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2.1.4 COVER FACTOR (C) <br />The cover factor in the USLE accounts for the effect of plant and litter cover on the <br />ground surface in reducing erosion by intercepting raindrops and reducing direct <br />contact with the soil. For the varying vegetation types such as that at the Elk Creek <br />Mine, Table 2 (Wishmeier and Smith, 1978) was used in conjunction with the 2020 <br />reclaimed areas and extended reference area quantitative vegetation data from the <br />vegetation sampling to develop the appropriate factor values. <br />Within the reclaimed areas, the mean total vegetation cover is comprised largely of <br />sod -forming and bunch grasses with spreading bases, large persistent perennial and <br />biennial forbs, and standing litter. These types of vegetation provide significant <br />cover contacting the ground surface. This vegetation community fits within the "no <br />appreciable canopy" category, Type G of Table 2 (Wishmeier and Smith, 1978). <br />Herbaceous cover of the reclaimed areas generally falls between 50 and 64 percent, <br />while ground cover (herbaceous vegetation plus litter ranges from 76 to 92 percent <br />(Savage and Savage, 2020). C factor values were derived from Table 2 (Wishmeier <br />and Smith, 1978) through interpolation and are presented in Table A. <br />At the undisturbed adjacent extended reference area mountain shrub vegetation <br />community, the vegetative cover is a mixture of short trees and tall shrubs with <br />little to moderate understory brush, and a very sparse herbaceous component <br />(Savage and Savage, 2020). This vegetation community falls into the category of <br />communities with "Trees but no appreciable low brush", and includes the W type <br />of Table 2 (Wishmeier and Smith, 1978). <br />From the categories in Table 2 (Wishmeier and Smith, 1978), canopy coverage of <br />the mountain shrub community ranges between 62 and 86 percent in the "Trees but <br />no appreciable low brush" category, with Percent Ground Cover between 0 and 20 <br />percent. Individual reclaimed area C factor values were derived from Table 2 <br />(Wishmeier and Smith, 1978) through interpolation and are presented in Table A. <br />2.1.5 CONTROL PRACTICE FACTOR (P) <br />This factor is used to identify those soil conservation and sediment control practices <br />which affect the level of sediment generated from a site (e.g., ditches, ponds, <br />sediment traps). In this comparison we are interested in the sediment generated <br />from the reclaimed site above such structures, as if they had been removed. <br />Likewise, for the undisturbed area, there are no such controls. Therefore, for the <br />purposes of our comparison, a value of unity (one) (Barfield, Warner and Hahn, <br />1983) will be assigned this factor, rendering no impact to our calculations. <br />............................................................................. <br />............................................................................. <br />Oxbow Mining, LLC Elk Creek Mine Page 5 <br />Phase 11 Bond Release Sedimentology Evaluation 2020 <br />