the negative side, respondents saw potential negative impacts to surface waters and possible contamination, damage to natural values and impacts on the ecosystem, dust and noise impacts and possible impacts after closure. What respondents wished from Keliber is that the project commences soon, Keliber should work together with local entrepreneurs and youngsters, the project should stay with Keliber and not be sold to an outsider, engineering with care and caretaking of the environment. Maintaining communication with stakeholders as per the Keliber Stakeholder Engagement Plan, meeting its regulatory commitments, ensuring that it is transparent about both its good and weak performance will all help the Project going forward and managing the social risk. 16.2.9 Recreational Use According to the results of the 2020 residents' survey carried out in connection with the EIA-process, the Syväjärvi, Rapasaari and Outovesi mining areas are considered important for recreational purposes, in particular for hunting, berry picking and mushroom picking. Although, according to public sources, there are no official recreational areas or routes in the mining areas. In stakeholder meetings with local people the recreational use of the areas and the limitation that comes along with mining activities has not been raised as a major issue. Although mining areas limit recreational activities and may cause nuisance in terms of noise and artificial lighting, the areas required by mining are moderate in size. Near the Rapasaari – Päiväneva complex peat production in an area of 350 hectares has been carried out for years resulting in manmade landscape, dust, and noise that already affects recreational use. 16.2.10 Land Use, Economic Activity and Population The industrial structure of Central Ostrobothnia is characterized by the metal, wood, process, and chemical industries. Construction, services, and manufacturing sectors also have a large employment impact. Agricultural production is concentrated in the dairy, beef, and potato sectors. Peat production plays an important role in the energy supply of Central Ostrobothnia. In the hierarchy of the service network in Central Ostrobothnia, Kokkola is the commercial center of the region and Kannus and Kaustinen are sub-centers. It is estimated that mining, concentrator, and chemical plant operations will employ directly 170 and approximately 50 contractors. Keliber will use subcontractors for excavation and transportation. Employment impact was seen as one of the most important positive impacts of the Project. Mining activities and the concentrator plant operations are in accordance with the current regional plan and therefore the project is consistent with and supports the planned land use. Alholmens Kraft (AK) is a significant user of peat and has its own peat production areas at Päiväneva. The Project concentrator plant location is partly on AK’s land. Keliber has purchased areas needed for its operations from AK in a mutual understanding. Forestry at the mining areas will cease and losses have been or will be compensated to owners. Compensation will be paid after establishment of mining area process. The procedure is explained in the Land Acquisition and Livelihood Restoration framework. SRK Consulting – 592138 SSW Keliber TRS Page 206 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Päiväneva is currently not a pristine habitat but an industrial peat production area, which production is coming to an end whereupon the area can be used as a concentrator plant site. Other areas surrounding the Project, mostly peat production and fur farming, can continue in the vicinity despite the mining activities with no adverse impacts (e.g., dust and noise impacts) from mining expected. No other economic activities are known to exist in the Project area which could be significantly affected. The Project is seen to have a positive impact on the region. Some worries about environmental impacts of mining operations have been noted by the public but also trust has been expressed that Keliber will operate in a way that is not harmful to the environment. 16.3 Environmental and social risks There could be potential project delays based on issues related to certain sites, which are being addressed by the project. For example, on the Rapasaari – Päiväneva facilities there were concerns about flying squirrels, which were mitigated in autumn 2021 by moving a proposed tailings facility away from an ancient forest where the squirrels are found. The Outovesi Mine is part of the EIA completed in 2020 (Dnro EPOELY/1102/2020); however, there is no specific environmental permit application underway for the Outovesi Mine. When the environmental permit application for Outovesi is prepared there may be requirements for new environmental studies to be conducted, notably related to groundwater connection between the mine and Outovesi Lake. Keliber is committed to active collaboration and transparent communication with all its stakeholders. The company has a Stakeholder Action Plan and a Grievance Mechanism that is regularly reviewed by the Management Group. Keliber maintains regular ongoing engagement with government, local and regional authorities, landowners and inhabitants, including home and holiday home-owners around Outovesi Lake where potential noise exceedances may occur. Stakeholders are largely supportive of the Keliber Lithium Project as it is seen to have a positive impact on the region in terms of direct and indirect employment opportunities. The ELY authority (the government authority that enforces environmental legislation) has outlined the need for particular attention to be paid to the potential nuisance to holiday homes in the vicinity of the Outovesi mine area where the noise limits may be exceeded according to noise models. Mitigating noise impacts should be well planned and presented in the environmental permit application to avoid holiday homeowners appeals against the permit. Keliber will also consider holiday homeowners in its environmental and social action plan and execution thereof. Keliber has a Land Acquisition and Livelihood Restoration framework which explains the land acquisition process. A rental agreement has been signed for the chemical plant site. Negotiations with landowners for access to the Rapasaari-Päiväneva mining area have already commenced. Keliber is aiming to purchase all land areas of the Rapasaari mine site. All landowners at Syväjärvi mine site have provided written agreement to Keliber granting the right to use the land. The landowners at Syväjärvi who receive compensation for land use rights will also receive excavation compensation. Individual negotiations with landowners either for land use rights or purchase of the land required for the Länttä, Outovesi and Emmes areas are underway and Keliber is confident that it will reach agreement with landowners. If agreement is not reached there is a possibility of the expropriation of land according to Act 603/1977. 16.4 Environmental, social and governance summary All EIA processes including the required statutory stakeholder consultations have been conducted and finalised in terms of the relevant Environmental Law: Environmental Protection Act (527/2014) for the Rapasaari – Päiväneva complex, Syväjärvi, Rapasaari, Länttä and Outovesi mine sites and the Keliber Lithium Hydroxide Refinery. Keliber has met all regulatory permit requirements, except for Outovesi, where the permit is still to be applied for. When the environmental permit application for Outovesi is prepared there may be requirements for new environmental studies to be conducted. The company is in the process of negotiating with landowners for land use rights or purchase of the land for the various mining areas. SRK Consulting – 592138 SSW Keliber TRS Page 207 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 17 CAPITAL AND OPERATING COSTS [§229.601(b)(96)(iii)(B)(18)] SRK reviewed the DFS and classified it as a pre-feasibility study (PFS) in terms of Table 1 to Paragraph (d) in S- K1300 [§229.1302(d)]. This implies Capital Cost Estimate (Capex) and Operating Cost Estimate (Opex) accuracy of ±25% and overall project contingency of ≤15% could be achieved. It should be noted, however, that estimation of capital and operating costs is inherently a forward-looking exercise. These estimates rely upon a range of assumptions and forecasts that are subject to change depending upon macro-economic conditions, operating strategy and new data collected through future operations. Therefore, changes in forward-looking assumptions can result in capital and operating costs that deviate more than 25% from the costs forecast herein. 