2008-07-10_PERMIT FILE - M2008006 (4)

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SERFER PIT GROUNDWATER MONITORING PLAN This report presents the SerFer Pit groundwater monitoring plan proposed by Connell Resources, Inc. The site is a proposed sand and gravel operation located near the Town of Windsor, Colorado. The proposed mining operation is located in the Northeast corner of Section 24, Township 6 North, Range 68 West, Sixth P.M. in Larimer County. The site is bordered on the east by County Road 13 and on the north by State Highway 392. To the south the limits of mining are bounded by the Cache la Poudre River and the property line on the west. The location of the site is illustrated in Figure 2. The permit boundary will encompass approximately 45 acres with approximately 30 acres designated for mining. The remaining area will consist of setbacks from roads and the Cache la Poudre River, utility right-of-ways, and site access roads. The SerFer property is located in the lower Cache la Poudre River basin. The proposed mining operation will have minor impacts on the Cache la Poudre River from depletions due to evaporation of dewatered groundwater and operational losses. Based on the results of this analysis, it is expected that significant impacts to water quality and quantity can be mitigated without injury to the senior water rights. The project lies in the valley fill deposit for the Cache la Poudre River. This is an unconfined alluvial aquifer and consists of the sand and gravel that is being mined. The limits of the aquifer correspond roughly to the limits of the floodplain. The depth of the aquifer ranges from approximately 5 feet to 10 feet depending on the formation of the underlying bedrock. It is estimated that bedrock lies between 12 feet and 20 feet below the proposed mining site. The underlying bedrock is a siltstone formation that extends to greater depth. The mining of the SerFer property will be completed in 5 years. Following the completion of mining activities the site will be reclaimed, resulting in the creation of a lined gravel-pit reservoir. Prior to mining, a dewatering trench will be excavated around portions of the perimeter of the site to facilitate dry mining of the sand and gravel deposit. Groundwater will only be exposed in the dewatering trench and the collection area. Groundwater will flow along the trench by gravity toward a collection basin where it will be allowed to settle out prior to pumping into the Cache la Poudre River. During reclamation, a clay liner will be constructed around the perimeter of the mining area. The liner will act to significantly impede the hydraulic interchange between water stored in the constructed reservoir and the surrounding aquifer. MONITORING PLAN The operation is a dry mining process where sand and gravel will be excavated and hauled to an off- site processing plant. To ensure the protection of surrounding water users, piezometers will be installed on the property to monitor baseline groundwater levels prior to the commencement of the dewatering and mining operations. The purpose of this report is to summarize the existing information used to define the general baseline groundwater conditions at the site, and present a monitoring plan for use in evaluating potential off-site impacts to the groundwater system. Connell Resources, Inc. I Serfer Pit Groundwater Monitoring Plan