1988-04-29_PERMIT FILE - C1981008A (54)

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• Topsoil shall be replaced along the contour, whenever feasible, to minimize potential erosion and topsoil/spoil interface slippage problems. This practice will be discontinued on steep slopes where the safety of the equipment operator is in jeopardy. Topsoil which is replaced on mined areas will be scarified on the contour to a depth of 12 to 24 inches with a chisel plow or multi-shank subsoiler. Prime farmland soils will be scarified as each 12 to 18 inch lift of topsoil is replaced. This operation, together with spoil scarification, will produce a favorable root growth medium. The operation of seedbed preparation will also reduce compaction, increase infiltration, and promote surface roughness. Spoil and topsoil scarification is also discussed in the Seedbed Preparation section of the Revegetation Plan (Tab 22). Whenever practical, the salvaged topsoil will be immediately transported to leveled backfill areas and placed on the regraded surface. The direct haul method is economically desirable and also maintains a high topsoil quality by a direct transfer of viable seeds, microbes, and roots; reduced compaction; better preserved structure; increased aeration; and stable nutrient status (Liberta, 1981; National Academy Press, 1981). • Topsoil will not be handled when saturated either during the initial stripping, respreading, or final grading. Handling sticky or plastic soils in a saturated state would reduce the quality of the topsoil by degrading the physical characteristics and tilth of the soil. A hard, compact surface layer would result, which would reduce or inhibit seed germination, seedling root establishment, and air and water penetration. Most of the topsoil material recommended for salvage has a sandy loam to clay loam soil texture which have low to moderate consistency limitations (Tab 9, Soil Survey). Specific protective measures will be utilized to minimize wind and water erosion. Such measures will include contour ripping or chisel plowing of regraded spoil and replaced topsoil and rapid establishment of vegetation. Long unbroken slopes will be avoided to minimize sediment runoff and gullying. Seeding the topsoil stockpiles with native grasses and forbs, including vigorous rooting and nitrogen fixing plants such as alfalfa, will be done to prevent erosion and also improve the fertility and physical tilth of the soil. The topsoil removal area at any one time shall be minimized to prevent both wind and water erosion. • Peabody does not propose to use any selected overburden or interburden materials as topsoil substitutes or plant seedbed media. This is based on results of the soil survey 21-29 Revised 08/19/88