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levels as required in Rule 4.15.1 (2) (b) and suspended solids delivered to streamflow outside the <br /> permit area will not exceed pre-mining levels as required under Rule 3.03.1 (3) (b). The <br /> methodology used is the Revised Universal Soil Loss Equation (RUSLE)using site-specific soil and <br /> vegetation data along with slope measurements comparing the Bond Release Area and associated <br /> reference areas. RUSLE was used to calculate predicted annual sediment erosion in tons/acre/year <br /> based on the equation: <br /> A (soil loss in tons/acre/year) =R•K•L•S•C•P <br /> Where: A=predicted erosion in tons/acre/year <br /> R=erosivity index of local rainfall <br /> K = soil erodibility actor <br /> LS = length/slope factor <br /> C =vegetative cover factor <br /> P =management practice factor <br /> Dryland Pasture— Sedimentology Results <br /> The table below presents the predicted soil loss in tons/acre/year on a representative slope from the <br /> Dryland Pasture Phase II Bond Release Area for pre-mining and post-mining evaluations. The <br /> premining representative slope exhibited 0.165 tons/acre/year of predicted soil loss. In comparison, <br /> the post-mining representative slope exhibited 0.102 tons/acre/year of predicted soil loss. <br /> A (soil loss in tons/acre/year) for Dryland Pasture <br /> Parameter Pre- Post- <br /> Mining Mining <br /> - Factor <br /> - Factor <br /> LS - Factor <br /> - Factor <br /> - Factor <br /> A (soil loss in tons 0.165 0.102 <br /> /acre/ ear <br /> Phase II Bond Release Area post-mining evaluation exhibits less predicted erosion than the pre- <br /> mining evaluation with 0.165 tons/acre/year versus 0.102 tons/acre/year. <br /> C1981008 SL25 Page 11 of 14 <br />