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• • 3 pond must average 8.0 feet deep to hold the 100 year event. The pond will be excavated t hold at least this amount of water, therefore, the pond is adequate and no discharge permit is needed fo site. The dam for the pond will be only 4 feet high and most of the volume will come from incising the pond into the existing terrain. Material excavated from the pond will be crushed and sold for roadbase. The 4 feet high dam will be constmcted to sideslopes of 2.SH:1.OV and will be compacted to 90% of the maximum dry density. There will be a 6" deep spillway cut into the top of the dam for a distance of 5 feet although the dam will never discharge for the 100 year event. The two collection ditches will be 1.SH:I.OV sideslopes and 1.5 feet deep; they will be cut from the existing surface. The grade of these ditches is below 5% to the sediment pond. An earth berm of 1.5 feet height will be installed on the south edge of the permit area to keep undis- turbed runoff from entering the permit area and the sediment pond. 5. Mining Timetable Mining of the 7.25 acre disturbed area will last approximately 5 years, depending on equipement, weather and gravel demand. Mining and reclamation are expected to be completed by the year 2005 or 2006. Assuming that the total reserve is 220,000 cubic yards, this is approximately 352,000 tons. At a rate of 70,000 tons per year, the deposit would be mined out in 5.0 years. The following timetable is a best estimate of the sequence of operations for the life of the mine: Task # Description Time Needed 1 Construct Ditches, Berm & Pond 0.5 mos. 2 Strip Initial Topsoil and Subsoil 1 month 3 Move in Facilities and Equipment, Set Up Operation 0.5 months 4 Mine Phase 1 reserve of 97,030 tons 38 months 5 Mine Phase 2 reserve of 100,260 tons 40 months 6 Final Reclamation 2 months Total: 82 months or 6.8 years Ferrero Pit 2/00 19