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STATISTICAL EVALUATION OF REVEGETATION COVER SAMPLING The collection of statistically adequate data for the parameter of vegetation cover allows the statistical evaluation for compliance with the revegetation success criteria of the mining and reclamation permit. The revegetation success criterion for cover is 70 percent live aerial cover. The correct evaluation of the revegetation samples from the 1992 survey is accomplished through the use of aone-tailed hypothesis concerning the mean (Zar, 1974). In this case, the evaluation tests whether the sample cover mean from the revegetated areas is statistically equal to 90 percent of the standard with 90 percent statistical confidence. The hypotheses to be tested are: Ho:µ>0.9C Ha:µ<0.9C where: C= the revegetation cover standard of 70% live aerial vegetation cover The test statistic to be employed is the one-tailed t-test (Zaz, 1474). The equation for the test is as follows: t = Xbaz C where: Sx = S(sgrt[n] Sx where: Xbar= the sample mean C =the cover standard Sx =the standard error of the mean n =the number of samples taken The values for the revegetation cover sampling in 1992 (Hayes, 1992) are: Xbar= 61.2 C = 0.9x(70.0) Sx = 2.42 n = ]7 The t test equation with the sample cover data becomes: t = [b1.2-(0.9)x(70)]/2.42 = 0.744 The critical value of the t statistic for 90'% confidence, one-tailed test, with 16 degrees of freedom is 1.337. Since the calculated t value is less than the critical value, the original hypothesis (Ho :population mean (µ) > 0.9 C) is not rejected, The statistical conclusion is that the areas sampled meet the revegetation success criterion for cover. These areas have live aerial vegetation cover greater or equal to 90 Yb of the 70 `% aerial vegetation cover with 40 9'o statistical confidence.