2016-01-07_PERMIT FILE - C2010089A (16)

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lack salvageable topsoil either because the topsoil has already been removed or they contain coarse fragment contents which are too high for use as a plant growth medium. The area of these five topsoil mapping units which lack salvageable topsoil is 5.39 acres. The average stripping thickness for the combined horizons is depicted in the table found on Map 2.04.9-3 — Topsoil Salvage Map. The table on this map shows the average areas and volumes obtained from each soil mapping unit sampled. The volume of topsoil to be stockpiled is estimated at 220,000 bank cubic yards of which approximately 60,000 bank cubic yards will be the Progresso soils from the Garvey property which will be stored in a separate pile. See Map 2.05.4(2)(d)-2 for locations of the Progresso stockpiles and mixed topsoil piles. As shown on Map 2.04.9-3 — Topsoil Salvage Map, there are a total of six topsoil mapping units containing salvageable topsoil. These include topsoil mapping unit 81 PRO, containing 97.96 acres; topsoil mapping unit 77PIN, containing 79.98 acres; topsoil mapping unit REC, containing 74.67 acres; 82 PRO, containing 11.02 acres; soils mapping unit 78PIN, containing 8.06 acres; and topsoil mapping unit Aquolls, containing 3.76 acres. Topsoil Salvage Depths The available topsoil and salvageable depths for the permit area is shown on Map 2.04.9-3 — Topsoil Salvage Map. The overall topsoil balance for the mine was calculated by taking the weighted averages from each mapping unit shown on the map as well as the major inclusion areas. Generally, topsoil having a very high percentage of coarse fragments (greater than 20 percent by volume), very shallow bedrock (0 to 10 inches), and shallow ground water (less than 1 to 2 feet), have little suitable topsoil to be salvaged. No topsoil is available to be salvaged from existing roads, ponds, ditches, residences, or farmyards. Topsoil Stripping Before any area at the NHN Mine site other than a topsoil stockpile, light use access road, shallow drainage ditches, power line corridors and other small area exemption areas are disturbed, the suitable topsoil material will be removed. Suitable topsoil will be salvaged from all significant disturbance areas including sediment ponds (includes pond area, embankment, and spillway), mining activities, spoil stockpiles, haul roads, access roads, mining areas, facilities area, and diversion ditches, which extend below the depth of salvageable topsoil. Prior to topsoil removal, vegetation which is too large for incorporation into the topsoil will be scraped away, placed in the pit, or utilized on dryland pasture reclamation areas as habitat should the surface landowner agree with this practice. The remaining vegetation will be incorporated into the topsoil to help increase organic matter levels. To prevent unnecessary contamination, adequate Section 2.05.4(2)(d) Page 4 Sept. 2015 (TR -11)