2012-10-01_REVISION - M1977305 (14)

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Roads constructed by Cotter will be scarified and planted with the seed mixture specified by the DOE. E. Ventilation Shafts At the ventholes, all surface structures will be removed. The cement pad will be broken up and placed into the shaft. Then the shaft will be plugged with either polyurethane foam with a thickness of 10 feet, or concrete with a thickness of 3 feet, placed far enough down the hole that a minimum of several feet of mine waste and one foot of soil cover can be placed on top of this plug. This cover material will be slightly mounded so that after natural compaction there will not be a depression remaining to collect any surface water. This area will then be scarified and seeded. F. Berms and Ponds All rainwater containment structures will be left in -place in order to prevent erosion of the waste rock stockpile and ore pad. All retention ponds will be seeded, ditches will not. The culvert that will be installed to divert water under the haulage road during active mining will be removed. Offsite runoff will then continue down the natural channel. G. Utilities The portable toilets, water storage tank and air compressor will be hauled offsite. H. Waste Rock Pile Using a Caterpillar D -7, or other appropriate equipment, the waste area will be pushed up and graded into the hillside to the west of the drainage culvert (see Exhibit C - Maps, Figure F2), extending the foot of the waste pile further to the south at its natural slope angle. If the waste pile is expanded to the northwest, it will be similarly graded into that hillside. Grading will be carried out so as to create a final topography appropriate for future mining, wildlife habitat, and use as winter rangeland. Slopes will approximate a 3:1 grade and will not exceed the natural angle of repose of the waste material. (The angle of repose is the steepest angle at which this consolidated material will sit naturally without constraints — see Exhibit 6.5 - Geo- stability report.) In the event that a 3:1 slope cannot be achieved, the angle of the re- graded slopes will not be conspicuously different than the angles of slopes in the surrounding terrain. The finer waste rock material as well as any salvaged soil will then be spread over the areas where it will be most beneficial such as the less sloping areas where it will not be washed away as easily. The area will then be pocked and seeded. E -3