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These data are included only to document historic trends and not in any way to satisfy any of the <br />required bond release vegetation sampling requirements. <br />Statistical Analysis of Data. As required by the Division's regulations, it is not necessary to <br />achieve sample adequacy for reclamation monitoring corresponding to the Phase III bond release <br />sampling efforts provided that the success standard has been achieved, the reverse null <br />hypothesis is used and a minimum number of transects had been sampled. If sample adequacy is <br />achieved, a minimum of a least 15 transects for cover and 30 transects for production and shrub <br />density must still be collected. Therefore, all of the data collected in this evaluation were <br />analyzed for sample adequacy in order to determine whether the Division's sample adequacy <br />requirements had been satisfied. The sample adequacy formula contained in the DRMS <br />regulations was used, wherein a precision of 0.10 was used for cover and production and 0.15 for <br />shrub density. <br />On the reclaimed and reference areas sampled, all of the field data were analyzed in terms of <br />"total plant cover" to determine whether sample adequacy was achieved prior to leaving the site <br />being sampled. On the reclamation blocks and reference areas sampled for production and shrub <br />density, a minimum of 30 samples were collected and the data analyzed before the reverse null <br />approach was applied to determine revegetation success. <br />According to previous written guidance received from Mr. Dan Mathews and Ms. Sandy Brown <br />of the DRMS, if sample adequacy is achieved on both the reclaimed and reference areas, and the <br />reclamation sample mean exceeds 90% of the standard, no statistical testing is required and <br />success is demonstrated by direct comparison. If sample adequacy is not achieved for one or <br />both of the reclaimed or reference areas sampled, but the reclaimed sample mean exceeds 90% <br />of the approved standard, the reverse null hypothesis can be used. <br />Results <br />Field Sampling Dates. Most of the data utilized in this evaluation were collected in during the <br />third and fourth weeks of July 2010. Subsequent evaluation of the data revealed that some <br />additional cover transects were needed, so the sampling was finished on September 15, 2010. At <br />the time of the field sampling, all of the plants were actively growing and it is believed that the <br />sampling was performed close to the period of optimum plant growth, when the plant cover and <br />production were near their peak. A total of 75 plant species were identified in the 67 cover <br />transects and 60 shrub density transects sampled in this evaluation. A list of all of the 93 plant <br />species encountered in the field sampling efforts in this evaluation is presented in Table 1, Kerr <br />Coal - Mine Plant Species List. <br />Sample Adequacy. A statistical summary and analysis of the data collected to characterize the <br />plant cover, production, and shrub density is presented in Table 2, Marr Mine - 2010 Statistical <br />Summary and Sample Adequacy Calculations. This comparison documents that a sufficient <br />number of samples were collected to describe the parameters of "total plant cover," production <br />