2019-06-28_REVISION - M1977004 (11)

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Homestake Mining Company May 10,2019 Regular(112d)Operation Reclamation Permit Application Package discharged and will take actions necessary to assure all applicable groundwater standards are met. o Site preparation or construction in the "Mill Site" area will not be initiated until the MLRB approves a detailed site plan (however, note that the mill was never constructed). • Pitch Mine Reclamation Plan Amendment; Permit #77-4HR, January 16, 1984 (HMC, 1984). HMC submitted a revised Reclamation Plan as an amendment to the existing permit. The amendment stemmed from a request to review the current bonding level. HMC estimated a revised surety of $2.204MUSD (in 1983 dollars). In general, the reclamation plan consisted of the following: o The reclamation plan was intended to return the land to its pre-mining land use of wildlife, livestock grazing and recreation. The short-term plan was the reduction and prevention of erosion, while the long-term objective was the establishment of vegetation for wildlife and livestock in most areas, and the establishment of trees on benches within the South Pit. o The final slopes of dump faces will be regraded to approximately 2 horizontal to 1 vertical (2H:1 V)with the exception that the 10250 elevation on the North Dump will be regraded to a 3HAV slope. o Overall slopes in the open pit will remain at the mining slope angle, with wildlife access provided through a ramp at the north and the 10,380 elevation on the south side. o The design storm was selected to be the 200-year, 24-hour event, and hydraulic structures were designed to convey runoff from the design storm while functioning as a long-term maintenance-free facility. o A water reservoir and dam constructed in Indian Creek will remain to provide water resources for wildlife, protect flooding downstream and provide habitat for aquatic life. o A revegetation plan was presented for shrubs, trees and grasses, with grasslands on sloping areas, a mixture of grasses and shrubs on relatively flat areas and trees planned for benches on the South Pit above the permanent lake elevation. Topsoil segregation and stockpiling was not practical during construction, and the revegetation plan developed was without native topsoil. o The North Pit will be partially backfilled through the South Pit development. The East Wall and Tension crack will be graded to establish drainage and seeded to grass. o A pit lake was anticipated for the South Pit, with a spillway constructed at the 10380 elevation, and trees planted on the benches above the pit lake. o Low grade ore will be relocated to the 10450 stockpile in the North Dump, regraded to a slope of approximately 3H:1 V and covered with 0.5 to 1 ft of clay and two ft of overburden material. o The water treatment reservoir dam will remain in place, the existing decant structure sealed and abandoned, and the water treatment plant decommissioned and removed. EXHIBIT E-RULE 6.4.5(AMENDED RECLAMATION PLAN) Page 5 HOMESTAKE MINING COMPANY