2014-11-21_PERMIT FILE - C1996084 (23)

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• Rule 2.' Permits communities. These are well drained soils with slow to moderately rapid permeability. The water erosion hazard is very high, and the wind erosion hazard is slight to high. A typical profile includes a surface layer with 4 to 6 inches of very channery clay loam, channery silty clay loam or sandy loam. The subsoil, where present, consists of 32 inches of channery silty clay loam. The substratum, where present, is 9 to 12 inches of clay loam, clay, and/or sandy loam. Depth to bedrock is from 14 to 38 inches. Soils Analysis Samples collected from 14 representative pits during the July 1996 investigations were analyzed for the following physical and chemical characteristics: texture (by hydrometer), saturation percentage, sodium adsorption ratio, pH, electrical conductivity, organic matter, calcium, magnesium, sodium, boron, and selenium. Results are presented in Exhibit 9. Lab results of texture analyses were used to adjust textures originally estimated in the field using visual and tactile means. The lab results were compared with topsoil and overburden suitability guidelines for Wyoming and Montana. These guidelines are generally applicable to Colorado which has no state suitability guidelines. There appear to be few chemical limitations for salvage and use of project area soils • for reclamation. The pH for all samples ranged from 5.9 to 8.0, which is well within the acceptable range (5.5 to 8.5). The highest specific conductivity reading was 3.42 mmhos/cm which is below the level of concern (4.00). The highest SAR (sodium adsorption ratio) measured was 7.2 (values less than 10 are generally suitable). Soluble selenium levels were all 0.06 ppm or less, well below the 0.1 ppm level of concern. All samples had boron levels below 5 except one (113-A had a soluble boron level of 5.00 ppm). Levels of 5 or greater are considered unsuitable by both Montana and Wyoming. Suitability of Soil Horizons as Plant Growth Media The permit area contains deep soils in the Lorencito and Cow creek valleys. These soils generally have favorable textures for reclamation. Upland soils are a mixture of unusable shallow, excessively stony or cobbly soils as well as relatively deep soils with favorable textures for reclamation. Shawa Loam, 5 to 15 percent slopes (map symbol CeD) has 36 to 60 inches of salvageable soil. The texture is generally clay loam or sandy clay loam. In some areas, a very gravelly content below 36 inches will limit salvage depth. PERMIT.a'IS~December 20, 1996 2.04-42