2014-11-25_REVISION - M1979191 (21)

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The slope liner is designed with 20 -foot wide crest sloping 1% toward the reservoir. The crest transitions into a 3:1 (H: V) slope extending to bedrock. Stability and seepage analyses indicate this slope configuration and crest width will be stable under existing site conditions. Overburden obtained from the stripping on Di441ie- Veldman property soil appears to meet project specifications for slope liner embankment fill. This overburden will be utilized as a borrow source during slope liner construction. A cutoff key is designed at the base of the liner, offset approximately 5 feet from the prepared mine highwall. The cutoff will extend five feet into the claystone bedrock as directed by-6E4-during construction. The key will be approximately 118 feet wide at the base. Approximately 1 foot of weathered bedrock should be stripped from within the slope liner footprint. Material excavated during foundation preparation including contaminated pit run and bedrock should be placed within the footprints of the ponds @F plaeed .. idiia the Phase ^ 5 baekfill areas. This material should not be utilized as roadway fill. Shaping of the reservoir bottom should not encroach within 25 feet of the toe of the slope liner and reservoir floor excavation slopes, if necessary, should not exceed a slope of 6:1. The reservoirs should be graded to the bedrock low point, as noted in the construction plans. 5.2 Top Soiling Topsoil placement will occur as reclamation activities as areas are free from mining activity. Primary areas to receive topsoil as reclamation during the mining process are low -lying areas and other areas in need of fill, such as haul roads and haul roads which lie above the normal high water level (NHWL). Site access roads will be remain in their current state through reclamation. 5.3 Wildlife The wildlife plan will not change from the original permit issued, Permit M- 1979 -191. 5.4 Revegetation Revegetation will occur concurrently with the mining process as is practical. Care will be taken to regrade and provide reclaimed slopes such that revegetation regrowth may occur to help comply with state and erosion standards. Seeding and grassing activities will take place immediately upon completion of reclaimed slopes (season permitting) whenever practical size areas become available and free from mining activity. Areas not planned for revegetation include Phases 1, 3, and 4 as they will become below -grade ponds. Based on SCS guidance for other local projects having similar surficial soils, the following revegetation procedures are anticipated: