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• Overburden and topsoil was stockpiled azound the perimeter of the pit and has also been used in <br />backfilling and topsoiling of some slopes. <br />After the mining of the Phase 1 area above the water table is completed, mining will proceed in <br />Phase 2. This is scheduled to occur in the summer of 2007. Mining will occur by a lazge track <br />hoe that will on the existing pit level and begin reaching down to pull up gravel below the water <br />table. Expected reach is approximately 24-27 feet. The gravel will be deposited on the bank next <br />to the hoe and will be allowed to drain. A loader will then load the gravel into the portable <br />crusher/screen plant which will move with the mining operation. Mining will take place at a <br />grade of 3H:1 V neaz the final water level and will take place at 2H:1 V below that level. A bench <br />of 10 feet width will be left above water Ievel for access azound the final pit lakes. <br />As mining progresses to the southem edge of Phase 3, a slope of 3H:1 V will be left in original <br />ground azound a siphon pipe which has been placed through the mining azea to keep irrigation <br />intact downstream of the site. See Maps C-1, C-2 and C-4. The pipe is a 2' diameter Schedule 80 <br />• PVC pipe that has been buried approximately 4-5 feet below the existing pit level. A total flat <br />buffer of 15' will be left from the edge of the excavation on the north side of the siphon to the <br />edge of excavation on the south side. This buffer will later become the barrier between the two <br />lakes that aze created for reclamation. The siphon has functioned for years prior to 2006 without <br />problems. <br />After Phase 3 has been mined, the operation will move to the southern end of the reserve, where <br />Phase 4 will start. Mining will now move from south to north until the southem end of the siphon <br />barrier berm is reached and the same 3H:1 V slope will be left on the southem end, creating the <br />full barrier. At this time, the site will look like that shown on Map C-4, which is after all pit <br />mining, except the road access to the southern phases. A 36" pipe with valve will be installed in <br />the barrier berm to later regulate water levels in the lakes. Once the road is removed, the site will <br />be in final configuration, as shown on Map F. <br />r1 <br />U <br />Colona Pit November 06 D-2 <br />