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1991, the Division approved Areas I, II and III, and Ponds 1 and 2 for Phase II release, but denied Area IV solely for not having achieved the required regulatory standard for vegetative cover for Phase II release. On October 17, 1995, the Division reviewed this release request for Area IV, which included Pond 3, and found that both Area IV and Pond 3 met the Phase II Bond Release vegetative cover requitement. The approved Canadian Mine permit application specifies that vegetative cover success will be determined by comparison to a sagebrush reference area. In order for vegetation to be considered successful, tbe applicant must demonstrate that cover on the reclaimed area is not less than 90% of the cover in the reference area with 90% statistical confidence (Rule 4.15.8(3)(a)). For Phase II Bond Release, successful establishment of vegetation is determined by successful establishment of vegetative cover. The vegetation sampling results collected in August 1995 by Slurco for the portion of the Canadian Mine which was reclaimed in 1987 indicate vegetative cover on the reclaimed area meets the relevant success standard for the mine. Slurco estimated vegetative cover in the sagebrush reference area to be 46.0%. Cover on the reclaimed site was 44.4%, which is more than 90% of the reference area cover. The Division inspected the Canadian mine site on August 9, 1995 at the time the Slurco vegetation study was being conducted. The applicant estimated vegetative cover by means of point intercept observations with an optical point frame at one-foot intervals along 50-foot-long transects. The methodology of the study agreed with methods described in the approved permit. An adequate number of samples was collected to make the success demonstrations required by the regulations. The results of the study appear congnrent with qualitative observations made at the site during the August 9, 1995 inspection. The Canadian permit also indicates the revegetated community will be deemed successful in terms of diversity when at least six species occur, with a minimum of three cool season grasses, two shrubs and one forb. The permit also indicates cool season grasses will contribute 7% to 35% relative cover, and forbs will contribute 1% to 5% relative cover. Cover on the mine site is predominantly grasses and forbs. Grasses, forbs and shrubs accounted for 65%, 34% and 1% of the relative cover, respectively. According to the Slurco study, 15 cool season grasses account for 65% of the relative cover of the reclaimed area. Six forbs account for 34% relative cover, and one shrub accounts for less than 1% of the relative cover. The predominant species, in terms of cover, are: Relative Absolute S ecies Cover Cover Halli's Milk Vetch (Astragalus hallii) 20.6% 8.9% Western Wheatgrass (Agropyron smithii) 18.3 % 8.1 % CrestedWheatgrass (Agropyroncristarum) 12.1% 5.4% Blue Flax (Linum pererse) 9.6% 4.2% Pubescent Wheatgrass (Agropyron rrichophorum) 8.4% 3.8% Intermediate Wheatgrass (Agropyron intermidium) 8.4% 3.8% 4