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calculations. The variables employed in the RUSLE equation and their definitions are presented in the <br /> table III below. <br /> Table G1: SL4 Williams Fork Bond Release RUSLE Variables and Calculations <br /> Bond Length Slope <br /> Release Acres R K of 0 Elev Gradient LS C P A A(Weighted <br /> Polygon Segment AVG) <br /> Utah 105 16 0.28 845 150 18 4.22 0.001 0.9 0.0170 0.00654 <br /> Tract A <br /> Utah 105.3 16 0.28 1000 150 15 3.38 0.0009 0.9 0.0123 0.00473 <br /> Tract B <br /> WF Strip 62.7 16 0.28 525 75 14 2.69 0.003 0.9 0.0325 0.00747 <br /> Pit <br /> AVG Tons/Acre/Year 0.01875 <br /> Table G2: SL4 Williams Fork Bond Release RUSLE Variables and Calculations for Reference Area <br /> Length <br /> Reference Area R K of Slope LS C P A <br /> Elev Gradient <br /> Segment <br /> Utah Tract Ref Area A 16 0.28 455 50 11 1.84 0.004 0.9 0.0297 <br /> WF Strip Pit Ref Area B 16 0.37 915 100 11 2.08 0.002 0.9 0.0222 <br /> WF Strip Pit Ref Area C i 16 i 0.37 1000 i 75 8 i 1.31 0.003 0.9 0.0209 <br /> *Note: Tables G1 and G2 derive from MCM's Attachment G,as submitted with the bond release request. <br /> Table III. R USLE Variables and their Definitions <br /> Variable Definition <br /> R Climatic erosivity factor due to precipitation <br /> K Soil erodibility under a standard condition <br /> LS Slope length and steepness factor <br /> C Cover management/land use <br /> P Support practices factor <br /> R Factor.Erosivity of Rainfall and Runoff <br /> The R Factor quantifies the effect of raindrop impacts and reflects the amount and rate of runoff <br /> associated with annual precipitation. The value used for this factor was obtained from the EPA Rainfall <br /> Erosivity Factor Calculator. The calculator accounts for the mine location and disturbance dates to relate <br /> back to historic rainfall data. <br /> K Factor, Soil Erodibility <br /> The K Factor indicates the relative susceptibility of surface soil to water erosion. Values can vary from 0.0 <br /> to .2. The higher value indicates higher erosion susceptibility. In Tab 09,Addendum 5 of the Williams <br /> Fork permit the baseline Soil Study conducted for the mining permit,the K factor, soil erodibility was <br /> determined to be anywhere from 0.19 to 0.36. This demonstration utilized values from 0.28 to 0.37. <br /> Permit Number C1981044 Page 17 of 25 <br />