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Permit M-1977-493—Climax Mine Technical Revision 37 (TR-37) directly hauled from areas affected by mining activities to the reclamation site or placed in designated storage areas adjacent to each production area for easy reapplication to the disturbed area, as shown in Figure F-02. Reclamation cover has been salvaged and stockpiled at Climax since 1978. Current stockpiles located around the mine site include approximately 816,100 cubic yards for stockpiles west of State Highway 91 and 1,375,000 cubic yards east of the highway for future reclamation use (Figure F-02, Exhibit F). Additional soil will be salvaged from areas of planned disturbance prior to raising the dams on the Mayflower TSF and increasing the size of the McNulty OSF (Section 1-6 in Exhibit 1). Approximately 1,405,000 cubic yards, 1,965,000 cubic yards, and 126,000 cubic yards are planned to be salvaged from the McNulty OSF, Mayflower TSF, and pit areas, respectively. If necessary, BMPs will be implemented to reduce erosion from the new stockpiles. Climax is proposing two reclamation cover removal options. The first option is used when reclamation cover materials are being directly hauled from the disturbance area to reclamation. The second option is used when reclamation cover materials are being stockpiled for later redistribution. Exhibit 1: Soil Information contains the baseline soil salvage depth and volume tables for the McNulty and North 40 OSFs (Table 1-1) and Mayflower TSF (Table 1-2) mining areas. The baseline soil volume summary contained in Table 1-4 (Exhibit 1), contains a listing of soil removal areas and total salvage volumes compared to reclamation cover replacement volumes. The salvage depths are based on a critical review of the USFS White River and Pike soil survey soil map unit descriptions. Soil salvage depths will be determined by in-place soil monitoring to be conducted ahead of soil removal operations. Deep soils for reclamation cover are usually located in draws and valley floors while ridge tops have generally very shallow topsoil with high coarse fragment contents. Shallow ridge soils usually covers rocky parent material that may not be favorable for final reclamation and difficult to remove mechanically due to steep slopes and the high coarse fragment content. E-6.1.1 Direct Haul Reclamation Cover Salvage Climax recognizes the advantage to reclamation provided by directly hauling salvaged reclamation cover materials to final graded backfill whenever possible. Direct haulage of reclamation cover will improve the transfer of nutrients, organic matter, microbial populations, and residual native seed bank. When direct haulage of reclamation cover is performed outside of the active growing season, increased volunteer growth of plant propagules is supported. The following reclamation cover removal options will be considered when the salvaged soil is being directly hauled and placed on final graded backfill: 1) To reduce compaction and destruction of soil structure, consideration of soil moisture content will be utilized to optimize when soil moisture levels are sufficient to reduce dust yet dry enough to reduce soil mucking. 2) Stripping of reclamation cover from the bottom of drainages should be given priority to prevent contamination of soil by disturbed runoff. E-6.1.2 Stockpiled Reclamation Cover Salvage Option Whenever possible, soil stockpiles will be located to reduce haul distances and avoid handling materials multiple times. Soils removed from OSF locations will primarily be used to reclaim OSFs and the mill area, but excess materials may be hauled for reclamation on TSFs. Soils removed prior to expansion of the Mayflower TSF may be direct hauled for placement on the Tenmile TSF and/or stockpiled for future reclamation of the Mayflower TSF. Reclamation cover for stockpiling will be handled similarly to directly hauled material and reclamation cover will be removed, hauled, and placed on appropriately located and designated stockpiles in areas shown in Figure F-02 (Exhibit F) or other suitable locations that may be designated in the future. E-6.1.3 Stockpile Cover and Erosion Control Plan Reclamation cover will be stockpiled in such a manner to reduce wind and water erosion and unnecessary compaction.The primary methods of erosion control for soil stockpiles are timely revegetation and/or the use of temporary erosion control measures such as surface roughening, surface mulches, berms, ditches, or small sediment traps. Reclamation cover stockpiles will generally be constructed with 2.OH:1 V or flatter slopes. Stockpiled reclamation cover will be seeded with the temporary revegetation seed mixture (Section E-7.1.1). The estimated quantity of soil that will be generated during future mining activities is discussed in Exhibit 1: Soil Resources. Exhibit E E-4 March 2024