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Colowyo provided estimation on soil loss based upon post-mining site specific data using the <br /> Revised Universal Soil Loss Equation(RUSLE). Results from the RUSLE were then compared to <br /> baseline data from each of the reclamation blocks being requested for Phase II bond release. <br /> Results of this demonstration as well as vegetative cover results are summarized below. <br /> Phase II Bond Release Parcel Results—EP058 <br /> 2018 Cover: Herbaceous cover: 24.60% <br /> Herbaceous cover standard(90%): 14.99% <br /> The 2018 sample data successfully exceeds 90% of the herbaceous cover <br /> standard. <br /> 2018 Sedimentology: Post-Mining: 0.802 tons/acre/year <br /> Pre-Mining: 0.945 tons/acre/year <br /> The 2018 sedimentology evaluation data shows post-mining condition <br /> sediment loss to be less than pre-mining conditions. <br /> Phase II Bond Release Parcel Results—ST002 and ST003 <br /> 2018 Cover: Herbaceous cover: 20.10% <br /> Herbaceous cover standard(90%): 18.10% <br /> The 2018 sample data successfully exceeds 90% of the herbaceous cover <br /> standard. <br /> 2018 Sedimentology: Post-Mining: 0.400 tons/acre/year <br /> Pre-Mining: 0.366 tons/acre/year <br /> The 2018 sedimentology evaluation data shows post-mining condition <br /> sediment loss to be less than pre-mining conditions. <br /> Phase III <br /> Post-mining Land Use <br /> The post-mining land use at the Colowyo mine is rangeland and wildlife habitat. The Phase III <br /> Bond Release areas requested with the SL-16 application were walked during the inspection. Both <br /> the East Side Collection Ditch and the Gulch A Pond have been retained as permanent structures in <br /> support of the post-mining land use. While Colowyo has not used the reclaimed lands for domestic <br /> livestock grazing,there is a large resident elk herd that uses the reclaimed lands extensively. There <br /> are also several smaller herds of deer and pronghorn that use the reclaimed East and West Pit. The <br /> wildlife use includes grazing(including winter grazing) and calving areas. <br /> Summary and Conclusions <br /> Proposed Decision and Findings of Compliance October 22,2019 <br /> Partial Phase I,II and III Bond Release SL-16 Page 11 <br />