2009-08-17_PERMIT FILE - C1981028A (2)

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• 2.04.3 SITE DESCRIPTION AND LAND USE INFORMATION The area proposed for mining is located on level to gently rolling topography consisting of fine sand, which iswind-deposited material overlying residual shale. The sand varies in depth from about 5 feet to 20 feet, is excessively to moderately permeable, and is highly susceptible to wind erosion. For these reasons, the land capability is classified as VIe for dryland farming and IVe for imgated farming. See Appendix L-I, Pages 5-8. The proposed non-imgated site is classified as Rangeland by the U.S. Department of Agriculture, Soil Conservation Service, as shown on the following General Soil Map, Weld County, Colorado, and the land is utilized for gazing of livestock. This Deep Sand Range Site is a kind of rangeland that cannot support a variety of uses under existing technologies and local resources. All attempts at dryland farming on the area have been abandoned, and the damage caused by those attempts will remain evident for many decades. Otherwise, the land is moderately to well stabilized by asandsage-prairie sandreed plant association that is used primarily for grazing by cattle in summer months. The Weld County Conservation District office advises that the site is excluded from the Central Colorado Water Conservancy District because it lacks potential for water development. Reliable information on land productivity is not available. The Soil Conservation Service • lists median-year herbage production at 1,800 pounds per acre air dry for the Deep Sand Range Site with an average annual precipitation of 15 inches. Fort Lupton, which has an average annual precipitation of 12.5 inches, provides our best estimate of precipitation at the area proposed for mining. With that amount of precipitation, we would expect an average production of 800 to 1,000 pounds per acre. We have yield data from experimental plots seeded in 1978 and established with irrigation. Yields in 1979 varied from 1,344 kg/ha oven dry on plots mulched with straw to 2,244 kg/ha oven dry on plots mulched with manure. However, those yields were inflated by unusually high growing-season precipitation (12.23 inches, which is 185% as much as the long-term average at Fort Lupton), carry-over fertility, and the high state of plant vigor that characterizes new stands. If we assume that productivity on the plots mulched with straw were least inflated by those factors, and divide the yield of 1,344 by 1.85, we obtain an estimate of "normal" productivity at 726 kg/ha in the absence of sandsage. In the same year, the Valent Sand Reference Area produce 652 kg/ha oven dry, which may be divided by 1.85 to estimate a "normal" productivity of 352 kg/ha in the presence of sandsage. Income loss from forage taken out of production is estimated to be 90¢ an acre per year. This figure is based on 1980 fees per Animal Unit Month charged by the Pawnee Grazing Association on U.S. Forest Service land in Weld County and, in discussions with the U.S. Forest Service and the Weld County Conservation Office, total acreage needed for good . management practices on land similar to the Mine site. 34