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• Phase II, which will mine Segments F-1 through the north end of the mine, will begin <br />at this time with mining continuing in anorth-northeast direction upon the opening of a <br />steady state pit. However, these Lifts will not be discussed, as was the first Lifts in the <br />North Pit, during Phase I of the operations, because mining will continue through the <br />canyon on an east-west plane under asteady-state haulback system. This is necessary <br />because the overburden above the Lewis seam is very shallow on the west side, the <br />North Pit, and must be mined concurrently with the overlying Shamrock Rider, <br />Shamrock and Carbonera seams in the upper reaches of the main pit. <br />Over~urtien <br />This section has been established to accurately describe the movement of the <br />overburden through development of a steady-state pit. The steady-state pit will employ <br />the haulback of overburden to the existing pit from which coal has been removed. As <br />shown on Figure 5-1, three general lifts for overburden will be referred to in each of <br />the coal removal segments. Crushed rock and gravel operations pursuant to a separate <br />permit application may be conducted adjacent to "lift 1 ". <br />As described in Table 5-1, overburden will be removed from Segment A-1 and moved <br />to the box cut spoil area southwest of the pit. Accordingly, lifts for Segments B-1 and <br />C-1 will be mostly removed to the box cut spoil azea with the exception of some <br />overburden from Lift 3 of Segment C-1, which will likely stay in the B-1 area. In like <br />manner, the next lifts will be placed in the locations opened by the previous cuts as <br />shown on Table 5-1. <br />It is estimated that the volume of the steady-state pit will be approximately one million <br />cubic yards. The maximum highwall height is anticipated to be 180 feet. Backhaul of <br />overburden material will begin Phase II. The accurate visual expression of the <br />maximum open pit has been shown on Map 5-fi. The steady-state pit will be developed <br />from coal Segments C-1, D-1 and parts of E-1. The overburden has been placed in the <br />box cut spoil area in a uniform method with the largest amount of overburden being <br />placed on the eastern edge of the area. The amount of fill necessary to reclaim the <br />maximum open pit for Phase I will be 850,000 cubic yards of material. <br />It is expected that the massive sandstones overlying the Lewis seam will be placed <br />mostly at the bottom of the pit with the remaining silts, sands, and shale, placed on top <br />of the sandstone spoil. Salvaged soil that has been removed in advance of overburden <br />removal, will be directly redistributed over the regraded area, in sequence with mining, <br />as much as possible. Very early in Phase II, all of the suitable soil will be removed <br />fmm the bottom of the canyon in the azea along the north-south axis of Sections 2 and <br />3. This will be done in both lifts to prevent topsoil contamination by spoil, or <br />• <br />Technical Revision 08 (v 1.3) 5-7 Revised 9/1997 <br />