2022-05-04_REVISION - C1981018 (9)

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The volumes of topsoil stripped from affected areas and reclaimed thickness are presented in Table V-4. Table V-4A gives the existing topsoil/subsoil stockpile estimate pertaining to the refuse areas. The areas of topsoil to be disturbed vs. soil mapping unit (soil type) and location of disturbance is presented in Table V-5. Topsoil material was not segregated in stockpiles by type, as soil tests and survey information indicated no advantages to segregation. Topsoil will be redistributed as promptly as practical. Grading work will be programmed to have finished slopes available on which to place topsoil as it is being stripped, where possible. This planning minimizes disturbed areas and topsoil handling. Permanent stockpiles of topsoil, for use during final reclamation, are placed on stable surfaces within the permit area where they will not be subject to additional disturbance, wind erosion, or compaction during mine life. Ditches are constructed above all topsoil stockpiles which are not located adjacent to a ridgeline, to prevent runoff from adjacent areas from entering the stockpile areas. Side slopes of topsoil stockpiles are not greater than 3h:1v. Side slopes of non-toxic fill (subsoil) stockpiles are not greater than 2h:1v. Side slopes of 3h:1v or steeper on stockpiles are heavily mulched. The stockpile locations are presented on Maps 26, 27, and 28 ("D" Portal), Map 82 (Refuse Disposal Area), Maps 70-75 (Refuse Haul Road), Maps 53 & 54 (Water Tank Area and Access Road), and Map 90 (Alluvial Well Area), Map 162 (Refuse Area A Site Plan), and Map 166 (RP-2/3/4/5 Soil Stockpiile Inventory). Topsoil stockpiles are seeded during the first available favorable planting period after removal. The stockpiles will not be disturbed prior to topsoil redistribution or additions without prior approval by DMG. The topsoil will be redistributed in a manner which achieves an approximate uniform thickness as required for the postmining land use. On gradual slopes, topsoil will be spread with scrapers, motor graders, and dozers. On steep slopes, the topsoil will be spread with tracked dozers. Excess compaction of the topsoil will be avoided. On slopes of 3h:1v or steeper, the topsoils will be spread and furrowed on the contour or tracked by a dozer to retard erosion and help retain runoff. Topsoil will be protected to prevent excess wind and water erosion before revegetation operations. Other specific erosion control practices are discussed in Section V.I., Revegetation. Nutrients and soil amendments will be added as required to the redistributed topsoil so that it can support the proposed postmining activities. The types and amounts of materials added will be based on soils tests performed by a qualified soils laboratory and the vegetative responses desired. All treatments will be subject to review by the DMG. Table V-6 shows areas reclaimed during construction, areas to be reclaimed at the time of mine closure and areas that will not be reclaimed because of continued use. TR-74 (04/2022) V-25