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areas is probably off by two orders of magnitude. The US average for soil loss for <br />cropland is 4.3 7, pastureland is 1.29, forest is .9 1, and other including farmsteads, mines, <br />quarries, and pits is 8.46 (all values in tons/acre/year). An estimate of soil loss can be <br />found at: http://www.fishwild.vt.edu/haas/haasydf/usle.pdf <br />Adequacy Questions <br />5. Based on the information in the discussion above, please revise the vegetative <br />cover factor, the "C" factor, in Table 4 for both the premining and post-mining <br />conditions. Please use site-specific data from the 2006-2009 vegetation sample <br />years to justify the "C" factors. Please recalculate the average annual soil loss in <br />RUSLE using the new "C" factors. Please provide the Division with the revised <br />pages in Section 4 of SL-04 justifying the "C" factors and please provide and <br />updated Table 4 with the new "C" factors and revised soil loss calculations. <br />6. Based on the information in the discussion above, please revise the conservation <br />practice factor, the "P" factor, in Table 4 for the post-mining conditions. Please <br />use site-specific information to justify the "P" factor. Please recalculate the <br />average annual soil loss in RUSLE using the new "P" factor. Please provide the <br />Division with the revised pages in Section 4 of SL-04 justifying the "P" factor and <br />please provide and updated Table 4 with the new "P" factor and revised soil loss <br />calculations. <br />This completes the Division's adequacy review of the Colowyo Partial Phase II Bond <br />Release SL-04. Please contact me at 303-866-3567 X8145 if you have any questions. <br />Sincerely, <br />James R. Stark <br />Environmental Protection Specialist <br />cc: Sandy Brown <br />Kurtis Blunt