17.1 Capital cost Keliber presents capital expenditure (capex) as Pre-development and Initial capex and Sustaining capex in the Keliber Lithium Project DFS Report (WSP, 2022). The capital includes the establishment of the open pits, the capital for the Päiväneva Concentrator and the Kokkola LiOH Chemical Plant. The underground mines described in the DFS are not included in the Mineral Reserve and therefore no Capital for the underground mines is reported. All data provided in this chapter is sourced from WSP, 2022 and the updated 18 December 2022 TEM (reference Keliber, 2022). Table 17-1 is a high-level summary of the capex for the project. Table 17-1: Keliber Lithium Project Capital Summary Item Units Total Syväjärvi Mine (EURm) 8.1 Concentrator Plant (Päiväneva Site) (EURm) 156.6 Lithium Hydroxide Plant, Kokkola Site (EURm) 276.3 Engineering & Construction Services (EURm) 48.1 Site Facilities During Construction (EURm) 5.9 Construction Equipment (EURm) 7.2 Other Construction Services And Costs (EURm) 0.7 Owners' Cost (EURm) 23.5 Contingency (EURm) 56.0 Total Initial Capex (EURm) 582.5 (Source: Keliber, 2022) Pre-development capex refers to the initial establishment of the Syväjärvi mine site, the Päiväneva concentrator site and Lithium Hydroxide plant, Kokkola site in preparation for the main construction activities. This includes activities such as surface water management, road construction, architectural work, provision of bulk power supply for the process plants, the EPCM, and Owner’s costs. Direct owner’s costs include property and land acquisitions, construction permits, pre-ramp-up salaries and pre-ramp-up social costs. Indirect Owner’s costs include research and development (R&D), legal and permits, and insurances. Initial capex is expended for the construction of the Syväjärvi Mine, the Päiväneva Concentrator Plant and the Kokkola Lithium Hydroxide Plant. The allocation includes, for direct costs: • Further water management, roads, and overburden removal and storage at Syväjärvi Mine; • Mine electrical, ICT and service infrastructure; • Office and maintenance areas; • Fuel supply and explosive supply areas; and • Päiväneva and Kokkola processing equipment, electrical, ICT, utilities, service infrastructure, buildings, storage facilities, offices, workshops, HVAC, water treatment, water pumping, tanks and reticulation, amongst others. Indirect costs include: • Engineering and construction services, temporary construction facilities, construction equipment, • Services, such as inspections, quality control, office and ramp-up costs; and
SRK Consulting – 592138 SSW Keliber TRS Page 208 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 • Owner’s costs which include, Ramp-up salaries and social costs, R&D, financing, legal and permits, and insurances The pre-development and initial capex schedule is shown in Table 17-2. This capex is due to be expended from H2 2022 until end 2024. Table 17-2: Pre-development and initial capex schedule Item Units Total 2022 2023 2024 2025 Syväjärvi Mine EUROk 8 088 2 681 1 327 4 080 Concentrator Plant (Päiväneva Site) EUROk 156 642 1 805 69 184 73 580 12 073 Lithium Hydroxide Plant, Kokkola Site EUROk 276344 38 386 134 454 90 619 12 886 Engineering & Construction Services EUROk 48 136 3 414 17 862 26 035 825 Site Facilities During Construction EUROk 5 878 199 3 541 1 952 186 Construction Equipment EUROk 7 184 142 3 350 3 642 50 Other Construction Services And Costs EUROk 707 (1 426) 648 1 469 16 Owners' Cost EUROk 23 548 11 823 5 774 5 952 Contingency EUROk 55 951 5 000 25 733 22 294 2 923 Total Initial Capex EUROk 582 478 62 024 261 873 229 623 28 959 (Source: Keliber, 2022) The basis of the capital is described in detail in the WSP Keliber Definitive Feasibility Study Report (reference WSP, 2022) dated February 2022 and follow AACE recommended practice. The estimate has been subsequently revised and re-issued in the November 2022 TEM (reference Keliber, 2022). In SRK’s opinion, the basis for the estimate is appropriate for a prefeasibility study. Sustaining Capex is scheduled to start in H2 2024 and is shown in Table 17-3 Sustaining Capital is all capital from 2024 onward and includes the sustaining capital for the concentrator and the Chemical Plant, the establishment and stay-in-business capital for the open pit mines (Rapasaari, Länttä, and Outovesi), as well as closure provisions. SRK Consulting – 592138 SSW Keliber TRS Page 209 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Table 17-3: Keliber Lithium Project sustaining capital schedule Sustaining Capital Units Total 2024 2025 2026 2027 2028 2029 2030 2031 to 2047 Syväjärvi Mine EUROk 3 086 1 414 616 1 056 Overburden Removal EUROk 1 414 1 414 Closure EUROk 1 672 616 1 056 Rapasaari Mine EUROk 25 333 6 647 3 813 4 766 1 686 3 794 4 627 Rapasaari Mine Site Area EUROk 20 705 6 647 3 813 4 766 1 686 3 794 Closure EUROk 4 627 4 627 Länttä Mine EUROk 1 799 1 799 Länttä Mine Site Area EUROk 1 471 1 471 Closure EUROk 328 328 Outovesi Mine EUROk 2 973 2 973 Outovesi Mine Site Area EUROk 2 535 2 535 Closure EUROk 438 438 Concentrator Plant (Päiväneva Site) EUROk 42 902 4 994 17 539 5 591 320 291 3 078 11 090 Päiväneva Site Area EUROk 31 228 3 583 14 717 5 511 2 816 4 602 Concentrate Building EUROk 8 282 1 411 2 822 80 320 291 262 3 096 Päiväneva Closure EUROk 3 392 3 392 Lithium Hydroxide Plant, Kokkola Site EUROk 37 707 1 000 3 822 3 411 822 1 233 1 233 3 233 22 954 Production Building LHP EUROk 23 550 2 822 1 411 623 935 935 935 15 890 Kokkola Site Area EUROk 8 000 1 000 1 000 2 000 2 000 2 000 Calcinating Area EUROk 6 157 199 298 298 298 5 064 Total EUROk 110 828 1 000 10 230 27 597 10 225 6 318 3 826 11 160 40 471 (Source: Keliber, 2022) 17.2 Operating costs Keliber has prepared the operating cost estimates in collaboration with Afry, Sweco, FLSmidth and Metso- Outotec. The operating cost estimate is divided into seven different areas: • Mining; • Päiväneva Concentrator; • Kokkola Conversion and Lithium Chemical plant; • Other variable costs; • Freight and Transportation; • Fixed costs; and • Royalties and Fees. 17.2.1 Mining cost The OP mining costs vary between the mining areas and at depth. The average waste direct mining unit cost varies between USD2.67/t and USD5.31/t and the average ore direct mining unit cost varies between USD3.74/t and USD9.51/t, based on contractor quotes from the 2019 FS which has been increased by 25% and seem a reasonable assumption at this stage. The unit costs for OP mining (excluding processing) and accounting for the planned stripping ratios averages USD26/t ore mined. The OP mining parameters are summarized in Table 17-4. SRK Consulting – 592138 SSW Keliber TRS Page 210 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Table 17-4: Open pit mining optimisation parameter summary Description Unit Rapasaari Syväjärvi Länttä and Outovesi Exchange Rate EUR/USD 1.21 1.1 1.1 Price (LiOH.H2O t) USD/t 14 128 Price (LiOH.H2O t) USD/t EUR/t 2022 13 450 11 116 2023 13 250 10 950 2024 15 000 12 397 2025 16 500 13 636 2026 15 300 12 645 2027 15 200 12 562 2028 15 100 12 479 2029 14 200 11 736 2030 14 800 12 231 Price (Li2CO3) EUR/t 9 918 Total Fees and Royalties EUR/t 1.69 Discount Rate % 8 8 8 Modifying Factors Dilution (Including Internal Waste) % 19.5 14.2 0 Mining Losses % 95 95 95 Cut -Off Grade % 0.4 0.5 0.5 Geotechnical Overall slope angle East Degrees 37º 49º Overall slope angle West Degrees 41º Overall slope angle East and other areas Degrees 47º 45º to 50º Mining Costs Waste Mining EUR/t 1.85 Ore Mining EUR/t 3.22 Additional Bench Costs Waste Mining EUR/t 0.19 0.17 0.17 Ore Mining EUR/t 0.11 0.17 0.17 Blasting EUR/t Waste Mining EUR/t 1.19 1.19 Ore Mining EUR/t 1.6 1.6 Ore loading and haulage per km EUR/t 1.54 1.54 Waste rock loading and haulage per km EUR/t 1.43 1.43 Ore loading to Kaustinen and first haulage kilometre EUR/t 1.25 1.25 Each additional 1 km of ore haulage to Kaustinen EUR/t 0.15 0.15 Additional cost to mine Fe-sulphide bearing mica schist EUR/t 3.5 0 Fixed Cost (Processing Labour) 4.8 Processing Costs EUR/t 45 51.5 57 Global Lithium Yield % 74.30% 74.50% Länttä % 67.10% Outovesi % 73.10% The UG costs on which the Mineral Resource cut-off grade is based (USD21.2/t) are based on contractor quotes and would appear to be a reasonable assumption at this stage. SRK Consulting – 592138 SSW Keliber TRS Page 211 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 17.2.2 Concentration and lithium hydroxide production costs Lithium hydroxide production of 316 287 tonnes is planned over the life of the Project. This includes 96 000 tonnes from external concentrates purchased over 6 years (Jan-42 to Dec-47) after depletion of the mine mineral reserves. Production from Keliber’s own spodumene concentrate is estimated at 220 287 tonnes LiOH.2H2O. Non-mining costs for production of lithium hydroxide from Keliber’s own concentrate are summarised in Table 17-5. These include 10% contingency applied to most elements. Table 17-5: Non-mining cost summary Section Cost Element LoM Cost (kEUR) LoM Unit Cost (EUR/t LiOH.H2O) Crushing & Sorting Crushing, Sorting & Stockpiling 6 606.86 29.99 Concentrator Energy 31 890.93 144.77 Reagents 66 166.66 300.36 Consumables 31 847.25 144.57 Maintenance 17 303.67 78.55 Concentrator Water Treatment Energy 3 495.74 15.87 Reagents 8 541.38 38.77 Consumables 1 758.84 7.98 Maintenance 1 329.30 6.03 Concentrate Loading & Transport 22 307.23 101.26 Concentrate Purchase - - Conversion Energy/Fuel 70 771.76 321.27 Other Consumables / Utilities 9 228.65 41.89 Lithium Hydroxide Plant Energy 68 526.97 311.08 Steam 86 832.14 394.18 Reagents 220 958.61 1 003.05 Process Water 2 185.75 9.92 Consumables 4 526.81 20.55 Utilities 12 327.55 55.96 Maintenance 16 536.49 75.07 LHP Water Treatment Reagents 17 238.02 78.25 Consumables 8 308.18 37.72 Energy 1 574.56 7.15 Other Costs 3 395.03 15.41 Other Variable Costs Service & Handling 1 823.32 8.28 Other Costs 550.28 2.50 Transport & Packing Side Rock Transport - - Final Product Transport 14 725.61 66.85 Processing Labour Labour Costs 161 365.31 732.52 Other Operating Costs District Heat 20 748.92 94.19 Subtotal Cost of Goods Sold 1 322 618.58 6 004.06 SG&A General & Administration 139 880.60 634.99 Property-related Costs 8 873.53 40.28 Others 5 588.99 25.37 Royalties & Fees Royalties 5 944.85 26.99 Fees 11 010.27 49.98 TOTAL 1 493 916.81 6 781.67 17.2.3 Päiväneva Concentrator (crushing, sorting and concentration) Ore from the mine will be hauled to the primary crusher located at the Päiväneva concentrator. Primary crushing and sorting costs are then applied to the concentrator area. The operating cost of the concentrator plant includes energy, reagents, consumables, and maintenance. The same items are covered for the water treatment plant which is considered as being part of the concentrator site area.
