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For slopes < 9% <br />LS = (L I72.6)' x (10.8 x sin(S) + 0.03) <br />For slopes > 9% <br />LS = (L/72.6)' x (16.8 x sin(S) + 0.5) <br />Where: L = Slope length <br />S = Slope angle <br />in = 0.3 for slopes< 3% <br />0.4 for slopes = 4% <br />0.5 for slopes > 5% and < 10% <br />0.6 for slopes> 10% <br />The slope length and slope angles for the pre and post mine conditions were determined from the <br />Map 13 and Map 29 respectively. The LS factor for each slope length and angle were determined <br />and then averaged. The LS calculations can be found in Attachment 1, Calculation Spreadsheets. <br />2.4 Cover Management Factor (C) <br />The cover management factor represents the effects of vegetation, management, and erosion - control <br />practices on soil loss. The C factors for pre and post mine condition for the area was determine using <br />information from the Vegetation study done by IME in 2007 and 2010. The C factor of the <br />different vegetation types and cover were determined from Table 5.A.3 found in Applied Hydrology <br />and Sedimentology for Disturbed Areas, Barfield Warner and Haan. The values utilized are shown on <br />Table 1. <br />Table 1 <br />C Factors <br />Area <br />% Canopy <br />and Height <br />Type <br />% Ground <br />Cover <br />C <br />Factor <br />Loadout Pre Mine <br />0% <br />G <br />39% <br />0.10 <br />Loadout Post Mine <br />0% <br />G <br />51% <br />0.07 <br />2.5 Support Practice Factor (P) <br />The P factor represents practices designed to control erosion. For existing condition a P factor of 0.8 was <br />used to account for the rough soil conditions from disking along contour and seed drilling. For pre mine <br />conditions a P factor of 1.0 was used. <br />