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materials. A cement plug will be powed from ten feet below grade to within approximately three feet of the surface. <br />The remaining three feet will be filled with soil and graded to blend with the surrounding terrain. <br />C As noted on page 2.05-45.5, any required presswe-grout boreholes will be sealed at the time of construction. <br />Cement grout will be pumped through the boreholes to seal any wet zones encountered and the boreholes will be <br />filled with grout and allowed to set-up on completion of grouting operations. Any surface casing extending above <br />ground surface would be cut-off flush with or below natural ground level. Utility boreholes will be plugged, filled to <br />within 10 feet of the ground surface with inert material, and a cement plug will be powed from the top of the fill to <br />within approximately 3 feet of the surface. Any surface casing will be cut-off below grade, and the remaining hole <br />will be filled with soil material and graded to blend with the surrounding terrain. <br />Following removal of structwes and equipment, and plugging and sealing of the shaft and boreholes, any cuttings <br />remaining in the temporary mine waste disposal pit will be covered with excavated shaft collaz material; road culverts <br />will be removed and disposed of off-site; road-base and surfacing materials will be removed and placed on the shaft pad; <br />and the shaft pad and access road distwbance azeas will be regraded to reestablish effective drainage and blend with the <br />surrounding terrain. Cover over any cuttings remaining in the cuttings pit will be a minimum of 2 feet of suitable <br />material, and the postnining configuration will approximate the pre-mining contours. As-built certification will be <br />provided to the CDMG following fmal closwe, backfilling, and grading of the cuttings pit. Any excess road-base and <br />surfacing materials not required to reestablish approximate original contow will be hauled off-site and disposed of. <br />Stockpiled and windrowed topsoil will then be replaced on those disturbed azeas where it was previously removed and <br />seeded with a pastweland seed mixture. ~ <br />OVERLAND BELT MAGNET (MR02-179) ~ <br />When the overland belt is no longer needed, it and its associated sVuctwes will be dismantled and removed from the <br />property. The concrete piers will be demolished to three feet below grade and the concrete will be hauled to the pit for <br />burial. The metal from the framework will be recycled and the~rnagnet offered to sister companies for use. The concrete <br />pad will be demolished and hauled to the pit for burial. The azea then will be graded and reclaimed as per the previously <br />C approved plan. <br />Soil Stabilization Plan <br />Proper site prepazation and soil handling strategies will be utilized to control wind and water erosion. The <br />movement and manipulation of topsoil materials in a moist condition minimizes wind and water erosion. As <br />explained by Bauer et al. (1976), a protective surface seal develops as silt and clay fractions bond together after <br />reapplication of topsoil. This phenomenon is attributable to the rapid evaporation of surface moistwe from <br />redistributed soil materials. <br />Distwbed azeas will be subjected to final grading, but will remain in a rough condition to assist stability and resist <br />slippage of topsoil after reapplication. Leaving the graded surface in a roughened configuration also improves <br />moistwe permeability between the spoiUtopsoil interface (Bauer et at. 1976). Scrapers will reapply topsoil along the <br />contow whenever possible. The tracks made by scrapers create a "terracing" effect that helps to reduce overland <br />surface flow and the potential loss of topsoil. Following topsoil reapplication, but before seeding, the topsoil will be <br />graded to inswe a uniform and stable thickness which will be consistent with the reclamation and revegetaion <br />requirements. <br />Prior to seeding, which will be initiated as soon as practical after final grading, topsoiled sites will be chisel-plowed <br />in order to alleviate compaction and promote water infiltration. Chisel-plowing has been a highly effective means of <br />temporary stabilization prior to vegetation establishment. Dollhopf et al. (1977) reported that chisel-plowed topsoil <br />at the Savage, Beulah and Colstrip Surface Mines were only surpassed by the radical treatment of dozer basins in <br />reducing overland water flow from reclaimed mine sites. The water detention capacity of chisel-plowed topsoil is <br />reported by Dollhopf et al. (1977) as 176,4001iters per hectaze, or 2,521.3 cubic feet per acre. <br />Another stabilization technique which serves to minimize erosion is contow fun•owing. Distwbed ]and within the <br />proposed permit azea will be contow furrowed following seeding. Atypical cross section of a contow furrow is <br />TROS-48 2.05 - 106.1 04/25/05 <br />