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Seneca Coal Company <br />Phase ll Bond Release Request <br />• Topsoil Replacement <br />May 2008 <br />Early topsoil balance estimates (1986) indicated that a mean thickness of approximately 12 <br />inches would be available for replacement and after 1993 typical replacement thickness would <br />range between 9 and 15 inches (Tab 13, Postmining Land Use). Exact dates of topsoil <br />replacement are not available, however the dates that revegetation occurred are shown on <br />Exhibit B, Chronological Revegetation, and it is logical to assume that topsoil replacement <br />occurred either in that same year or in previous years. <br />The redistributed topsoil came either from stockpiles or was direct handled as circumstances <br />allowed. The topsoil was replaced using scrapers and was laid down at the approximate <br />depth required by the topsoil balance. <br />Numerous topsoil depth samples (933) have been taken over the 1793.5 acres which <br />translates to one (1) sample per 1.9 acres. The results of this sampling indicate an average <br />replacement depth of 15.6 inches over the entire area requested for Phase II bond release. <br />Based on the results of the topsoil depth sampling, the area meets or exceeds the estimated <br />replacement depths over the entire Phase II bond release area. Attachment D, Topsoil <br />Depth Sampling Summary, presents a tabulation and statistics of the sampling effort. <br />The documentation for this sampling effort is presented in the permit document in Tab 9, <br />Attachment 9-4, and in Annual Reclamation Reports submitted since 1986. <br />• Revegetation (Cover) Success <br />Vegetation establishment call be considered acceptable if the cover of the revegetated area is at least 90 percent <br />of the cover firom the reference area ar other standard with 90 percent statistical confzdence (Rule 4.15.8). <br />In 2006, the Seneca II Mine was divided into five (5) bond release blocks (BRB -1, 2, 3, 4 and <br />5) to facilitate the gathering of vegetation data for final Phase III bond release. <br />- BRB-1: Pre-Law -mined prior to SMCRA rules and regulations and is addressed under a <br />separate bond release application. <br />5 <br />