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n =Sample size t~ = Calculated t value t, = Table t value The null hypothesis being tested was that the bond release block mean (µ) was greater than or . equal to 90% of the standard, stated as H°: µ _> Q. If t° was less than or equal to the 1-tailed t table value for alpha error probability of 0.10, at (n-1) degrees of freedom (infinite degrees of freedom may be used if n>30), then Ho was not rejected, and revegetation was deemed successful for the parameter tested. If: Sample adequacy for herbaceous cover has not been achieved in Phase II Bond Release Area and a total of 30 or more samples have been taken, and the means for total allowable herbaceous foliar cover in the Phase II Bond Release Area exceed 90% of the reference area- derived standard, then the hypothesis of reclamation success is 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 (CDMG rules, 4.15.11 (2)(c)): _ xQ t` S- s Where: x =Bond Release Block Sample Mean Q = 90% of Standard g_ =Standard error of mean [ s 1 ~] S =Sample standard deviation n =Sample size tc = Calculated t value tt = Table t value I • The null hypothesis being tested would be that the bond release block mean (µ) was less than or equal to 90% of the standard, stated as H°: µ <_ Q. If tc was greater than the 1-tailed t table value for alpha error probability of .20, with (n-1) degrees of freedom (infinite degrees of freedom may be used if n>30), then Ho was rejected, and revegetation would be deemed successful. For the above (one-sample) t-test, it is necessary to have achieved sample adequacy in the reference area sampling. Were adequacy NOT to have been achieved in the reference areas, then the more complex calculations associated with atwo-sample t-test (CDMG rules) are undertaken. 6