2011-02-28_REVISION - C1994082 (6)

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Yoast Mine SL-3 Phase 11 Bond Release Request February 2091 • Rill and Gully Maintenance. Spring rill and gully surveys are conducted to identify erosional features resulting from spring snowmelt and runoff. The survey results are portrayed, on maps and submitted to the Division, which is followed up by on-the-ground maintenance to rectify the problem areas. Weed Control. Reclaimed areas and mine related disturbances, such as roadsides and facilities, are monitored for noxious weed infestations. Monitoring is conducted through formal revegetation monitoring program or as qualitative observations by SCC reclamation personnel. If noxious weed infestations occur at levels that may interfere with successful reclamation, or are detrimental to stand quality, weed control is implemented. Application of herbicides has been carried out by two primary agents, outside services or Reclamation Department personnel of the Seneca Coal Company. Interseeding of Previously Seeded Areas. Interseeding is performed when necessary to ensure adequate vegetative cover is maintained to meet the revegetation criteria set forth in the approved PAP. Monitoring at the Seneca II Mine shows that adequate perennial vegetation cover is well established by the second or third growing season, indicating that the perennial species were present prior to that point though not obvious. If reclaimed areas have a low vegetative cover, including annuals, after the first growing season, the area are evaluated for perennial species density. When it is determined that the density of perennial species (excluding noxious or problem weeds) is less than one per square foot in a seeded area, then the area is interseeded using the appropriate permanent seed mix. • • Topsoil Replacement Early topsoil balance estimates indicated that a mean thickness of approximately 12 inches would be available for replacement; therefore the approved topsoil replacement depth is 1.0 foot minimum. Exact dates of topsoil replacement are not available, however the dates that revegetation occurred are shown on Exhibit B, Chronological Revegetation, and it is logical to assume that topsoil replacement occurred either in that same year or in previous years. The redistributed topsoil came either from stockpiles or was direct handled as circumstances allowed. The topsoil was replaced using scrapers and was laid down at the approximate depth required by the topsoil balance. Numerous topsoil depth samples (172) have been taken over 818 acres which translates to one (1) sample per 4.7 acres. The results of this sampling indicate an average replacement depth of 21.4 inches over the entire area requested for Phase II bond release. Based on the results of the topsoil depth sampling, the area meets or exceeds the estimated replacement depths over the entire Phase II bond release area. Attachment D, Topsoil Depth Sampling Summary, presents a tabulation and statistics of the sampling effort. The documentation for this sampling effort is presented in the permit document in Annual Reclamation Reports submitted since 2000. 3