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Backfilling and Grading Methods <br />Section 2.05.4(2)(c) <br />Backfilling and Grading <br />This section addresses the requirements of 2.05.3(6), 2.05.4(2)(c) and 4.14. <br />Mining and backfilling operations at New Horizon North (NHN) Mine will be performed <br />concurrently. A combination of cast blasting and shovel loaded trucks will remove the <br />overburden and parting materials, then haul the material to a previously mined area to be <br />backfilled. <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). The 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 estimated volume of the overburden stockpile <br />is 900,000 bank cubic yards. All vegetative and organic material and topsoil will be removed <br />from the area where overburden material is to be placed. Both the overburden and topsoil <br />stockpile configurations are shown on Map 2.05.3(3) -3. The topsoil pile height is estimated to be <br />35 feet with a 2H:1V side slope. The overburden stockpile is estimated to be 75 feet high with a <br />2H:1V side slope. Stockpiles will be constructed to ensure stability of the fill and to comply with <br />the effluent limitations of Rule 4.05.2. The temporarily stockpiled material will be graded into <br />the mined area and hauled to the final pit area according to the reclamation plan. Map 2.05.4 -1 <br />illustrates the projected reclamation contours for the permit area. Since cast blasting, truck <br />shovel and dozers will be used, backfilling operations will occur concurrently with mining <br />operations. Backfilled material will be placed to minimize effects on post- mining vegetation and <br />ground water, minimize off -site impacts and support the approved post- mining land use. <br />Approximately six months will be needed to complete the final backfilling operations in each of <br />the areas mined. Upon completion of the backfilling, all areas disturbed by mining will be graded <br />to a smoothed landform that approximates the existing, pre -mined landform (see Map 2.05.4 -1). <br />Map 2.05.4 -2 has 4 cross sections which show the pre- mining and post- mining land surfaces. <br />Section 2.05.4(2)(c) Page 1 February 2012 <br />