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Backfilling and Grading <br />This section addresses the requirements of Rules 2.05.3(6), 2.05.4(2)(c) and 4.14. <br />Backfilling Methods <br />Mining and backfilling operations at the New Horizon North (NHN) Mine are performed <br />concurrently. A combination of cast blasting and shovel loaded trucks remove the overburden <br />and parting materials then haul the material to a previously mined area to be backfilled. Refer to <br />Map 2.05.3-1 Typical Cross -Section of Mining and Reclamation for an illustration of the <br />backfilling methods utilized at NHN. <br />Along the crop line in the NHN Mine area, some box cut overburden material will initially be <br />temporarily stockpiled outside of the area mined (see Map 2.05.2-1). This box cut material will <br />be stockpiled in the south of the permit area and is available for backfilling at the end of mining <br />or at any other time to backfill the mining pit. The overburden stockpile ranges from 95-130 feet <br />high with a maximum 1 AH:1 V side slope. These maximum side slopes represent the angle of <br />repose of the material. All stockpiles will be constructed to ensure stability of the fill and to <br />comply with the effluent limitations of Rule 4.05.2. <br />Map 2.05.4-1 illustrates the projected reclamation contours for the permit area. Backfilled <br />material will be placed to minimize effects on post -mining vegetation and ground water, <br />minimize off-site impacts and support the approved post -mining land use. Upon completion of <br />the backfilling, all areas disturbed by mining will be graded to a smoothed landform that <br />approximates the existing, pre -mined landform (see Map 2.05.4-1). Map 2.05.4-2 has four cross <br />sections which show the pre -mining and post -mining land surfaces. <br />General Grading Requirements <br />Dozers will be utilized for grading of overburden, Bench 1, and topsoil at NHN as illustrated on <br />Map 2.05.3-1 Typical Cross -Section of Mining and Reclamation. <br />Final Pit Backfilling: In order to eliminate any final highwalls and to achieve the approximate <br />original landform, some highwall material will be pushed or dozed into the mined area. Map <br />2.05.3-1 shows typical cross sections of the fill material placed into the mined pits. Material <br />above the final highwall may be blasted or ripped and then graded to blend into the surrounding <br />topography. <br />Final Gradin: Prior to topsoil replacement, Bench 1 will be scarified by deep ripping on the <br />contour to reduce excessive compaction; prevent potential slippage zones; reduce erosion; <br />improve water and air movement; and root growth across the Bench 1/overburden interface. If <br />Section 2.05.4(2)(c) Page 1 April 2016 (PR -01) <br />