2015-04-02_PERMIT FILE - M2015017 (4)

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SOILS INFORMATION - EXHIBIT I The following resources were used in developing soils information: - Soil Conservation Service (SCS). 1976. Range Site Description for Dry Mountain Outwash (Code 316) . - Soil Conservation Service (SCS). 1976. Range Site Description for Mountain Outwash (Code 311) . - U.S. Dept. of Interior (1950), Gold Placers and their Geologic Environment in Northwestern Park County, Colorado, U.S.G.S. Bulletin 955 -D. Undisturbed soils in the permit area generally exhibit profile development to depths of 12 to 24 inches. Residual soils in the these areas have A horizons that are approximately four to six inches of dark brown sandy loam or loam. These soils have a light brown surface that is very gravelly. However,the gravels are usually in the fine gravel range (4mm to 20mm) instead of exhibiting the full rangeof gravels. The soils over the area have B horizons about seven to ten inches thick usually of sandy loam, sand or loamy sand textures. Parent materials are generally from quaternary glacial till and alluvium, the most common are gneisses. The weathering of this material has lead to the development of the generally sandy soils and cobbly profile occurring on site. The C horizon including weathered bedrock and gravel is encountered within 24 -36 inches from the surface. The placer mining in the area started in the 1860's and was intermittent through the years. No topsoil was ever salvaged from these activities. The exact extent of the pre -law disturbance is unknown but it was likely between 15 -20 acres. In all of the disturbed areas shown, not a trace of topsoil was salvaged and the vast majority of the areas have washed gravels on the surface with very little fines and natural vegetation has been extremely slow in reclaiming the land, although there are a few patches of volunteer evergreens. Rooting materials are very scarce. The gold bearing gravels located in this area are primarily glacial in origin. These gravel deposits are judged to be the lateral and possibly some terminal moraines left by the last retreating glaciers appear to be largely unchanged by subsequent erosion actions east of the river. West of the river, where stream action and man have destroyed the distinctive structures of the gravel deposits, sands in the Alma Sullivan Aggregate Pit March 2015 I -1