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The deposit is and will continue to be dry mined through the use of dewatering trenches <br />and pumps. Prior to mining, a dewatering trench is constructed around the perimeter of <br />each phase to collect groundwater that drains from the deposit and surrounding alluvium. <br />Dewatering trenches allow sediment to settle before the water is discharged to the Cache <br />La Poudre River, or if necessary to meet discharge quality requirements stipulated in the <br />site's Colorado Discharge Permitting System (CDPS) permit (Permit Number COG- <br />500000, Facility COG-500345), flows from dewatering trenches are circulated through <br />sedimentation ponds prior to discharge to the river. The discharge permit for this site <br />includes monitoring parameters for dewatering the sand and gravel mine and monitoring is <br />and will continue to be conducted in accordance with those parameters. Water may also <br />be pumped into other mine cells. <br />When the alluvium is sufficiently dry, front-end loaders will excavate the material and <br />deposit it on conveyors. The mining face will be nearly vertical to 0.5:1 slope. No <br />explosives are planned to be used. <br />Conveyors will transport the material to be processed at the plant site which is located in <br />the existing mining area, south of WCR 64 ("O" Street). <br />The plant site contains the crushing, screening, and washing equipment used for the <br />processing of the raw materials. The processed materials are transported to other sites or <br />used in the onsite concrete and asphalt plants or delivered offsite for commercial and <br />government projects. Other aggregate materials may be imported to the site from time to <br />time to meet certain ready-mix concrete or asphalt design specifications. <br />Commercial truck traffic will continue to access the site from the existing operation at Weld <br />County Road 27 (83RD Avenue). An access drive off of WCR 64 (O Street) will provide <br />equipment access and short term temporary haul access from the northern amendment <br />properties. Internal haul roads will be restored to their original condition or reclaimed to <br />grass land. <br />All surface water within the mine areas will drain internally. There will not be any <br />uncontrolled releases of surface water and sediment from mining areas. Storm water <br />collected in the open mine will be managed in accordance with the Colorado/NPDES <br />discharge permit for this operation. Sediment generated from localized storm water runoff <br />and surface drainage will be managed according to the Stormwater Management Plan,that <br />is maintained for the site. <br />Mine Schedule <br />The Riverview Resource operation processes approximately 500,000 to 600,000 tons of <br />aggregate per year. At this rate, Al anticipates mining and reclaiming the site in <br />approximately 12 to 15 years; however, the rate of mining and overall life of the mine is <br />dependent upon demand and market conditions. <br />Riverview Resource <br />Amendment to Permit M1999098 112c <br />Page D3 of D6