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The soil erodibility factor "K", is difficult to determine accurately, since all soil was <br />imported and in the process of rehandling has been altered. A reasonable "K" factor for <br />soils in this area has been assumed, based on SCS mapping and analysis of the regional <br />soils. The soil is considered a silty clay loam with a "K" of 0.37. <br />Leneth Slope Factor "LS" <br />The effects of topography on soil erosion are determined by the dimensionless "L" and <br />"S" factors, which account for both rill and interrill erosion. These factors have been <br />considerably revised since the initial Universal Soil Loss Equation. The new RUSLE <br />computer database for the combined "LS" factor is based on the soil's ratio of rill to <br />interrill erosion. For most western rangeland soils, the equations for low rill to interrill <br />ratio are used. Table 1 (from Predicting Soil Erosion by Water: A Guide to <br />Conservation Planning With the Revised Universal Soil Loss Equation - US <br />Department of Agriculture 1997) shows a chart based on these equations. <br />The reclaimed site basically consists of three segments: <br />1) a backfilled slope of approximately 2H:1V for a distance of approximately 35' <br />followed by 2) a bench which gradually drops approximately 18' in 380' to the County <br />Road level, followed by 3) a flat area along the County Road leading to the sediment <br />pond which is 520' long and drops 10' over this distance. <br />From Table 1, it is seen that the "LS" factor for segments 1,2 and 3 are as follows: <br />Segment # LS Factor <br />1 4.4 <br />2 0.78 <br />3 0.34 <br />4 <br />