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natural slope is steeper than 3:1. The highwall reduction area and spoil will be worked togs•ther to <br />minimize that material reduced and 1o shape and blend the material into the natural topography, • <br />creating a transition that prevents drainage from creating knickpoints, propagating natural undisturbed <br />slopes, and enhancing the post mining land use, <br />Thin or thick overburden as defined b•/ Section 4.14.4 and 4.14.5 does not exist at the Yoast Mine. <br />The final volume is greater than 0.8 of the initial volume, therefore the thin overburden criteria ~s not <br />applicable. The thick overburden rule does not apply because the final volume is not greater than 1.2 <br />of the initial volume. Please refer to the volume calculations on Table 20-1, Post Mining Lan,jform <br />Mass Balance. <br />Box cut spoil will initially be placed onto unmined land as described in Tab 12, Coal Resource Recovery <br />~ Plan. This material will be rehandled when the dragline returns to the box cut arealsl. Portions of box <br />i cut spoil will he temporarily stored in approved locations above [he highwall for backfill into portions of <br />the final pits. All vegetative and organic material and topsoil will be removed from the area where box <br />cut spoil is placed, and the spoil graded both into the mined area and blended into the surrounding i <br />terrain. No material shortages or excessive disturbed areas are anticipated in the area of the final <br />highwall or major spoil excesses in [he box cut area. This can 6e determined by reviewing Exhibit 12- <br />1, Operations Plan, and the pre- and post mining topography slopes as shown on Exhibit 20-2P., Pre- • <br />Mining and Post Mining Cross-sections. <br />Surface treatment of graded spoil is discussed in Tab 21, Minesoil Reconstruction. Small depressions <br />are not planned at this time; however, if small depressions are needed to conserve moisture, minimize i <br />erosion, create and enhance wildlife habitat or assist revegetation, plans will be submitted for apiproval <br />prior to construction. Terraces are not planned for the Yoast Mine. <br />SCC does not anticipate any grading problems but shall monitor the success of the 6ackfilling and <br />grading program at least annually. This monitoring will include visual inspections of areas graded to <br />determine progress of grading activities and any settling of graded areas. In addition to visual <br />monitoring, a topographic map will be generated fiom photogrammetric methods of areas backfilled II <br />and graded on an annual basis. This topographic map will be evaluated [o determine if the final graded <br />topography is consistent with the proposed past mining topography and land use. The topographic <br />map will <br />• <br />2 Revised 2199 <br />