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IC ~s ~ ~ 1' S ~ ~ I^'I m-.~,oo- d~ ~ ~-. Water Information ~ General EXHIBIT G r/ ~1 ~ ~~ Mining at the Riverbend Pit will intercept shallow goundwater, which lies from three to six feet below the current ground level. Deeper bedrock aquifers that underlie the site will be unaffected by the mining operation because of the shallow depth of excavations. A Groundwater Monitoring Program is enclosed as a guideline for monitoring and mitigation measures. Upon completion of mining, eight ponds will remain unsealed for recreational purposes, one pond will remain unsealed for augmentation recharge, three ponds will be sealed for water storage, and seven ponds will be filled with silt and reclaimed to wetlands or uplands. The open water ponds will cover an area of approximately 320 acres. The sealed ponds will cover an area of approximately 105 acres. Local surface water ponds, ditches, water courses, and tributaries are shown on the pre- miningmap. The nearest water course is the South Platte River. No impact to the South Platte River is expected as a result of mining. Potential Water Resource Impacts The Riverbend Pit sand and gavel operation will have minimal impacts on the water resources in the area. There are 13 wells located within 600 feet of the proposed Riverbend Pit, however octly two can potentially be impacted. The remaining 11 are either controlled by Lafarge or located on the other side of the South Platte River. Copies of the original Riverbend Gravel Well Permit Application and Substitute Water Supply Plan are enclosed; amendments to both documents to include additional acreage are currently under draft. Discharge Permits The proposed mine will be dewatered and operated as a dry mine. Alluvial goundwater from pit dewatering will be discharged into the South Platte River, in accordance with CDPS permit conditions. T'he estimated discharge rate during dewatering will range between 800 gallons/minute (gpm) and 5500 gpm, varying according to season and production rates. The applicant has an active certification authorization to discharge under the CDPS Industrial General Permit, number COG-500416, for the original 237 acres. The CDPS permit will be renewed and amended to include the entire 1,368 acres upon its expiration on September 30, 2007. Please see enclosed CDPS permit. Surface Water Management ~t M~.. Please see the enclosed Stormwater Management Plan. ~'~~`~~ ' Consumptive Water Use ~ ~~~ 13 2005 ~ plmision of pM1in::i'~ t1 ranlo6d DMG 1 [I Perini! Poge 26 oJ86