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The remaining bench remnant shall be graded to ensure that water drains away from the base <br /> of the fill area toward the bench outslope. A depression in the bench and access road <br /> adjacent to the edge of the bench along the north and eastern portions of the area will be <br /> filled using material derived from the bench area. The fill will be constructed so that surface <br /> water runoff drains to the outside of the bench area. It is estimated that 1,000 cubic yards <br /> of material will be excavated and placed for this operation. <br /> Four (4) contour furrows will be constructed on the bench remnant to contain runoff in order <br /> to help prevent drainage from flowing both toward the toe of the fill and toward the mine <br /> bench outslope. These furrows are described, and will be constructed and paid for, under <br /> Task 5, Surface Drainage: Contour Furrows. <br /> Upon completion of backfilling, grading and drainage construction, the bench remnant shall <br /> be ripped to a depth of eighteen (18) inches. <br /> One rolling dip will be constructed on the roadway between the Coal Silo Area and the Lower <br /> Bench area. The location will be marked in the field by the PROJECT MANAGER. The rolling <br /> dip will be constructed and paid for as described in Task 6, Surface Drainage: Rolling Dips. <br /> The remainder of the road between the Coal Silo Area and the Lower Bench Area shall receive <br /> the following treatment: <br /> Existing berms on the outside of the road shall be eliminated. The bermed material shall be <br /> removed to the inside edge of the road. Material shall be placed preferentially, so that any <br /> existing ditches or depressions are filled first. The road shall be graded so that the slope of <br /> the road is to the outside, rather than inside, portion of the road. Material removed during the <br /> grading operation shall be filled on the inside portion of the roads, to facilitate drainage to the <br /> outside of the roads. An estimated 400 feet of the road will receive this treatment. <br /> Task 4k - Lower Bench Area <br /> Material to accomplish backfilling at the Lower Bench Area will be obtained from two sources: <br /> coal fines and similar materials which are in place at the Lower Bench Area; and from the <br /> adjacent bench outslope. Initially, all coal fines and similar materials located outside of the <br /> fill area will be excavated from the Lower Bench and pushed to the highwall. Additional fill <br /> material will then be obtained from the bench outslopes and will be used to cover the coal <br /> fines and similar materials. Fill material will be placed on top of and adjacent to the rubble and <br /> debris placed in this location during Task 2, Demolition. The fill material shall be transported <br /> to the base of the highwall, placed in six (6) foot lifts, and compacted by sheep's.foot roller. <br /> The bench outslopes will be uniformly excavated such that no excavated slope exceeds 2H:1 V <br /> upon completion of the excavation. <br /> Upon completion of the task, the top of the fill will extend twenty five (25) feet above the <br /> highwall bench remnant. The fill will slope away from the high point of twenty five (25) feet <br /> to blend with adjacent hill slopes. The PROJECT MANAGER will mark the twenty-five (25) <br /> feet level, and the approximate outline of the top of the fill slope in the field using paint or <br /> other suitable materials. Cross Section 1 , Lower Bench Area, depicts the approximate <br /> dimensions of the backfill. It is estimated that the length of the highwall to be filled is one <br /> hundred thirty (130) feet. Upon completion, the outslope of the fill shall not exceed 2H:1 V. <br /> 19 <br />