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The sites for which phase II bond release has been applied for with SL-6 were reclaimed between 2002 <br /> and 2018. Stockpiled topsoil was spread before the sites were seeded with the Oxbow seed mix. <br /> Topsoil depths were measured at 15 locations during vegetation sampling in 2021,using a 2'/4 inch auger <br /> to determine the depth from the surface to the C-horizon. The range was 9.5"to 25"and the mean depth <br /> was 14.4". <br /> In the Vegetation Sampling Report submitted with the SL-6 application, 15 samples were reported from <br /> the extended reference area and 21 from the reclaimed area,which satisfied sample adequacy. The <br /> extended reference area was a juniper woodland community dominated by a discontinuous woody <br /> canopy with large open areas between tree groups. A sparse shrub and herbaceous layer lay beneath and <br /> between the tree groups. The extended reference area was immediately adjacent to the reclaimed areas. <br /> Total live vegetation cover of 44.13%was reported,but herbaceous vegetation cover(the revegetation <br /> success criterion)was 13.33%. <br /> In the reclaimed area total live vegetation cover of 54.00%was reported; a value which includes several <br /> noxious weed species:Bromus tectorum, Cheatgrass (9.14%); Cardaria draba, Whitetop(0.38%); <br /> Carduus Nutans,Musk Thistle(0.10%); and Convolvulus arvenssis, Field Bindweed(0.10%). Noxious <br /> weed cover was 9.72% in total, (relative cover of 18%). Native or non-noxious weed cover was 44.86% <br /> in total, (relative cover of 82%). The data shows that vegetative cover in the reclaimed area satisfies the <br /> revegetation success criteria(greater than 90% of the total herbaceous cover of the extended reference <br /> area). <br /> The sedimentology evaluation projects a mean sediment yield for the reclaimed area of 0.312 <br /> tons/acre/year,with a range of 0.003-1.758 tons/acre/year. The projected mean sediment yield for the <br /> adjacent undisturbed extended reference area was 0.824 tons/acre/year,with a range of 0.317-2.393 <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, <br /> the Division finds that Oxbow Mining,LLC has replaced topsoil in accordance with the approved <br /> reclamation plan. Oxbow Mining, LLC has established vegetation which supports the approved post <br /> mine land use and meets the approved success standard for vegetative cover. The Division finds that the <br /> reclaimed area subject to this bond release is not contributing suspended solids to streamflow or runoff <br /> outside the permit area in excess of premising 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 35.63 acres identified in <br /> Table 1. <br /> The Division currently holds a performance bond of$2,000,000 for the Elk Creek Mine. The most <br /> recent update of reclamation liability for the site prior to SL-1 was$4,323,977.80. This will be the <br /> C-1981-022,SL-6 Page 7 of 9 <br />