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July 18, 2011 <br />Phase II Bond Release Criteria and Observations: <br />C- 1994- 082/Yoast Mine SLB <br />saturated; the seep was also flowing into Pond 013. <br />No recent movement was apparent in the Neck Pit area slide, but the toe areas of the slide were saturated <br />and flowing. <br />The Pond 012 slide area remains active; particularly the north slope above Pond 012 where weathered <br />shale material continues to slough off. The pipe and underdrain on the north inlet to Pond 012 were under <br />construction. A truck was hauling rock into the drain. <br />There were two pair of mallards and their young on Pond 010. Several Dusky grouse were flushed on the <br />south area reclamation. An antelope was roaming the area between ponds 012A and 014, elk were <br />utilizing the neck pit area, and a young deer was sighted at the top of the Pond 012 drainage. <br />Roads were in good condition. The outlets of culverts YA -7 and YA -8 needed to be cleared, and the road <br />ditch between YA -8 and YA -7 was in need of maintenance. Downcutting had breached the check dams <br />and resulted in a gully 3' deep and 2' wide. <br />Rule 3.03.1(b) allows for release of up to 85% of the performance bond upon the establishment of <br />vegetation which supports the approved postmining land use and which meets the appropriate standard for <br />cover. The discussion of the applicable inspection and evaluation for Phase II bond release in the <br />Division's 1995 Bond Release Guideline directs the Division to evaluate topsoil replacement thickness, <br />vegetative cover and bare areas, species composition, erosional features, the condition of sediment ponds <br />and any needed maintenance, and the construction and performance of permanent impoundments. The <br />Division's observations of those criteria follow. <br />Topsoil replacement: The required topsoil replacement depth at the Yoast Mine is 12 inches. SCC <br />sampled topsoil replacement depth in 172 locations over the entire 818 acre Phase II release request area, <br />for an average of 1 sample every 4.7 acres. The average topsoil replacement depth reported by SCC was <br />21.4 inches, with a standard deviation of 5.4 inches. The minimum depth reported was eleven inches at <br />one location. Topsoil replacement depth was not sampled during the inspection. <br />Bare Areas: One large bare area (approximately 0.5 acres) was observed in the North Pit area, on the <br />north side near the neck pit at the former TSS D topsoil stockpile location. The area is bare as a result of <br />having been treated for cheatgrass in 2009 and 2010. The area was reseeded in the fall of 2010, but the <br />seeding effort has not been successful to date. There are smaller bare areas in the South Pit area, <br />particularly along postmining channel YPM -5 -1. <br />Cover: For the most part, cover is adequate throughout all of the reclaimed areas to control erosion. <br />Exceptions occur in the immediate vicinity of postmining drainage channels YPM -13 and YPM -9 (not <br />proposed for Phase II bond release), and portions of areas surrounding YPM -5 -1 and YPM -6 -2. Rills and <br />gullies were observed in these drainages, where vegetation was sparse and dominated by weedy annuals <br />and noxious weeds (photo). <br />Composition/Diversity: <br />Overall, a diverse community of vegetation exists on all of the Phase II areas inspected. <br />Species observed include Lamb's quarters (Chenopodium album), White yarrow (Achillea lanulosa), Blue <br />flax (Adenolinum lewisii), onion (Allium sp), Aster (Aster sp.), Arrowleaf balsamroot (Balsamorhiza <br />Number of Partial Inspection this Fiscal Year: 0 <br />Number of Complete Inspections this Fiscal Year: 1 <br />Page 3 of 19 <br />