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Total Perennial Cover 58.2% <br />Litter 16.3% <br />Perennial Cover + Litter 74.5% <br />Canopy (Trees and Shrubs) 0.8% <br />The Universal Soil Loss Equation will be used to calculate the soil loss from the <br />reclaimed mine site and the baseline conditions to determine if untreated drainage from <br />the reclaimed mine site is contributing suspended solids in excess of pre-mining levels. <br />The following sediment volume calculation is prepared in accordance with U. S. <br />Department of Agriculture, Technical Notes, Agronomy Note #50, dated January, 1977. <br />USING THE UNIVERSAL SOIL LOSS EQUATION <br />R (rainfall) factors are assigned by geographical regions based on weather data <br />furnished by the U.S. Weather Service. R values are based on rainfall amount, time <br />• and intensity. In the mountains, R values were computed primarily for valley areas and <br />have been increased to account for run-off from snow melt. The R factor used for this <br />calculation is derived from an iso-erodent map and is the same for both the reclaimed <br />slope and the original slope. <br />K (soil erodibility) factors are assigned to each soil series and they are used to predict <br />the erodibility of a soil and its tolerance to erosion in relation to specific kinds of land <br />use and treatment. Soils having the highest K value are the most erodible. The K value <br />used for this calculation is picked from the U.S. Department of Agriculture Soil Survey, <br />Paonia Area, and is based on the soils classification; Absarokee. The K factor of 0.37 <br />is the same for both the reclaimed slope and the original slope. <br />LS (length and percent slope) factors account for the length and percent slope. These <br />factors are taken from Figure 4. Length of slope begins at the top of the micro <br />watershed. This is usually at the top of a hill, ridge, terrace or diversion. The length of <br />slope is considered to end for a given field atone of the following places: (1) the point <br />where the slope decreases to the extent that deposition occurs, (2) the point where <br />runoff enters swell-defined channel, gully, terrace or diversion, or (3) where water <br />. leaves the field. The LS for the reclaimed slope was measured from the crest of the <br />portal bench to the first bench where the length is about 255-feet and the slope is about <br />Appendix C <br />-r~--r~ <br />,g PpRov~fl <br />io~7~o8 <br />2 of 4 <br />9/08 <br />