SRK Consulting – 592138 SSW Keliber TRS Page 212 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Energy is calculated based on the electrical load list of the equipment and the estimated power consumption. Reagents are derived from the process reagent consumption and costs are estimated from quotations provided by reagent suppliers. Consumables and maintenance costs were estimated based on recommendations derived from concentrator basic engineering work completed by Metso Outotec. Concentrator operating cost for the life of the project is estimated at EUR168.9m or EUR 767/t LiOH.H2O produced from Keliber Lithium Project’s concentrates. 17.2.4 Keliber Lithium Hydroxide Refinery (conversion and LHP production) Operating costs of the Kokkola Chemical Plant are estimated at EUR544.7m or EUR 2 473 /t of LiOH.H2O produced from Keliber Lithium Project’s concentrates. The main contributors to the costs are energy, steam generation and reagents. 17.2.5 Other variable costs Other variable costs contribute EUR2.4m or EUR 11 /t of LiOH.H2O to overall operating costs. 17.2.6 Freight and transportation Freight and transportation costs contribute EUR14.726m or EUR 67 /t of LiOH.H2O to overall operating costs. 17.2.7 Fixed costs Fixed costs include labour costs, LNG connection fees, LHP connection fees, various water retainer fees, fixed operating costs for heating of buildings, laboratory running costs, property related costs, utility system and G&A costs. These fixed costs are estimated at EUR 336.5m or EUR 1 527 /t of LiOH.H2O produced over the life of the mines, with labour and G&A costs comprising 48% and 42% respectively. 17.2.8 Royalties and fees Royalties and fees contribute EUR17.0m or EUR 77/t of LiOH.H2O produced to overall costs. SRK Consulting – 592138 SSW Keliber TRS Page 213 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 18 ECONOMIC ANALYSIS [§229.601(b)(96)(iii)(B)(19)] The financial model is premised on open pit production rates and processing plant performance as defined in the Keliber FS. The concentrate can be sold on the open market for which forecast prices are available. The Mineral Reserves for Keliber have been declared on the basis that a ready market exists for the concentrate and the NPV is positive, without the need for a refinery. The feed to the concentrator is limited to the open pit ore that comprises the Mineral Reserve. The schedule is graphically illustrated in Figure 18-1. As described earlier, the company DFS planned to supplement the feed with underground ore. The schedule has not been optimised for open pit ore. Keliber Mine and Concentrator Feed to Plant by Source Project No. 592138 Figure 18-1: Keliber Mine and Concentrator Feed by Source Plant recovery is a critical success factor. The factors that drive recovery are discussed in detail in the mining and processing sections and are not repeated here. The financial performance is reliant on the efficiency of the ore sorting, both through removal of waste and ensuring that there is no loss of contained lithium. During the period when Keliber is operating as a vertically-integrated Mine, Concentrator and Refinery, the concentrate grade will be adjusted to optimise the overall economics. In this hypothetical case, a concentrate grade has been estimated to feed into the third-party concentrate market. Although a 4.5% spodumene concentrate is not a typical product, according to Wood Mackenzie (2021) and Fastmarkets March (2022), there is a demand for this product in Europe and this particular concentrate is appealing to glass manufacturers due to the low iron content. See Chapter 15 (Market Studies) for a detailed description of the commodity pricing and demand for the 4.5% spodumene concentrate. The potential premiums for the product and the low impurities are considered to offset the discount that could be applied for the lower product concentration (25% reduction). The spodumene concentrate grade can be increased to 6% but this would introduce other uncertainties given that the detailed work has been done on the 4.5%, which is considered optimal for the integrated business. The feed to the plant is driven by the production from the open pit sources. No changes have been made to the DFS schedules developed, the underground tonnes have just been omitted from the schedule. This is obviously not optimal but, absent a specific study to confirm new numbers, it is not possible to be certain that a new schedule would be achievable. SRK Consulting – 592138 SSW Keliber TRS Page 214 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 The concentrate production is as per the detailed DFS financial model but limited to the open pit ore. This directly drives the revenue along with the forecast price. The costs are based on the DFS but adjusted to reflect the lower tonnages for the periods where the underground tonnes are excluded. The economic analysis is inherently a forward-looking exercise. These estimates rely upon a range of assumptions and forecasts that are subject to change depending upon macro-economic conditions, operating strategy and new data collected through future operations. The economic assessment described here is premised on a prefeasibility study that exploits only Mineral Reserves. There is no certainty that this economic assessment will be realized. The final cash flows presented are summarised cash flows. Detailed analysis of the mining and processing costs are presented in the respective sections. SRK Consulting – 592138 SSW Keliber TRS Page 215 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Table 18-1: Mine and Concentrator Only with scheduled Mineral Reserve Description Total 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 OP Ore to Crusher (kt) 9 476 - - 472 718 700 735 755 692 718 757 762 696 673 676 598 175 322 28 Spodumene Concentrate Produced (kt) 1 637 - - 13 136 157 156 139 135 135 134 116 102 113 109 87 28 69 8 Revenue (EURm) Lithium (Spodumene) 1 531 - - 26 198 138 137 122 118 118 118 102 90 99 96 76 24 61 7 Costs (EURm) Landowner Payments (Fees) 16 0.2 0.3 0.8 1.1 1.2 1.2 1.3 1.1 1.1 1.0 1.0 1.0 1.0 1.0 1.1 0.9 0.6 0.6 Central Allocated Costs (Total SG&A) 58 1.7 2.0 3.4 3.5 3.4 3.4 3.4 3.4 3.4 3.4 3.4 3.4 3.4 3.4 3.4 3.4 3.4 3.4 Processing 51 - - 0.6 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3 3.3 Mining Costs 422 - - 10.4 30.4 31.9 31.6 30.2 31.3 31.9 37.0 43.6 37.9 26.3 25.8 27.8 8.4 16.4 1.3 Lithium Spodumene Shipment to Antwerp 102 - - 0.7 6.8 7.9 7.8 6.9 6.7 6.7 6.9 6.2 6.3 6.9 6.7 5.9 6.5 7.2 5.5 Total Working Costs (EURm) 649 2 2 16 45 48 47 45 46 47 52 58 52 41 40 42 23 31 14 Revenue less Total Working Costs (EURm) 882 -2 -2 10 153 91 90 77 72 72 66 44 38 58 55 35 2 30 -7 Renewals and Replacements 43 - - - - - 6.4 17.5 5.6 0.3 0.9 4.1 0.8 2.7 1.2 0.3 2.8 0.3 0.3 Allocated Capital Expenditure 228 81.7 112.3 34.2 - - - - - - - - - - - - - - - Total Capital Expenditure (EURm) 272 82 112 34 - - 6 18 6 0 1 4 1 3 1 0 3 0 0 Revenue less Total Working Costs and Capital 610 -84 -115 -24 153 91 84 59 67 71 65 40 37 56 54 35 -1 30 -8 Total Other Expenditure (EURm) - - - - - - - - - - - - - - - - - - - Operating Profit before Taxes (EURm) 610 -84 -115 -24 153 91 84 59 67 71 65 40 37 56 54 35 -1 30 -8 Royalties 6.3 - - 0.2 0.4 0.3 0.4 0.4 0.3 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 Taxation 170 - - - 24.7 18.0 17.9 15.3 14.4 14.3 13.2 8.7 7.5 11.6 11.0 6.9 0.2 5.9 - Free Cash Flow (EURm) 434 -84 -115 -24 128 72 65 44 52 57 52 31 29 44 43 27 -2 23 -8 NPV (EURm) 136
SRK Consulting – 592138 SSW Keliber TRS Page 216 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date:13 December 2023 Effective Date: 31 December 2022 The taxes and royalties and payments that are required to landowners based on various agreements and legislation are incorporated into the model. A detailed breakdown is provided in an earlier chapter on the basis for the taxes, royalties and landowner payments. A two-factor sensitivity for revenue and total operating costs was also developed. The results are shown in Table 18-4. The project NPV is most sensitive to price, as is expected. It is important to note that the same sensitivity applies to exchange rate given that the costs are in euros and the revenue in dollars. Thus, a 5% change in exchange rate will have the same impact as a 5% change in price. The sensitivity for exchange rate is not shown as it is an exact replica of the price sensitivity. Table 18-2: Sensitivity of NPV to Revenue and Working Costs NPV in EURm Long-term concentrate price (USD/t) 834 886 938 990 1 042 1 094 1 146 1 198 1 250 84.7 -20% -15% -10% -5% 0% 5% 10% 15% 20% Working Costs (EUR/t) 61.7 -10% 39 69 100 130 160 190 221 251 281 65.1 -5% 27 58 88 118 148 179 209 239 269 68.5 0% 15 46 76 106 136.4 167 197 227 257 71.9 5% 3 34 64 94 124.5 155 185 215 245 75.4 10% -8 22 52 82 113 142.8 173 203 234 A further sensitivity was developed for the discount rate. The base case discount rate has been selected as 10% as per the Sibanye-Stillwater policy for projects. Table 18-3: Sensitivity to Discount Rate Discount Rate NPV (EURm) (USDm) (ZARm) 6.0% 223 239 4 058 8.0% 176 188 3 198 10.0% 136.4 145.8 2 478 12.0% 103 110 1 872 14.0% 75 80 1 358 SRK has placed reliance on Sibanye-Stillwater for the market analysis and the price and exchange rate forecasts. The company makes use of the UBS forecasts. UBS survey several analysts for their views on the spodumene concentrate and lithium hydroxide prices. The December 2022 forecasts have been used, the latest available at the Effective Date. The average of the surveyed analysts is used for the company financial models and is used in these models. The price and exchange rate forecasts used are shown in Table 18-6: Table 18-4: Price and Exchange Rate forecasts Price and Exchange Rate forecasts 2023 2024 2025 2026 LTP Lithium (Spodumene) USD/t 4 971 3 638 2 297 1 730 1 042 Lithium (Hydroxide) USD/t 55 746 41 490 30 054 23 203 15 195 EUR:USD 0.95 0.90 0.89 0.89 0.89 Note that the EUR:USD exchange rate has used the 2025 forecast for the long-term rate as there were fewer analysts who forecast the later years. The analysts who did forecast expected further weakening, which would improve the project economics by effectively increasing the dollar-based revenue without increasing the euro- based costs. The Consensus Economics forecasts were also consulted. The Consensus Economics view is that the long-term lithium hydroxide price will be slightly higher than that used in the integrated model but that the long-term spodumene concentrate price will be slightly lower. The average operating margin for the life of mine is 42%. The risk of a negative operating margin is considered low, and the project capital required has been funded. Additional funds are available if required. This means that SRK Consulting – 592138 SSW Keliber TRS Page 217 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date:13 December 2023 Effective Date: 31 December 2022 the company is in a position to complete the project and that the project would operate on a cash positive basis under most foreseeable price paths, even though the NPV might vary dramatically. The post-tax NPV of the project is forecast to be EUR136m at a 10% real discount rate and with a forecast IRR of 21.5%. The mine and concentrator are predicted to have a payback period of approximately 5 years. SRK Consulting – 592138 SSW Keliber TRS Page 218 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date:13 December 2023 Effective Date: 31 December 2022 19 ADJACENT PROPERTIES [§229.601(b)(96)(iii)(B)(20)] The Keliber Lithium Project is the most advanced lithium project in the region. It is likely that there is potential for identification and exploration of additional similar orebodies in the region, including under the current Keliber license areas, however there are no other lithium exploration licenses held by other companies surrounding the Keliber license areas. SRK Consulting – 592138 SSW Keliber TRS Page 219 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date:13 December 2023 Effective Date: 31 December 2022 20 OTHER RELEVANT DATA AND INFORMATION [§229.601(b)(96)(iii)(B)(21)] 20.1 Project Implementation A project implementation plan was prepared by Sweco Oy (Sweco) for the establishment of the Syväjärvi Mining site, Päiväneva concentrator site and Kokkola LiOH plant. These sites comprise the initial capital footprint. Keliber has selected Sweco as an EPCM (Engineering, Procurement and Construction management) contractor to supply services for the project implementation. Services of the EPCM contractor includes, in accordance with the responsibility matrix, project management, procurement services, project control, process, mechanical, piping, civil, HVAC, electrical and automation engineering and construction management. Sweco has produced a comprehensive Project Execution Plan originally drafted in August 2021 and updated a number of times, with the latest update in Feasibility Study of January 2022. The updated milestone dates in Table 20-1 below were developed from the information containing in the Keliber Financial Model dated 18 December 2022 and an update email dated 3 March 2023 with a schedule for the Kokkola LiOH Plant provided by Keliber. The project implementation plan does not currently include the later mines. SRK assumes that detailed implementation plans for these will be developed in due course. Key milestone dates on 6 March 2023 are shown in Table 20-1 with notes below. Table 20-1: Project Milestones Milestone Milestone date Kokkola LiOH Plant - start of site clearing February 2023(2) Kokkola LiOH Plant – Mechanical Completion March 2025(2) Kokkola LiOH Plant – Final Acceptance December 2025(2) Päiväneva Concentrator - start of earthworks To be determined(3)(4) Päiväneva Concentrator - cold commissioning completed To be determined(4) Syväjärvi Mine - start of roads, wetland treatment To be determined(3) Syväjärvi Mine – first ore To be determined(3) Start of Sustaining capex November 2024(1) End of Initial capex July 2025(1) Rapasaari Mine - start of site work - open pit To be determined(3)(5) Rapasaari Mine – First ore To be determined(3)(5) (Sources: Keliber, 2022 and Keliber, 2023a) Notes to Table 20-1 (Source Keliber 2023a): 1. According to the Keliber Financial Model dated 18 December 2022; 2. According to the Target Master Schedule for the Kokkola LiOH Refinery Project, (5 January 2023) 3. The Syväjärvi and Rapasaari mines, and Päiväneva concentrator plant schedule is not up to date currently, confirmed start dates are not available; 4. Duration of key milestones at Päiväneva are roughly the following: a. Crushing, Mechanical completion and start of hot commissioning; 22 months after construction start; b. Complete plant, Mechanical completion and start of hot commissioning; 24 months after construction start; c. Taking over, 27 months after construction start (plant is operational); and d. Final acceptance 33 – 34 months after construction start (full capacity). 5. Syväjärvi pit needs to be operationally ready when the Päiväneva Concentrator crushing line hot commissioning starts i.e., 22 months after construction start. In the Feasibility Study, Rapasaari production was planned to start about a year later.
