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RECLAMATION - BENCHES <br /> • The mine bench cuts have been excavated either in the Mesaverde bedrock <br /> or in colluvial soils. In either case, they were excavated at steep slopes, <br /> steeper than 450' Such steep slopes may be appropriate for the bedrock, <br /> but cuts in colluvial slopes may experience some stability problems. <br /> • The mine bench fills were constructed in a similar way to the road fills. The <br /> foundations for the fills were not stripped of vegetation (if any), topsoil was <br /> not removed, and no keying of the fills into the foundations was applied. <br /> Very probably, the fills were not compacted. The fills can, therefore, be <br /> classified as loosely dumped fills. <br /> • The configurations of the fills depend very much on the topographic <br /> conditions of the site (similar to the haul road fills). On steep natural slopes, <br /> the fill material is spread out for a large distance below the mine bench <br /> elevation. The "height" of such fills, although not accurately known, is very <br /> probably limited to several feet only. Occasionally, vegetation can be <br /> observed protruding through such fills. <br /> • The material of the fills is a mixture of soils and rocks. Larger size boulders <br /> of sandstone frequently roll down the slope for a considerable distance. <br /> They cover the area below the toe of the fill. <br /> • On flatter slopes, or on slopes where the gradient decreases downslope, the <br /> thickness of the fill may be considerably larger than on the above described <br /> "sliver"-type fills. Thicker fills may then become a part of the mine bench. <br /> Potential stability problems of these two fill types are different. Thin, <br /> sliver-type fills do not experience serious stability problems, except for <br /> shallow sloughing and locally severe erosion problems. Thicker fills have <br /> been, in all probability, subject to considerable settlement. They may also <br /> experience potential stability problems (deeper failures) as can be seen by <br /> infrequent tension cracks located close to the mine bench crests. <br /> RECLAMATION PROBLEMS <br /> As indicated in the Geo-Hydro study: <br /> • Minimal or no reclamation efforts will be required along sections that are free <br /> of geotechnical hazards or contain moderate stability problems. Special <br /> reclamation methods will have to be applied within sections containing <br /> important stability problems. <br /> 4 <br />