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RECLAMATION - BENCHES <br /> Material will then be placed over the rubble, compacted and contoured. Rock <br /> from the crest of each cut will be allowed to fall on the buttress. It is anticipated <br /> that material from reclamation on the fill at the bench will be utilized in <br /> constructing the buttress for the toe. <br /> The dimensions of the buttress will be determined by considerations of stability, <br /> so as to allow a factor of safety of 1.3. <br /> Further disturbance to the crest of the cut is not contemplated. <br /> Around the perimeter of the bench, the angle of the edge will be flattened to a <br /> slope of 1.5:1, or flatter. Material taken from the perimeter of the bench will be <br /> used in construction of the buttress along the cut. <br /> In order to increase the stability of the fill, a berm will be constructed above the <br /> flattened slope around the outside perimeter of the bench. Further back, and <br /> within the flattened area of the bench, a small ditch will be constructed. The <br /> objective is to improve surface drainage so as to prevent surface water from <br /> entering the fill. <br /> The entire area of the bench will be scarified and seeded with the approved <br /> 10,000' seed mix. <br /> No. 4 Bench <br /> Geo-Hydro's Documentation: <br /> No. 4 Bench is almost entirely cut from Mesaverde sandstone and shale. <br /> Areas of ponding are frequent on the irregular bench surface. The bench <br /> cut south of the mine bench is approximately 100' high, at a slope of <br /> approximately 750 to 800. Up to 10' of colluvium is present at the top of the <br /> cut. The cut is subject to moderate rockfall. <br /> A small amount of shallow fill is present along the east side of the bench. <br /> The north fill is up to approximately 300' in height, at a slope of 350 to 450. <br /> The fill is probably a shallow sliver over its lower portions, although it is <br /> probably of significant thickness at the crest of the bench. A flatter area of <br /> outwash is present at the toe of the fill. Severe erosion and sloughing is <br /> present on the fill surface, where several large gullies have formed. Cracks <br /> were observed approximately 20' behind the crest of the fill. A small cubic <br /> structure near the cracks has settled up to 6". <br /> 13 <br />