SRK Consulting – 592138 SSW Keliber TRS Page 220 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date:13 December 2023 Effective Date: 31 December 2022 20.2 Exploration Programme and Budget [12.10(e)(i)-(iii), 12.10(h)(vi)], SR3.1(i)-(vi), SR 3.2(i)] Currently, Keliber has an exploration budget for the next three years, 2023 - 2025. The exploration budget for 2023 is EUR 4.3 million. It is estimated that the annual exploration budget can be increased to EUR 6.7 – EUR 7.3 million in 2024 - 2025, if the exploration returns good results. A total of 26 000 m is planned to be drilled in 2023. Drilling will be focused especially on the Rapasaari, Tuoreetsaaret, Syväjärvi and Päiväneva target areas. The Rapasaari and Syväjärvi deposits are the largest of the known deposits and the most advanced in exploration and are scheduled for first mining in the current engineering studies. Tuoreetsaaret is located between Rapasaari and Syväjärvi and represents an opportunity to extend the early production from these two deposits from a nearby source. The continued exploration in this area aims to improve the confidence in the Tuoreetsaaret deposit and to extend the Mineral Resources at Tuoreetsaaret and in the surrounding areas. Päiväneva is the most advanced of a number of targets in the region and is the initial target for expanding and extending the Mineral Resource base in the region. Most of the planned drilling (~15 600 m) is aimed as existing deposits as described above to secure the business case and expand the life of mine, with a further ~5 200 m targeted at brownfields exploration. Exploration for new targets is planned with ~4 000 m, and approximately 1 300 m planned for sterilisation drilling under the expended footprint of the waste rock dump. Geochemical exploration will also be conducted using percussion drilling methods to obtain samples from the bedrock surface as well as from the basal till. Additional work will include boulder mapping, surface till sampling and Mineral Resource estimations. SRK considers the budget to be appropriate. 20.3 Risk review 20.3.1 Introduction The following section presents the key interpretations for the risk review for Keliber. The risk review considered documents provided by SSW, as well as information available in the public domain. 20.3.2 Overview of specific risk elements The available information for the project identifies and/or points to the following risk-related issues: 20.3.2.1 Tenure Currently, there are three mining permits in place (i.e., Länttä , Syväjärvi and Rapasaari) and a number of applications have been submitted (as well as prepared, pending submission) for exploration and mining permits. However, there is some uncertainty regarding the time required for the authorities to process the applications. It is understood that Keliber is completing a legal due diligence exercise to understand the permitting risks. The resolution of this risk is not required for the declaration of Mineral Resources. Public perception of potential environmental impact related to mining appears to be changing. Uncertainty regarding potential objections by the public and/or authorities to the award of tenure for each of the applications exists. The relevance of the uncertainty is that the current project does not appear to have considered scenario models if some of the applications, or specific applications, are either significantly delayed or are wholly unsuccessful. 20.3.2.2 Geology The style of mineralisation is similar between the deposits, and they are all in relatively close proximity. The continuity of the larger veins in all five of the deposits is demonstrated to be good during the geological modelling, with relatively uncomplicated morphology. Therefore, the risk that the veins as modelled are discontinuous, is considered to be low. 20.3.2.3 Water management Significant water bodies are present at the Syväjärvi and Emmes deposits and would require careful management. Flow rate modelling parameters need to be carefully considered to accurately determine the amount of fresh water available and potential impacts on downstream water quality need to be carefully investigated. SRK Consulting – 592138 SSW Keliber TRS Page 221 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date:13 December 2023 Effective Date: 31 December 2022 20.3.2.4 Mineral Resource estimation The overall Mineral Resource estimation has been conducted in line with the guidelines of international reporting codes. The classification of the individual veins reflects the uncertainty, and therefore the degree of risk, in achieving the estimated tonnes and grades from the respective ore bodies. 20.3.2.5 Rock engineering Geotechnical conditions vary across the different sites, with open pit reserves having higher geotechnical data confidence due to existing exposures and laboratory test work. Focus is required on discontinuity strengths and structural data confidence in particular to further enhance design confidence. It is expected that rock engineering data collection and processing will be expanded as the project develops to allow for rigorous assessment of the rock engineering risks across the respective sites. Paucity of geotechnical data, including rock mass strength and characterisation data, as well as confidence in structural geology models, result in conservative design and risk assumptions and potential for the associated unknown ground conditions. 20.3.2.6 Metallurgical processing Based on pilot-scale XRT ore sorting test results conducted on Syväjärvi ore samples, it was concluded that ore sorting is 73% efficient. There is a risk that ore sorting efficiency will vary across the Syväjärvi deposit. It was further assumed that the same efficiency would apply to other ore sources and ore types. There is a risk that other deposits will not perform with the same efficiency. The feed to the ore sorting test equipment comprised an artificial blend of Syväjärvi ore and waste rock. There is a risk that performance on mined ore may be less efficient than on the artificial composite ore feed. Ore variability flotation tests undertaken on Rapasaari samples selected from four different mineralised material types showed significant variability. There is a risk that flotation performance will vary within and across the various deposits. Despite spodumene mineralisation being generally homogeneously distributed throughout most of the pegmatites, the contamination caused by the inclusion of host rock xenoliths and wall rock material with ore material will impact the metallurgical recovery of spodumene during flotation and metallurgical processing. This will require careful selective mining supported by ore sorting to mitigate the impacts of contamination on the recovery of spodumene. The Keliber project is likely to be the first implementation of the Metso Outotec lithium hydroxide flowsheet. While the individual unit processes are not novel, and while the Syväjärvi (2020) and Rapasaari (2022) pilot trials have significantly de-risked the flowsheet, a residual risk remains, as it does with the first example of any novel technology. Potential concerns were noted that the processing plant may not cope with the arsenic levels from Rapasaari material, which may lead to LiOH product falling to technical grade. 20.3.3 Potential economic impact of COVID-19 The Covid-19 global pandemic presented suddenly and with immense impact. Management measures on an international, national and local scale were developed in response by relevant authorities and varied in the potential for downstream effects (e.g., restriction of movement of people and/or materials, delays in new activities due to backlogs, etc.). There is some uncertainty of the effect from the continued, albeit modified, Covid-19 measures on developing the project (in terms of the larger context). Similarly, an unexpected repeat incidence or emergence of a new global crisis could affect the development of the project. 20.3.4 Opportunities The inclusion of Keliber into the SSW’s Battery Metals assets portfolio and battery metals strategy is an important step in acquiring further downstream exposure to the battery metals value chain. Lithium hydroxide (a chemical needed in the production of the cathode active material in modern high-nickel cathode materials, which provide higher energy density) is expected to become the dominant lithium chemical SRK Consulting – 592138 SSW Keliber TRS Page 222 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date:13 December 2023 Effective Date: 31 December 2022 consumed in battery applications. In the future, Keliber will offer lithium hydroxide especially for the needs of the strongly growing lithium battery market. The battery-grade lithium hydroxide produced can be used for the manufacturing of batteries for increasingly electrifying transport (electric and hybrid vehicles) as well as in the production of batteries for energy storage. SRK Consulting – 592138 SSW Keliber TRS Page 223 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date:13 December 2023 Effective Date: 31 December 2022 21 INTERPRETATION AND CONCLUSIONS [§229.601(b)(96)(iii)(B)(22)] In January 2022, Keliber issued a draft Definitive Feasibility Study (DFS) (WSP Global Inc., 2022c) based on the production of 15 000 tpa of battery-grade lithium hydroxide. This DFS used the DFS issued in February 2019 as basis for most of the technical work. The final DFS was issued on 1st February 2022. SRK reviewed this DFS and classified it as a pre-feasibility study (PFS) in terms of Table 1 to Paragraph (d) in S-K1300 [§229.1302(d)]. This implies Capital Cost Estimate (Capex) and Operating Cost Estimate (Opex) accuracy of ±25% and overall project contingency of ≤15% could be achieved. It should be noted, however, that estimation of capital and operating costs is inherently a forward- looking exercise. These estimates rely upon a range of assumptions and forecasts that are subject to change depending upon macro-economic conditions, operating strategy and new data collected through future operations. Therefore, changes in forward-looking assumptions can result in capital and operating costs that deviate more than 25% from the costs forecast herein The major reasons for the downgrade of the DFS to PFS level by SRK are as follows: • The mining cost for the February 2022 DFS was derived by escalating the February 2019 DFS’s mining cost by 25%, The RFQ’s were thus not updated for the February 2022 DFS. • Geotechnical test work was not done to DFS level; o Geotechnical drilling and testwork was limited to the Rapaasari mining property; and o Geotechnical data from the Rapasaari deposit was used to infer geotechnical parameters for the other operations. • The Keliber concentrator will make use of XRT ore sorting to remove waste material from mill feed; o This was only tested on Syväjärvi mining property ore material; ▪ The characteristics across the mining property may vary which was not tested; and ▪ The efficiency results from the tests were assumed for other mining properties. • The Market for concentrate of 4.5% Lithium spodumene is unknown as the benchmark is 6% Li2O in Europe. 