2025-06-23_REVISION - M1980244 (23)

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Docusign Envelope ID:45B9721 C-FDE2-4821-B686-80BBC79CA6DD 37. Within Section 3, the report summarizes geotechnical investigations which include AM13 VLF2 Phase 3 expansion boreholes (2020) paired with AM14 VLF1 Phase 6 and VLF2 • Phase 4 test pits (2023)and geophysical surveys(2023). Please discuss how the results from the AM14 test pits and geophysical surveys correlate to the data from the AM13 boreholes and why a borehole investigation is not warranted for the AM14 areas. The AM14 area is characterized by near surface bedrock, confirmed through test pits and geophysical surveys in the VLF2 Stage 4 expansion area. These investigations correlate well with the data from the AM13 boreholes, where drilling was necessary to determine bedrock depth due to uncertain subsurface conditions created by mass fill grading in the area. In AM13, boreholes were required because: • BH01 was located adjacent to a haul road with no visible road cuts to infer bedrock depth. • BH02 was in a laydown yard adjacent to a building on a pad that had been re-graded. • BH03, BH04, BH05, and BH06 were located on stockpiled material, preventing reliable depth to bedrock estimates. In contrast, AM14 features exposed bedrock on the existing ground slopes and in road cut sections prevalent across the entire expansion area footprint. The geophysical survey results provided initial bedrock depth estimates, which were confirmed by the test pits. Additionally, large, disturbed bulk samples of foundation material were collected to develop material strength parameters. Given these comprehensive investigations, further borehole drilling is unnecessary in AM14. 38. Section 4.1 discusses that except for Joe Dandy Hill,the VLF1 and VLF2 expansions' footprint predominately sits within previously disturbed land and how the underground workings have been removed or already remediated. Please provide all known data on the location and how these features have been addressed.A review of historical imagery and records may be needed to determine the location of surface features in the area. Please • also provide a plan for how these features will be investigated during the construction of the VLF expansions to ensure compliance with the technical specifications and design of the facility. The underground workings within the existing Mill Platform footprint were remediated and documented in the "Cripple Creek& Victor Gold Mining Company Mill Site Earthworks Project Final Report Quality Assurance Monitoring & Test Results"dated January 31, 2014. The voids department digitized underground workings and current data-set indicate there are no underground workings in the area of the AM-14 leach pad expansions. 39. At the end of Section 4.1 is a comment noting that any mine placed pit backfill material prior to the construction of the VLF composite liner system is outside of the scope of the project nor a feature of the EPF.This is a similar comment the Division was concerned about regarding the Schist Island backfill in AM13 permitting. Please provide appropriate details of how mine placed pit backfill will be handled. Please refer to Adequacy Review Item 73 throughout the review of AM13. CC&V will implement operator training to aid in recognition of oversized material (greater than 5) and to manage larger material within spec (-5' boulders) to reduce the potential of loading multiple -5" rocks within the same truck and placing these large particles adjacent to each other. Additionally, to ensure backfill material is within the specification, CC&V will conduct monthly photographic analyses of loaded material to be used during the bulk backfill operations. The EoR will designate a CC&V employee (s) to observe, record, and photograph bulk backfill placement under the EoR's direction. The designee will record photographs of dumping operations and complete an inspection template developed by the EoR on a weekly basis. The EoR will perform • spot checks on site and review placement records with the CC&V designee on a quarterly basis. SSR Mining Inc. PAGE 10/19