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I bond release. <br /> Although erosional features were noted during the inspection, in general, erosion is not a problem in <br /> the SL22 bond release parcels. Erosional features were brought to the attention of the operator and <br /> were repaired in a timely manner as described in DRMS's October 2020 inspection report. <br /> Cover and Species Composition <br /> Vegetative cover was sampled in 2020 for all parcels included in the SL22 application. Vegetation <br /> cover was measured with systematically located transects and an optical point bar using a point-hit <br /> technique. A 10-point frame was placed at 10 locations along each 50-meter transect for a total of 100 <br /> data points per transect. The sampling method used meets the criteria outlined in Rule 4.15.11(1) and <br /> the permit application. <br /> The Bond Release Block consists of seven parcels. The vegetative cover monitoring results from all <br /> seven parcels included in the BRB were compiled. The total vegetative cover for the 175 acres was <br /> 58.6%, with vegetative litter measured at 31.3%. Based upon criteria defined in the permit, removal <br /> of cover attributed to noxious weed species,and allowing no more than 10%relative cover from annual <br /> and biennial species, the allowable cover from the 2020 sampling achieved 66.0% cover. The <br /> reclamation success standard for the BRB is 52%. The SL22 Bond Release Block meets the cover <br /> standard. <br /> The vegetation report shows that the reclaimed parcels are dominated by native perennial grasses. <br /> Native perennial graminoids account for 31.3% absolute cover. Of the graminoid cover, 15.3% is <br /> composed of Wheatgrasses (Agropyron spp.), Great Basin Wildrye (Elymus cinereus, constituted <br /> 6.8%, 2% cover was Mountain Brome and 1.7% cover was attributed Kentucky Bluegrass (Poa <br /> pratensis. Perennial forbs accounted for 5% cover, annuals and biennial forbs made up 10.2% cover, <br /> woody species accounted for 4.8% cover. Noxious perennial weeds accounted for 1.2 %. Cheatgrass <br /> (Bromus tectorum), accounted for 6.4% cover, however, given the established cover of desirable <br /> species,it is likely that cover from Cheatgrass decreases overtime. Table 1.2-2 in the SL22 application <br /> provides a summary of the species and life forms sampled. Although, species diversity is not a <br /> requirement for phase 11 bond release, the establishment of a diverse and effective reclaimed <br /> community that supports the post mining land use, allows the Division to confirm that the reclaimed <br /> area is moving towards final reclamation success. <br /> Based on the perennial species of grasses, forbs and shrubs found at the site as indicated in the <br /> SL22 application, the species diversity and composition will support the post-mine land use. While <br /> noxious weeds were encountered at the site, they comprised a small percentage of the vegetative <br /> cover. <br /> To demonstrate that runoff from the reclaimed parcels will result in equivalent or lesser sediment <br /> contributions as compared to baseline conditions at the mine, TMI submitted two sediment loss <br /> evaluations; one based on the Universal Soil Loss Equation (LISLE), and a second utilizing <br /> SEDCAD analysis. The USLE provides a basis for predicting the gross erosion per acre from an <br /> area on an annual basis. SEDCAD modeling evaluates both runoff and erosion estimates and <br /> Permit Number C1981010 <br /> SL22 Page 10 of 18 <br />