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initial paragraph below Table 1 could be replaced with a statement referring the reader to <br />the B10- Logic, Inc. report in Appendix B, "2007 -20081 Vegetation Studies for Phase 3 Bond <br />release... ", for a detailed presentation of data, sampling methods, statistical demonstrations <br />of success, and summary discussion of study results. Please reprise the narrative on the as <br />appropriate. <br />In accordance with the bond release guideline (page 11 and 1 , Items 1 and 4), please <br />provide a narrative summary of the reclamation and management history of the parcels <br />included in the Phase III release request, including narrative regarding achievement of <br />the approved post - mining land uses. In addition, please provide narrative addressing <br />the "quality standard" of the approved permit for irrigated pasture (i.e. that ''at least <br />75% of the relative production will be comprised of seeded species or species of <br />comparable quality as livestock forage). Because production data was not collected b <br />species, conformance with this requirement may need to be based in part on inference <br />from the vegetation relative cover data. <br />9. Please provide corer summary tables, to supplement the spreadsheet Tables A l and <br />A, in the data section of the Vegetation Report (refer to Item B, above, for detailed <br />explanation of the request). <br />10. 2007 IP production success demonstration is presented on pages 11 and 12 of the Phase <br />Vegetation Report. Summary information including statistics is presented in Table 2, <br />page 11. Sample Data is presented in Table A (reference area) and Table A4 (reclaimed <br />area). The reclaimed area production sample mean exceeded the reference area <br />sample mean by a wide margin, and because sample adequacy was not demonstrated in <br />the reference area, a -- sample reverse null t -test was properly selected to demonstrate <br />that the difference was statistically significant (i.e. that the reclaimed area true mean <br />exceeds the reference area true mean). The various formulas associated with the t --test <br />demonstration are presented in their correct and proper fora in equations 4, 5. and , <br />on pages 8 and 9 of the report. <br />In the calculations however, there were a couple errors, one minor, and one more <br />significant. <br />a) In Table 2, the Table t- statistic used for comparison to the calculated t- statistic is the <br />t value for an alpha error probability of 0.1. This value is more stringent than the <br />alpha error probability level of 0.2 allowed by Pule 4,1.11()(), and specified in <br />Equation 6,. on page 9 of the Vegetation Report. This is a minor error, which would <br />work to the disadvantage of the operator, <br />b) The more significant error is that, apparently, a parenthesis was inadvertently <br />omitted from the t -test formula of Equation 6 when it was entered into Excel as a <br />formula. This resulted in an erroneously high value for the calculated t- statistic <br />(6,705.604), as reported in Table 2. The Division independently entered the data <br />and ran the statistical tests for the 2007 1P production data in Excel., with the <br />spreadsheet data . Our results are presented in Attachment 2 to this memorandum. <br />The calculated t- statistic we obtained was 4.7. Since 4. 7 is greater than the table t- <br />stati ti of 0.847 (for alpha error probability of 0.2) the conclusion remains the <br />5 <br />