2012-03-07_PERMIT FILE - C2010088 (16)

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3.1 Map Unit RW: Reed Wash Typic Torrifluvents, 0 to 2% slopes Reed Wash is an ephemeral drainage that bisects the project area from northeast to southwest and soon joins the Colorado River. Within the project area, Reed Wash is incised about twenty feet below the adjacent alluvial plain, and will not be disturbed by project activities. Reed Wash is composed of an active drainage channel as well as an adjacent drainageway bottorrmland that includes apparent wetlands in small areas. Reed Wash was delineated in detail on the base map but soils were not described nor sampled. Typical soils include undifferentiated Typic Torrifluvents, which are well drained to poorly drained, variable- texture drainage soils with evident stratification. Because Reed Wash is not projected to be disturbed by project activities, neither a soil suitability evaluation nor a proposed salvage depth recommendation was developed. 3.2 Map Unit DL: Disturbed Land A large portion of the eastern and southeastern part of the project area is composed of previously disturbed and subsequently constructed "land farms" associated with land - applied waste products from the former, now closed, Gary Energy - Westem Slope Refining Company. All of these rectangular "land farm" fields are considered Disturbed Land (Map Unit DL) and are accurately delineated on the project soils map but were not described nor sampled as part of the baseline soil survey. They have been recently sampled as part of another project task. There is no suitable soil available for salvage from Disturbed Land (Map Unit DL). 3.3 Map Unit Bi: Billings loam to silty clay loam, 0 to 4% slopes Billings loam to silty clay loam (Map Unit Bi) is a deep, well drained, "fine- silty" soil mapped on the gently sloping alluvial plain, toeslopes, and minor, non4ncised narrow drainageways in the western part of the project area. Billings is developing in strongly saline and highly alkaline slopewash and drainage alluvium most likely from Mancos Shale badlands to the north. Map Unit Bi is dominated by "greasewood" vegetation. Small inclusions of Billings silty clay loam are located within Reed Wash. The Billings soil on the project area is similar to Billings (Map Unit Bs, Billings silty clay loam, 0 to 3% slopes) as mapped by NRCS on nearby areas in the Mesa County Area Soil Survey (Spears and Kleven, 1978). Billings loam to silty clay loam was fully described and sampled at three representative sites in the project area, TLO-1, TLO-2, and TLO-3. In a typical profile, Billings has a brown loam to silty clay loam "AC" horizon surface layer about 6 inches thick. The upper "C horizon substratum is a light yellowish brown loam to clay loam to a depth of about 46 inches. The lower "C" horizon substratum is a light brownish gray, moderately saline and moderately sodic, loam to silt loam to a depth of 72 inches or more. Billings loam has high available water holding capacity and slow permeability. The effective rooting depth 5 Exhibit 7 — 2010 Train Loadout Soil Survey