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Rule 4.15.7(3)(b) requires that the permittee "demonstrate statistically, to the satisfaction of the Division, that each proposed reference area is comparable to its equivalent area to be disturbed in terms of vegetative cover and herbaceous productivity..." To implement this requirement, Division policy as set forth in guideline documents, specifies that statistically adequate sampling of proposed disturbed areas and associated reference azeas be conducted within the same growing season, to minimize the effect of differing weather conditions on vegetative growth. Colowyo has not provided this statistical demonstration of comparability for the South Taylor project area, with respect to big sagebrush and mountain shrub community types. In the amended application, Colowyo is requesting that the Division approve the use of existing mountain shrub and sagebrush reference areas for the South Taylor project area that were established in 1980/1981, despite the Fact that the South Taylor project area and the existing reference areas were apparently never sampled during the same year. The baseline sampling of the project area that Colowyo is utilizing was conducted in 1984 by Harner Associates, but the existing Colowyo reference areas were not sampled as a part of that study. Limited sampling of the existing reference areas was conducted in 2005 by Cedaz Creek Associates, and more intensive sampling of the reference areas has been conducted in earlier years, but the South Taylor project area was not sampled in 2005, nor was it sampled in previous yeazs in conjunction with sampling of the existing reference areas. Colowyo has included a new section in the amended application, beginning on page R2-78, titled Justification for Reference Area Selection. Justifications (summarized) for using the existing sagebrush reference area are: • Better access than Harner 1985 South Taylor Reference Area (ST-SRA). • More extensive data base than ST-SRA. • Existing reference area (C-SRA) is a better "ecological target", because of higher perennial grass composition and lower mountain shrub composition in C-SRA and S.Taylor affected area compared to ST-SRA (based on 2005 C-RA Ref data and 1984 ST-RA data). • ST-SRA is transitional between big sagebrush and mountain shrub communities; C- SRA is a more representative sagebrush grassland. • ST-SRA cover and production levels significantly exceed South Taylor affected area cover and production levels, as well as other comparable sagebrush data sets from the area (various yeazs). Similar justifications are presented for use of the existing mountain shrub reference area, with the exception of the "better ecological target" argument. We have the following requests regarding the reference area proposal: a) Given the problem of the absence of a statistical demonstration of compazability between the South Taylor affected area and the existing reference azeas, and in