21.1 Geology, exploration, sampling and Mineral Resources All of the pegmatites that have been discovered and evaluated to date within the Kaustinen area have very similar mineralogy, and are dominated by albite, quartz, K-feldspar, spodumene and muscovite. The rare element pegmatites belonging to the Kaustinen lithium province belong to the LCT group of pegmatites. They also belong to the albite-spodumene subgroup based on the pegmatites’ high spodumene and albite content. The presence of numerous granites (many being pegmatitic granites) in the Kaustinen area are thought to be the potential sources of the pegmatites, although there has been no clear or well-defined zonation observed to date to prove this. Apart from data generated from overburden stripping at Länttä and the exploration tunnel in Syväjärvi, diamond core drilling has been the only method used to generate geological, structural and analytical data and these have been used as the basis for Mineral Resource estimation over each of the deposits defined to date. Keliber has been following a well-defined logging, sampling and analytical procedure since 2014. The sampling and core storage facility in Kaustinen is considered a secure facility with the sample preparation and analytical methodologies considered appropriate for the commodity being evaluated (lithium). SRK concludes that the sample database is of sufficient quality and accuracy for use in Mineral Resource estimation. Since commencement of exploration in the Kaustinen region, Keliber has completed a systematic exploration and mineral resource evaluation programme that has been successful in delineating five discrete spodumene- mineralised pegmatite deposits. The work completed to date has captured all the important variables (mineralogical, structural, lithological) required to properly define the attitude of the host pegmatite/s and importantly, the spodumene or grade distribution within the various pegmatites that host each deposit. In SRK’s opinion the exploration data that has been captured to date (consisting primarily of drilling data) is of sufficient quality to be used in Mineral Resource estimation and for the purposes used in this TRS.
SRK Consulting – 592138 SSW Keliber TRS Page 224 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date:13 December 2023 Effective Date: 31 December 2022 The Mineral Resources have been estimated using conventional industry standard techniques, and the continuity of the modelled veins has been adequately demonstrated through the wireframe modelling, which supports the lateral and down-dip continuity of the mineralised veins. The Mineral Resources have been appropriately classified with respect to the confidence in the data, interpretation, and the vein and grade continuity. Currently, Keliber has an exploration budget for the next three years, 2023 - 2025. The exploration budget for 2023 is EUR4.3m. It is estimated that the annual exploration budget can be increased to EUR6.7 - EUR7.3 in 2024 - 2025, if the exploration returns good results. A total of 26 000 m is planned to be drilled in 2023. Drilling will be focused especially on the Rapasaari, Tuoreetsaaret, Syväjärvi and Päiväneva target areas. Geochemical exploration will also be conducted using percussion drilling methods to obtain samples from the bedrock surface as well as from the basal till. Additional work will include boulder mapping, surface till sampling and Mineral Resource estimation. SRK considers the budget to be appropriate. 21.2 Geotechnical testing Each core sample specimen for UCS and indirect tensile tests (Brazilian) (BR) was prepared according to ISRM (2006) suggested methods. The suggested length was 2 - 3 drill core diameters and rock samples were split into five groups according to their rock type. Foliation parameters of recognized volcanic and sedimentary units were estimated. While the rock strength test work carried out aligns with standard testing techniques, joint shear strength areas analyses must still be done. Review of the previous reports did not show soil testing results, nor the testing methods carried out. Additionally, the coordinated location of where the samples were collected could not be verified. No reference to QA/QC procedures on the laboratory test work results was made in previous reports. 21.3 Metallurgical testing and mineral processing Keliber mineral processing is complex, including conventional and novel unit processes aimed at producing a high purity product. Further complexity is added by the need to process ore from four deposits from diluted open pit operations. 21.3.1 Ore beneficiation Ore beneficiation at the Päiväneva concentrator includes crushing, grinding, ore sorting, low intensity magnetic separation, desliming and flotation ahead of dewatering and filtration of concentrate for despatch by road to the Keliber Lithium Hydroxide Plant. Crushing, grinding and flotation are conventional unit processes and, with certain exceptions, are reasonably well understood based on bench and pilot-scale test results. Based on pilot-scale XRT ore sorting test results conducted on Syväjärvi ore samples, it was concluded that ore sorting is 73% efficient. There is a risk that ore sorting efficiency will vary across the Syväjärvi deposit. It is accordingly recommended that ore sorting variability tests be conducted across the Syväjärvi deposit. It was further assumed that the same efficiency would apply to other ore sources and ore types. There is a risk that other deposits will not perform with the same efficiency. It is accordingly recommended that these deposits be subjected to pilot ore sorting and variability tests using XRT ore sorting technology. The feed to the ore sorting test equipment comprised an artificial blend of Syväjärvi ore and waste rock. There is a risk that performance on mined ore may be less efficient than on the artificial composite ore feed. It is accordingly recommended that samples of mined ore from all deposits be subjected to pilot ore sorting tests using XRT ore sorting technology. Overall, it was shown that the higher the waste rock dilution ratio the lower the Li2O grades and flotation recovery. Ore variability flotation tests undertaken on Rapasaari samples selected from four different mineralised material types also indicated spatial variability. Further investigation would be required on all other deposits to ensure adequate understanding of spatial variability in flotation performance. 21.3.2 Chemical processing The Keliber Lithium Hydroxide Plant includes pyrometallurgical conversion of alpha-spodumene to beta- spodumene ahead of hydrometallurgical production of lithium hydroxide. Conversion of alpha-spodumene to beta-spodumene occurs in a direct heated rotary kiln fired with Liquified Petroleum Gas. SRK Consulting – 592138 SSW Keliber TRS Page 225 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date:13 December 2023 Effective Date: 31 December 2022 The hydrometallurgical process includes primary sodium carbonate leaching in an autoclave ahead of cold conversion of lithium carbonate to lithium hydroxide. Leach solution containing lithium hydroxide is fed through polishing filters ahead of ion exchange to remove elements such as calcium and magnesium. Lithium hydroxide is crystallised from the lithium hydroxide solution by means of pre-evaporation in a mechanical vapour recompression (MVR) falling film evaporator, followed by an MVR crystalliser. Lithium hydroxide slurry from the crystallisation stage is fed to a centrifuge where solids are separated from the mother liquor and washed. Moist cake is dried in a fluidised bed dryer and packed into big bags for shipment to market. Spodumene conversion has been tested at bench-scale on Länttä and Syväjärvi and Rapasaari concentrates and at pilot-scale on Länttä, Syväjärvi and Rapasaari concentrates. Conversion parameters are reasonably well understood but further pilot-scale tests would be required on the other main sources of concentrate to ensure adequate understanding of variability in performance. From 2015 to 2018, laboratory and pilot tests were undertaken on Länttä, Syväjärvi and Rapasaari concentrates from the spodumene concentrate conversion to lithium carbonate production. Following the decision to produce lithium hydroxide rather than lithium carbonate, semi-continuous bench-scale tests were undertaken in 2019 to produce lithium hydroxide. This was followed by continuous pilot testing in 2020 using Syväjärvi beta-spodumene concentrate and in 2022 on Rapasaari beta-spodumene concentrate. The soda leach developed by Outotec is a novel process but one that has been successfully demonstrated at pilot-scale on Syväjärvi and Rapasaari beta-spodumene concentrates. Ideally, other concentrates should also be subjected to conversion and hydrometallurgical testing. 21.4 Mining and Mineral Reserves Open pit mining is considered appropriate for the orebody characteristics. The modifying factors applied in the Mineral Resource to Mineral Reserve conversion are appropriate for the ore body type taking in consideration the concentrating process. No Inferred Mineral Resources were included in the mine design. Measured and Indicated Mineral Resources has been converted to Proven and Probable Mineral Reserves. From the data received it has been shown that the open pit optimizations have been studied rigorously and accurately. The practical pit designs have been prepared based on the optimum pit shells defined in the optimization. Taking in consideration the geotechnical slope design parameters and equipment sizes for the haul roads. The waste dumps has sufficient space for waste material. 21.5 Adjacent properties Keliber is the most advanced lithium project in the region. The other exploration projects do not yet have estimated Mineral Resources declared; however, they share similar characteristics and mineralisation style to the orebodies declared by Keliber. It is likely that there is potential for identification and exploration of additional similar orebodies in the region. 