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quantity limitations imposed by previous mining at New Horizon #2 Mine. The meximnm-slope <br />in varies from shallower t hisarea-iaan 3H:1 V to 5H:1 V, with a few exceptions, which is very good <br />for the post mine land use of dry <br />Mining at New Horizon #2 is a standard strip pit operation. Initial topsoil is stripped and salvaged <br />for reclamation, upper overburden is removed by mobile equipment, lower overburden is drilled and <br />blasted, and then overburden is removed from above the coal seam and placed behind the pit into <br />the void of the previous mining area. This process can be seen in Map 2.05.3 -1 in Section 2.05.3 <br />below. This is a highly efficient process for both mining and reclamation, as it reduces the need to <br />transport large amounts of overburden to and from any storage piles as well as minimized the <br />amount of previous pit that is not backf Iled. <br />The coal seam at New Horizon #2 Mine is at a relatively consistent depth from the surface, but the <br />length of the each pit can vary significantly. This becomes more pronounced as the mine reaches <br />it's current western extent. As can be seen on Map 2.05.4 -1 -2, the pit length (north to south) will <br />reduce from over 1400' to 750'. This means that there will be less overburden created by new <br />mining than there is void space in previous mining strips. In order to make up for some of the <br />discrepancy, and to insure that lands not owned by Western Fuels are returned to approximate <br />original contour, material will be hauled from active mining areas to mined out areas that need <br />additional backfill. Attachment 2.05.4(2)(c) -7 shows the sequence of mining and hauling that will <br />be used to re- establish appi oxi nate up 1 I.Mourt he new t000craohy on Morgan, Lloyd and <br />Benson properties. <br />Thin and Thick Overburden. <br />The New Horizon 2 permit area does not meet the requirements of either the thick or thin <br />overburden as shown by the following calculations: <br />103.96' maximum stripping depth <br />79.93' average overburden <br />7.94' Combined Upper and Lower Dakota <br />(nemed July 2006) 2.05.4(2)(c) -7 <br />