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Vegetation Success The approved Meadows No. 1 Mine permit application specifies that vegetative cover success will be determined through comparisons to reference areas. The permit application package specifies the use of two reference areas for comparison. For land owned by the Eiltses, the Mountain Brush Reference Area will be used. For land owned by Grassy Creek Coal Company, the Sage/Grass Reference Area will be used. In order for vegetation to be considered successful, it must be demonstrated that cover on the reclaimed area is not less than 90 percent of the cover on the applicable reference area with 90 percent statistical confidence (Rule 4.15.8(3)(a)). Vegetative cover is used to determine successful establishment of vegetation, as required by Rule 3.03.1(2)(b). Vegetative cover data collected by the operator were reviewed. The revegetation sampling results (collected in August, 1994) for the Meadows No. 1 Mine Phase II bond release application submitted by Sun Coal Company indicate the cover and diversity of the vegetation on the Grassy Creek property meets the relevant success standards based on reference area comparisons. Sun Coal estimated vegetative cover in the Sage/Grass Reference Area was 52.2%. Vegetative cover in the Grassy Creek owned reclaimed area was estimated to be 47.3%, which is greater than 90% of the reference area cover. A small (0.53% cover) component of cover on the Grassy Creek property was due to a noxious weed (Canada thistle). The Division does not generally account for cover due to noxious weeds in estimates of vegetative cover on reclaimed areas. Excluding thistle, cover on the reclaimed area is 46.80%. This is less than the 46.98% cover on the Sage/grass reference area. However, analysis of this difference by the Student's t-test at the 90% confidence level indicates this is not a significant difference. Therefore, the reclamation on the Grassy Creek property meets the relevant success standard for vegetative cover in regard to Phase II bond release. While there is enough Canada thistle on the site to require some future weed control, particularly on the recently reclaimed lateral furrows, there is no serious infestation. The Meadows No. 1 Mine permit application package specifies a diversity success standard which requires the presence of at least five perennial species with relative importance (cover) of at least three percent, with all of these species together not exceeding 75% relative importance nor any one species exceeding 40% relative importance. Sun's 1994 study found each of eight perennial species contributing from 3- 26% relative cover. The community was dominated by smooth brome (22.73% relative cover), titer milkvetch (26.05%), sheep fescue (11.05%), and five other grasses (wheatgrasses and bluegrass). The five most prevalent species in the community account for 72.79% of the relative cover. 1992 sampling by DMG found an average of 48.4% cover on Grassy Creek property Meadoac No. 1 Mine 5 Phasc 11 Bond Relesu