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^ <br /> . . <br /> Section Z Hz h tbi k *iil in a road and mine bench <br /> [hese tvpes, of areas were constructed using prudent <br /> state-of-the-art construction techniques practiced at the <br /> time o+ excavation' The road fill was constructed in areas <br /> where excessive material was side cast down the bank' <br /> Vegetation was not removed, nor was the fill compacted or <br /> keyed into the hillside. 'The mine bench fills were <br /> constructed by pushing material over the crest of the bench <br /> in a similar manner' Slopes in these areas often exceed <br /> 1 : 1 ' Local erosion had occured due to water running over <br /> the crest and down the slope. <br /> The reclamation concept employed here was to flatten <br /> the overall slope to 1.5: 1 by dozing the material down- <br /> slope' (Photograph 2) . In areas where it was impossible to <br /> achieve a slooe of 1 '5: 1r as indicated in fiqure B, it was <br /> necessary to pull this material up the slope and dispose of <br /> it in an approved location' The final configuration was <br /> subsequently seeded and mulched' A berm and diversion ditch <br /> were placed at the crest of the fill ' A final procedure was <br /> the placement of a small bench and catchment basin at the <br /> toe of the --lope, where possible~ <br /> Conclusions <br /> As previously discussed, the factor of safety achieved <br /> by reducing the slope to 1'5: 1 is 1 '3' A close inspection <br /> of this test section indicated no evidence of incipient <br /> tension cracks near the crest of the slope nor any seeps on <br /> the face of the slope. In addition, there was no evidence <br /> of erosional problems anywhere on the test section. Very <br /> small rills and gullies were noted that could be eliminated <br /> by traversing the slope after final grading by the dozer' <br /> The small bench and basin at the toe of the slope appeared <br /> to function very well , both in the sense of stabilizing the <br /> sIope and impounding surface runoff from the slope due to <br /> erosion before the vegetation had established itself ' <br /> However , this procedure should only be applied to the mine <br /> benches and not to the haul roads, as construction of <br /> benches and catchment basins in similar areas of the haul <br /> road would cause more harm to the environment as compared <br /> to the small stability benefits' <br /> it appears that this test section was a complete succ- <br /> ess and should continue to be a part of the post-mining <br /> reclamation plan. <br /> Section 3 - Thin sliver fill <br /> This test section was placed in an area where a minor <br /> amount of material had been casted down the slope of a mine <br /> bench or road cut. The fill itself is very thin, usually not <br />