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Ground cover of Mine Area No. 1 in 2010 consisted of 35.7% live vegetation, 0.1% <br />crypotobiotic soil crust, 0.4% rock, 13.4% litter and bare ground exposure of 50.4%. <br />Perennial cover across the unit averaged 30.7% with annual and biennial cover averaging <br />5.0%. Dominant species were needle and thread grass, Indian 'rice grass, scarlet <br />globemallow and blue grama grass. <br />Ground cover of the Mine Area No. 3 consisted of 32.4% live vegetation, 0.4% <br />cryptobiotic soil crust, 1.4% rock, 15.7% litter, and bare ground exposure of 50.0%. <br />Perennial cover across the unit averaged 22.6%, with annual and biennial cover averaging <br />10.2%. Dominant taxa were Russian thistle, blue grama grass, Indian ricegrass and <br />scarlet globemallow. <br />The perennial cover of the Sagebrush reference area A was 22.5%, Sagebrush reference <br />area B was 19.2% and the grassland reference area was 23.3%. Therefore, the weighted <br />cover standard for Mine Area No. 1 is 22.6% perennial vegetation cover. The weighted <br />standard for Mine Area No. 3 is 20.9% perennial vegetation cover. <br />Results: Perennial vegetative cover on Mine Area 1 parcel was 30.72 %, exceeding the <br />weighted mean standard from the sagebrush reference area A and grassland reference <br />area of 22.6%. Vegetation establishment is deemed successful on the Mine Area 1 parcel <br />for Phase II bond release. Perennial vegetative cover on Mine Area No. 3 was 22.6% <br />exceeding the 20.9 % weighted mean perennial cover of the sagebrush reference areas. <br />Vegetation establishment is deemed successful on the Mine Area 3 parcel for Phase II <br />bond release. <br />Although some portions of the reclamation still retain a higher percentage of annuals than <br />is often seen in a permanent stand eight years or older, removing that portion of the cover <br />value attributed to annual and biennial species,. the reclaimed area still exceeds the <br />weighted reference area standard. The vegetative species established on the reclaimed <br />area support the post-mining land use and the 2010 data show that the established <br />vegetation would exceed the approved diversity standard. Although the operator is not <br />required to demonstrate adherence with meeting the diversity standard during Phase II <br />Bond Release, the Division evaluates if the reclaimed community is trending towards a <br />diverse perennial community. <br />C. Suspended Solids Demonstration <br />A soil loss demonstration for the reclaimed disturbed area was incorporated into section <br />2.05.3(4) of the permit with the approval of Technical Revision No. 10 (TR-10) and Minor <br />Revision No. 11 (MR-11) in 2009. The contribution of suspended solids to streamflow <br />outside the permit area was evaluated by comparison of vegetation cover within the permit <br />area to an adjacent undisturbed area. The Universal Soil Loss Equation was utilized to <br />estimate the sediment loss from the two areas. The results indicate that the revegetated area <br />may lose 0.31 tons per acre per year to erosion, while the baseline conditions may lose 0.35 <br />tons per acre per year. The calculations demonstrate that untreated drainage from the <br />reclaimed area will contribute fewer suspended solids to streamflow or runoff outside the <br />6