2008-01-28_REVISION - M1997054 (35)

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-.. .- • prior mining area so that all previous mining will eventually be reclaimed after mining is completed. Initial activities at the Sandstone Quarry site will include topsoil salvage and placement into the storm water diversion berms or, if any is left over, onto the temporary top soil stockpile. Some topsoil maybe available for salvage from the nearly level plant area while little if any is available from the quarry site. Based on the original permit, approximately 67% of the disturbed area consists of rock outcrops, surface rock exposures and soil less than 6" deep to bedrock. Shallow soils to a. depth of 9" to bedrock occur over the remaining 33%. Any topsoil salvage will be fairly marginal in both quantity and quality (chemical and physical characteristics). Less than half of the top 9" could be recovered as suitable topsoil. Salvageable depths occur in a mosaic with rock outcrops, surface rock exposures, tree stands and shallow soils making most salvage operations problematic. About 700 to 800 cubic yards of top soil is currently expected to be salvaged from the sandstone quarry area. This material will not be salvaged at one time but will be salvaged incrementally as the sandstone quarrying proceeds from the southwest to the northeast. The quarry floor and plant area will be graded to be free-draining into a small stormwater berm, pond and outflow at the south end of the area. The drainage control system has been designated and will be constructed to handle storm runoff from 10 to 100 year events from the mining area and the watershed. directly above the sandstone mining area These erosion control measures will be maintained for the life of the project and be retained after mining for additional erosion control. RECLAMATION PLAN At the end of mining, the sandstone quarry's access ramps and loading areas will be removed and/or backfilled to a 1:1 or flatter slope with rock talus. The rock extraction areas along the northwest, north, and northeast areas will be left "stair-stepped" in lifts varying from a few feet to several feet high and deep following the existing bedding plane angle back toward undisturbed rock outcrop. The final slope configuration will not exceed 1:1. No vertical step of the final quarry site will exceed 8 feet. The steps will vary in height and depth to attain as natural appearance as possible. Large rock talus, +8 inches, will be placed in the drainage channel of the site to control storm run-off. Topsoil and/or the topsoil admixture will be placed on the flatter areas of the mined area on either side of the drainage channel. The planting medium will not be placed in the flow path of any storm drainage. The soils will be revegetated with seed mixtures similar to those used in the granite quarry listed in Exhibit F. Also, see the final mining and reclamation map of the sandstone area to review the final configuration and topographic projection of the area. The topographic appearance of the mined area will be quite similar to the original topography due to the mining method used following the existing bedding plane dip. The steeper zones presently seen close to the drainage channel on the Pre-Mining Plan Map, Exhibit C, will be reduced and moved towards the limits of the affected land boundaries from the proposed mining. A safer land topography will exist after mining than currently exists. There will be no highwalls involved in the final reclamation of the sandstone quarry. The reinforced concrete used in the 2 pilings of each crossing across the Tallahassee Creek will be removed, broken and buried in gravel area IB.