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RECLAMATION - BENCHES <br /> Geo-Hydro's Documentation: <br /> No. 5 Bench runs approximately 1,500' east and west, and consists of a cut <br /> on the south and a fill on the north side. The cut ranges from 25' to 175 ' in <br /> height. Most of the cut is in colluvium, typically 50' in height, and is <br /> characterized by major sloughing and mudflows. Areas of seepage are <br /> common. The west end of the cut is in Mesaverde sandstone and shale. <br /> The rock cut is subject to moderate rockfall and minor sloughing. Cut <br /> slopes vary from 450 to 900 locally, and average 500 to 600 overall. A large, <br /> recent slough slide is present in the colluvium nearest the portal, and has <br /> severely undercut the crest of the cut. <br /> The fill slope below the west end of the bench is up to approximately 100' <br /> high, at a slope of 350. Outwash from the fill is present along the valley at <br /> the toe of the fill. Rills are common on the bench and fill slope. Minor fill <br /> along the road and along the east portion of the bench is 10' to 30 ' in height. <br /> An avalanche run crosses the mine bench at the location of the portals, at <br /> the western end of the bench. A very large avalanche gully is adjacent to <br /> the east end of the bench. The extreme east end of the bench and the road <br /> below may be covered by snow debris from this gully. <br /> Reclamation - Application of Methods <br /> A buttress will be constructed along the toe of the cut in order to increase the <br /> cut's long-term stability. <br /> Buildings still remaining at the site on closure of the mine, as well as <br /> foundations, will be utilized in construction of the buttress. The foundations will <br /> be rubblized and, together with the dismantled structures, placed against the <br /> toe of each cut, along the length of the toe, together with any rock and/or soil <br /> which has fallen from the crest of the cut. <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. The height of <br /> the cuts themselves, and the steep natural terrain beside the cuts precludes <br /> 15 <br />