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Mean Total Hydrologic Cover, 2006-2009 Phase II Vegetation Data <br />Year /Area Plant cover Litter <br />cover Total hydrologic cover <br />2006 Reclaim 43.4 44.3 87.7 <br />2006 Mtn Shrub 39.9 48.9 88.8 <br />2006 Sagebrush 32.6 45.8 78.4 <br />2007 Reclaim 66.8 21.1 87.9 <br />2007 Mtn Shrub 56.3 33.6 89.9 <br />2007 Sagebrush 57.2 29 86.2 <br />2008 Reclaim 71.5 22.2 93.7 <br />2008 Mtn Shrub 63 31.3 94.3 <br />2008 Sagebrush 57.8 25.6 83.4 <br />2009 Reclaim 69.7 21.6 91.3 <br />2009 Mtn Shrub 61.3 33.2 94.5 <br />2009 Sagebrush 48.3 37.2 85.5 <br /> Four Year Mean Total <br />Cover C factor <br />Reclaim mean 90.1 .007 <br />Mtn Shrub mean 91.9 .005 <br />Sagebrush mean 83.4 .011 <br />In Section 4 of the SL-04 application, Colowyo provided Table 4 - Pre-mining vs <br />Reclaimed Post-mining Annual Sediment Production. This table shows the premining <br />soil loss for all Phase II reclamation blocks is 649.7 tons/year over the 432.7 acres (or <br />1.50 tons/acre/year). The table shows that the post-mining soil loss for all Phase II <br />reclamation blocks is 65.1 tons/year over the 432.7 acres (or 0.15 tons/acre/year). The <br />premining sediment less is 100 times greater than the post-mining sediment loss, which is <br />not possible. The Division performed a quick estimate of the soil loss for the Gulch A <br />watershed, which is basically the area requested for Phase II and Phase III Bond <br />Releases, based on the recent cleaning of the Gulch A Pond. This estimate is detailed <br />below. <br />The Gulch A Pond was cleaned in September 2010 and approximately 2,340 cubic yards <br />of sediment was removed from the pond. The last time the Gulch A Pond was cleaned <br />was in November 2006, which was 48 months ago. The total contributing area for the <br />Gulch A Pond is 718.09 acres. The Division assumed that the sediment was earth, dry <br />packed, with a weight of 2,800#/CY or 1.4 tons/CY (weight data from CAT Handbook, <br />Volume 40). <br />(2,340 CY of Sediment) x (1.4 tons/CY) = 3,276 tons sediment <br />(3,276 tons)/(718.09 acres)/(4 years) = 1.14 tons/acre/year sediment <br />The above calculation for sediment loss for the Gulch A watershed, of 1.14 <br />tons/acre/year, shows that the calculated value of 0.15 tons/acre/year for the reclaimed