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WO 15 as a whole. All three of the reclamation parcels met the requirements for their requested <br />Phased Bond release as summarized in this document below. <br />All reclamation parcels contained in SL -14 being requested for Phase R bond release were sampled <br />in 2016 or 2017 in accordance with the vegetation monitoring plan, detailed in Volume 1, Section <br />4.15 in the Colowyo PAP. Sample adequacy was determined using the Cochran formula. Both the <br />sampling plan and the sample adequacy determination are acceptable to the Division. <br />SedimentolM <br />The Division reviewed the sedimentology evaluation provided in the SL -14 application. As per <br />Rule 4.15.1(2)(b), vegetation cover shall be capable of stabilizing the soil surface to achieve erosion <br />control equal to pre -mining levels. In addition, Rule 3.03.1(3)(b) states that lands which to which <br />the release would be applicable are contributing suspended solids to streamflow or runoff outside <br />the permit area in excess of pre -mining levels as determined by baseline data. To demonstrate this, <br />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. Results <br />of this demonstration as well as vegetative cover results are summarized below. <br />Phase II Bond Release Parcel Results — WPO 15, WPO 17, WPO 18, WPO 19 and WP020 <br />2017 Cover: Herbaceous cover: 29.88% <br />Herbaceous cover standard (90%): 20.88% <br />The 2017 sample data successfully exceeds 90% of the herbaceous cover <br />standard. <br />2017 Sedimentology: Post -Mining: 0.176 tons/acre/year <br />Pre -Mining: 0.302 tons/acre/year <br />The 2017 sedimentology evaluation data shows post -mining condition <br />sediment loss to be less than pre -mining conditions. <br />Phase II Bond Release Parcel Results — WP014 and WPO 16 <br />2016 Cover: Herbaceous cover: 31.93% <br />Herbaceous cover standard (90%): 18.29% <br />The 2016 sample data successfully exceeds 90% of the herbaceous cover <br />standard. <br />2016 Sedimentology: Post -Mining: 0.099 tons/acre/year <br />Pre -Mining: 0.378 tons/acre/year <br />The 2016 sedimentology evaluation data shows post -mining condition <br />sediment loss to be less than pre -mining conditions. <br />Proposed Decision and Findings of Compliance October 2018 <br />Partial Phase II and III Bond Release SL -14 Page 8 <br />