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t = The (a =.10) t -table value for a 1 tail t -test, n -1 degrees of freedom (infinite degrees of freedom may be used if n >30) n = Sample size 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 c S- x Where: z = Reclaimed Area Sample Mean Q = 90 percent of (the weighted) Standard S = Standard error of mean [ s / v ] S = Sample standard deviation n = Sample size t� = Calculated t value t = Table t value The null hypothesis being tested is that the reclaimed area mean (g) is greater than or equal . to 90 percent of the standard, stated as H p >_ Q. If t 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 = — Q c S- x Where: Y = Reclaimed Area Sample Mean Q = 90 percent of Standard S = Standard error of mean [ s l v n ] S = Sample standard deviation n = Sample size t, = Calculated t value 4 = Table t value PR -02 2.05.4 -5 06110