2011-04-06_REVISION - C1980005 (3)

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Seneca 11 Mine SL-5 Phase 11 Bond Release Request March 2011 • 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. Grazing. -Livestock grazing encourages re-establishment of native diversity and woody plant density. The grazing season at Seneca II runs from mid July to mid September. Livestock grazing was initially introduced in 1987 in the 356 acre Wadge Pasture. By 1996, the entire area was opened for grazing and approximately 254 head of long yearlings were pastured. In 2010, the grazing number had increased to 994 head of long yearlings. This 2010 grazing program resulted in approximately 24.8% utilization of the total PSCM and Seneca II reclaimed land production. Results of grazing utilization are presented in the Seneca II Annual Reclamation Reports for each year since 1988. • Topsoil Replacement • Early topsoil balance estimates (1986) indicated that a mean thickness of approximately 12 inches would be available for replacement and after 1993 typical replacement thickness ranged between 9 and 15 inches (Seneca 11 Permit - Tab 13, Postmining Land Use). Exact dates of topsoil replacement are not available, however the dates that revegetation occurred are shown on Map 2, Chtonological 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 (933) were taken over the 1793.5 acres Seneca 11 area which translates to one (1) sample per 1.9 acres (the minimum sample density is 1 sample per 5 acres). Since the topsoil sampling effort was contained within the entire original Seneca II area, there is no way to single out exactly which samples were specifically associated with the current bond • release area. Therefore the results of the entire sampling effort are used. The results of this sampling indicate an average replacement depth of 15.6 inches over the entire area including the 4