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verified. Figures 4 and 5 of this document show the location of each hole. All topsoil <br /> verification holes dug were approximately at or greater than the stated depth in the SL-16 <br /> application. <br /> Topsoil verification holes were not dug for the East Side Collection Ditch and Gulch A Pond as <br /> they have been permitted as permanent structures. <br /> Vegetation Cover <br /> The Colowyo Mine uses three reference areas for the comparison of success of their SL-16 <br /> reclamation parcels. The reference areas are the sagebrush reference area,the mountain shrub <br /> reference area and the aspen woodland reference area. Success standards are based on weighted <br /> average of the pre-mining vegetation communities in each reclamation block(as shown on Map 3 <br /> and 4 in Colowyo's PAP). <br /> Permit Page 4.15-18 states that the"...herbaceous cover of the revegetated area will be considered <br /> adequate for final bond release if it is not less than 90% of the herbaceous cover as determined from <br /> the reference areas with 90% statistical confidence utilizing a standard student's statistical t-test <br /> comparison of the means." <br /> During the SL-16 inspection,the Division observed four areas where rill repair had occurred within <br /> the requested East Pit Parcel EP058. The repair work is considered normal husbandry practices and <br /> the area is well below five percent of the total area of parcel EP058. Due to this,the liability time <br /> for these areas are not affected as sated by Rule 4.15.7(5)(a). Additionally, the area of the rill repair <br /> in EP058 is not representative of that reclamation parcel as a whole. <br /> All reclamation parcels contained in SL-16 being requested for Phase II bond release were sampled <br /> in 2018 in accordance with the vegetation monitoring plan, detailed in Volume 1, Section 4.15 in <br /> 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 /> Vegetation cover criteria was not evaluated for the East Side Collection Ditch and Gulch A Pond <br /> as they have been permitted as permanent structures. <br /> Sedimentology <br /> The Division reviewed the sedimentology evaluation provided in the SL-16 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 /> Proposed Decision and Findings of Compliance October 22,2019 <br /> Partial Phase I,II and III Bond Release SL-16 Page 10 <br />