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CashMineWaterMonitodng AddanBrown <br />3.3.9.2 Mine Area Well <br />The level and quality of groundwater in the vicinity of the mine will be monitored by sampling the Cash <br />Mine Borehole, which is used for dewatering the mine void. Water flowing into the mine is in general <br />sourced in the mineralized faults and fractures that the mine exploits, so this monitor point is appropriate <br />for monitoring the quality of water in the mineralized bedrock. During the entire time that the mine is <br />dewatered groundwater will flow into the mine, and based on groundwater modeling of the system, no <br />groundwater can leave the mine void by a groundwater pathway until the water level in the mine reaches <br />approximately Level 1 (115 feet below ground surface). The modeling results are shown in section in <br />Plate 8, and are reported in Attachment 1. <br />The quality of water that enters the mine is indicative of the quality of water that is present in the veins <br />and faults that contain the gold-bearing ore. The sample taken from the mine void represents an average <br />sample of this water, collected during the period since the mine was last dewatered. <br />The Cash Mine Borehole The well was drilled in September-October 1996 for mine dewatering, and a <br />permit application has been submitted to the State Engineer by MRV on November 3, 20064. The well is <br />lined with 6" diameter welded steel casing, cemented from top to bottom with neat cement grout. The <br />borehole terminates in the mine void at Level 7, at an approximate elevation of 7553 ft msl (552 feet <br />below collar). The bottom of the hole is open to the mine void, and there is no screen. <br />3.3.9.3 Downgradient Well <br />A downgradient well will be utilized to monitor the quality and level of water that is present in the <br />bedrock downgradient of the mine. This well will monitor any impact that the mine has on downgradient <br />groundwater, likely in country rock (as distinct from an orebody). <br />The well to be used will be designated Monitor Well MW-5, and will be constructed downgradient of <br />the Cash Mine, as shown on Plate 4. This well will be 200 feet deep. <br />The downgradient well will be constructed with 90 feet of alternating 2" PVC screen and casing in 10 <br />foot lengths, located in a 100 foot long interval filled with 10/20 screen gravel pack interval. The <br />remainder of the hole will be cased with 2" schedule 40 PVC, and the annulus sealed with bentonite <br />slurry to the collar. The proposed completion is shown in Plate 5. The completion will be conducted in <br />accordance with SOP04 - Groundwater Monitoring Well Installation (attached). <br />After completion of the well, it will be developed by pumping or bailing, in accordance with SOP05 - <br />' Monitor Well Development. The well will then be tested for permeability in accordance with SOP06 - <br />Single Well Testing. <br /> <br />' 4 Adrian Brown Consultants, Inc., 2006. Water Well Permit Application, Cash Mine Borehole. Form GWS-45 submitted to the Colorado <br />State Engineer's Office on behalf of MRV, November 3, 2006. <br />' 1601A-20061106 5