2008-09-17_REVISION - M1980244 (28)

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contours of the edge of the volcanic rocks developed for the diatremal pipe, as would be • expected, as most of the gold mineralization in the district is in the volcanics. The water level in the shaft of the closed Cameron Mine was reported as being at 9,300 ft elevation, slightly above the lowest elevation of the mine (Hamm, J. C., 1972. Cripple Creek Hydrology - Cameron Mine. Internal report, Golden Cycle Corporation, dated August 8, 1972). This elevation is approximately 450 feet below the "overflow point" for water in Grassy Valley to exit the diatreme to the east lnj flowing over the lip of the Precambrian rock on the alignment of Grassy Valley, which is at approximately elevation 9,750 ft. This demonstrates that infiltrating water in the vicinity of the Cameron Mine is draining to a location that is not Grassy Valley. The water infiltrating to the diatremal rock in Grassy Valley must therefore pass through or over the subsurface granitic spur (wall) separating the Grassy Valley volcanic feeder of the diatremal lobe to the Southern lobe (Figure 2 included as Attachment 8). This is likely: the "overflow point" in the diatremal rock between the Grassy Valley feeder and the Southern feeder and is located at an elevation a little below 9,000 ft. This is some 300-400 feet lower than the water level in the Cameron Mine, which is located approximately 5,000 feet northwest of this overflow point. In addition to flow in the diatremal volcanic rock over this overflow point, it is probable that some water passes through the 2,000 foot thick Precambrian rock wall separating the Grassy Feeder from the Southern feeder. The head drop across this wall is approximately 2,000 feet, creating a hydraulic gradient of approximately unity driving • water through this feature D. The operator's consultant in explaining how the diatreme flow rate is channeled thru the Carlton Tunnel utilized the flowing assumptions. a) Moffat Tunnel. 1. "Flow from the tunnel ceased when tunnel at lower elevations reduced the water level in the diatreme below the elevation of the tunnel". This statement is not accurate. When Amendment # 6 was approved by DRMS, the MLRB instructed the Division to monitor the flow rate in the Tunnel. CC&V placed a weir inside the portal at approximately 1200 feet or less from the portal entrance, at the Iron Master stope, due to concerns raised by part owner of the portal Mr. Chuck Dagger. The Division has recorded flow rates from this weir ranging from 55 gpm to 110 gpm, which drain to underground workings inside the tunnel. Granted no flow rate is observed from the portal, but there is a recorded flow rate data for the tunnel. Please explain. Response: The statement made by CC&V is correct. Flow from the Moffat Tunnel ceased when drainage commenced at lower elevation in the diatreme. Some localized flow continued underground, as would be expected, due to movement of water downwards towards the water table in the • diatreme. The Tunnel is capable of intercepting some of this water, and it would be expected to flow locally in mine workings until it finds a fissure or other conduit to resume its vertical movement in the diatreme, ultimately arriving at the lowest installed tunnel. As such, there 25