2014-05-07_PERMIT FILE - C1996083 (2)

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• Volume III, Tab 7 Sandstone outcrop. This soil is forming in place from the fine-textured, clayey residuum of the Mancos Shale bedrock. The areas of Map Unit 4 delineated during the original 1995 soil survey are generally at the same elevation as in the Gob Pile study area, perhaps indicating the Mancos Shale stratum lies across the landscape in the same relative position, with portions of it nearly outcropping and other portions now under a mantle of slopwash colluvial material from upslope sandstone sources. The Mancos clay loam soil is moderately deep (20 to 40" to bedrock) to deep (40 to 60" or more to bedrock) and well drained. It is nonsaline to slightly saline, and nonsodic to slightly sodic. Although Mancos clay loam has heavy clay texture (profile weight average clay = 46.8%), the soil is otherwise "suitable" and could be salvaged to 30 inches if necessary. The soil has slow to very slow permeability and moderate available water holding capacity. The effective rooting depth is 30 inches or more. Runoff is medium and the water erosion hazard is moderate to severe. In a typical profile, Mancos clay loam has a brown surface and upper subsoil layer with clay loam texture about 5 inches thick. The "B" horizon subsoil layer is a dark brown clay about 11 inches thick, to a depth of about 16 inches. The underlying upper "C" horizon substratum is a grayish brown clay about 14 inches thick, from 16 to 30 inches in depth. The lower "C" horizon substratum layer is a pale brown clay to a depth of about 46 inches. Rock fragment content of the profile is less than 5 percent small shale chips. Mancos clay loam Typical Soil Sample "S3" Site and Profile Description: 8% slope; south aspect; mixed grasses including cheat grass, scattered sagebrush, a few scattered Juniper trees vegetation; slightly sloping upland bench position; stable surface; no erosion in vicinity of sample site; slow to very slow permeability. A & Bw1 horizon - 0 to 5 inches; brown (10YR 5/3) clay loam with less than 5% small shale chips, dark brown (10YR 4/3) moist; moderate medium granular structure over moderate fine subangular blocky structure; slightly hard, friable, sticky and plastic consistence; common fine and very fine, and few medium and coarse roots; noneffervescent; from lab data: pH=5.8 (moderately acid), EC=0.5 (nonsaline), SAR=0.5 (nonsodic), OM=5.9%; gradual smooth boundary. Bw2 horizon - 5 to 16 inches; dark brown (10YR 4/3) clay with less than 5% small shale chips, dark brown (10YR 3/3) moist; moist; moderate medium subangular blocky structure; hard, firm, sticky and plastic consistence; common fine and very fine, and few medium and coarse roots; noneffervescent; from lab data: pH=5.9 (moderately acid), EC=0.3 (nonsaline), SAR=1.2 (nonsodic), OM=3.2; gradual wavy boundary. C1 horizon - 16 to 30 inches; grayish brown (10YR 5/2) clay with less than 5% small 9 Exhibit 7 - 2007 Soil Survey Report