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Vegetation Type <br />Allowable Herbaceous <br />Cover on a first -hit basis* <br />% of Pre - mining Area <br />Mountain Brush <br />15.1 <br />83.0 <br />Sagebrush <br />44.7 <br />17.0 <br />generous estimate possible of the maximum true value of mean after the minimum fifteen samples had <br />been collected. <br />Assessment of BRB for Compliance with Phase II Performance Standards <br />Calculation of allowable herbaceous vegetation cover as well as sample adequacy is shown in in -text <br />tables summary tables above and detailed in Tables 1b, 2b and 2c. <br />Calculation of 90 percent of the cover performance standard appropriate for 2010 sampling is <br />demonstrated below and is based on the following information: <br />* Herbaceous cover adjusted by subtracting noxious weeds and annual/biennial plant cover in excess of 10% of the remainder. <br />2010 Mountain Brush Reference Area First -hit Allowable herbaceous cover X 2 = 30.2% <br />2010 Sagebrush Reference Area First -hit Allowable herbaceous cover X 2 = 89.5% <br />90 percent of the Cover Standard = 0.90 [0.83 X (30.2) + 0.17 X (89.4)] = 36.2% <br />Calculation of 90 percent of the cover performance standard appropriate for 2010 sampling is <br />demonstrated below. <br />Allowable herbaceous cover of the Seneca II bond release block tested for Phase II bond release (40.0 %) <br />exceeded 90% of the standard (36.2% allowable cover). The bond release block figure is the result of <br />subtracting tree, shrub and non - herbaceous cover (1.5 %) and noxious weed cover (0.95 %) and "excess <br />annual /biennial cover" (2.0 %) from the observed first -hit total vegetation cover of 44.4 %. <br />A t -test of the (reverse) null hypothesis that the 2010 Phase II BRB allowable cover does not exceed 90% <br />of the standard (i.e. is indistinguishable from it) is as follows: <br />t� = (40.0— 36.2) /(9.39 / sqrt 21) = 1.85 <br />Since critical t = 0.860 (one - tailed, alpha = 0.2, 20 df) and t, is greater than this critical value, the null <br />hypothesis (that the mean is indistinguishable from the standard) is rejected, and the alternative <br />hypothesis that the reclaimed area mean is indeed larger than the standard is accepted. Thus <br />reclamation success for Phase II bond release is demonstrated. <br />14 <br />