2011-01-03_PERMIT FILE - M2011001 (9)

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EXHIBIT G Water Information General Mining on the Iverson property will intercept shallow alluvial groundwater, which typically lies 7 to 9 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 bedrock 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 groundwater features within and around the site are discussed and illustrated in the Groundwater Monitoring and Mitigation Plan and in Exhibit C. Mining will occur south of the Cache La Poudre River. The mine will be dewatered by the use of perimeter drains. All water collected as part of the dewatering will be discharged into the Cache La Poudre River via discharge points as shown on Exhibit C. Upon completion of mining, the site will be reclaimed as an unlined pond. Potential Water Resource Impacts The mining operation is projected to have minimal impacts on water resources in the area. Due to the relatively thin gravel deposit, shallow excavation, natural and hydrologic boundaries and barriers, as well as distance to adjacent properties, a rather limited extent of drawdown due to the mine dewatering operation is projected beyond the Iverson Property. As addressed in the Groundwater Monitoring and Mitigation Plan (Attachment G-1), the site hydrogeology indicates that no existing permitted private wells would be significantly affected by the mine operation mainly due to the hydraulic barrier of the Cache La Poudre River and the distance of wells from the site. Lafarge groundwater monitoring wells are located between the proposed mine cell and wells located to the south of the property. Monitoring of the Lafarge wells will recognize any potential impacts to groundwater in the vicinity of these wells prior to directly impacting the well. The monitoring wells and procedures are discussed the Groundwater Monitoring and Mitigation Plan (Attachment G-1). 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. A CDPES (discharge) permit for the mining operation will obtained prior to the mining. The discharge rate will vary seasonally. Surface Water and Stormwater Management The applicant has a stormwater management plan for the mine. In Colorado, storm water discharges are covered under the general discharge permit. The Stormwater Management Plan is included as Attachment G-2. ?b. Iverson Mine DBMS 112 Reclamation Permit Application Page GI of G3