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The value of each of these factors used in the determination of soil loss <br />were: <br />R=30 <br />K = 0.22 <br />C=.12 <br />P = 0.9 <br />LS = 29.59 (variable depending upon the percent slope and length of <br />slope for the watershed). <br />Determination of the sediment yield from the soil loss rates requires <br />application of the delivery ratio. This reflects the amount of sediment <br />delivered to a particular location versus the amount of soil loss. Based <br />upon a review of the available data for existing Pond 004 which is in a <br />drainage similar to Pond 008, actual sediment yields on an annual basis <br />have been measured at 0.38 ac-ft/yr. Based on this information, a <br />sediment delivery ratio of 60 percent was used to calculate sediment <br />• storage. <br />A sediment density of 80 pounds per cubic foot was applied to the sediment <br />yield to obtain the sediment volume used to size Sediment Pond 008. <br />The procedure for estimating soil loss volume is shown below for Sediment <br />Pond 008. <br />The disturbed area was calculated to be 247.54 acres (the disturbed area <br />due to mining) and was assigned the following values: R = 30, K = 0.22, <br />LS = 29.59, C = 0.12, and P = 0.9. The soil loss in tons per acre per <br />year was calculated as follows: <br />A = (30)(0.22)(29.59)(0.12)(0.9) = 21 tons/acre/year <br />According to the delivery ratios previously discussed, it is estimated <br />. that only 60 percent of this erosion quantity will reach the sediment <br />pond. The remaining sediment would be deposited in route. Therefore, for <br />7-6e-8 <br />