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2 nmi°- t S - (d Xbar~2 where nm;° =minimum sample size t =the "T" distribution value at the 90% confidence level s =sample standard deviation sZ =sample variance d =percent acceptable deviation from the mean (10%) Xbar =sample mean Sample adequacy was achieved for the vegetation cover parameter. Twenty cover transects were initially sampled. Minimum sample size was 11 as reported on Table 2. Production data was analyzed using the reverse null. The reclaimed area sample mean was greater than 90 percent of the standard, but sample adequacy was not demonstrated using the above formula, therefore success was demonstrated by use of the "reverse" null hypothesis. Under the reverse null approach, a one sided t-test with alpha error probability of 0.20, can be used to demonstrate that the reclaimed area mean is greater than 90 percent of the relevant success standard with 80 percent statistical confidence. The basic assumption, or null hypothesis, is that the reclaimed area mean is less than or equal to 90 percent of the standard. If the null hypothesis of equality is rejected by the test, then reclamation is considered successful for production. A minimum sample size of thirty is required. The general form of the "reverse null" t-test is: XQ rc S'- s Where: x =Bond Release Block Sample Mean Q = 90% of Standard S_ =Standard error of mean [ s l ~ ] x S =Sample standard deviation n =Sample size k = Calculated t value t, = Table t value The null hypothesis being tested is that the bond release block mean (µ) is less than or equal to 90% of the standard, stated as H°: µ <_ Q. If k is greater than the 1-tailed t table value for alpha error probability of .20, with (n-1) degrees of freedom (infinite degrees of freedom maybe used if n>30), then Ho is rejected, and revegetation is deemed successful.