2012-06-20_PERMIT FILE - C2010089A (7)

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Upon comparing the proposed Big Sagebrush disturbance areas with the existing Dry land Pasture Reference area, it can be determined that the calculated t value for total plant cover and forage production were determined to be equal 3.5796 and 2.8988, respectively. The corresponding t were determined to equal 2.048 and 1.986, respectively. Since both the t values for both plant cover and forage production, exceed the corresponding t values, it can be concluded that the total plant cover and forage production values between these two sites is statistically different. A major reason for these differences is largely attributable to the fact that upon comparison of Appendix Table 2.04.10 -6, Big Sagebrush - Plant Cover with Appendix Table 2.04.10 -24, Dryland Pasture Reference Area - Plant Cover, it can be readily observed that the total plant cover value is 26.60 percent for Big Sagebrush and 16.39 percent for the Dryland Pasture Reference Area. Shrubs and subshrubs contributed 12.47 percent of the total plant cover for the Big Sagebrush and only 8.00 percent of the total cover for the Dryland Pasture Reference Area. Annuals and biennials contributed 8.40 percent of the total cover for Big Sagebrush type and only 0.56 of the total cover for the Dryland Pasture Reference Area. Unfortunately this comparison of total cover does not take into consideration the requirements of Section 4.15.7, which requires that annuals and noxious weeds cannot be counted toward the final revegetation success. Applying the same logic to the pre - mining comparison, means that if the DRMS requires that annual and noxious weed cover is applied to the pre - mining comparison, it would require that lands must be reclaimed to a lower ecological condition, which is contrary to the regulations that require that all lands be reclaimed to a higher or more productive condition. The Division's Guidelines for Compliance with Land Use and Vegetation Requirements for Coal Mining, acknowledges this contradiction on page 11 wherein it states that in vegetation types dominated by "dense woody cover and a weak herbaceous understory or poor condition rangeland dominated by weedy annuals or other undesirable species a `modified' reference area ... might be appropriate." Upon subtracting the annual and weedy species component from the Big Sagebrush predisturbance areas, the "allowable plant cover" value for this vegetation type can be determined to equal 18.60 percent (Appendix Table 2.04.10 -6, Big Sagebrush - Plant Cover). Upon comparing the "total allowable cover on the proposed Big Sagebrush predisturbance areas, with the total plant cover value on the existing Dryland Pasture Reference Area, which contains significantly fewer annuals and no noxious weeds, the calculated t value for "allowable plant cover" was determined to be equal 0.4287, which means that since the t value is lower than the t value of 2.042, it can be concluded that the Big Sagebrush predisturbance area and the Dryland Pasture Reference Area are equal in terms of "allowable plant cover." This comparison and accompanying discussion, documents that it is inappropriate to compare these areas with respect to total plant cover since it involves comparing a very poor ecological condition site to one in higher condition which is contrary to the DRMS regulations, which Section 2.04.10 Page 31 November 2011