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4. Production and woody plant density methods described in Sections 2.3 and 2.4 of <br />the report aze generally acceptable, and the methods differ from those described in <br />the approved permit in relatively minor details. One item of note however, is that <br />the operator indicates in the narrative of Section 2.4 that subshrubs and succulents <br />were included in the woody plant density counts. In actuality, these life forms do <br />not appeaz to have been encountered in the sample quadrats. Division guidelines <br />specify that subshrubs be included in cover and production data, and not included <br />as woody plants unless specific justification is provided. Guidelines do not <br />specifically address succulents, but typical practice has been to include such <br />species in cover data, but not woody plant density data. The current permit does <br />not specify that subshmbs or succulents would be counted towazd the woody plant <br />density success standard. Unless specific justification is provided and <br />approved, subshrubs and succulents should not be counted as woody plants <br />for success demonstration. <br />5. Section 2.5 addresses Sample Adequacy Determinations and Testing for Success. <br />We have the following comments/concerns: <br />a) The sample adequacy formula listed after the first paragraph on page 9 (the <br />simpler of the two formulas) is acceptable under the "standazd null framework" <br />whether statistical testing is called for or not (see the Division's recently approved <br />program amendment submittal, Rule Section 4.15.11). The second formula listed <br />is not required. <br />b) Reference to a maximum sample size of 35, on page 9 paragraph 1 is <br />inappropriate and should be withdrawn. Sample adequacy using the specified <br />formula must be demonstrated for success demonstration under the "standazd <br />null" framework. Alternatively, if success demonstration is to be made under the <br />"reverse null" framework, a minimum sample size of 30 is required within the <br />reclaimed area, but reclaimed azea sample adequacy demonstration is not <br />required. If aone-sample, reverse null t-test is used to demonstrate that the <br />reclaimed area population mean exceeds the reference azea sample mean, sample <br />adeauacy does need to be demonstrated in the reference azea. If sample adequacy <br />is not demonstrated for the reference azea, atwo-sample t-test, rather than aone- <br />sample t-test can be employed, if a minimum sample size of 30 is obtained in the <br />reference azea, as well as the reclaimed azea. The two sample reverse null t-test is <br />used to demonstrate that the reclaimed azea population mean exceeds the <br />reference azea population mean, at the 90% level of statistical confidence. Based <br />on the relatively high variances and resulting large sample sizes indicated for <br />herbaceous production estimates in the reference areas, the two-sample, <br />reverse null t-test (with a minimum sample size of 30) may be warranted for <br />bond release sampling. <br />c) Anon-statistical direct comparison sample approach is acceptable for woody <br />plant density, if a sample size of 75 is obtained (see proposed Rule <br />4.15.11(3)(b)(i) of the program amendment. This might be considered as an <br />