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Sediment Demonstration — Mine Site - revised 1/13/2016 w/ addendum Page 5 <br />Section 3.03.1 <br />slope information from the reclaimed RDA for the post -mining condition. Average cover values <br />from 2013 and 2014 were used from the RDA reference area sampling and from the reclaimed RDA <br />sampling respectively. <br />LS factors for the two additional demonstrations are shown below. <br />Demo #1 RDA footprint only <br />Len (ft) <br />Slope (%o) <br />LS Factor <br />700 <br />6% <br />2.10 <br />Demo #1 Post weight RDA <br />Length ft <br />Sloe %o <br />LS Factors ave. <br />500/240 <br />3.4/24.4 <br />4.56 <br />Demo #2 Adjacent areas <br />Length (ft) <br />Slope (%) <br />LS Factors ave. <br />700/500/200/300 <br />6/6/25/8.3 <br />3.34 <br />Demo #2 Post weight RDA <br />Length ft <br />Sloe % <br />LS Factors ave. <br />500/240 <br />3.4/24.4 <br />4.56 <br />C factor values specific to the RDA were used. The C factor for the RDA reference area is 0.02136. <br />The C factor for the RDA reclaimed area is 0.011. Factors for R, K, and P remain unchanged for <br />reasons previously discussed. <br />Demo #1 Pre -mine RDA footprint <br />A=RKLSCP <br />A = (24.7) (.32) (2.10) (.02136) (1.0) <br />A = .355 <br />Demo #1 Reclaimed RDA condition <br />A=RKLSCP <br />A = (24.7)(.32)(4.56)(.011)(1.0) <br />A=.396 <br />In this scenario, the results show that the reclaimed RDA individually produces more sediment than <br />the exact same area in the pre -mine condition. To overcome the influence of the increased LS factor <br />that result from construction of the approved RDA, the cover values on the reclaimed RDA would <br />need to be close to 85% cover for the output values to equalize. A summary of the results is shown <br />in Table 3 below. <br />Table 3 <br />RDA Annual Sediment Yield <br />tons/acre/year <br />Pre -mine RDA footprint .355 <br />Reclaimed RDA Condition .396 <br />