2009-10-16_REVISION - M1977036 (8)

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Monitoring Well Installation Lafarge has installed a total of 6 monitoring wells in the area of the Greeley 35 h Avenue Mine. Three of these wells are on the Lafarge Brown property and three are near the permitted mine. The monitoring wells were installed outside the limits of contemplated mining, but near the proposed permit boundary, so that groundwater levels can be monitored during and after mining. The monitoring wells were constructed of 2-inch Schedule 40 PVC casing and screen extending to the bedrock. Each of the monitoring wells was finished at the surface with a locking, above ground, steel protective casing set in concrete. The objectives of the well installation and monitoring program are to monitor current groundwater conditions and to provide a basis for assessing potential effects to groundwater levels during and after the proposed mining. Through the well monitoring program, pre-mining groundwater elevations, flow patterns across the property, and seasonal fluctuations will be documented. Well Inventory A well inventory for the site and adjacent areas was conducted to identify wells near the project. The inventory consisted of a review of well records (Registered Wells) on file with the Colorado Department of Natural Resources, Office of the State Engineer (SEO) as well as mailings and meetings with nearby property owners. The State records search indicated that there are fifteen permitted wells (excluding those in the permitted mine) listed within 0.5 miles of the Lafarge Brown property (Figure 1). Fourteen of these wells are on the opposite side of the Cache la Poudre River. SEO requires a 600-foot well spacing agreement statement from the well owners who have wells within 600 feet, at least six months prior to the commencement of mining of a relevant phase. The well research indicated one permitted well within 600 feet of the proposed permit boundary. This well, identified below, is within 600 feet from the closest proposed mine excavation and is on the opposite side of the Cache la Poudre River. Permit: 30523 Owner: Gino Tori 4704 West O Street Greeley, CO 80631 Use: Irrigation Location: NE'/4 NE'/4 Sec. 34,6N, 66W The owner reports this well is 42 feet deep, 6-inches in diameter and is used to irrigate 1.5 acres at a pumping rate of 12 gallons per minute. Mining on the Lafarge Brown property is not expected to have significant effects on this well because primary mining/dewatering activities near the well will be on the opposite side of the Cache La Poudre River. Greeley 35' Avenue Mine (M-1977-036) DRMS 112 Reclamation Permit Amendment Application Groundwater Monitoring and Mitigation Plan Page 2