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<br />6 <br />As this mine site was disturbed prior to 1977, no pre-mining vegetation data was collected. <br />Vegetation data collected in August 1995 reports a mean live vegetative cover of 44.93%. <br />Additionally, litter accounted for 20.27% cover, and 5.33% cover was attributed by rock. This <br />leaves a balance of 29.47% bare ground. The range site descriptions do not describe the <br />proportion of litter, rock and bare ground. <br />Eighteen percent (18%) of the 44.93% live vegetative cover on the site is composed of <br />graminoids, 6.93% comprised of forb species, and 20% shrubs species. Adjusting for the <br />exclusion of "weedy" annuals and biennials,Bromus tectorum and Melilotus officina/is, the adjusted <br />live vegetative cover is still 41.47%. <br />Rule 3.03.1(2)(b) provides that "up to 85% of the applicable bond amount shall be released <br />upon the establishment of vegetation which supports the post-mining land use and which meets <br />the approved success standard for cover, pursuant to 4.15.8...:' <br />Ruie 4.15.8(1)(b) provides for standards on previously mined lands applicable to Rule 4.15.10 <br />shall apply. <br />Rule 4.15.10(1) states that "For previously mined areas that were not reclaimed to the <br />requirements of these Rules, at a minimum, ground cover of living plants shall not be less than <br />can be supported by the best available topsoil or other suitable material in the reaffected areas, <br />shall not be less than the ground cover existing before redisturbance, and shall be adequate to <br />control erosion". <br />Additionally, Rule 3.03.1(3)(b) states that "No more than 60% of the bond shall be released so <br />long as the lands to which the release would be applicable are contributing suspended solids to <br />streamflow or runoff outside the permit area in excess of levels determined by baseline data or <br />in excess of levels determined on adjacent non-mined areas...." <br />Although the vegetation does not meet the previously mentioned Division imposed standard of <br />70% live vegetative cover, the Division considers this required standard unsupported due to area <br />NRCS Range site description cover values. the applicant has demonstrated that the reclamation <br />achieved at the La Plata Mine meets the requirements of Rule 4.15.10, and through modelling <br />using the USLE formula, that Rule 3.03.1(3)(b) is complied with, as well. Furthermore, the <br />applicant has demonstrated the vegetation established is composed of a diverse mixture of <br />graminoid, forb and wood shrub components. Of the 16 species identified in the sampling <br />report, 38% of these are considered native species. Although four species, Bromus tectorum, <br />Carduus nutans, Melilotus off~cinalu, and Tragopogon dubius, are considered "weedy" species and <br />are indicative of early successional vegetation, these species only account for 3.86% of the total <br />vegetative cover. This low percentage of cover attributed to these species indicates that these <br />"weedy" species are not dominant on the site and that the preferred perennial species have <br />become established. <br />