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The dominant plant species was Chrysothamrms nauseosus (rubber rabbitbrush) at 18.9 <br />percent mean cover (55.8 percent relative cover). Two additional species provided <br />significant additional cover (greater than three percent relative cover). Those species <br />were: Agropyron cristatum (crested wheatgrass) with 11.2 percent mean cover (33.0 <br />percent relative cover) and Oryzopsis hymenoides (Indian ricegrass) with 1.7 percent <br />mean cover (4.9 percent relative cover). Vegetative litter (prior year's growth, dead <br />wood, and other biologic organic material) comprised 27.8 percent ground cover within <br />the reclaimed area. Baze soil comprised 27.5 percent of the ground cover encountered. <br />Rock material was encountered 10.7 percent of the time during cover sampling at the <br />reclaimed area. <br />The vegetation measured at this site was developed beyond the cover standazd set and the <br />amount expected to be detected. <br />3.3 Species Composition <br />' The total number of plant species encountered during cover sampling was eleven. <br />Graminoids accounted for five species, forbs four species, and shrubs two species. Of the <br />species encountered five were native and six were introduced. Eight of the eleven <br />' species encountered were perennial. Seasonality of the reclaimed azea species was nearly <br />entirely cool (ten of eleven species). <br />' 3.4 Erosion <br />The lack of annual or invader species dominating the cover connotes the stable nature of <br />' the reclaimed azea. The surface material in the area is relatively stable, with the <br />exception of a few small areas of erosion. <br />Both of these concerns -erosion and low species diversity -are, in part, caused by the <br />steep-sloped "bowl" terrain that chazacterizes this site. The existence of rills and gullies <br />is to be expected in an area such as this - with a slope of about 20% in places and the <br />bowl-shaped azea funneled into one, smaller azea. <br />4.0 Conclusions <br />The reclaimed area 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 area's equivalency to the applicable standazd. <br />The reclaimed area meets the revised revegetation success cover requirement for the final <br />release of liability. With no pre-mine vegetation data to use as a basis for establishing a <br />standard, CDMG relied on initial baseline vegetation data collected by the mine during <br />the permitting process, Sections 2.04.10 and 2.05.4 of the permit application, and the <br />requirements of Rule 4.15.10. As the revegetation success standard for previously <br />disturbed mine sites relies on adequacy of ground cover to control erosion and provide <br />La Plata # 1 Mine Page 6 <br />2A03 Vegetation Sampling <br />