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further assumed that these sample points would be located within each BRB without regard to the separately delineated shrub density category areas. Shrub density sample points will need to be differentiated on the mapping from coverlproduction/species density sample points. Some clarification is warranted to confirm the intent. 7. Sample Adequacy Determination Minimum sample sizes and sample adequacy formulas for cover and production are specified on page 8. Sample adequacy for woody plant density is addressed on page 15. Sample adequacy for species density evaluation (for diversity success testing) is not specifically addressed (other than reference to "assessment in the usual (Appendix A) manner"). Reference area and BRB sample adequacy assessment for species density should be clearly described. 8. Hypothesis Testing Approaches a) Cover and Production i) The standard null hypotheses for cover and herbaceous production success testing are stated on page 8. Our understanding is that the testing would only (necessarily) be applied in BRB-3. The acreage weighting factor (83/17) based on the entire permit area is an acceptable approach, given the distribution of pre-mining vegetation types at Seneca II. An alternative approach would be to base the weighting factor on the areal percentage occupied by each of the two pre-mine vegetation types within the perimeter of the individual bond release block. ii) The Seneca II approved permit indicates that the cover success standard would be based on weighted reference area herbaceous cover, multiplied by a factor of 2 (see pages 13-35 and 13- 36 of the permit document). It is not clear whether "first hit" cover or a "multiple hit" cover approach was intended in the permit narrative. The 3/8105 draft proposal indicates on page 8, that total (weighted) reference area vegetation cover would comprise the cover standard, rather than adjusted (2x) herbaceous cover. The proposal does not specify whether "first hit" or "multiple hit" cover would be employed. These specific details need to be clarified. If a cover standard different than the standard specified in the approved permit is proposed, it will need to be described and justified in the technical revision application. iii) On page 9 and 10, "herbaceous cover' is mentioned as the cover success criteria, which differs from the hypothesis statement on page 8. Clarification is necessary. iv) On page 9 and 10, "reverse null" testing approaches, and the conditions under which they would be applied for cover and production are addressed. Note that non-parametric test approaches (including the Mann-Whitney test referenced) are not approved under the DMG 2003 proposed rules revisions for cover and production, and reference to use of the Mann- Whitney or other non-parametric approaches for cover and production should be withdrawn. The reverse null t-test described is an acceptable approach, and sample adequacy is not required in the BRB for reverse null testing, if 30 sample observations are obtained. However, note that, in order for gone-sample t-test for cover or production to be valid (even under the reverse null scenario), sample adeguacv does need to be achieved in the reference area. If sample adequacy is not achieved in the BRB or in the reference area, but 30 sample observations are taken iri each area, atwo-sample reverse null t-test would be a valid approach. Two-sample t-test procedures are somewhat more complicated than one-sample test procedures. These details regarding sample size and testing procedures should be clarified.