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Initial work in each phase will be improvements to existing fencing and installation of new fencing as needed, slurry wall construction (Cooley Reservoir area only), topsoil and overburden excavation and stockpiling, and dewatering trench excavation (Cooley Reservoir side only). Slurry wall construction on the Cooley Reservoir side will consist of a standard soil-bentonite slurry wall a minimum of 2' in width to form an continuous circumferential wall around the area to be mined, prior to mining. Separate slurry walls will either be installed around Phases 2 and 3, or around Phases 2, 3, and 4 as one continuous slurry wall, if PSCo. permission is obtained to cross the power line right- of-way in two places. Generally it is expected that the slurry wall will utilize a combination of on-site overburden material and imported soil-bentonite material. Dewatering trench excavation will be performed with an excavator into the underlying claystone bedrock. Trench sidewalls in bedrock will be excavated vertically to several into the bedrock, and trenches will be constructed to develop flow discharge locations and minimize evaporative losses. Ground water will drain from the alluvial sand and gravel, collect in trenches, and be discharged to the S. Platte River directly or via to be constructed temporary ditches. Discharge locations will be identified, and a NPDES permit will be processed and obtained. Storm water from any temporary roads and other disturbed areas will be managed by grading to direct storm water from disturbed areas into the excavated areas and be contained on site. A Storm Water Management Plan (SWMP) is being prepared and a SMWP Permit for Storm Water Discharges for a Sand and Gravel Operation will be obtained from CDPHE, and a copy of the application for this permit and the SWMP Permit will be submitted to the DMG prior to initiating any excavation operations. Item #5 Wash water from the Plant Site will be discharged into the excavated area in Phase 1B. Much of this area will be reclaimed as wetlands, as silt and sediment carried by the wash water will gradually fill up the excavated area of Phase 1B. Equipment that will be used on site include loaders, scrapers, backhoes, dozers, excavators, water trucks, end dump and belly dump trucks, and other miscellaneous vehicles. Field conveyors, hoppers, and transfer points will be utilized to provide conveyance to the Plant Site area. On the Fulton Wildlife Area side, trucks may also be utilized to convey material to the Plant Site. Direct export of borrow material may also be undertaken from the designated access points. Export of all processed material will occur from the Plant Site from a new entrance to be constructed onto Brighton Road. Improvements at this new entrance and on other adjacent roads will be in accordance with approvals from CDOT and the Adams County Department of Public Work. The Plant Site's entrance from 100' Avenue will be utilized for traffic for employee, visitors, etc. The narrative portion of the Traffic Impact Report prepared by Leigh, Scott, & Clearly, which discussed traffic generation from the facility and proposed improvements, is included at the end of this submittal. Mining phases are described on the next several pages. Mining will create 0'H to 1'V excavation slopes. Item #7-:Sorenson's comments Final slopes will be reclaimed to 3H:1 V slopes from ground level to the depth of the excavation. Except for Phase 1B, reclamation will be concurrent with mining, as backfilling of overburden and topsoil, grading, and planting will follow the mining operation in each phase. Exhibit E, Reclamation Plaq and Exhibit F, Reclamation Plan Map, provide details of site reclamation, which in general consists of backfilling, regrading, planting (above water line), and armoring the upper reservoir slopes for wave resistance. 2