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The herbaceous cover on the reclaimed rangeland area exceeded the herbaceous cover measured on the grassland reference area. The cover is successful on this portion of the reclamation for phase II bond release. The reclaimed pastureland was compared to the AVF reference area. Herbaceous productivity is the applicable success parameter for the reclaimed pastureland areas (reclaimed ponds 003 and 005). The herbaceous biomass measured on the reclaimed pasture was less than the herbaceous biomass measured on the AVF reference area. However, herbaceous biomass measured on the reclaimed pasture is greater than ninety percent of herbaceous biomass on the AVF reference area. Therefore, the adequacy formula described by Kupper and Hafner (Guideline Regarding Selected Coal Mine Bond Release Issues, April 18, 1995) was used to determine minimum sample size. // ~la +lb~Zls~ Kupper and Hafner Sample Adequacy: N m , (d~- Using this formula, the minimum number of transects needed on the pasture reference area was 7.14. Basin Resources collected 12 productivity transects on the reclaimed pasture. Herbaceous productivity data collected on [he reclaimed pasture and [he AVF reference area is shown in [he following table: Herb. Biomass Std. Deviation #transects measured Min. #transects talc. AVF reference area 191 1.70 lbs./ac. 371.48 10 7.22 Reclaimed asture 1820.1216s./ac. 236.36 12 7.14 Since the herbaceous biomass on the reclaimed area was less than the mean herbaceous biomass of the reference area, but greater than ninety percent of the reference area biomass, aone-sample T-test was calculated to assure that the reclaimed area met "90% of the production as determined from the reference area with 90% statistical confidence." (Rule 4.15.8(4)(a)). This test found that the reclaimed area production was greater than 90% of the production measured on the reference area at a 90% confidence interval. Vegetation establishment on the reclaimed pasture is successful for the requirements of phase 11 bond release. Species diversity is evaluated at the time of phase II bond release, although it is not a requirement to achieve phase II success. Species diversity is evaluated from vegetation sampling data submitted at this time to assure that the reclaimed community is progressing toward the species diversity standard required at final bond release. Golden Eagle Mines diversity standard requires a minimum of two cool season grasses, two warm season gasses and one forb. No one species shall exceed 60% relative cover and each species shall comprise a minimum of 5% relative comer. No diversity standard shall apply on the reclaimed pasture. Ten perennial grass species were present on [he reclaimed rangeland. Only one cool season species, Bromopsi.s inermis, exceeded 5% relative cover. Six species exceeded 3% relative cover, with two of those species belonging to warm season grass category. No one species exceeded 60% relative cover. Ten perennial forb species were measured on the reclaimed area, with three species exceeding the 5% relative cover and none exceeding the 60% relative cover. Based on the June 2000 vegetation sampling, the reclaimed area is progressing toward the species diversity standard (permit page 2.05-20. The Division verified topsoil replacement depth during and inspection on July 22, 1997. Three topsoil holes were dug at the reclaimed pond 005 location. Holes were dug util ground became too hard to dig further. Hole profile was inspected for color and texture. Organic material had been incorporated into the profile at a depth of 4 to 6 inches. Reclaimed Pond 005 Measured to soil thickness Re wired to soil thickness Hole 1 12 inches 12 inches Hole 2 1 1 inches 12 inches Hole 3 13 inches 12 inches Topsoil replacement thickness was acceptable a[ the reclaimed pond 005 area.