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RECLAMATION - BENCHES <br /> The test section consisted of excavations in colluvial soils and rock of the <br /> Mesaverde Group. The original slope of the area was greater than 1:1, and <br /> in some areas approached vertical. <br /> A low buttress was placed at the toe of the buttress, then contoured to serve <br /> as the catching space for rock fall. The area was then seeded and mulched. <br /> Conclusions. <br /> Inspection of the area indicated the factor of safety is 1.3. The toe of the <br /> slope showed no indications of seepage or sloughage. <br /> Section 2. High Thick Fill. <br /> The bench fills were constructed by pushing material over the crest of the <br /> bench. Slopes in these areas often exceed 1:1. <br /> The reclamation concept employed was to flatten the overall slope to 1.5:1 <br /> by dozing the material downslope. In areas where it was impossible to <br /> achieve a slope fo 1.5:1, it was necessary to pull material up the slope. A <br /> berm and diversion ditch were placed at the crest of the fill. A final <br /> procedure was the placement of a small bench and catchment basin at the <br /> toe of the slope, where possible. When the final configuration had been <br /> achieved, the section was seeded and mulched. <br /> Conclusions. <br /> The factor of safety achieved by reducing the slope to 1.5:1 is 1.3. There <br /> was no evidence of incipient tension cracks near the crest of the slope, nor <br /> any seeps on the face of the slope. In addition, there was no evidence of <br /> erosional problems anywhere on the test section. Very small rills and gullies <br /> were noted that could be eliminated by traversing the slope after final <br /> grading by the dozer. The small bench and basin at the toe of the slope <br /> appeared to function very well, both in the sense of stabilizing the slope and <br /> impounding surface runoff from the slope. <br /> Section 3. Thin Sliver Fill. <br /> The test section was placed in an area where a minor amount of material <br /> had been casted down the slope of a mine bench or road cut. The fill itself <br /> is very thin, usually not more than a few feet thick, and does not comprise a <br /> structural fill in itself. Rather, these areas are more like a spoils pile. These <br /> fills were dumped on very steep slopes and the foundations were not <br /> prepared. <br /> 7 <br />