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If: Sample adequacy for herbaceous cover or production has not been achieved in BRB~ and a <br />total of 30 or more samples have been taken, and the means for total herbaceous foliar cover or <br />herbaceous production in the BRB reclaimed area exceed 90% of the reference area-derived <br />standard, then the hypothesis of reclamation success is tested under the conditions a °reverse <br />null" approach using a parametric test of the °reverse null° hypothesis. This would be conducted <br />using the following expression (CDMG 2003 proposed rules revisions, 4.15.11 (2)(c)): <br />t -X_Q <br />` S- <br />x <br />Wh@re: <br />x =Bond Release Block Sample Mean <br />Q = 90% of Standard r~ <br />S_ =Standard error of mean [ s / y n ] <br />x <br />S =Sample standard deviation <br />n =Sample size <br />k = Calculated t value <br />Q = Table t value <br />The null hypothesis being tested is that the bond release block mean (µ) is less than or equal to <br />90% of the standard, stated as H°: µ s Q. If k is greater than the 1-tailed t table value for alpha <br />error probability of .20, with (n-1) degrees of freedom (infinite degrees of freedom may be used if <br />n>30), then H° is rejected, and revegetation is deemed successful. <br />For the above (one-sample) t-test, it is necessary to have achieved sample adequaq in the <br />reference area sampling. Were adequacy NOT to have been achieved in the reference areas, <br />then the more complex calculations associated with a two-sample t-test (CDMG 2003 proposed <br />rules revisions) are undertaken. <br />Cover will be addressed in hypothesis testing as percent absolute first hit herbaceous vegetation <br />cover as adjusted for excessive contribution by annual /biennial species (CDMG 1995, <br />Guidelines Regarding Selected Coal Mine Bond Release Issues, 1 (I~A(4)). Cover from <br />reclaimed area samples will be addressed as total percent first hit herbaceous cover. Cover from <br />8 <br />