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The ARR reports that patches of Canada thistle were sprayed with herbicide. Please define when and with what specific herbicide spraying was conducted with. The post-mining land use is rangeland. The revegetation success standards are 25% vegetative cover. Perennial grass species shall comprise greater than or equal to 60% of the cover, a minimum of 10% cover should be provided by perennial forb species, and at lease 5% of the cover shall be attributable to shrub species. Grass species will need to make up a minimum of 15% total cover in order for that portion of the diversity standard to be achieved. The 1998 vegetation sampling data indicates that on both the topsoiled and non-topsoiled areas [he cover standard has been exceeded. The non-topsoiled area measured 32.67% vegetative cover. The topsoiled azea was measured at 33.53% vegetative cover. Distribution of the plants makes a definitive impact on the two areas. The topsoiled azea has a greater percentage of grass species (16% relative cover) and a more even distribution of the established plants. Few erosion rills are observed are observed on the topsoiled area. The vegetation on the non-topsoiled area is dominated (90% relative cover) by one species, Cicer milkvetch. Bare ground measured in the non-topsoiled area exceeds that of the topsoiled azea by 19 % relative difference (43.2% vs. 36.33% respectively.) Standazd deviation calculations were not submitted with the ARR submittal. The growth habit of Cicer milkvetch is clumped, tap-rooted deciduous species. Considerable space exists between each Cicer plant. The non-topsoiled area tends to form numerous rills throughout the azea. This rilling is not noted to the same extent on the topsoiled slopes. On the non-topsoiled areas vegetation is not established suitable to control erosion. The Division is concerned that although Cicer milkvetch is a desirable reclamation species, it also tends to be a short lived perennial. It's deciduous nature provides little ground cover once the leaves have fallen during late fall, winter and early spring months. The tap-rooted habit provides little soil cohesion compared to the mat forming fibrous root systems of sod forming grass species. Review of the success standards indicates that the desired vegetation will be grass dominated. Review of the sampling data does not indicate that perennial grass species are establishing on the non-topsoiled area (2.2% total vegetation cover is attributable to perennial grasses on the non-topsoiled area.) The Division questions why Energy Fuels states that "the predominance of grass cover on the topsoiled sites has been extensively criticized in numerous regulatory settings, as precluding realizing goals of achieving a diverse and shrub dominated plant cover." The revegetation success standard at this site has been drafred to heavily favor a grass dominated community with perennial forbs and shrubs as minor components. The post- mining land-use and success standazds do not encourage a diverse or shrub dominated vegetation community. While the operator's statement may apply to other areas of the state where heavy grass dominated rangeland has not been the desired post-mining community, the opposite is the goal for successful reclamation at the Raton Creek Mine. ,i ',.