2011-02-04_PERMIT FILE - C1980005 (2)

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• If the mean all hit herbaceous cover or herbaceous production of an adequate sample from the reclaimed area is less than 90 percent of the cover standard, then a one-sample t-test will be made in the following form to test the hypothesis of reclamation success for cover (CDRMS Coal Section, 4.15.11 (2)(b)): t -Q-x S- X Where: x = Reclaimed Area Sample Mean Q = 90 percent of (the weighted) Standard Sr = Standard error of mean [ s l,rn ) S = Sample standard deviation n = Sample size t, = Calculated t value tt = Table t value The null hypothesis being tested is that the reclaimed area mean (µ) is greater than or equal to 90 percent of the standard, stated as Ho: µ >_ Q. If tc is less than or equal to the one-tailed t table value for alpha error probability of .10, at (n-1) degrees of freedom (infinite degrees of freedom may be used if n>30), then Ho is not rejected, and revegetation is deemed • successful for the param tested. If sample adequacy for all hit herbaceous cover or herbaceous production has not been achieved after a minimum of 30 samples in the reclaimed area _and the means for all hit herbaceous foliar cover or herbaceous production exceed 90 percent of the reference area- derived standard, then the hypothesis of reclamation success will be tested under the conditions a "reverse null" approach using a parametric test of the "reverse null" hypothesis. This would be conducted using the following expression (CDRMS Coal Section, 4.15.11 (2)(c)): t = x-Q S- X Where: x = Reclaimed Area Sample Mean Q = 90 percent of Standard SX = Standard error of mean [ s / -\Fn ] S = Sample standard deviation n = Sample size t, = Calculated t value tt = Table t value The null hypothesis being tested is that the reclaimed area mean (µ) is less than or equal to • 90 percent of the standard, stated as Ho: µ <- Q. If tc is greater than the one-tailed t table PR-02 2.05.4-5 10/10