2014-08-14_PERMIT FILE - M2014027 (3)

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Permeability is moderately rapid. The effective rooting depth is 60 inches or more and available water capacity is moderate. Surface runoff is slow and erosion hazard is slight. Water tables occur at one and one -half to two and one -half feet below the surface during the spring snow melt season. Flooding occurs for brief periods in the spring in some places. TOLMAN -ROCK OUTCROP COMPLEX These gentle to steep (nine to 65 percent) slope soils occur on mountain and foothill side slopes at elevations of 8,100 to 9,000 feet. Rock outcrop makes up 15 to 20 percent of this unit. The exposed bedrock consists of tuff, rhyolite, andesite and breccia. The shallow soils present have an effective rooting depth limited by depth to bedrock. Available water capacity is low. Surface runoff is rapid and erosion hazard is moderate. The shallow, well- drained, very stony Tolman soil makes up 55 to 70 percent of this unit. It formed in thin rhyolitic material and is ten to 20 inches thick over bedrock. Typically, the surface layer is grayish brown, very cobbly clay loam about six inches thick. The substratum is yellowish brown, extremely stony, light clay loam about three inches thick directly overlying hard fractured rhyolitic tuff bedrock at ten to 20 inches depths. Permeability is moderate. Effective rooting depth ranges from ten to 20 inches. Available water capacity is very low. Surface runoff is rapid and erosion hazard is severe. BUSHVALLEY - TELLURA COMPLEX These gentle to steep (nine to 65 percent) slope soils occur on mountain ridges and side slopes at elevations of 8,600 to 10,000 feet. The Bushvalley soils make up about 45 percent of the mapping unit, the Tellura soils make up about 40 percent, and about 15 percent is rock outcrop and soils that are moderately deep over bedrock. The Bushvalley is a shallow, well- drained, cobbly soil, formed in colluvium from volcanic rocks. Typically, the surface layer is dark brown cobbly loam about four inches thick. The subsoil layer is brown, extremely cobbly, clay loam about nine inches thick. Hard bedrock is below 13 inches. Permeability is moderate. Effective rooting depth is ten to 20 inches. Available waterholding capacity is low. Surface runoff is medium to rapid and erosion hazard is moderate. The Tellura soil is deep, well - drained, very cobbly soil formed in alluvium and slopewash materials from igneous rocks. Typically, the surface is dark gray, very cobbly loam about 13 inches thick. The subsoil layer is brown, very cobbly, heavy clay loam about 24 inches thick. The substratum is very pale brown extremely cobbly clay loam extending to 48 inches or more. Permeability is moderately low. Effective rooting depth is 48 inches or more. Available water holding capacity is high. Surface runoff is medium to rapid, and erosion hazard is moderate.