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' topsoil in the azea is relatively stable, with the exception of a few concentrated azeas of <br />erosion. These azeas have the indications of erosion barriers and mitigation implements, <br />' but these structures and mechanisms are deteriorating from continuous weaz. <br />Both of these concerns -erosion and low species diversity - aze, in part, caused by the <br />' steep-sloped "bowl" terrain that characterizes this site. The existence of rills and gullies <br />is to be expected in an azea such asthis - with a slope of about 20% in places and the <br />bowl-shaped azea funneled into one, smaller azea. This bottleneck is where the majority <br />of the erosion is occurring, and consequentially, where there is a reduction in vegetation. <br />However, it was observed that in areas other than this specific bottleneck, there is <br />significant and mature vegetation, so as to reduce the erosion potential of the remainder <br />' ofthe site. <br />' An additional factor contributing to the reduction in species diversity is the fact that the <br />seed list of the reclamation plan was not (with few exceptions) represented by the species <br />found at the site. In contract, several species not listed in the seed mix were in great <br />' abundance on the reclaimed site, such as Crested wheatgrass (introduced) and Rubber <br />rabbitbrush (native). Other species, such as Yarrow (native) and Western wheatgrass <br />(native) were listed in the seed mix, and would have become well-established under these <br />' site conditions, but were not found at all. Therefore, it is believed that the seed mix <br />approved was not the seed mix disbursed at the La Plata No. 1 Mine. <br />IV. Conclusion <br />The reclaimed azea was quantitatively sampled to evaluate revegetation establishment for <br />the final release of liability. Statistical evaluations were calculated, as necessary to <br />evaluate the reclaimed azea's equivalency to the applicable standazd. <br />The reclaimed area meets the revised revegetation success cover, production, and stem <br />density requirements for the final release of liability. With no pre-mine vegetation data <br />to use as a basis for establishing a standazd, CDMG relied on initial baseline vegetation <br />data collected by the mine during the permitting process, Sections 2.04.10 and 2.05.4 of <br />the permit application, and the requirements of Rule 4.15.10. As the revegetation success <br />standazd for previously disturbed mine sites relies on adequacy of ground cover to control <br />erosion and provide cover equivalent to that prior to redisturbance. The cover standard <br />was set at 30 percent, guaranteeing the fulfilhnent ofthe Rule 4.15.10 requirements. <br />This reclaimed azea has a mixture of native perennial graminoid and shrub species - <br />exhibiting a typical Piiion-Juniper community within this region. It is aself-regenerating <br />and permanent vegetation community in the later stages of succession, as illustrated by its <br />extensive native shrub component. High production values for a given reclaimed area <br />demonstrate the azea's ability to provide the necessary resources for plant success and the <br />seeded plants' abilities to effectively utilize those resources. <br />Based on quantitative sampling performed at the La Plata No. 1 Mine in July of 2002, it <br />is evident that a successful and permanent vegetation cover of the same seasonal variety <br />