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Mr. Donald A. Crane Mr. Dean Massey July 16, 1980 Page 4 ~~ 7,200 feet and 8,400 feet in elevation. Aspen forest is the dominant vegetation community in the area with some big sagebrush and mountain shrub areas. Soils The study area, as mapped by the SCS in 1978, was reported to contain two major mapping units: Winevada-Splitro (X8D, X8F) and Skyway (70D, 70F). Originally, in soils mapping conducted by the SCS in 1975, all of the aspen areas in Eckman Park were mapped as X8, with D or F slope groupings. This complex consisted of: 1) Winevada series, a member of the fine-loamy family of Pachic Cryoborolls which is moderately deep over hard sandstone (at 20 - 90 inches); 2) Splitro series, a member of the coarse-loamy family of Lithic Cryoborolls which is shallow over fractured hard sandstone (at less than 20 inches). In 1978 the Soil Conservation Service changed some of the areas that had been .mapped X8 and delineated them as 70D and 70F (Skyway). Basically, they continued to call all previously mapped soils in the eastern portion of Eckman Park that had been disturbed, as falling within the Winevada-Splitro complex (X8), while all soils to the west of mining were changed from the XS unit to the new Skyway (70) unit. As reported by the SCS soils mapping crew, the 70 unit in Eckman Park was the first reported site of that soil type found in northwest Colorado. Since the 70 unit in Eckman Park was set up as the type location of Skyway loam in northwest Colorado, information on profile descriptions, mapping unit descriptions and typical pedon descriptions was unavailable and was not submitted by EFC (as pointed out by OSM in their technical assessment of Sections 816.21-816.25). Skyway is a member of the coarse-loamy family of Pachic Cryoborolls and is moderately deep over hard sandstone (at 20 - 40 inches). The difference between Skyway and Winevada-Splitro is as follows: 1) Winevada soils have more than 18 percent clay in the control sec- tion; 2) Splitro soils have bedroc}: below 20 inches in depth; 3) Sky- way has less than 18 percent clay in the control section and bedrock at a depth of 20 - 40 inches. Upon further investigation of these mapping units, it was deter- mined by the SCS that all areas.would_again be delineated ~s XB_, with D or F slope groupings. The small areas found to be coarse- loamy in the control section were not of large enough areal extent to be separated out, and, consequently, the 70D an_d F mapping unit areas were deleted. Energy Fuels was not informed of this change (deletion of 70D and 70F) in soil mapping unit delineations until the summer of 1980.