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Soils in the permit area generally exhibit significant profile development to depths of 24 to 36 <br />inches. Residual soils in the area have A horizons of four to six inches of dark brown sandy <br />loam or loam. These soils have a light brown, very sandy surface that is very gravelly (4mm to <br />20mm) instead of exhibiting the full range of gravels revealed at depth. <br />The soils over the area pictured have B-horizons of seven to ten inches thick of sandy loams, <br />sand or gravelly, sandy loam texture. <br />Parent materials are generally from quaternary glacial till and alluvium; most common appear <br />to be gneiss. The weathering and glacial transport of this material has led to the development <br />of the sandy soils and cobbled profiles encountered across the entire permitted operation. <br />Adjacent tailings piles and disturbances that probably go back to turn of the 19th Century (1908 <br />to 1940's) appear upstream and demonstrate very little to `none' of soils development or re- <br />vegetation. A few patches of volunteer willow and other shrubs and forbs can be found in all <br />areas. This vegetation is occurring in soils which have been stripped to below the C horizon <br />and indicate that nutrient material exists in clay stringers and other remnants of the exposed <br />deeper horizons which is capable of nurturing plant growth. <br />SITE SPECIFIC SOILS <br />Three basic soil pedons occur on site. The first of these (mapped as UF) is found on flat to very <br />gently sloping, open grassy areas. The second pedon (mapped as MS) is similar to unit OF but <br />has been disturbed in previous mining operations and the third unit (mapped unit GO) is <br />primarily glacial outwash which has various sorting according to streambed actions over past <br />eons. <br />Map Unit OF <br />A typical profile of this unit is comparable to Venable type mountain soil: Deep, poorly <br />drained valley floor soils of fine, loamy alluvium / Slope of 0 to 9 percent and comprised of <br />igneous and metamorphic rocks. These soils are fine loamy, mixed Cumulic Cryaquolls. The <br />elevation averages 9850 ft to 10,000 ft with average annual precipitation of 17 to 25 inches of <br />water over a free season of 55 to 75 days at. temperatures averaging 41 to 43 degrees F. <br />Map Unit GO <br />Soils of this unit appear to occur along the east - west trending moraine of a past glacier. The <br />large plain was sculpted and cut by the Platte River and reveals very gravelly soil with cobbles <br />or cobbled loam and cobbled sandy-silty loam. These of course are very well drained with <br />rapid permeability. These soils would have a high erosion hazard potential if left exposed to <br />wind and water. <br />Map Unit MS <br />These delineations are the result of past mining operations. Areas where this unit can be <br />mapped include flats cut by front-end loader and nearby dredge boat tailpiece clean out piles. <br />Volunteer vegetation occurs in varying degrees and supports a fair `prognosis' for reclamation <br />success based on nutrient availability, however a high gravel or cobble content seems to be the