2009-10-16_PERMIT FILE - M2009082 (9)

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EXHIBIT G Water Information General Mining at the Parsons property will intercept shallow groundwater, which typically lies 5 to 15 feet below ground surface. Deeper bedrock aquifers that may underlie the site will be unaffected by the mining operation due to the shallow depth of excavations and low permeability strata beneath the shallow sand and gravel. A Groundwater Monitoring and Mitigation Plan is provided (Attachment G-1) as a guideline for monitoring and mitigation measures. Pertinent water features within and around the site are discussed and illustrated in the Groundwater Monitoring and Mitigation Plan and in Exhibit C. Mining will occur both north and south of the Cache la Poudre River. The various mine phase areas will be dewatered by the use of perimeter drains. All water collected as part of the dewatering will be discharged into drainage ditches then into the river. Upon completion of mining, there will be eight unlined ponds (approximately 60.0 acres) incorporated as part of the reclamation plan for recreation and wildlife habitat. Potential Water Resource Impacts The Parsons mining operation is projected to have minimal impacts on water resources in the area. Potential water resource impacts, in terms of drawdowns on groundwater levels, are addressed in the Groundwater Monitoring and Mitigation Plan (Attachment G-1) and Groundwater Modeling Evaluation (Attachment G-2). Due to the relatively thin gravel deposit, shallow excavation, phased operation, and natural and man-made hydrologic boundaries and barriers, a rather limited extent of drawdown due to the mine dewatering operation is projected. As addressed in Attachments G-1 and G-2, the site hydrogeology and groundwater modeling indicate that no existing permitted private wells would be significantly affected by the mine operation. Discharge Permits The proposed mine will be dewatered and operated as a dry mine. Alluvial groundwater from the dewatering will be discharged to the Cache la Poudre River, in accordance with CDPS permit conditions. The discharge rate will vary seasonally. The applicant will apply for a CDPS Industrial General Permit (for Sand and Gravel Mining and Processing General Permit). Surface Water and Stormwater Management The applicant will prepare a stormwater management plan and obtain a permit for Stormwater discharges from the CDPHE prior to mining activities. The Stormwater Management Plan is :included as Attachment G-3. Site Drainage Hydrologic analyses of existing, mining, and reclamation conditions of the project are summarized in the Preliminary Drainage Report (Attachment G-4). Parsons Mine DRMS 112 Reclamation Permit Application Page GI of G3