2002-12-12_REVISION - M2001085 (7)

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southwest portion of the mining area, concurrently with mining, and also proceed in a counter clockwise direction. Mining and reclamation will generally proceed in five phases, as described by the following table. Mining Months Activity Mined Reclamation Phase Acreage in Area 1 2 Removal of overburden and topsoil; 38.3, to a initial mining to approximately 5 feet depth of above groundwater. Stockpiling of approx. 5' material from the originally permitted above the area of the 124`h Estates Sand and historic Gravel Mine. water table 2 4 Construction of slurry wall and 0 processing and transport of stockpiled material. 3 12 Construction of dewatering sump and 11.6 dewatering, following completion of the slurry wall. Mining to bedrock in Area 1 4 18 Mining in Area 2 and backfilling in 11.6 1 Area 1, as practicable, to attain 3:1 reclaimed slopes. 5 24 Mining in Area 3 and reestablishment 15.1 2 and 3 of 3:1 slopes in Areas 2 and 3, as practicable; placement of clay liner in Areas 1, 2, and 3. Phase 1 In Phase 1 of mining activity, approximately 6 inches of topsoil will be stripped from the entire mining area and stockpiled in the southern portion of the site, as shown by the Mine Plan Map in Exhibit C. Between three and six feet of overburden will also be stripped from the entire site and stockpiled, separately from topsoil, as shown by the Mine Plan Map, in the southern portion of the mining area. Approximately 30,000 and 280,000 yards of topsoil and overburden, respectively, will be stockpiled. After stripping topsoil and overburden, sand and gravel will be recovered over the entire mining area, down to a depth of approximately five feet above the water table. Nine soil borings, evenly distributed over the mining area, in July 2002, showed that the water table beneath the mining area was from 6 to 18 feet below the ground surface. Greatest depths to groundwater were generally evident along the north, east, and central portions of the site; and the shallowest depths to groundwater were along the site's west central and south central boundaries. Because of the varying depths to groundwater, initial excavation activity will be only to depths of a couple of feet to about thirteen feet below the ground surface. The result of this initial excavation will be a flat platform for Application to Amend - 6 - DMG 112 Reclamation Permit No. M-2001-085 Prepared by Scott Keen, December 2002 124`h Estates Partners 124`h Estates Sand and Gravel Mine Henderson, Colorado