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• 3.0 SIIBSIIRFACE SOIL CONDITIONS <br />The soil borings indicated that at both sites a thin layer of <br />colluvium overlies sandstone and claystone bedrock along the <br />upper parts of the slope. The lower part of the slope at Cameo <br />Refuse Pile No. 2 consists of alluvial fine to medium sands <br />reaching a depth of over 55 feet at Test Boring No. 2-3. The <br />lower part of the slope at Pile No. 3 also consisted of alluvial <br />fine to medium silty sands ranging in depths up to 25 feet at <br />Test Boring 3-3. At this site, low density sands were detected <br />near the surface but densified rapidly. Groundwater was not <br />observed in any of the test borings, and it appears that the <br />• entire slope and valley fill area are currently dry. Piezometer <br />readings taken by Powderhorn Coal Company recently confirmed that <br />the area is dry. <br />A geologic reconnaissance of the bedrock in the area indicated <br />that the bedrock type is primarily sandstone, but there are <br />occasional shale beds 1 to 10 feet thick. The sandstone is <br />typically fine to medium grained and brown in color. The bed <br />thickness is variable with some thin platey beds and some <br />massively bedded layers 10 to 40 feet thick. The massive beds <br />are infrequently jointed with spacings at 10 to 20 feet. The <br />thin beds are more frequently jointed approximately 1 to 3 feet. <br />The shales in the area are gray to maroon colored clay shales and <br />• were found to be hard and fissle. <br />5 <br />