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Heldt soils are on alluvial fans. They aze deep and well drained. The surface layer and subsoil aze clay loam and the substratum is clay. Referring to the attached soils map the following observations are made Soils Map Unit 65: The Colorado River flows in a southwesterly direction defining the northern ' boundary of the proposed mine. The majority of soils following the river and extending south into the affected azea are classified as Totrifluvents, neazly level. This unit consists of deep, well drained to somewhat poorly drained, nearly level soils on the flood plain adjacent to the river. The slope is 0 to 6 percent. The soils formed in alluvium and 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 snow melt. These soils aze subject to brief, occasional flooding in late spring and early summer. The native vegetation is mainly cottonwood, willow, tamarisk and J water-tolerant grasses, sedges and rashes. The soils are suitable for wildlife habitat and some grazing. These soils are incapability subclass Vllw, nonirrigated Soils Map Unit 72: Beginning on the eastern boundary and following southwest to about the I midway portion of the map, the soils are considered to be Warn Sandy Loam ,Ito 3 percent slopes. This is deep, somewhat poorly drained, nearly level to gently sloping, low-lying soil. The soil formed in alluvium derived primarily from sandstone and shale. Typically, the upper I part of the surface layer is dark grayish brown sandy loam about 8 inches thick, and the lower part is dark grayish brown fine sandy loam about 4 inches thick. The upper part of the underlying material is mottled, light brownish gray fine sandy loam about 24 inches thick, and I the lower part is mottled light brownish gray course sandy foam to a depth of 60 inches. The soil exhibits moderately rapid permeability, and available water capacity is high. Effective rooting depth vanes with the level of the water table but is usually about 2 feet. Surface runoff is slow and the erosion hazard is moderate. Depth to the water table ranges from 2 to 3 feet depending on the amount of irrigation water supplied. Water ponds in spring. The native vegetation contains saltgrass, wheatgrass, sedges, rabbitbrush and alkali sacaton. The soil is used mainly for grazing, grass or legume hay and pasture. When the range is in poor condition undesirable weeds and annual plants abound. This soil is incapability subclasses IVw, irrigated and VI, nonirrigated. J Soils Map Unit 3: The southeast comer of the property consists of Arvada Loam, 1 to 6 percent slopes. This deep, well drained, sloping soil is on fans and high terraces. This soil formed in highly saline alluvium derived from sandstone and shale. Typically, the surface layer is strongly alkaline ,pale brown loam about 3 inches thick. The subsoil is brown silty clay loam about 14 ' inches thick. The substratum is light brown or brown silty clay loam to a depth of 60 inches. Permeability is very slow, and available water capacity is moderate. Effective rooting depth is