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the individual test sections. A detailed description and <br /> conclusion for each of the test sections follows. <br /> Section i - High thick soil cut in a road and high <br /> thick rock cut in a bench. <br /> This particular test section consisted of excavations <br /> in colluvial soils and rocks of the Lower Mesaverde Group <br /> The original slope of this area was greater than is and in <br /> some areas approached vertical . The overall factor of safe- <br /> ty was probably close to unity (F.S.= 1.0) as indicated by <br /> the long period of time that these excavations had been <br /> standing. Some areas had experienced local seeping of water <br /> at the toe of the slope and severe erosion due to the lack <br /> of adequate vegetation. <br /> The reclamation concept employed here was to round off <br /> the crest of the slope with a dozer and lower the angle of <br /> the slope from greater than 1: 1 to 1.5: 1. The area was <br /> seeded and mulched with the approved 109000' seed mixture <br /> (Photograph 1) . A diversion ditch and berm were con- <br /> structed at the top of the slope in order to prevent any <br /> sheet f 1 ow of water from cascading down the slope. <br /> Conclusions <br /> For medium dense, well sand a conservative angle of <br /> internal friction normally used is 36 to 42 degrees. <br /> Assuming that the actual internal friction of tett section <br /> 1 is 36 degrees, the factor of safety would be: <br /> F.S.= tan / tan i = tan 36 / tan 33 = 1.3 <br /> A physical inspection of this area indicated that the <br /> factor of safety is indeed at least 1.3. The slope was in <br /> remarkably good shape with no indications of erosion or <br /> movement. The toe of the slope showed no indications of <br /> seepage or sloughage. An adequate growth of vegetation had <br /> established itself on the slope, preventing the erosion of <br /> surface material. In order to ensure that no surface ero- <br /> sion occurs before the seed has established itself, it is <br /> the opinion of the authors that the dozer should traverse <br /> the slope where possible, after final grading, n order <br /> create small furrows that will act as miniature check dams. <br /> It is the consensus of the authors that this particular <br /> test section has proven to be a success and represents a <br /> state-of-the-art means of successfully reclaiming similar <br /> areas in Coal Basin. <br /> it <br />