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In order to achieve the design slope, the upper most 001 pond was drained to <br />accommodate the placement of refuse. During Bid document preparation, it was <br />anticipated that the contractor would excavate about three feet of muck from the base of <br />the dewatered pond, and then begin to encounter relatively solid material which would <br />form a competent foundation for the refuse. However, as the bottom of the pond was <br />excavated it was apparent that the saturated muck was underlain by saturated and highly <br />weathered Mancos Shale. This material appeared to be essentially devoid of structural <br />integrity, and would be insufficient as a foundation. Excavation continued until the hole <br />was below the water elevation of the second 001 pond. That pond was then dewatered in <br />order that excavation of the first pond did not induce inflow from the second. When the <br />excavation reached the approximate elevation of Bear Creek, to the south, the pond was <br />surrounded on the south, east and north by french drains. These drains should serve to <br />cut off ground water flow toward the excavated pond <br />After excavation was complete, a french drain was built to convey any remnant water <br />from the pond excavation away from the toe of the slope. The pond excavation was then <br />filled with two feet of three to four inch rock, which was pushed into the shale at the base <br />of the excavation with a trackhoe, followed by four feet of clean one and one half inch <br />rock. Trommel reject was placed over this material and a Mirafi blanket was placed over <br />this coarse grained material, in order to prevent the coal refuse from infiltrating into the <br />underlying gravels. Filling in this manner brought the foundation up to just below the top <br />of the pond embankment, which could then act as a small buttress for the refuse fill <br />operation. <br />Following completion of the cut and fill, the cut portion of the slope was ripped using a <br />light dozer working horizontally across the slope. Eight to ten inches of topsoil was <br />applied to the slope after ripping operations were completed. <br />After completion of topsoil application, weed free straw mulch was applied at a rate of <br />two tons per acre. A light trackhoe was then used to create thousands of small <br />hummocks on the reclaimed area. The hummocks are approximately thirty inches wide, <br />twelve to fourteen inches across and ten to sixteen inches deep. The hummocks were <br />constructed so that they are no more than thirty inches apart from each other in any <br />direction. These hummocks will severely disrupt the runoff pattern from the face of the <br />pile, thereby minimizing erosion on the reclaimed surface. Construction of the <br />hummocks also incorporates the straw mulch into the soil surface, which will help to hold <br />soil particles in place during snow melt runoff and following rain storms. The extreme <br />roughness of the area should also enhance revegetation potential. Following hummock <br />construction, the area was fertilized and seeded. <br />Approximately 1,200 shrubs were planted at the toe of the reclaimed slope. The eastern <br />half of the toe was planted with containerized shrubs, while the western half was planted <br />using locally obtained willow cuttings. As these shrubs mature, it is anticipated that a <br />natural sediment barrier will be created. Eight hundred trees were planted in clusters <br />6