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Sample Adequacy Sample adequacy calculations were completed for vegetative cover and productivity. The following formula, accepted by the CDMG, was used for these calculations: z z Nmin= t S (d Xbar)2 Where: Nm;n= minimum sample size t= the "T" distribution value at the 90% confidence level s= sample standard deviation s2= sample variance d= percent acceptable deviation from the mean (10%) Xba,= sample mean Sample adequacy was achieved for vegetation cover but not for vegetative productivity. Minimum sample size (Nm;°) is reported on Tables 2 and 3. Statistical Analysis Evaluation of revegetation establishment and success was accomplished through a comparison of the reclaimed area mean and the approved permit revegetation success standards, permit page 2.05.4(2)(e)-4. A "student's t-test" was used for the statistical comparison. This analysis is consistent with the recommendations of the Colorado Division of Minerals and Geology in the April 18, 1995 Guideline regarding selected Coal Mine Bond Release Issues. The reverse null hypothesis was used to demonstrate success for production. Plant species relative cover derived from quantitative total cover information provided the basis for assessment of species composition. III. Results Revegetation Success Standards Cover: 41 Production: 514 Ibs/acre (air dry weight) Shrub Density: No shrub density requirement Species Diversity: At least three perennial grass species, each contributing at least 3%, but not greater than 60% relative cover. At least one of these species will be a warm season grass and at least one shall be a cool season grass. Cover Sixteen plant species were encountered during the 2004 cover sampling. Mean live vegetative cover calculated from the data collected is 37.73% (Table 2). This value is less than the revegetation standard of 41%. Ninety percent of the cover standard is 36.9%. Evaluation of