2016-05-03_PERMIT FILE - C1981008A (19)

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16. Topsoil Stripping Procedures Prior to February 2008, the 1998/1999 expansion area was stripped in one mixed lift which was the A and B lifts combined. The current topsoil balance is shown on Map 2.05.4-9. All topsoil replacement thicknesses are shown on the Map for the entire permit area. Topsoil was salvaged from all significant disturbance areas including sediment ponds (includes pond area, embankment, and spillway), mining activities, spoil stockpiles, haul roads, access roads, mining area (includes box cut spoil and highwall reduction area) shop area, and diversion ditches. Topsoil was removed from all cut and fill slopes. No topsoil was salvaged from the light use roads utilized for environmental monitoring or power line corridors, except where cut and fills are required. Prior to topsoil removal, vegetation which is too large for incorporation into the topsoil was scraped away and combined with the overburden. The remaining vegetation was incorporated into the topsoil to help increase soil organic matter levels. To prevent unnecessary contamination, adequate extent of topsoil was salvaged from the edge of a road, embankment, ditch, cut slope, and toe of fill. For the original permit area, a two -lift topsoil operation was utilized for the two primary pre - mine irrigated pastureland soil types (30C and D70B), whereby the "A" and upper "B" horizons (Lift A) are salvaged separately from the lower "B" and "C" soil horizons (Lift B) (1988 - 1996 disturbance area). Specific Soil Map Units (1E, 1EW, and 808) at New Horizon 2 (1988 - 1996 disturbance area) was more suited for mixed one -lift topsoil salvage because they are very shallow to shallow, have little profile development, and/or are excessively stratified. The salvageable topsoil from these units was primarily utilized, whenever feasible, in postmine dry pastureland area. Table 2.04.9-6 reflects estimated salvage quantities for the 1996 study area and Tables 2.04.9-7A & B reflect estimated salvage quantities for the 1998 study area. As of PR 08, all topsoil stripping has been completed at the New Horizon Mine. The final topsoil replacement plans can be found in Section 2.05.4(2)(d). 16.1 Topsoil Salvase Thickness - 1988 Study Area This study addresses the approximate original permitted area of 274 acres or 235 disturbed acres, as shown on Map 2.04.9-1. The salvageable thickness of topsoil material presented in this section are based on laboratory data and extensive field observations, and represent only the most suitable sources of topsoil material. Table 2.04.9-5 summarizes topsoil salvage thickness and characteristics by map unit for the New Horizon 2 Mine disturbance area. It should be noted that the topsoil thickness and volumes listed in Table 2.04.9-5 are only estimates derived from field sample pits. WFC live handled the majority of the topsoil with trucks and the mine shovel January 2016 (TR -70) 2.04.9-17