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The Universal Soil Loss Equation is: <br /> <br />A = RKLSCP <br />where A = soil loss (tons per acre) <br />R = the rainfall erosivity index <br />K = the soil erodibility index <br />L = the hillslope-length factor <br />S = the hillslope-gradient factor <br />C =the cropping-management factor <br />P = the erosion-control practice factor. <br />The R value is 40. <br />The K value is 0.25. This value is determined using a nomograph. The <br />nomograph is a series of graphs which takes into account the percent <br />silt, percent sand, percent organic matter, soil structure, and per- <br />meability of the affected soil. The characteristics of the affected <br />• soil were obtained using the description of soils listed for the <br />refuse pile area. <br />For a 45% slope and 97 foot slope length, the LS value is 15.3 (Haan, <br />1979). The LS value is a combination factor of slope and length. <br />The C value is 0.4 (Haan, 1979). The C value is based on 1.5 <br />tons/acre of mulch which is netted down. <br />The 60 percent ground cover is based on estimated herbaceous cover and <br />ground litter. Two growing seasons after seeding a 30 percent canopy <br />cover can be expected. The 30 percent ground litter will be from the <br />remaining mulch and dead vegetation. The ground litter will accumu- <br />late and not get washed away because of the lower slope and short <br />slope length. <br />CJ <br />4-51 <br />