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10. BME provided amended narrative to describe the results of cheatgrass herbicide treatments <br />and remedial seeding conducted on Refuse Area 1 and adjacent Topsoil Stockpile 2/3 in <br />2000. Item Resolved. <br />11. BME provided amended language on revised pages V-53 and V-63 to reference new Rule <br />4.15.11, as requested. Item Resolved. <br />12. BME provided properly amended language on revised page V-64, to include updated <br />references to Rule sections pertaining to statistical testing for demonstrations of revegetation <br />success. Item Resolved. <br />13. BME provided requested clarifications specifying comparisons of perennial vegetative <br />cover and perennial herbaceous production for demonstrations of revegetation success, on <br />revised page V-61. Item Resolved. <br />14. DRMS had requested additional information regarding the paired sampling success <br />demonstration procedure approved in the application for various "small and linear features" <br />and drill sites, including sampling approach, sample size, and t-test details. BME addressed <br />the issues of concern in the narrative response to Item 14 in the TR-65 cover letter. <br />However, the information was not included in amended sections of the permit application. <br />In general, the procedural description, modified t-test formula and test statistic terms <br />presented in the letter appear to be appropriate and acceptable. <br />Clarification is requested regarding determination of adequate sample size, with respect to <br />paired sampling. Narrative indicates that minimum sample size would be determined in <br />accordance with Section 4.15.11(2) of the rules, and that both the reclaimed and reference <br />portions of the transects/quadrats would be subject to sample adequacy requirements. In <br />paired sampling, it is the difference values between each set of paired observations (the "D" <br />values) that provide the pertinent statistics for determinations of success. Because the <br />statistics used in the t-test for paired sampling are derived from the "D" values, the sample <br />variance and sample mean for "D" should also be substituted for the standard sample <br />variance and sample mean terms specified in the sample size adequacy formula listed in <br />Rule 4.15.11(2)(a). It is not clear from the amended text or supplemental narrative that the <br />sample adequacy formula would be properly modified with respect to paired sampling. We <br />also note that, to conform with regulation, the minimum number of paired observations <br />would need to be 15, in cases where the formula indicates a sample size smaller than 15. <br />Minimum required number of paired observations would be 30, in order to demonstrate <br />success using the "reverse null" t-test. <br />Please include the information on sampling procedures, statistics and formulas <br />relevant to paired sampling [including modified sample adequacy formula, minimum <br />sample sizes (minimum number of paired observations), and modified West formula] <br />in the amended permit application (either as expanded text or as an appendix or <br />attachment referenced in the text). <br />