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• <br />use! and treatment. Soils having the highest K value are the most erodible. The K <br />value used for this calculation is picked from the U.S. Department of Agriculture Soil <br />Survey, San Miguel Area, and is based on the soils classification; Barx. The K factor of 0.24 <br />is the same for both the reclaimed slope and the adjacent natural slope. <br />LS (length and percent slope) factors account for the length and percent slope. These <br />factors are taken from Table 1. Length of slope begins at the top of the micro <br />watershed. This is usually at the top of a hill, ridge, terrace or diversion. The length of <br />slope is considered to end for a given field at one of the following places: (1) the point <br />where the slope decreases to the extent that deposition occurs, (2) the point where <br />runoff enters a well- defined channel, gully, terrace or diversion , or (3) where water <br />leaves the field. The LS for the reclaimed slope was measured near the southern end of the <br />re- seeded area, where the disturbed area length is about 1200 -feet and the slope is about 3 %. <br />Reclaimed <br />Length Percent Slope (S) <br />of Slope <br />2.0% 2.8% 3.0% <br />1200 0.420 0.732 0.810 <br />1217 LS - Factor 0.734 <br />1300 0.430 0.742 0.820 <br />The LS factor for the adjacent area was measured east of Mining Area No.1, and parallel to the <br />re- seeded area LS, where the disturbed area length is about 1200 feet and the slope is 2.5 %. <br />• Adjacent <br />Length Percent Slope (S) <br />of Slope <br />2.0% 2.5% 3.0% <br />1200 0.420 0.615 0.810 <br />1217 'LS" Factor 0.617 <br />13001 0.430 0.625 0.820 <br />C (cropping - management) factors are the ratios of soil losses from lands cropped <br />under specified conditions to the corresponding losses from tilled, continuous fallow. C <br />factors for land uses other than cropland are included on Figures 7,8, and 9. The <br />percent ground cover is the primary item to consider because a slight change in the <br />percent ground cover will result in a significant change in the erosion prediction. <br />Figure 7 - "C Factors for Permanent Pasture and Rangeland <br />ADJACENT AREA - "C FACTOR <br />No appreciable canopy. Canopy is assumed to be the combined cover contributed by trees and shrubs. <br />Based on the 2009 Vegetation Evaluation the combined tree and shrub cover totals 8.7 %. The percent <br />ground cover for the adjacent area shown on the preceding page is 47.5 %. Use figure 7 identified <br />above and interpolate to determine the C factor for 47.5% cover. <br />• <br />MR -11 2.05 -8v <br />M,P- I! <br />1111b 01 <br />10/0 <br />