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• RePla~• es~l EXHIBTT G <br />WATER INFORMATION <br />The proposed operation will have impacts on groundwater in the immediate area of the <br />affected land. Mining and reclamation plans have been designed to minimize and <br />mitigate these impacts. A substitute water supply plan will be prepared and submitted to <br />the Colorado State Engineer's Office for review prior to exposure of groundwater on the <br />site. <br />Section 1-Surface Water <br />Although the site is located near the Cache La Poudre River, no part of the site is located <br />within any regulated floodplain or floodway. ITstorically, no conveyances other than . <br />local imgation ditch laterals have crossed the site. The proposed mining activity is <br />expected to have little or no impact on surface water systems in the vicinity of the site. <br />Specifically, the Taylor and Gill Ditch Company water supply ditch is located in the <br />vicinity ofthe affected lands. Per discussion with William Seaworth, president of the <br />Taylor and Gill Ditch Company, the mining is not expected to affect the quantity of water <br />flowing in the ditch (see Colorado Division of Minerals and Geology, Minerals Program <br />Inspection Report, Pre-Operation Inspection, dated 25 June 2001. for M-2001-051). <br />However, as the majority share-holder in the Taylor and Gill, Lafarge/Western Mobile is <br />capable of augmenting the ditch water, should the need arise. <br />Section 2 -Ground Water <br />Soil bores in the vicinity of the site indicate groundwater levels at an average of <br />approximately 5 feet. The site lies within an unconfined riparian aquifer associated with <br />the Cache La Poudre River. This aquifer extends to the bedrock at 20-25 feet below <br />ground surface. In order to mine the site dry, dewatering will be required. Groundwater <br />modeling done by Tuttle Applegate, Inc., indicates that dewatering is likely to lower the <br />water table in the immediate vicinity of the site by as much as five to six feet west of the <br />site and two to four feet on the east side. The extent of these impacts range from <br />approximately 1800-2400 feet fora 1' drawdown. <br />In accordance with DMG Construction Materials Rule 3 (Section 3.1.7), a groundwater <br />monitoring program has been designed and will be implemented by the applicant to <br />determine baseline conditions and observe changes in groundwater levels and water <br />quality, particularly temperature and pH. If levels in monitoring wells show a significant <br />change, mitigation efforts will be initiated on a case-by-case basis as described in the <br />monitoring protocol. <br />The reclamation plan for the site is to create unlined water ponds. It is believed that <br />groundwater conditions will effectively return to pre-mining conditions once reclamation <br />is complete. A substitute water supply plan will be filed with the State Engineer's Office <br />for mining operations as well as post-mining augmentation requirements. This plan will <br />be approved prior to exposure of groundwater. <br />