Laserfiche WebLink
determined by Seneca Coal Company to be 11.4 inches. Topsoil depths ranged from 8 inches <br />up to 14 inches. <br />Topsoil Summary: Based on the soil replacement thickness documentation provided by SCC in the <br />SL-3 application, and additional soil replacement thickness verification performed by the Division <br />and summarized above in this section, the Division finds that an adequate topsoil thickness consistent <br />with applicable permit requirements was replaced throughout the 1793.5 acre original SL-3 release <br />request area. With respect to BRB-2 and BRB-3 (for which the Division proposes to approve Phase <br />Il bond release), the conclusion that adequate topsoil thicknesses have been replaced is supported by <br />statistically valid vegetation sample results demonstrating achievement of an effective cover of <br />desirable vegetation that meets the approved standard. <br />Vegetation Cover and "Bare Area" Assessment <br />Vegetation cover success criteria and success demonstration methods for BRB-2, BRB-3, and BRB-4 <br />are presented in Appendix 13-13 of the approved permit. Summary statistics and narrative evaluation <br />are included in the SL-3 bond release application text; transect data tables are presented in <br />Attachment E of the SL-3 application document. More extensive reclaimed area sample data, <br />documentation, statistics, and sample transect map locations are presented in the Seneca 112006 <br />Annual Revegetation Report (referenced in the SL-3 application). <br />Based on summary documentation presented in the bond release application, the applicant concluded <br />that the approved reference area cover standard was achieved within each of the three bond release <br />blocks included in the SL-3 release request area. Observations made during the inspection supported <br />the sampling results reported. There were no significant bare areas or areas where cover was <br />obviously insufficient and contributing to excessive erosion. Almost all of the erosional areas <br />observed appeared to be remnant from an earlier stage of reclamation, or a consequence of <br />concentrated flow from an obvious source, such as an existing or former road or ditch. <br />A review of the applicable cover sample data and sample maps conducted by the Division subsequent <br />to the inspection revealed errors regarding the cover sample for BRB-4. Due to the cover sample <br />discrepancies, the Division determined that a statistically valid demonstration of successful vegetation <br />cover establishment was not provided for BRB-4, and as a result SCC withdrew BRB-4 from the <br />bond release application. <br />Demonstration of vegetation cover success for BRB-2, the interim program area, requires quantitative <br />sampling, with success determination based on narrative evaluation supported by data. For BRB-3, <br />success demonstration requires statistically adequate sampling and comparison to a reference area <br />standard, with hypothesis testing if necessary to demonstrate that reclaimed block herbaceous cover is <br />not less than 90% of the reference area standard. For BRB-2 and BRB-3, statistically valid sample <br />data demonstrated that the 90% of reference standard (31.9%) was easily met, and hypothesis testing <br />was not warranted. BRB-2 allowable cover sample mean was 46.1 %, and BRB-3 allowable cover <br />13