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reference area] provides a far better example of the long-term desirable vegetation structure and composition that is more closely tied to the habitat requisites of Sage Grouse. Given the mobility of most wildlife taxa (including Sage Grouse), there is sufficient Mountain Shrub habitat within proximity to planned disturbances to meet a majority of perceived needs of other wildlife populations... The originally approved sagebrush reference area, established in 1981 within the original Colowyo permit area, will be utilized for this "targeted reference area" rather than a separate sagebrush reference area established in association with 1984 vegetation studies, located to the south of the South Taylor expansion area. Reasons for use of the original sagebrush reference area in preference to the 1984 reference area are set forth under Justification for Reference Area Selection-Sagebrush Reference Area, in Section 2.04. 10 of Volume 12. Originally, the woody plant density standard at the Colowyo Mine was set at 1,000 live stems per acre. Based on the reclamation practices at the Colowyo Mine, including thick topsoil replacement (18"+), the use of highly aggressive, competitive introduced grass species and wildlife foraging, the majority of the lands reclaimed prior to 2008 do not come close to meeting this standard of 1,000 live stems per acre. In consultation with the DOW, the woody plant density standard for the pre-2009 areas was revised with the approval of TR-72. The woody plant density standard at the Colowyo Mine will be applied to the three distinct reclaimed areas: the pre-2009 area, the 2009-forward grassland area and the 2009-forward sagebrush steppe area. The standard for these areas is as follows: The woody plant density success standard for the pre-2009 reclamation at the Colowyo Mine will be 150 live stems per acre on at least 3% of the reclaimed surface. No woody plant density success standard will be applied to the 2009-forward grassland area reclamation at the Colowyo Mine. The woody plant density success standard for the 2009-forward sagebrush steppe areas at the Colowyo Mine is further broken into two distinct areas. These two areas are the "core" area and the "ecotonal" area. Together these areas must comprise a minimum of 450 acres of the post-2009 reclamation at the Colowyo Mine. The woody plant density standard for the "core" area will be 375 live stems per acre. The "core" area must comprise at least 50% of the total sagebrush steppe area (a minimum of 225 acres). The woody plant density standard for the "ecotonal" area will be 200 live stems per acre. Additionally, Big Sagebrush must account for at least 50% of all countable live stems and fourwing saltbush is limited to 20% or less of the total countable live stems for both the "core" and "ecotonal" areas. Pre-mine inventory and reference area woody plant density measurements were taken along three-foot-wide belts located along 100-foot-long transects. Similar methodology should be Proposed Decision and Findings of Compliance 14 September 2009 Permit Renewal 05 Page 62