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