21.6 Risk review and opportunities The review identified that the key risks for Keliber are in line with those expected during early project-related phases; i.e., uncertainty regarding permitting, water-related concerns and issues related to the estimation of the Mineral Resources. The inclusion of the battery metals assets into SSW’s portfolio and battery metals strategy is a strategic step to acquire further downstream exposure to the battery metals value chain. Lithium hydroxide (a chemical needed in the production of the cathode active material in modern high-nickel cathode materials, which provide higher energy density) is predicted by some to become the dominant lithium chemical consumed in battery applications. Keliber intends to offer lithium hydroxide to the strongly growing lithium battery market. The battery-grade lithium hydroxide produced can be used for the manufacturing of batteries for increasingly electrifying transport (electric and hybrid vehicles) as well as in the production of batteries for energy storage. SRK Consulting – 592138 SSW Keliber TRS Page 226 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date:13 December 2023 Effective Date: 31 December 2022 21.7 Economic Analysis The Net Present Value (NPV) of the post-tax cash flows for Keliber Mine and Concentrator is shown for a range of discount rates in Table 21-1. The NPV is determined in the model in euros and converted to ZAR and USD at the prevailing spot rate from 30 December 2022, the closest date to the Effective Date for which data is available. Table 21-1: Sensitivity to Discount Rate Discount Rate NPV (EURm) (USDm) (ZARm) 6.0% 223 239 4 058 8.0% 176 188 3 198 10.0% 136.4 145.8 2 478 12.0% 103 110 1 872 14.0% 75 80 1 358 The default price assumptions used are from the UBS December 2022 price deck. The average of the surveyed analysts is used in the Economic Analysis. A two-factor sensitivity, showing the sensitivity of the NPV to the USD price for spodumene concentrate and the working costs is included in Table 21-2. Table 21-2: Sensitivity of NPV to Changes in Price and Working Costs NPV in EURm Long-term concentrate price (USD/t) 834 886 938 990 1 042 1 094 1 146 1 198 1 250 84.7 -20% -15% -10% -5% 0% 5% 10% 15% 20% Working Costs (EUR/t) 61.7 - 10% 39 69 100 130 160 190 221 251 281 65.1 -5% 27 58 88 118 148 179 209 239 269 68.5 0% 15 46 76 106 136.4 167 197 227 257 71.9 5% 3 34 64 94 124.5 155 185 215 245 75.4 10% - 8 22 52 82 113 142.8 173 203 234 The average working costs are EUR68.5/t and the forecast long-term spodumene price is USD1042/t. The price and the associated forecast is currently very volatile. However, the operating margin of the mine and concentrator is currently estimated at 42% for the scheduled life of mine (LoM). The company has funded the capital for the project and limited liquidity risk is present. The operating margin is generally healthy and although the NPV changes substantially in response to price changes the operating margin is forecast to remain positive under most foreseeable scenarios. The post-tax NPV of the Mine and Concentrator producing spodumene concentrate for sale to a third-party is estimated at EUR136.4 million at a 10% real discount rate with an IRR of 21.5%. This is on a 100% attributable basis. Sibanye-Stillwater owns 84.96%. The integration of the Refinery significantly improves the economics. However, the Refinery is not considered a Mineral Asset. A more detailed explanation is included in the Economic Analysis chapter along with the cash flows of the integrated business. The company intends to operate the business as an integrated business for the period where both the mine and the Refinery are operating. However, the Refinery will operate independently before and after the mine life and has the potential to expand to process third-party concentrates or produce alternate products during the mine life. SRK Consulting – 592138 SSW Keliber TRS Page 227 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date:13 December 2023 Effective Date: 31 December 2022 22 RECOMMENDATIONS [§229.601(b)(96)(iii)(B)(23) 22.1 Exploration SRK recommends that Keliber utilises an umpire/check laboratory to analyse a sub set of the previously analysed samples (~100 samples), representative of the grade range of the deposits, and to include additional commercially available CRM’s as part of its QC programme going forward in order to address the possible negative bias observed after 2021. The cost of the Umpire laboratory checks is expected to be approximately EUR10k. The cost of commercially available Li CRMs for a three year time period would be approximately EUR3k. 22.2 Hydrogeological investigation Further site-specific hydrogeological characterisation and assessment is required for the Outovesi and Länttä deposits to meet licencing and feasibility requirements. The surface water-groundwater interaction should be further understood, and the water balance further refined to include actual flows instead of modelled flows for some areas. The water quality baseline should be further refined using appropriate measurement and analysis methodologies, and further baseline data should be collected as the project progresses. The estimated cost for this are between USD250k and USD450k 22.3 Geotechnical testing The level of understanding of rock strength parameters needs to be appraised focusing on both intact and discontinuity strength (shear strength) using further laboratory test work and regular updates of the geotechnical database should be done, with continuous mine design validation. Further test work should be carried out during the mine design phase to appraise the available data. Additional test types that should be carried out include: • Triaxial strength test (at appropriate confining stresses for the mining environment); • Base friction angle tests; • Joint shear tests; and • Oriented geotechnical boreholes are required for detailed rock mass quality and rock strength assessment, particularly to assess the impact of geological structures and rock mass fabric. In Syväjärvi and Rapasaari, the specific geotechnical drilling will be conducted to get more information about rock mechanical and geotechnical features of different rock types and structural zones, especially in the ramp and other critical areas of the planned open pit areas. The estimated costs of a 1 200m geotechnical drilling program are between EUR15k and EUR200k. 22.4 Mineral Resources SRK considers there to be potential for definition of additional Mineral Resources through the planned exploration programme and through targeted extension of the already-defined orebodies. Infill drilling in the smaller vein systems will improve the confidence in the size and grade of these orebodies. The exploration program costing is detailed in section 20.2. 22.5 Metallurgical testing and mineral processing 22.5.1 Ore beneficiation Given the possibility that ore sorting of mined ore may be less efficient than that of the artificial composite ore feed, it is recommended that samples of mined ore from all deposits be subjected to pilot ore sorting tests using the preferred sensor technology. Flotation parameters are reasonably well understood but it is recommended that pilot-scale tests be undertaken on ores that were only tested at bench-scale. Variability flotation tests were undertaken on Rapasaari samples selected from four different mineralised material types. It is recommended that similar variability programs be undertaken on all other deposits to ensure adequate understanding of spatial variability in flotation performance. 22.5.2 Chemical processing Following the decision to produce lithium hydroxide rather than lithium carbonate, semi-continuous bench-scale tests were undertaken in 2019 to produce lithium hydroxide. This was followed by continuous pilot testing in 2020 using Syväjärvi beta-spodumene concentrate and in 2022 using Rapasaari beta-spodumene concentrate. Ideally,
SRK Consulting – 592138 SSW Keliber TRS Page 228 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date:13 December 2023 Effective Date: 31 December 2022 other concentrates should also be subjected to conversion and hydrometallurgical testing. However, given reported chemical and mineralogical similarities between the ore sources, it is likely that their concentrates will perform similarly to Syväjärvi and Rapasaari. Notwithstanding this, SRK recommends that the mineralogical and chemical similarity of other concentrates be assessed and that they be subjected to conversion and hydrometallurgical testing if significantly different to Syväjärvi or Rapasaari. Keliber has been actively doing test work since 2000. Based on the historic cost the estimated cost per bulk sample are the following: • Sourcing of material with pilot test tunnel between EUR250k and EUR350k depending on sample depth; • XRT sorting between EUR150k and EUR200k; • Milling and flotation pilot testwork between EUR1,2m and EUR1.5m; and • Conversion and Lithium Hydroxide refining testwork between EUR1.0m and EUR1.5m It is estimated as a minimum that another 2 pilot test runs will need to be done per mining property, thus at least eight bulk samples (160kg each) for the four open pit properties. 22.6 Mineral Reserve Keliber is considering underground mining in three orebodies; two are underground extensions that are planned to follow open pit operations in Rapasaari and Länttä; the third is a solely underground mine in Emmes. Engineering study work has been done for the proposed underground mines that SRK considers to be to a scoping study level of accuracy. The three orebodies are similar in nature, steeply dipping and fairly narrow and appear to have similar geotechnical characteristics. A bench and fill mining method has been selected to be the base-case method, mined from the bottom of each orebody upwards in 20-m lifts, with fill being uncemented open pit waste rock and waste development. Based on the information reviewed, SRK considers the mining method to be appropriate. Rapasaari and Länttä are proposed to be accessed via declines from the respective pits and, because the Emmes orebody is beneath a lake, the decline planned to access Emmes is developed from dry land on Åmudsbacken, a nearby property. It is recommended to include more detailed studies in respect of: • Hydrogeological; o Estimated study cost between EUR150k and EUR 250k. • Geotechnical; o Estimated study cost between EUR 150k and EUR 250k. • Backfill; o Estimated study cost between EUR 100k and EUR 175k. • Ventilation; o Estimated study cost between EUR 100k and EUR 175k • Underground electrics before declaration of Mineral Reserves for the underground operations. o Estimated study cost between EUR 150k and EUR 250k Additional to the above will be drilling for the Hydrogeological and Geotechnical study for which the cost estimate can be anything between EUR 1.0m and EUR 2m. Further cost for test work on material for the backfilling can be estimated between EUR 200k and EUR 300k. SRK Consulting – 592138 SSW Keliber TRS Page 229 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date:13 December 2023 Effective Date: 31 December 2022 23 REFERENCES/DATA SOURCES [§229.601(b)(96)(iii)(B)(24)] 23.1 Documents provided by the Company Afry Finland Oy. (2021). Keliber Lithium Project – Definitive Feasibility Study Site Water Management Plan. Project ID: 101016050-003. Alviola, R., Mänttari, I., Mäkitie, H. and Vaasjoki, M. (2001). Svecofennian rare-element granitic pegmatites of the Ostrobothnian region, Western Finland; their metamorphic environment and time of intrusion. Special paper 30:9- 29," Geological Survey of Finland, GTK, 2001. Ahtola, T. (ed.), Kuusela, J., Käpyaho, A. & Kontoniemi, O. (2015). Overview of lithium pegmatite exploration in the Kaustinen area in 2003–2012. Geological Survey of Finland, Report of Investigation 20, 28 pages, 14 figures and 7 tables. Bradley, D., and McCauley, A. (2016). A Preliminary Deposit Model for Lithium-Cesium-Tantalum. Černý, P. and Ercit, T. S., (2005). The Classification of Granitic Pegmatites Revisited. The Canadian Mineralogist 43: 2005–26. Fastmarkets. (2022). Lithium Market Study (Independent verification Study). March 2022. Hatch (2019). Keliber Lithium Project Definitive Feasibility Study Report. p.64. Hills, V. (2022). Email from Vic Hills to Andrew van Zyl and others, dated 07 February 2022. Keliber (2022) Keliber_Economic_Model_v2.5.1_LoMvDFS21_SSW adjustments (ID 36372) RSa 18122022.xlsx Keliber (2023a), Email from Lassi Lammassaari entitled SRK SA:n tietopyyntö, 3 March 2023 London, D. (2016). Rare-Element Granitic Pegmatites. In. Reviews in Economic Geology v.18. pp 165-193. Society of Economic Geologists 2016 Pöyry Finland Oy. (2017).Preliminary Slope Design Study of Syväjärvi, Rapasaari, Länttä and Outovesi deposits. Pöyry Finland Oy. (2018). Rock mechanical investigation of the Syväjärvi and Rapasaari Li-deposits. 