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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. Along the crop line in the NHN Mine area, some box cut <br />overburden material will initially be temporarily stockpiled outside of the area mined (see Map <br />2.05.2-1). This box cut material will be stockpiled in the south of the permit area and is available <br />for backfilling at the end of mining or at any other time to backfill the mining pit. The height of <br />the overburden stockpile will vary with a maximum 1.4H:1 V side slope, which represents the <br />angle of repose of the material. All stockpiles will be constructed to ensure stability of the fill <br />and to comply with the effluent limitations of Rule 4.05.2. Map 2.05.4-1 illustrates the projected <br />reclamation contours for the permit area. Backfilled material will be placed to minimize effects <br />on post -mining vegetation and ground water, minimize off-site impacts and support the approved <br />post -mining land use. Upon completion of the backfilling, all areas disturbed by mining will be <br />graded to a smoothed landform that approximates pre -mining topography (see Map 2.05.4-1). <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. An extension to the 180 day requirement for completion of backfilling and grading, <br />as outlined in Rule 4.14.1(1)(c), is needed at NHN. Backfilling and grading activities are <br />ongoing and it is anticipated it will take longer than 180 days to complete based on equipment <br />and manpower availability. Backfilling and grading as well as other reclamation activities are <br />expected to be completed as outlined in Table 2.05.4(2)(a)-1, Reclamation Time Table. <br />Final Grading: Prior to topsoil replacement, Bench 1 will be scarified by ripping on the contour <br />to reduce excessive compaction, prevent potential slippage zones, reduce erosion and improve <br />water and air movement and root growth across the Bench 1/overburden interface. If such <br />grading is hazardous to equipment operators, then grading will be done in a direction other than <br />generally parallel to the contour. <br />Section 2.05.4(2)(c) Page 1 March 2018 (TR -16) <br />