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MINING PLAN <br />The gravel zone is approximately 30 feet thick in a alluvial deposit and is overlain by soil and <br />overburden of 1-6 feet. The azea will be mined by first excavating soil/overburden with front end <br />loaders or dozers and stockpiling the material in sepazate piles. The raw gravel material will then <br />be loaded with a loader into a portable crusher/screen plant where various sizes of product will <br />be made and placed in sepazate stockpiles. Dozers may also be used to move topsoiUoverburden <br />or gravel. Current mining limits can be seen in Map C-1. The buffer between Amendment #1 <br />and Amendment #2 has been removed. This will be replaced with compacted fill as part of the <br />reclamation. The replacement of the buffer is described in the Reclamation Plan. Future mining <br />will take place in Amendment # 2 and then move into the new Amendment #3 area. The mining <br />of the deposit will occur to the limits shown on Map C-2 and will be mined at a O.SH:1 V slope. <br />This slope will then be backfilled as per the Reclamation Plan. <br />Due to excavation below the local water table the pit must be dewatered. Currently, the pit is <br />being dewatered through the use of trenches and pumps. The trench bottoms are approximately <br />2' below the pit bottom. These trenches drain the water to two pumps. The pump along the west <br />edge of Amendment #1 pumps a majority of the pit's water into the original pit. This pit acts as <br />the sediment pond with the final dischazge being the northwest corner of the pond. A second <br />pump is used to supply water to the residences to the east. The dewatering of the pond has drawn <br />the water table down in the immediately adjacent land. This lowering of the water table has <br />effected the imgation wells used by the residences within 500' ofthe pit. This effect has been <br />mitigated through the use of a pump within the pit supplying water to the residences for the <br />watering of lawns and landscaping. Once the pit is allowed to fill with water the shallow wells <br />of the residences will again be used to supply their own water. <br />Storm water from the site will be contained within the pit. All disturbed areas within the permit <br />azea will be isolated from the surrounding terrain. This is accomplished by isolation berms, lazge <br />stockpile berms and isolation ditches. <br />It is extremely unlikely that any toxic or acid-producing materials will be encountered during the <br />mining operation since the past mining shows that the material is alluvial in nature. However, in <br />the event that such materials are encountered, they will be covered with subsoil and topsoil from <br />the stockpiles to the same depths outlined in the reclamation plan and no more mining will occur <br />in this area. The operator commits to cleazly marking the permit boundary with stakes surveyed <br />on site. No blasting will occur on this site. If any "reportable quantity" of hazardous material or <br />waste is released into the environment, the operator will notify staff of the Colorado Division of <br />Minerals and Geology as well as all other appropriate local, state and federal agencies. <br />Stability Design <br />All slopes will be kept to a maximum slope of 3H:1 V along the permit boundary. The crest of <br />this slope will be kept 20 feet from the permit boundary. United Companies mines using a <br />O.SH:1 V slope. Highwall mining will progress to a 45 foot offset of the crest line. Both <br />Pit No. 1 1 /04 1 <br />