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EXHIBIT 25 <br />• SOIL LOS9 DETERMINATION - BEAR NO. 1 & NO. 2 MINES <br />RECLAIMED VERSUS NATURAL CONDITIONS <br />"tPhe`foliowing calculations are presented to determine if <br />untreated drainage from the reclaimed mine sites is <br />contributing additional suspended solids above natural <br />conditions. <br />Published data will be used to compare the reclaimed mine <br />sites to the natural conditions. The Soil Survey of Paonia <br />Area, Colorado, published by the Soil Conservation Service <br />in 1981 identifies soil types for specific areas. The <br />Bear No. 1 & No. 2 Mines are located in the Breece Loam <br />soil type. Erodiblity factors published for the Breece <br />Loam soil type includes a K-Factor of 0.20 and a T-Factor <br />of 5 tons per acre per year. <br />A calculation will be made to determine the estimated annual <br />soil loss from the No. 1 Mine and the No. 2 Mine. In order to <br />conclude that the reclaimed mines are not contributing addition <br />suspended solids above natural conditions the estimated <br />soil loss from the mines must be less that the published data <br />of 5 tons/acre/year. <br />The condition of the reclaimed mine <br />vegetation surveys performed during <br />• of the vegetation reports are as fo <br />Total Perennial Cover ~ <br />Litter ~ <br />Total Cover $ <br />sites is taken from the <br />1991 & 1992. The results <br />Llows: <br />1991 1992 <br />------------------ <br />------------------ <br />37.7 35.7 <br />25.6 29.6 <br />------------------ <br />------------------ <br />63.3 65.3 <br />The Umiversal'Soil Loss Equation will be used to <br />calculate the soil loss from the reclaimed mine sites. <br />If the calculated soil loss is less than the published <br />T-Factor of 5 tons per acre per year, then it is assumed <br />that the untreated drainage from the mine sites will not <br />contribute suspended solids above natural conditions. <br />The following sediment volume calculation is prepared in <br />accordance with U. S. Department of Agriculture, Technical <br />Notes, Agronomy Note #50, dated January, 1977. <br />A separate LS factor for the LISLE equation is calculated for <br />the Bear No. 1 Mine and the Bear No. 2 Mine. The slope <br />length for the No. 1 Mine and the No. 2 Mine is 100' and 270' <br />respectively. The slope of the mines is determined by using <br />the following equation for determining watershed slope: <br />S = .25*Z*(LC25+LC50+LC75)/DA <br /> <br />-8- <br />