13 November 2018. Project number 101009983-001. Confidential. 35pp. Pöyry Finland Oy, (2019). Rock mechanical investigation of the Emmes and Outovesi Li deposits. Pöyry Finland Oy. (2019a). Rock mechanical investigation of the Länttä Li-deposit. SRK Consulting (Finland) Oy ("SRK Finland"). (2015). Syväjärvi Pit, Geotechnical Slope Design. September 2015. Project number FI626. 24pp. Vaasjoki, M., Korsman, K. & Koistinen, T. (2005). Overview. In: Precambrian geology of Finland: key to the evolution of the Fennoscandian Shield. Developments in Precambrian geology 14. Amsterdam: Elsevier, 1–17. Wood Mackenzie. (2021). 2021 Lithium Market Study for Kaustinen/Kokkola DFS. 20 December 2021. WSP Global Inc. (WSP) (2022). Keliber Lithium Project Definitive Feasibility Study Report. WSP Global Inc. (2022a). Keliber Lithium Project. Definitive Feasibility Study Report. Volume 1: Executive Summary. Final. 1st February 2022. Confidential. 62pp. WSP Global Inc. (2022b). Keliber Lithium Project. Definitive Feasibility Study Report. Volume 2: Chapters 2-12. Draft. 11th January 2022. Confidential. 108pp. WSP Global Inc. (2022c). Keliber Lithium Project. Definitive Feasibility Study Report. Volume 3: Chapters 13-17. Draft. 18th January 2022. Draft. Confidential. 411pp. WSP Global Inc. (2022d). Keliber Lithium Project. Definitive Feasibility Study Report. Volume 4: Chapters 18-19. Draft. January 2022. Confidential. 255pp. WSP Global Inc. (2022e). Keliber Lithium Project. Definitive Feasibility Study Report. Volume 5: Chapter 20. Draft. January 2022. Confidential. 114pp. WSP Global Inc. (2022f). Keliber Lithium Project. Definitive Feasibility Study Report. Volume 6: Chapters 21-26. Draft. 27th January 2022. Confidential. 91pp. SRK Consulting – 592138 SSW Keliber TRS Page 230 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date:13 December 2023 Effective Date: 31 December 2022 WSP Global Inc. (2022g). Keliber Lithium Project. Definitive Feasibility Study Report. Volume 7: Appendices List. Draft. 11th February 2022. Confidential. 1pp. 23.2 Public domain documents Central Ostrobothnia Finland Climate. https://tcktcktck.org/finland/central-ostrobothnia#t1. Accessed 17 February 2022. Cision (2021). FLSmidth to Provide Process Engineering Services at Keliber’s Concentrator Plant. Accessed https://news.cision.com/keliber/r/flsmidth-to-provide-process-engineering-services-at-keliber-s-concentrator- plant,c3366399, date of access 19 February 2022. Climate and Average Weather Year Round in Kokkola. https://weatherspark.com/y/90442/Average-Weather-in- Kokkola-Finland-Year-Round. Accessed 17 February 2022. Innovation News Network (“INS”) (2021). Building batteries: Why lithium and why lithium hydroxide? https://www.innovationnewsnetwork.com/lithium-hydroxide/9218/. Accessed 31/02/2023. Keliber Oy. (2020). Presentation: Keliber Lithium Project – the most advanced in Europe. 26 May 2020. Hannu Hautala, CEO. 16pp. Keliber Oy. (2022a). Announcement for the Environmental Impact Assessment for the Kokkola Lithium Chemical Plant. Accessed https://www.keliber.fi/en/news/reports-and-publications/eia/, date of access 19 February 2022. McKinsey & Company (2022). Lithium Mining: How new production technologies could fuel the global EV revolution. https://www.mckinsey.com/industries/metals-and-mining/our-insights/lithium-mining-how-new- production-technologies-could-fuel-the-global-ev-revolution. Accessed 31/02/2023. Mining Weekly article. https://www.miningweekly.com/article/keliber-receives-mining-permit-for-rapasaari- deposit-2022-03-24/rep_id:3650. Accessed 24 March 2022. Organisation for Economic Co-operation and Development (OECD) iLibrary, July 2019, Critical resilience case- study: Electricity transmission and distribution in Finland, https://www.oecd-ilibrary.org/sites/93ebe91e- en/index.html?itemId=/content/component/93ebe91e-en. Accessed 26 January 2022. SRK Consulting – 592138 SSW Keliber TRS Page 231 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date:13 December 2023 Effective Date: 31 December 2022 24 RELIANCE ON INFORMATION PROVIDED BY REGISTRANT [§229.601(b)(96)(iii)(B)(25)] SRK has relied on information provided by SSW (the registrant) and its advisors in preparing this TRS the following aspects of the modifying factors which are outside of SRK’s expertise: • Economic trends, data, assumptions and commodity price forecasts (Sections 15); • Marketing information (Section 15); • Legal matters, tenure and permitting/authorization status (Section 2.3). • Agreements with local communities (Section 16). SRK believes it is reasonable to rely upon the registrant for the above information, for the following reasons: • Commodity prices and exchange rates – SRK does not have in-house expertise in forecasting commodity prices and exchange rates and would defer to industry experts, such as CRU, for such information which came via the Company; • SRK has reviewed the publicly available data to confirm the data provided by the registrant and is satisfied there is acceptable agreement; and • Legal matters – SRK does not have in-house expertise to confirm that all mineral rights and environmental authorisations/permits have been legally granted and correctly registered. SRK would defer to a written legal opinion on the validity of such rights and authorisations, which would be provided by the Company. SSW has confirmed in writing that to its knowledge, the information provided by it to SRK was complete and not incorrect, misleading or irrelevant in any material aspect. SRK has no reason to believe that any material facts have been withheld.
SRK Consulting – 592138 SSW Keliber TRS Page 232 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date:13 December 2023 Effective Date: 31 December 2022 25 DATE AND SIGNATURE PAGE This TRS documents and justifies the Mineral Resource and Mineral Reserve statements for SSW’s Keliber assets located in Central Ostrobothnia, Finland as prepared by SRK in accordance with the requirements of S- K1300 and the SAMREC Code. The opinions expressed in this TRS are correct at the Effective Date of 31 December 2022. We, SRK Consulting (South Africa) (Pty) Ltd, are the Qualified Persons (as defined in S-K1300) who are responsible for authoring this Technical Report Summary in relation to the Keliber Lithium Project. We hereby consent to the following: • the public filing and use by Sibanye Stillwater Limited (“Sibanye-Stillwater”) of the Keliber Lithium Project Technical Report Summary; • the use and reference of our name, including our status as experts or Qualified Persons (as defined in S- K1300) in connection with this Technical Report Summary for which we are responsible; • the use of any extracts from, information derived from or summary of this Technical Report Summary for which we are responsible in the annual report of Sibanye-Stillwater on Form 20-F for the year ended 31 December 2022 (“Form 20-F”); and • the incorporation by reference of the above items as included in the Form 20-F into Sibanye-Stillwater’s registration statement on Form F-3 (File No. 333-234096) (and any amendments or supplements thereto). This consent pertains to the Keliber Lithium Project Technical Report Summary, and we certify that we have read the 20-F and that it fairly and accurately represents the information in the Keliber Lithium Project Technical Report Summary. SRK Consulting (South Africa) (Pty) Ltd Authorized Signatory Date: 13 December 2023 (Report Date: 13 December 2023) (Effective Date: 31 December 2022) SRK Consulting – 592138 SSW Keliber TRS Page 233 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 GLOSSARY OF TERMS, ABBREVIATIONS, UNITS TERMS Term Description assay the chemical analysis of ore samples to determine their metal content. dip the angle of inclination from the horizontal of a geological feature. fault a break in the continuity of a body of rock, usually accompanied by movement on one side of the break or the other so that what were once parts of one continuous rock stratum or vein are now separated granite a coarse-grained intrusive igneous rock composed mostly of quartz, alkali feldspar, and plagioclase granitoid a generic term for a diverse category of coarse-grained igneous rocks that consist predominantly of quartz, plagioclase, and alkali feldspar Indicated Mineral Resource that part of a Mineral Resource for which quantity, grade or quality, densities, shape and physical characteristics are estimated with sufficient confidence to allow the application of Modifying Factors in sufficient detail to support mine planning and evaluation of the economic viability of the deposit. Geological evidence is derived from adequately detailed and reliable exploration, sampling and testing which is sufficient to assume geological and grade or quality continuity between points of observation. Inferred Mineral Resource that part of a Mineral Resource for which quantity and grade or quality are estimated on the basis of limited geological evidence and sampling. Geological evidence is sufficient to imply but not verify geological and grade or quality continuity. An Inferred Mineral Resource has a lower level of confidence than that applying to an Indicated Mineral Resource and must not be converted to a Mineral Reserve. Kriging an interpolation