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Revised 1/11/2016 <br />Page 3 <br />Section 3.03.1 <br />using the same method but by using the data as collected from the Loadout reclaimed area in 2013 <br />and 2014. The C factor for the different vegetation types and cover were determined from Table <br />8B.2, C factors for Permanent Pasture, Rangeland, Idle land, and Grazed Woodlands, found in Design <br />Hydrology and Sedimentology for Small Catchments, Barfield Warner and Hayes, 1994. The values utilized are <br />shown on Table 1. <br />Table 1 <br />C Factors <br />Loadout % Canopy and <br />Type % <br />C <br />Height <br />Ground <br />Factor <br />Cover <br />Non -mined reference area 25% <br />G 66.83% <br />.0292 <br />Reclaimed 25% <br />G 69.5% <br />.0285 <br />Support Practice Factor (P) <br />The P factor represents the ratio of soil loss from any conservation practice to that with upslope and <br />downslope tillage. It is used to evaluate the effects of contour tillage, strip -cropping, terracing, subsurface <br />drainage, and dryland farm surface roughening. While a cover crop and seeding practices on the reclaimed <br />area may have roughened the soil initially in the revegetation liability period, there is no support for any <br />remaining effects of these conservation practices as compared to the non -mined reference area. For the <br />reclaimed and non -mined conditions a P factor of 1.0 was used. <br />RF.SiILTS <br />The above input parameters were substituted into the RUSLE equation for both the reclaimed and non - <br />mined condition. As shown below in Table 2, sediment yield for the reclaimed condition is slightly less <br />than the non -mined condition for the Southfield Loadout. <br />Non -mined condition <br />A=RKLSCP <br />A = (24.7) (.32) (2.05) (.0292) (1.0) <br />A = .473 <br />Reclaimed condition <br />A=RKLSCP <br />A = (24.7)(.32)(2.05)(.0285)(1.0) <br />A = .461 <br />The reclaimed condition produces less sediment than the non -mined condition. A summary of the <br />results are shown on Table 2. <br />Table 2 <br />Loadout Annual Sediment Yield <br />tons/acre/year <br />Reclaimed Condition .461 <br />Non -mined Condition .473 <br />4.0 REFERENCES <br />Barfield, B.J., Haan, C.T., J.C, Hayes, J.C., 1994, Design Hydrology and Sedimentology for Small <br />Catchments <br />