2004-05-19_REVISION - M1979205 (2)

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Exhibit I -Soils Information The affected area ties at an elevation ofabout 5,330 feet and has slopes ranging from nearly level to a few percent. The soils are developed in alluvium and are generally deep and 4oamy to sandy- textured. The area was mapped by the USDA Soil Conservation Service (SCS) in 1985. Descriptions of soil units given below are based on an adaptation of the available SCS data. A soils map showing the general delineation of the soils present in the permit area follow this section. The Wann soil type is present is most of the disturbed area associated with the Phase I mining area. Kim loam is present in the Phase II mining area. The Torrifluvents soil type is located along the southern boundary of the permit area and in the Phase III mining area. 40 -Kim loam This deep, well drained, gently to sloping soil is on alluvaial fans and benches. Elevation ranges from 5,000 to 6,000 feet. The soils are on slopes ofabout 3 to 6 percent. This soil is formed in alluvium derived from shale and sandstone. Typically the surface layer is a yellowish brown or light yellowish brown loam about 17 inches thick. The underlying material is light brownish gray loam to a depth ofabout 60 inches. In places the underlying material is stratified with fine sandy loam. Permeability is moderate, and available water capacity is high. The surface runoff is slow and the erosion potential is moderate. A representative profile of the Kim loam is included herein. Included with this soil in mapping are small areas of Arvada and Olney soils that have slopes of 3 to 6 percent. These areas make up 5 to 15 percent of the map unit. This soil is used mainly for crops, hay, and pasture. Alfalfa, small grains, and grass or grass- legume mixtures are grown. This soil is irrigated by flooding or furrows. Sprinklers are also suitable. Drop stnrctures in ditches control water and prevent excessive ditch erosion. The native vetetation on this soil is mainly wheat grasses, needleandthread, and sagebrush. 65-Torrifluvents This broadly defined unit consists of deep, well drained to somewhat poorly drained, nearly level soils on flood plains adjacent to the Colorado and Roaring Fork Rivers and their major tributaries. Slope is 0 to 6 percent. The soils formed in alluvium.These soils 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. The water table fluctuates between depths of 2 and 4 feet and in some years is near the surface during spring runoff from snowmelt. These soils are subject to brief, occasional flooding late in spring and early in summer. Page I - l