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Sample Adequacy A summary of sample adequacy calculations for the parameters of cover, herbaceous production, and woody plant density is presented in Table 16 (Appendix 1). As can be seen in this table, the data sets for cover for the two reclamation areas (and the Phase II Bond release test area) as well as the five sampled extended reference areas all achieved sample adequacy. Production data collected in the 2002 reclamation achieved sample adequacy, but the 2004 data did not (Table 16). Note that no formal testing for Phase III bond release that would involve herbaceous production were undertaken this year, so achievement of adequacy was not at issue. As would be expected, minimum sample sizes for background area shrub sampling far exceeded those taken. L_J I Phase 11 Bond Release Hypothesis Testing Average allowable cover observed in the Phase II bond release areas sampled in 2006 was 28.5%. The upper limit of the 90% confidence interval associated with the area sampled to produce cover data applicable to a potential Phase II bond release application, which had minimized herbaceous seeding to enhance shrub establishment, did not meet 90% of the standard (37.4% allowable cover). The figure for allowable cover in this Phase II Area (28.5%) is the result of subtracting all- hit shrub cover (0.3%) and perennial noxious weed cover (0.95%) and "excess annual/biennial cover' (5.0% which includes the non-allowable cover by the noxious species houndstongue and bull thistle) from the observed all-hit total vegetation cover of 34.7%. A t-test of the assertion that the 2006 Yoast Phase II area allowable cover is indistinguishable from 90% of the standard is as follows: tc=(37.4-28.5)/(7.2/sgrt20)=5.52 Since critical t = 1.319 (one-tailed, alpha = 0.1, 23 df) and tc is greater than this critical value, reclamation success for Phase II is not demonstrated. 17