2023-10-30_PERMIT FILE - M2023015 (2)

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LONDON MINE M-2023-015 Updated Exhibit D—Rule 6.3.4 Reclamation Plan The post-mining land use of this site is Commercial/Industrial. Past disturbances included historic mining and processing, recent water quality activities, and finally the moving and sorting of old mine waste. There was no previously-unaffected area within this permit; no native ground with soil to salvage, no vegetation to re-establish. The reclamation of this site concentrates on stabilizing these lands to minimize surface runoff and ground percolation of mineralized water,offsite silt transport, and erosion. The onsite roads which pre-existed here were maintained during the mining stage and will remain as permanent features. The permanent onsite buildings were maintained and will remain onsite. All fuels,fluids,storage tanks and any contaminants will be removed from the site and disposed of in proper, licensed facilities as needed. All temporary structures will be removed from the site. Wooden waste materials will be legally burned or removed to a licensed landfill site as necessary. Any inert solid waste materials,such as concrete or stone will be broken as needed and buried onsite. Stockpiles of mineralized material will be removed; less-or non-mineralized materials will be placed in permanent disposal cells in stable configurations and locations. These areas are shown on the Reclamation Map in Exhibit E. The owner has requested that the Sorting Plant building remain on-site after completion of these permitted activities as it is a general purpose building. Runoff and sediment control structures,whether pre-existing or constructed for this operation,will most likely remain permanently on the site,due to the overall degree of disturbance,the surface slopes, and the proximity to Mosquito Creek. This is shown on the map in Exhibit E. Backfill will be placed and smoothed in stable lifts with the slope comprised of inert sorted product material, placed by loader or compacted dozer lifts. The surface will be sloped at 2H:1V as shown in Exhibit E Reclamation Plan. As native material is exposed,fine grained soil-like material will be excavated and stockpiled on the upgradient side of the area. Once material is excavated and stockpiled,soil tests will be conducted based on a 5-sample composited sample by a third-party laboratory to determine soil quality and what amendments if any are needed. If native soil horizon beneath the South London Stockpile area is impaired, it will be due to depletion of organic matter content and nutrients from being covered for many decades.Applicant will provide Division with the soil testing results and with Applicant's recommendations for amendment of the cover material,and demonstrate to the Division if the proposed cover stockpiled material is compliant with the Industrial Soil requirements provided by the Division. Upon such demonstration, and approval by the Division,Applicant will amend the fine-grained material with necessary compost and fertilizers as approved,and as needed to provide support for revegetation of the final cover.