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<br />Positive drainage appeared to exist throughout the bond release area during the bond release <br />inspection and subsequent inspections, with the exception of a few depressions on regraded surfaces <br />that are too small to impair the approved postmining residential or commercial land uses. Drainage <br />control in the backfilled areas appeared to have been completed in accordance with the approved <br />reclamation plan. <br />Phase II Bond Release <br />Topsoil replacement. Replaced topsoil depths in the North Pit area were observed during topsoil <br />replacement in 2006 and were found to be more than the one-foot required thickness. Topsoil <br />replacement depths were verified in the Equipment Storage Area and the Permanently Reclaimed <br />Spoil Area during the Division's June 2008 inspection. <br />Revegetation Success <br />Oakridge's consultant sampled the revegetated areas in the bond release area in June 2008. <br />Sampling excluded the areas that have not previously received Phase I bond release because these <br />areas have become eligible for Phases I and II bond release only since sampling was completed. The <br />areas excluded from sampling were: topsoil stockpiles 4 and 7 (approved for permanent retention in <br />Technical Revision16); Ponds 1 and 2 (reclaimed in 2008); the East Collection Ditch (on the east <br />side of the asphalt-paved road); the former Equipment Storage Area; and the collection ditch on the <br />east side of the former Equipment Storage Area. Sampling was not necessary in these areas based on <br />their relatively small areal extent and visual comparison with the adjacent sampled areas. <br />Vegetation sampling of reclaimed areas utilized a plan developed in accordance with Sections <br />2.04.10 and 4.15. The SL-04 bond release application describes the sampling plan and contains the <br />sample data. The plan was designed to ensure randomness of samples and a statistically adequate <br />number of samples. The minimum number of samples (transects) necessary for achieving the 90% <br />confidence level was determined to be two samples. Cover data and species data were collected <br />along fifteen 25-meter point-intercept transects. <br />Mean vegetative cover for the sampled areas was 63.6%. Grass species provided 76.0% relative <br />cover (the percentage of all vegetative cover). Perennial cool season species dominated the grasses, <br />with the most abundant species being intermediate wheatgrass, mountain brome, and western <br />wheatgrass. Additional significant herbaceous cover was provided by thickspike wheatgrass and <br />crested wheatgrass. Forbs comprised relative cover of 24.0%. Forbs were dominated by yellow <br />sweetclover and sainfoin. The most abundant weed species, Bull thistle and field bindweed, <br />together comprised 2.4% relative cover. <br />The 63.6% total vegetative cover exceeded the 36% success criterion; therefore, in accordance with <br />Part 4 of the Guideline Reaardinz Selected Coal Mine Bond Release Issues, a statistical analysis of <br />the sample data was not necessary. The sample data from the Carbon Junction Mine indicate the <br />reclaimed areas have a diverse assemblage of grasses and forbs. No large bare areas or weed <br />problems were found. The grasses and forbs on the site are a self-sustaining mix of vegetation that <br />provides long-term erosional stability in support of the postming land uses. The vegetation appears <br />7