2011-11-14_REVISION - M1986015 (8)

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4. Public Use • After reclamation, the operator is not permitting public use. • • 5. Reclamation Measures — Materials Handling The grading of the excavation is for backfilling of the hole with excess sand, clay, and overburden. The final topography will be approximately eleven feet below the existing grade and at least two feet above the average groundwater level. Approximately 20 acres per year will be excavated to satisfy the demand for sand and gravel. The topsoil and overburden from the first year's excavation will be stored along the northern setback areas. As the mining of the sand and gravel commences, this material is first run through a screen plant at the mine face to separate out fine sand and clay. The recovered sand and gravel is transferred to the field conveyor, while the reject sand and clay is moved to the rear of the excavation area and placed as backfill. There will be enough reject material to backfill the first ten to 13 feet of the hole. In the second year of operation, the stripped overburden and topsoil from the second 20 acres will be placed on the reject material of the first year mining. The backfill material will be compacted by the continuous movement of the scrapers and dozer over the site. In the third and last year of mining, the stripped overburden and topsoil from the last 14 acres will be placed on the reject material of the second year. The reject material from the third year mining will be place as backfill in this pit area. When the third year mining is done and the hole partially backfilled, the overburden and topsoil from the first year mining, stored along the northern setback area, will be moved on top to the reject material. Each year, we anticipate that the overburden and topsoil will be inadequate to fully fill the pit to its proposed grade. Each year the operator will leave a depression(s) in the backfill area, which total two acres in size and are 13 feet deep. Washer fine slurry will be pumped from the Phase 1 area to fill these depressions. Thus the earthwork is completed and the backfill results in a depressed basin at eleven feet fellow existing grade. The material in the levee along the south and west sides of the excavation will be dozed over the depressed basin and incorporated into the backfill when mining is completed. The setback areas will be benched by a dozer and that material will be pushed over the depressed basin and incorporated into the backfill. See the cross sections on Exhibit F. In the reclaimed state, this porous sand reject material in the bottom half of the backfill will facilitate the flow of groundwater through the backfilled pit. The backfilling process occurs during both the current year and the following year of the mining. No acid forming or toxic producing materials will be handled or placed in the reclamation. No release of pollutants to the surface drainage system will occur. The backfill area is approximately eleven feet lower than existing grade surrounding the mine. The slopes down into the depressed basin will be at 3:1 grade. The bottom of the depressed basin will be sloped gently (0.5% to 1.0% grade) toward the three runoff channels in the River bank. Thus the depressed basin will not retain runoff.