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Sediment Demonstration — Mine Site - revised 1/13/2016 w/ addendum Page 6 Section 3.03.1 However, when calculating the LS factor using the footprint area and the actual slopes from the immediate adjacent area that surrounds the RDA, the modeling output changes significantly. Demonstration #2 uses information from the actual pre -mine topography of the RDA footprint as well as from adjacent, non -mined lands surrounding the RDA area. Demo #2 Adjacent, non -mined condition A=RKLSCP A = (24-7)(.32)(3.34)(.02136)(1.0) A=.564 Demo #2 Reclaimed RDA condition A=RKLSCP A = (24.7)(.32)(4.56)(.011)(1.0) A =.396 In this scenario, the reclaimed RDA condition produces less sediment than the non -mined, adjacent condition. A summary of the results are shown on Table 4. Table 4 RDA Annual Sediment Yield tons/acre/year Adjacent, non -mined Condition .564 Reclaimed RDA Condition .396 Averaging all the values from the three sediment demonstrations conducted by EFCI is likely the most accurate over the long term. Predictions from RUSLE represent soil loss averaged over many storms and years. It also represents averages over a total field or disturbed area. [Barfield, B.J., Haan, C.T., Hayes, J.C., 1994]. Table 5 below shows the results from averaging the three methodologies for the sediment modeling efforts from Table 2, Table 3, and Table 4. Table 5 RDA and mine site Annual Sediment Yield tons/acre/year Pre -mining avera e , three demonstrations .424 Post -mine average, three demonstrations .356 The post -mining average sediment yield is less that the pre -mining average sediment yield. Therefore, the requirements of Rule 3.03.1 (3) (b) have been met for the Southfield Mine. 4.0 REFERENCES Barfield, B.J., Haan, C.T., Hayes, J.C., 1994, Design Hydrology and Sedimentology for Small Catchments