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point-intercept method. Cover transects were 25 m long,with sample data points collected at 1 m intervals, <br /> on either side of the transect, spaced 1.5 m apart (giving 50 data points per transect, each reported by <br /> individual plant species). Each transect corresponds to a single sample unit. <br /> The boreholes,pads and roads for which phase II bond release has been applied for with SL-3 were <br /> reclaimed between 2015 and 2017. Stockpiled topsoil was spread uniformly,before the sites were <br /> seeded with the appropriate seed mix, as specified by the land owner/manager. Topsoil depths were <br /> measured at 15 locations during vegetation sampling in 2020,using a 2'/4 inch auger to determine the <br /> depth from the surface to the C-horizon. The range was 10"to 25.5" and the mean depth was 16.4". <br /> In the Vegetation Sampling Report submitted with the SL-3 application, 15 samples were reported from <br /> the extended reference area and 15 from the reclaimed area,which satisfied sample adequacy. The <br /> extended reference area was predominantly a dense mountain shrub community, dominated by a dense <br /> woody canopy with scattered openings and a sparse shrubby and herbaceous understory. Total live <br /> vegetation cover of 86.13%was reported,but herbaceous vegetation cover(the revegetation success <br /> criterion)was 11.06%. <br /> In the reclaimed area total live vegetation cover of 55.07%was reported; a value which includes several <br /> noxious weed species:Bromus tectorum, Cheatgrass (0.4%); Cirsium arvense, Canada Thistle(1.07%); <br /> Cirsium vulgare,Bull Thistle(0.40%); and Convolvulus arvenssis,Field Bindweed(0.13%). Noxious <br /> weed cover was 2.00%in total, (relative cover of 3.63%). Native or non-noxious weed cover was <br /> 53.07%in total, (relative cover of 96.37%). The data shows that vegetative cover in the reclaimed area <br /> satisfies the revegetation success criteria(greater than 90% of the total herbaceous cover of the extended <br /> reference area). <br /> The sedimentology evaluation projects a mean sediment yield for the reclaimed area of 0.352 <br /> tons/acre/year, with a range of 0.055-1.604 tons/acre/year. The projected mean sediment yield for the <br /> adjacent undisturbed extended reference area was 2.175 tons/acre/year, with a range of 0.043-13.695 <br /> tons/acre/year. <br /> Summary and Conclusions <br /> Based upon a review of the mine permit,the applicant's bond release application, and site inspections,the <br /> Division finds that Oxbow Mining,LLC has replaced topsoil in accordance with the approved reclamation <br /> plan. Oxbow Mining, LLC has established vegetation which supports the approved post mine land use <br /> and meets the approved success standard for vegetative cover. The Division finds that the reclaimed area <br /> subject to this bond release is not contributing suspended solids to streamflow or runoff outside the permit <br /> area in excess of premining levels or in excess of adjacent nonmined areas. <br /> IV. PROPOSED DECISION <br /> Based on the observations above,the Division proposes to approve Oxbow Mining,LLC's request for a <br /> Partial Phase II bond release for the Elk Creek Mine. This proposed decision will release the applicant <br /> from liability for topsoil redistribution and establishment of vegetation for the 50.44 acres identified in <br /> Table 1. <br /> C-1981-022,SL-3 Page 8 of 10 <br />