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<br />Introduction <br />The following report presents the results of a hydrogeologic evaluation and opinions of <br />' the author (Joby Adams) regarding the Durham facility operated by Varra Companies in <br />Greeley, Colorado in association with DMG Permit # M78-056. <br />I have been involved in groundwater investigation and aquifer resource evaluation <br />' projects for over seventeen years and serve as co-owner and principal hydrogeologist <br />for CGRS, Inc., and direct all construction, compliance and environmental operations for <br />' CGRS. I hold a Bachelor of Science degree in geology and a Master of Sciehce degree <br />in hydrogeology and hold professional registrations in four states. <br />' The following are my opinions based on available data. <br />- The depth to water prior to mining was on the order of 6 to 15 feet below ground <br />surface. The saturated thickness of the aquifer likely varied between 20 and 30 <br />feet. <br />' - Though significant variations can occur, the average depth to bedrock is on the <br />order of 32 feet below ground surface. <br />- The drawdown affects created by dewatering operations varies with proximity to the <br />Cache la Poudre River. The radius of influence created by dewatering (measured <br />at 0.10 feet of drawdown) is on the order of 600 feet south of the southern mine <br />face and diminishes in areas recharged by the Cache la Poudre River and settling <br />pond. <br />- Current dewatering operations will not prohibit the use of properly constructed <br />domestic water wells adjacent to the quarry. <br />- The Cache la Poudre River is a constant head boundary and dewatering operations <br />south of the river cannot affect groundwater levels north of the river. <br />- The removal of aggregate in the southern portion of the mine has been completed. <br />The additional proposed aggregate extractions to the north and west of the <br />Carbaugh residence will not exacerbate the current water table depression created <br />by mining operations. <br />