method that minimizes the estimation error in the determination of a mineral resource. mafic a silicate mineral or igneous rock rich in magnesium and iron Measured Mineral Resource that part of a Mineral Resource for which quantity, grade or quality, densities, shape and physical characteristics are estimated with confidence sufficient to allow the application of Modifying Factors to support detailed mine planning and final evaluation of the economic viability of the deposit. Geological evidence is derived from detailed and reliable exploration, sampling and testing which is sufficient to confirm geological and grade or quality continuity between points of observation. A Measured Mineral Resource has a higher level of confidence than that applying to either an Indicated Mineral Resource or an Inferred Mineral Resource. It may be converted to a Proven Mineral Reserve or a Probable Mineral Reserve. metasedimentary originally a sedimentary rock that has undergone a degree of metamorphism, but the physical characteristics of the original material have not been destroyed Mineral Reserve the economically mineable part of a Measured and/or Indicated Mineral Resource. It includes diluting materials and allowances for losses, which may occur when the material is mined or extracted and is defined by studies at Pre-Feasibility or Feasibility level as appropriate that include applications of Modifying Factors. Such studies demonstrate that, at the time of reporting, extraction could reasonably be justified. The reference point at which Mineral Reserves are defined, usually the point where the ore is delivered to the processing plant, must be stated. It is important that, in all situations where the reference point is different, such as for saleable product, a clarifying statement is included to ensure that the reader is fully informed as to what is being reported. Mineral Resource a concentration or occurrence of solid material of economic interest in or on the Earth’s crust in such a form, grade or qual ity, and quantity that there are reasonable prospects for eventual economic extraction. The location, quantity, grade, continuity and other geological characteristics of a Mineral Resource are known, estimated or interpreted from specific geological evidence and knowledge, including sampling. outcrop a visible exposure of bedrock or ancient superficial deposits on the surface of the Earth overburden material, usually barren rock overlying a useful mineral deposit. pegmatite a coarsely crystalline igneous rock with crystals several centimetres in length plagioclase feldspar a group of feldspar minerals that forms a solid solution series ranging from pure albite Na(AlSi3O8), to pure anorthite Ca(Al2Si2O8). Probable Mineral Reserve the economically mineable part of an Indicated, and in some circumstances, a Measured Mineral Resource. The confidence in the Modifying Factors applying to a Probable Mineral Reserve is lower than that applying to a Proven Mineral Reserve. Proven Mineral Reserve the economically mineable part of a Measured Mineral Resource. A Proven Mineral Reserve implies a high degree of confidence in the Modifying Factors. pyrite an iron sulfide mineral with the chemical formula FeS2 (iron (II) disulfide); pyrite is the most abundant sulfide mineral pyrrhotite an iron sulfide mineral with the formula Fe(1-x)S (x = 0 to 0.2) reef a thin, continuous layer of ore-bearing rock RoM Run-of-Mine – usually ore produced from the mine for delivery to the process plant. serpentine a name used for a large group of minerals that fit the generalized formula (Mg,Fe,Ni, Mn,Zn)2-3(Si,Al,Fe)2O5(OH)4 spodumene a pyroxene mineral consisting of lithium aluminium inosilicate, LiAl(SiO3)2 stratigraphic column a grouping of sequences of strata onto systems stripping ratio ratio of waste rock to ore in an open pit mining operation sulfide An inorganic anion of sulfur with the chemical formula S2−or a compound containing one or more S2− ions tailings refuse or dross remaining after the mineral has been removed from the ore - metallurgical plant waste product variogram a measure of the average variance between sample locations as a function of sample separation volcanics rocks formed from lava erupted from a volcano SRK Consulting – 592138 SSW Keliber TRS Page 234 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 ABBREVIATIONS Acronym Definition 2D two dimensional AAS Atomic Absorption Spectrometry AG autogenous grinding AMD Acid Mine Drainage AMIS African Mineral Standards APC Advanced Process Control AVI Regional State Administrative Agency BAP Biodiversity Action Plan BOQ Bills of Quantities BR indirect tensile strength tests (Brazilian) BWI Bond Ball Mill Work Indices Capex Capital expenditure CCTV Closed Circuit Television CoG cut-off grade CoP Code of Practise COO Chief Operating Officer CPI consumer price indices CRM certified reference material °C Degrees Celsius dB(A) Decibel DCS Distributed Control System DFS Definitive Feasibility Study DMS Dense Media Separation DPM diesel particulate matter DSO Distribution System Operator E Young’s modulus EBIT earnings before interest and taxes EIA Environmental Impact Assessment EMI Environmental Management Inspectors EMP Environmental Management Programme EMPr Environmental Management Programme Report EPCM Engineering, Procurement and Construction Management EQS environmental quality standard Eurofin Eurofin Labtium Group EU European Union FAR fresh air raise FoG Fall of Ground FS Feasibility Study G&A general and administration GCMP Ground Control Management Plan GHG Green House Gas GISTM Global Industry Standard on Tailings Management GPS global positioning system GSI geological strength index GTK Geological Survey of Finland HARD Half Absolute Relative Difference HDPE high-density polyethylene HLS Heavy liquid separation HSE Health, Safety and Environment HR Human resources HRD Human Resources Development HVAC Heating, Ventilation and Air Conditioning ICE internal combustion engine ICP-MS Inductively Coupled Plasma - Mass Spectroscopy ICP-OES Inductively Coupled Plasma - Optical Emission Spectroscopy ID2 Inverse Distance Squared IE International Efficiency ISRM International Society for Rock Mechanics IT Intermediate Volcanics KEO Kokkolan Energiaverkot Oy SRK Consulting – 592138 SSW Keliber TRS Page 235 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Acronym Definition KL Mica Schist KSL Sulfidic Mica Schist LCT Lithium-Caesium-Tantalum LED local economic development LHD load-haul-dump LHOS long hole open stoping LiOH Lithium Hydroxide LoM Life-of-mine LPG Liquid Petroleum Gas LT long term LV low voltage M&I Measured and Indicated (Measured and Indicated Mineral Resources) MF2 mill-float-mill-float MLA Mineral Liberation Analyser MRA Mining Right Application MRMR Laubscher’s Mining Rock Mass System MVR mechanical vapour recompression MWP Mine Works Programme N’ Stability Number NCCRP National Climate Change Response Policy NDC National Determined Contribution NDP National Development Plan NIHL Noise Induced Hearing Loss NIR Near Infra-Red NPAT net profit after tax NPV Net Present Value OAD Obstructive Airway Disease OECD Organisation for Economic Co-operation and Development OEL occupational exposure limits OK Ordinary Kriging OP open pit Opex Operating expenditure PCD Pollution Control Dam PFS Prefeasibility Study PoC proof of concept PP Plagioclase porphyrite ppm parts per million PSA pool-and-share arrangement Q Barton’s Q Rock Mass Rating System Q’ rock quality rating number QA/QC Quality Assurance / Quality Control QC Quality Control QP Qualified Person QS Quantity Surveyor R&D research and development RAR return air raises RAW return airway RBH raise bore holes RoM Run of Mine RIO Remote Input Output RPEE Reasonable Prospects of Eventual Economic Extraction RQD Rock Quality Designation RWD return water dam RWI Bond Rod Mill Work Indices SCADA Supervisory Control and Data Acquisition SD Supplier Development SEC Securities and Exchange Commission Sedar System for Electronic Document Analysis and Retrieval SEP Stakeholder Engagement Plan SHEQ safety, health, environment and quality S-K1300 Subpart 1300 of Regulation S-K SLP Social and Labour Plan
SRK Consulting – 592138 SSW Keliber TRS Page 236 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 Acronym Definition SOP Standard Operating Procedures SPG Spodumene pegmatite. SRK SRK Consulting (South Africa) (Pty) Ltd SSW Sibanye Stillwater Limited Sweco Sweco Oy SWMP Stormwater Management Plan TB Tuberculosis TCR Total Core Recovery TEM Technical-economic model TEP Technical-economic parameter TMM trackless mobile machinery TRS Technical Report Summary TSF tailings storage facility TSP tailings scavenging circuit TUKES Finnish Safety and Chemicals Agency UCS Uniaxial Compressive Strength UG Underground UPS Uninterruptable Power Supply UV utility vehicle v Poisson’s ratio VKO Verkko Korpela Oy VSD variable speed drives WACC weighted average cost of capital WHIMS Wet High Intensity Magnetic Separation WHO World Health Organization WRSF Waste rock storage facility WSM World Stress Map XRD X-Ray Diffraction XRT X-Ray Transmission CHEMICAL ELEMENTS and COMPUNDS Symbol Element Al aluminium As arsenic Be beryllium Ca calcium Cd cadmium Co cobalt Cs caesium Fe iron HCl hydrogen chloride HNO3 nitric acid Li lithium Li2O Lithium Oxide LiAl(SiO3)2 Lithium Aluminium Inosilicate (spodumene) Li2CO3 Lithium Carbonate LiOH.H2O (LiOH) Lithium Hydroxide Monohydrate (or more simply Lithium Hydroxide) Mg magnesium Mn manganese Nb niobium Ni nickel O oxygen P phosphorus S sulfur Si silica Ta tantalum Zn zinc SRK Consulting – 592138 SSW Keliber TRS Page 237 SRK SSW_Keliber Project TRS_Final 13 December 2023 Report date: 13 December 2023 Effective Date: 31 December 2022 UNITS Acronym Definition A ampere cm a centimetre EUR Euro, official currency of the European Union EURbn one billion Euros EURk one thousand Euros EURm one million Euros EUR/t Euro per tonne g grammes g/t grammes per metric tonne – metal concentration ha a hectare kg one thousand grammes Kg/h kilograms per hour km a kilometre kt a thousand metric tonnes ktpa a thousand tonnes per annum ktpm a thousand tonnes per month kV one thousand volts kVA one thousand volt-amperes kW kilowatt kWh kilo watt hours l a litre m a metre m3 cubic metre m3/s cubic metres per second mg/m3 milligrams per cubic metre min minute mm millimetre m/s metres per second Ma a million years before present MPa a million pascals Mt a million metric tonnes Mtpa a million tonnes per annum MVA a million volt-amperes MW a million watts oz ounce t a metric tonne t/m3 / tm3 density measured as metric tonnes per cubic metre tpa tonnes per annum USD United States dollar USDbn One billion USD V volt wt% weight percent ZAR South African Rand ZARbn one billion ZAR ° degrees °C Degrees Celsius ‘ minutes % percentage