2008-08-15_PERMIT FILE - C1982056A (5)

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The surface disturbance resulting from construction of the mine water pipeline rnnning from the 6MN Million-Gallon Tank to the 10-Right Dewatering Pipeline, was reclaimed concurrently with pipeline installation. After placement of the pipeline in the excavated trench, the excavated material was backfilled into the trench and compacted around and over the pipeline, topsoil which had been windrowed to the side of the trench excavation was re-spread over the disturbed area, and disturbed azeas were reseeded with the standard rangeland seed mixture. When use of the pipeline is no longer necessary to support ongoing or future mining operations, the pipeline will be plugged and stubbed-off below grade at both ends, and abandoned in-place. Truck Loadout When the Truck Loadout is no longer needed to support coal transport operations, it will be removed and the associated disturbance azeas reclaimed. Reclamation will involve removal of all Loadout and conveyor structures and equipment; demolition of the Truck Loadout Building and associated foundations, conveyor bent foundations, and the coal reclaim and escape tunnels; removal of culverts, regrading and reestablishment of drainage; soil material replacement; and revegetation. Equipment and scrap steel resulting from building and tunnel demolition will be loaded and hauled off-site for reuse, salvage, or disposal. Concrete slabs, foundations, support piers, and caissons will be broken-up to at least one- foot below grade and the resulting concrete demolition debris will be disposed of in either the .mine portal azea or the reclaim tunnel excavation. Given that it will be well below the design reclaimed surface, the concrete feed bunker will be collapsed and buried in-place. Culverts will be removed, the reclaim tunnel will be backfilled, and stockpile and facilities areas will be regraded consistent with the design postmining topography to a stable configuration which blends with the surrounding terrain and promotes effective through drainage. Given that the Truck Loadout azea was previously disturbed, any stockpiled topsoil salvaged during the original disturbance activities will be replaced, and the azea will be reseeded with the pastureland seed mixture. Overland Belt Magnet (MR02-179) When the overland belt is no longer needed, it and its associated structures will be dismantled and removed from the property. The concrete piers will be demolished to three feet below grade and the concrete will be hauled to the pit for • burial. The metal from the framework will be recycled and the magnet offered to sister companies for use. The concrete pad will be demolished and hauled to the pit for burial. The area then will be graded and reclaimed as per the previously approved plan. Soil Stabilization Plan Proper site preparation and soil handling strategies will be utilized to control wind and water erosion. The movement and manipulation of topsoil materials in a moist condition minimizes wind and water erosion. • As explained by Bauer et al. (1976), a protective surface seal develops as silt and clay fractions bond together after reapplication of topsoil. This phenomenon is attributable to the rapid evaporation of surface moisture from redistributed soil materials. Disturbed areas will be subjected to final grading, but will remain in a rough condition to assist stability and resist slippage of topsoil after reapplication. Leaving the graded surface in a roughened configuration also improves moisture permeability between the spoiUtopsoil interface (Bauer et at. 1976). Scrapers will reapply topsoil along the contour whenever possible. The tracks made by scrapers create a "terracing" effect that helps to reduce overland surface flow and the potential loss of topsoil. Following topsoil reapplication, but before seeding, the topsoil will be graded to insure a uniform and stable thickness which will be consistent with the reclamation and revegetation requirements. Prior to seeding, which will be initiated as soon as practical after final grading, topsoiled sites will be chisel-plowed in order to alleviate compaction and promote water infiltration. Chisel-plowing has been a highly.effective means of temporary stabilization prior to vegetation establishment. Dollhopf et al. (1977) reported that chisel-plowed topsoil at the Savage, Beulah and Colstrip Surface Mines were only surpassed by the radical treatment of dozer basins in reducing overland water flow from reclaimed mine sites. The water detention capacity of chisel-plowed topsoil is reported by Dollhopf et al. (1977) as 176,4001iters per hectare, or 2,521:3 cubic feet per acre. MR07-224 2.05-106.1 10/17/07