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4 . 51 <br />USDA texture influences available water capacity and erodibility by wind or water. Texture <br />also influences soil structure, consistence, water intake rate, runoff, fertility, workability, and <br />trafficability. Potential slippage hazard is related to soil, texture, and although other factors also <br />contribute, the ratings of soil texture represent one important factor (USDA, 1978). Soil textures <br />are rated good to fair for soils in the permit area, but are generally not considered the limiting <br />factors. The alluvial lands soils are too sandy in the substratum and are rated poor below two <br />inches. The textures of the roadfill material are rated fair in both samples. <br />Coarse fragments influence the ease of excavation, stockpiling, respreading, and suitability <br />for the final use of the land. A certain amount of coarse fragments can be tolerated depending <br />upon the size and the intended use of the reclaimed area. If the size of rock fragments exceed <br />ten inches, the problems are more severe (USDA, 1978). Coarse fragments are evaluated <br />based on pedon descriptions for soils on site. Most soils are rated good throughout. Few <br />horizons tested have more than 15 percent coarse fragments larger than three inches and are <br />rated fair. No soils are rated poor for coarse fragments. <br />• 4.4.5.4 EVALUATION OF SURFACE MATERIAL ON MINE BENCHES <br />In response to Stipulation Number 6 attached to the original permit, Grand Valley submitted <br />a composite analysis of the surface material at the McClane Canyon Mine site. The analysis <br />indicated "slightly elevated SAR levels at both sites, and elevated salt level at McClane Canyon, <br />and a very high pH at Munger Canyon." (CMLR 8,9,85) <br />A second series of samples were taken at McClane Canyon to determine if the elevated <br />levels of SAR and salt were concentrated in the surface layer and would necessitate special <br />handling of the surface layer during reclamation. The samples were taken on August 6,1985 <br />from four locations on both the upper and lower benches. After the samples were collected <br />they were combined and split to yield a sample from both benches. Shown below are the <br />results of sampling. <br />Original Sample Upper Bench Lower Bench <br />PH 8.4 7.25 7.4 <br />SAR 5.5 2.12 1.32 <br />. Soluble Salts 6.0 3.70 3.4 <br />(by conductivity) <br />M~ Volume 1 4.29-96 <br />