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transport of solids in suspension; therefore, the comparison indicates the untreated drainage, <br />currently, does not yield more suspended solids than prior to mining. For the Phase II bond <br />release areas in SL-01, BRL calculated an adjacent area sediment yield rate for three adjacent <br />areas: the Mesic Mountain Shrub, the Xeric Mountain Shrub, and the Aspen. The adjacent area <br />sediment yield rates were 1.15 tons per acre per year (Mesic Mountain Shrub), 1.76 tons per acre <br />per year (Xeric Mountain Shrub), and 1.17 tons per acre per year (Aspen). The reclaimed drill <br />pads and access roads sediment yield rate was calculated at a post-mining rate of 0.24 tons per <br />acre per year. The considerable difference between these two calculated rates indicates the post- <br />mining rate is significantly less than the adjacent undisturbed area rate. This conclusion is only <br />valid if BRL used reasonable variables in the USLE calculations. The Division finds that the <br />variables used in the calculations are reasonable for making the comparison; as such, the <br />comparison appears technically valid. <br /> <br />Observations made during the bond release inspection, as well as observations made during <br />previous inspections, indicated that the vegetation on the reclaimed slopes had stabilized the soil. <br />There was no major erosional instability observed. The Division’s field observations appeared to <br />corroborate BRL’s hydrologic modeling results of post-mining sediment yields being less than <br />pre-mining yields. <br /> <br />Based on BRL’s USLE modeling using baseline data, the Division finds that the 45.33 acres <br />proposed for Phase II bond release are not contributing suspended solids to streamflow or runoff <br />outside the permit area in excess of pre-mining levels. <br /> <br />Summary and Conclusions <br /> <br />Based upon a review of the mine permit, the applicant's bond release application, and site <br />inspections, the Division finds that Bowie Resources, LLC has replaced topsoil in accordance with <br />the approved reclamation plan. Bowie Resources, LLC has established vegetation which supports <br />the approved post mine land use and meets the approved success standard for vegetative cover. The <br />Division finds that the 45.33 acres subject to a Phase II release under SL-1 is not contributing <br />suspended solids to streamflow or runoff outside the permit area in excess of pre-mining levels or in <br />excess of adjacent non-mined areas. <br /> <br />PHASE III <br /> <br />With regard to Phase III bond release, all disturbed area acreage associated with Phase III bond <br />release is within the Freeman Gulch rock slide area. In July 2007, a large rockslide occurred in <br />the area of the Freeman Gulch vent fan pad. The area of the rockslide covered approximately 38 <br />acres and permanently destroyed and covered the Freeman Gulch vent shaft pad (1.0 acre). <br /> <br />In addition, drill sites GVB-D2-C (0.4 acres of road and 0.2 acres of pad), GVB-6C (0.5 acres of <br />pad), GVB-D3-B (0.2 acres of road and 0.5 acres of pad), and GVB-D4-A (0.4 acres of road and <br />0.3 acres of pad) have been identified as disturbed, with the approved disturbance falling within <br />the disturbance of the Freeman Gulch permanent road. Site Geo-Tech-04 (0.6 acres of pad) falls <br />within the approved disturbance area of the Hubbard Creek vent shaft pad disturbance. Due to <br />the circumstances of the rockslide and the approved disturbances associated with the reclaimed