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LS ( L )m * (10 sim 9 + 0.027) for S < 8b <br />72.6 <br />LS = ( L )m * (17.2 sin g-0.55) for 5 > Bb <br />72.6 <br />where 5 is the slope in percent, L is the representative slope length in feet, m is an <br />exponent dependent on slope (m = .3 for S < 3b; m = .4 for 5 = 4b; m = .B for Sb <S <10b; <br />and m = .6 for S> tOb), and 0 is the slope angle. <br />The C and P Factors. The C factor, the cover and management factor, is the ratio of soil <br />loss from an area with specified cover and management to that from an identical area in <br />tilled continuous fallow. The P factor, the support practice factor, is the ratio of soil <br />loss with a support practice like contouring, strip cropping, or terracing to that with <br />straight row farming up and down the slope. The C factor was determined based on the <br />vegetation description in Tab 10 and with the aid of the USDA-ARS revised USLE software <br />program for each cover type within the overall drainage area. The P factor is based on <br />current or future practice. Table 3 contains the typical C and P factors utilized for the <br />Seneca II-W Mine area. • <br />TABLE 3 <br />C and P Factors (Native/Reclaimed) <br />Seneca II-W Mine, Colorado <br />Undisturbed C P <br />A Aspen .001 7 <br />B Mixed Brush .003 1 <br />S Sagebrush .003 1 <br />WW Western wheatgrass/alkali sage .006 1 <br />SMB Steep Mtn. Brush .006 1 <br />MD/M Mesic Drainage/Meadows .007 7 <br />Disturbance <br />Topsail stripped/pit advance .6 1 <br />Graded spoil/spoil areas .S 1 <br />Area graded, top soiled, seeded on contour .6 .85 <br />Year 1 - reclaimed, veg. establishing .18 1 • <br />Year 3 - reclaimed, veg. established .OS 1 <br />Year 5 - reclaimed, veg. at potential .003 1 <br />13-1-8 <br />