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The Parachute Site is situated in the Parachute Creek valley and contains the following soil units: Nihill channery sandy loam, Torrifluvents, Olney loam, Heldt clay loam, and Arvada loam. Nihill channery sandy loam is described above. Nihill soils comprise 61 acres (20 percent) of the Parachute Site, of which approximately 33 acres would be disturbed for construction of project facilities. Torrifluvents comprise 46 acres (15 percent) of the Parachute Site. This unit consists of deep, well-drained to somewhat poorly drained, nearly level soils on floodplains. They are stratified and vary widely in texture and depth. The surface layer ranges from loamy sand and fine sandy loam to silty loam and clay loam. The underlying layers are generally sandy loam or loam stratified with sand, gravel, and cobbles. In some areas, gravel and cobbles are on or near the surface. These soils have a seasonal high water table and are subject to brief, occasional flooding in late spring and early summer. Only approximately 1 acre of Torrifluvents would be disturbed for construction of project facilities at the Parachute Site. Olney loamy are on nearly level alluvial fans and sides of valleys. They are deep, well-drained soils with moderate permeability and moderate available water capacity (SCS 1985.) Slopes are 1 to 6 percent. Water erosion hazard is slight to moderate, and wind erosion hazard is slight to very slight. Typical topsoils are 12 inches deep, with an additio:i 21 inches of subsoil. There are no soil limitations relative to soil salvage and reclamation. These soils may be a good source of reclamation material. These soil units comprise 47 acres (16 percent) of the Parachute Site, of which approximately 7 acres would be disturbed for construction of project facilities. Arvada loams are also located on benches, terraces, and outwash fans. They are deep, well-drained soils with very slow permeability and moderate to high available water capacity. Slopes are 1 to 20 percent. Water erosion hazard is moderate to severe, and wind erosion hazard is moderate. Typical topsoils are 3 inches deep, with an additional 14 inches of subsoil. Topsoils may be strongly alkaline or very strongly alkaline, and this and erosion potential are the main limiting factors for this soil type (SCS 1985). Arvada soils comprise 130 acres (43 percent) of the Parachute Site, of which approximately 16 acres would be disturbed for construction of project facilities. Heldt clay loamy are located on gently sloping alluvial fans and sides of valleys. They are deep, well-drained soils with slow permeability and moderate available water capacity. Slopes are 1 to 3 percent. Water erosion and wind erosion hazard are slight. Excessive clay is the only limiting factor for this soil type (SCS 1985). Typical topsoils are about 8 inches thick, with an additional 13 inches of subsoil. This soil unit comprises 20 acres (6 percent) of the Parachute Site. I-7