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Steep Slopes. New Horizon Mine does not have steep slopes as defined in the regulations. <br />Final Grading. Final grading and preparation of the backfilled material before placement of <br />topsoil material will be done along the contour to minimize subsequent erosion and instability. If <br />such grading is hazardous to equipment operators, then grading will be done in a direction other <br />than generally parallel to the contour. <br />Final Pit Backfilling. The final pit is located at the western edge of the permit area on WFC - <br />Johnson property. In order to eliminate any final highwalls and to achieve grading that is <br />conducive to the post mine land use, all stockpiled highwall material will be pushed or dozed <br />into the final mined area. Map 2.05.4-1 shows cross sections of the fill material placed into the <br />mined pits. Material above the final highwall may be blasted or ripped and then graded to blend <br />into the surrounding topography. <br />Western Mining Area Backfilling The post mine topography of the western mining area will <br />be a combination of approximate original contour (Morgan, WFC -Benson West, and WFC - <br />Lloyd property) and modified original contour (WFC -Johnson property). This can be seen on <br />Map 2.05.4-1. The modified original topography on the WFC owned land is due to backfill <br />quantity limitations imposed by previous mining at New Horizon #2 Mine. The slope varies from <br />shallower than 3H:1 V to 5H:1 V, with a few exceptions, which is very good for the post mine <br />land use of dryland pasture. <br />Mining at New Horizon #2 is a standard strip pit operation. Initial topsoil is stripped and <br />salvaged for reclamation, upper overburden is removed by mobile equipment, lower overburden <br />is drilled and blasted, and then overburden is removed from above the coal seam and placed <br />behind the pit into the void of the previous mining area. This process can be seen in Map 2.05.3- <br />1 in Section 2.05.3. This is a highly efficient process for both mining and reclamation, as it <br />reduces the need to transport large amounts of overburden to and from any storage piles as well <br />as minimize the amount of previous pit that is not backfilled. <br />The coal seam is at a relatively consistent depth from the surface, but the length of the each pit <br />can vary significantly. This becomes more pronounced as the mine reaches its current western <br />extent. As can be seen on Map 2.05.4-1-2, the pit length (north to south) will reduce from over <br />1,400' to 750'. This means that there will be less overburden created by new mining than there is <br />void space in previous mining strips. In order to make up for some of the discrepancy, and to <br />insure that lands not owned by WFC are returned to approximate original contour, material will <br />be hauled from active mining areas to mined out areas that need additional backfill. Attachment <br />2.05.4(2)(c)-7 shows the sequence of mining and hauling that will be used to re-establish the new <br />topography on Morgan, WFC -Lloyd and WFC -Benson West properties. <br />Revised January 2016 (TR -70) 2.05.4(2)(c)-2 <br />