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Processing <br /> Unless classification is performed at the extraction site by portable crushers, the plant will be used for <br /> gravel sorting. All washing (where required) will also be performed at the plant. The plant location is <br /> shown on Exhibit D. <br /> Aggregate wash operations will use a zero-discharge system to remove unwanted fines. The water used in <br /> the system is purchased from the City of Cripple Creek, through an existing, on-site, metered tap. After it <br /> has been used, the sediment-laden process water is circulated from the wash plant through three <br /> sequential sedimentation(settling)ponds before it is pumped back to the plant for re-use. <br /> Sediment Ponds <br /> The three process settling ponds associated with the wash plant are used to remove sediment from the <br /> process water before it is returned to the plant for re-use. There is no discharge from the ponds into the <br /> surrounding environment. <br /> The ponds are located in the northeast quadrant of the site, 30 feet east of the western mine permit <br /> (property line) boundary. The pond locations provide a buffer to prevent sediment and water from leaving <br /> the site in the event of a release. In addition, a low berm will be located along the western, and west <br /> corner of the northwest property lines to control potential runoff from the site and to provide secondary <br /> containment in the event of a release. The western boundary of the mine will be fenced. <br /> Process water will move by gravity to flow sequentially from the wash plant into Pond 1 for primary <br /> settlement. When Pond 1 has reached its freeboard,it will flow over a low concrete spillway to Pond 2 for <br /> secondary settlement. The process water will then flow from Pond 2,through a concrete trough to Pond 3, <br /> where it will be pumped from a central location in the pond, via an underground return pipe where it will <br /> be reused in the wash plant. <br /> The pond berms are of earthen construction and will be reinforced with aggregate. They will be wide <br /> enough to allow a Volvo EC300 excavator(or equivalent)to track on them for periodic sediment cleanout <br /> and maintenance. Pond 2 will have a 20 foot(north-south) by 30 foot(east-west) earthen pad to facilitate <br /> sediment clean out with the excavator. <br /> Process pond design dimensions will be as follows: <br /> Pond No. East-West (feet) North-South (feet) Max Volume(cf) <br /> Pond 1 60 40 9,600 <br /> Pond 2 60 100 24,000 <br /> Pond 3 70 70 19,600 <br /> Each process pond will have a maximum water depth of approximately four feet and a minimum <br /> downstream freeboard of three feet. <br /> Page 2 of 3 <br />