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substantially replaced by recent regulation amendments, specifically new Rule 4.15.11. Please amend the section to clarify sampling plans and statistical methods for future demonstrations of revegetation success, and to ensure that sampling plans and statistical formulas comply with applicable provisions of 4.15.11. New Horizon 2 Site Description and Land Use Information (Section 2.04.3) 6. Rule 2.04.3(2)(a) requires a map and supporting narrative describing the pre-mining land uses in the permit area, in accordance with the land use categories established in the land use definition in Rule 1.04. Narrative and tables in Section 2.04,3 of the application, as well as Map 2.04.10-1 and narrative in the Vegetation and Land Use Overview of Section 2.04.10 seem to use vegetation types and land use categories somewhat interchangeably, which leads to some confusion. Based on our interpretation of the permit information and site observations, primary pre- mine land uses pursuant to the land use categories in Rule 1.04 (71) would include "Cropland", "Pastureland", and "Rangeland". Vegetation types within the Cropland land use category would include irrigated grain crops and irrigated hayland (alfalfa hay and grass hay sub-types). Vegetation types within the Pastureland land use category would include irrigated and dryland forage plantings (e.g. irrigated pasture and dryland pasture). Some lands currently designated "irrigated pastureland" in the permit, may best fit in the "Cropland" land use category, while other areas with the same current designation might best fit the "Pastureland" land use category. Proper designation would depend on the level of management, and whether the land is used for hay production on a relatively regular basis, or only "occasionally', if at all. The "Rangeland" land use category would include the various sagebrush vegetation types and the pinyon/juniper community. Small weedy waste areas that have developed at field corners, low spots, stock concentration areas, etc., would logically be included within the dominant adjacent land use category. Similarly, the swale vegetation type that has developed within the Pastureland and Cropland land use areas, should be included within the respective land use category (Pastureland or Cropland). Please submit a premining land use map, delineating land use categories in accordance with Rule 1.04(71), and corresponding amended narrative and tables for inclusion in Section 2.04.3. New Horizon 2 Vegetation Information (Section 2.04.101 On page 2.04.10-89, there is discussion of the fact that a new dryland pasture reference area was established in 2005, immediately adjacent to the former dryland pasture/rangeland {combined) reference area, because of the number of shrubs in the combined reference area. Attachment 2.04.10-3 presents the results of the 2005 sampling of the new dryland pasture reference area and comparison of the 2005 data for the new area to the 1999 data for the combined reference area. The data indicate that shrub cover was somewhat higher in the combined area compared to the new dryland reference area, but in both areas shrub cover was relatively low (1.2% and 3.3%, respectively}. The shrub cover may have increased in the combined area since 1999, but this was not documented. Total perennial cover and herbaceous production levels for the two areas were quite similar between sampling years, however perennial (orbs were the dominant life form in the new dryland area in 2005, whereas perennial grasses were dominant in the combined reference area in 1999. Perennial grass production in the combined reference area in 1999 was 424 pounds per acre, compared to 32.7 pounds per acre in the new reference area in 2005. It is not clear whether the reversal with respect to relative dominance by grasses (1999 combined) and forbs (2005 new dryland)