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achieved) of the original SL-02 application submittal, states that "the enclosed vegetation <br />study, ..shows the reclaimed nine site has better plant cover than the undisturbed adjacent areas <br />and the reference areas. Therefore, vegetation on the reclaimed mine site meets the approved <br />success standard for cover and supports the approved postmining land use of rangeland an <br />w ildlife habitat ". <br />The CCA vegetation report does contain information indicating that reclaimed area cover <br />w ithin a major portion of the site (Mine Area 1 is likely to meet or exceed the reference area <br />cover success standard. Ho the Division finds that the report does not provide (nor does <br />it purport to provide) a statistically valid demonstration of vegetation cover success, which is <br />required for Phase 11 Bond release approval. This finding is based on the following reasons: <br />a Based on vegetation Map 1 included in the CCA report, the revegetation "sarnple <br />universe", was limited to the main portion of Miring Area #1, and did not include <br />Mining Area #3, or the three small ancillary facility areas located south of the mining <br />areas; <br />b The CCA report includes narrative, charts and tables which show the likelihood that <br />cover success was achieved within the sampled reclamation area, but the report <br />describes the sampling as "monitoring in the interest of ascertaining progress.. ,'�, and <br />notes that sample size was restricted "due to managerial nature of collected data ". The <br />report does not state or imply that the sampling was conducted to provide statistically <br />valid data for bond release demonstration. <br />C) Sample adequacy was evaluated for the one reclaimed unit and various reference area <br />units "for informational purposes ". Minimum sample size of 15 was not achieved for <br />either of the to separate sagebrush reference areas or the split grassland reference area, <br />and tra.nsects were not proportionally allocated within the split grassland reference area. <br />Statistical sample adequacy was not achieved in either of the sagebrush reference areas, <br />and was not evaluated for the grassland reference areas combined as would be required <br />for bond release success demonstration). <br />d Chart 3 "Success Comparison..." shows the likelihood that the sampled reclamation <br />unit would easily meet the reference area cover standard. However, a valid statistical <br />demonstration that the cover standard was achieved in the sampled reclaimed unit was <br />not made, because sample size within the reference areas was insufficient. Further, the <br />CCA. report did not include a comparison of reclaimed area cover mean to % of) <br />acreage weighted reference area cover mean, as would be required to emon trat <br />success for phase 11 bond release. <br />For the various reasons listed here above, the Division requests that the operator submit a <br />request to formally withdraw the SL- Phase 11 bond release application. <br />2. The CCA vegetation report contains a Section 3 "Recommendations which includes <br />recommendations for revegetation sample design to be followed in future bond release <br />sampling efforts. The Division is in general agreement with the recommendations of Section <br />2 <br />