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2.05.3 <br />The capacity of the coal mine waste disposal area is about 38,000 cubic <br />yards. The pile is approximately 30 feet high. The side slopes of the pile will <br />be no steeper than 3h:1 v No underdrain system will be installed. Rule <br />4.09.1(13) requires that an appropriate underdrain be installed if seeps, <br />springs or waterways, natural or manmade, are in the coal waste disposal <br />footprint area. At the time of this writing, no seeps, springs, or waterways, <br />natural or manmade are identified in the coal waste disposal footprint area. <br />The site is to be inspected for springs or seeps as work progresses, and an <br />underdrain installed only for cause. This would be an alternate design as <br />permitted under Rule 4.09.1(3) and 4.10.3(5). <br />Coal mine waste will be placed and compacted to 90 percent of its maximum <br />dry density to prevent spontaneous combustion and to provide the strength <br />required for stability of the coal mine waste pile. Dry densities will be <br />determined in accordance with AASHTO T99-74. Compaction will be <br />performed with a variety of equipment which is operated by experienced <br />operators. The compaction specification may be attained by wheel rolling <br />the coal mine waste with a front end loader or water truck. A self propelled <br />soil compactor may be used such as a Cat 815 or 825. Alternatively a pull <br />behind sheepsfoot roller may be utilized. Any equipment that can compact <br />the coal mine waste and achieve the compaction specification may be <br />utilized. The placing and spreading of the coal mine waste will be started at <br />the lowest point of the foundation. The coal mine waste will be keyed into <br />the natural ground. Materials will be spread in approximately horizontal lifts <br />no more than 24 -inches thick, and such lifts made uniformly over long <br />stretches. Each lift will be moistened or dried to a uniform moisture content <br />suitable for maximum compaction. Compaction will be carried to the edge of <br />the fills so that the final slopes are firm. The pile shall be graded in a matter <br />to avoid runoff over the face of the pile and/or ponding of water, and interim <br />ditches, if required, will be constructed according to final ditch specifications. <br />If standing water develops after the pile has been over -excavated and before <br />coal waste has been placed in the pile, the water will be pumped into the <br />sediment pond. <br />Compaction tests will be taken at a frequency and location of not less than <br />one per every other layer, at random locations across the pile. Test locations <br />and results will be reported to the Division in the appropriate construction <br />reports. <br />The coal mine waste pile area will be inspected for stability by a qualified <br />registered engineer or other qualified professional specialist experienced in <br />construction of earth and rockfill embankments under the direction of a <br />PR -02 2.05-29- 10/12 <br />