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NIr. Phil Schmidt March 25, 1998 Page 3 permeability greater than the amount modeled by MCC, indeed exists. The BCC observations appear credible, and they seem to indicate a source of water which expressed several months after the development of the 3rd west section, and about 1 month after the l NW - 5 NW Panels were sealed by MCC. Various MCC documents, as discussed below, indicate that storage of water in significant quantities occurred on the uphill side of the leaking rib. For example, the inflow rate to this area of the mine was l0 gallons per minute, as documented by MCC. The inflow rate would represent a total volume of about 16 acre-feet of water storage after L2 months of inflow. Such accumulations, plus the addition of operational waters, as documented by MCC, could be reasonably linked to the outflows observed in the Bear Mine. 5) The TR80 application materials indicate that during 1996, North Fork of the Gunnison River (River) water was diverted to the NW Panels sealed sump. The materials state that approximately 30 acre-feet of water were diverted to the sump. In contrast, the Wright Water Engineers (WWE) Memorandum of February 18, 1998, item #2, states that the only water contributed to the 1 NW - 5 NW Panels after May 1995 was natural inflow of less than 10 gpm. The same item #2 also states that mine process waters drained to the I NW - 5 NW Panels prior to November 1996. Please clarify these possible discrepancies. 6) Were mining process and inflow waters from the Jumbo Panels 8 and 9 collected and recovered from the sump azeas of the 1 NW - 7 NW Panels. If so, please describe the quantities of water and the flow routing, including pumping rates and duration which occurred during the mining process. 7) The statement that 30 acre-feet of North Fork water were placed in the NW Panels during 1996, coupled with the statement in the WWE Memorandum of February 18, 1998, at item number 2, indicates that MCC had the ability to pump water from the 1 NW - 5 NW Panels after the panels were sealed in May of 1995. Is this correct? If so, please describe the pumping and water management process by which water could be removed from the panels. Does MCC currently have the capability to pump water from the 1 NW - 7 NW Panels, other than through the Lone Pine dischazge location. If not, when did this capability end. 8) The 1996 AHR indicates that about 10 acre-feet of water were stored in the NW Panels during water year 1996. In addition, the 10 gallon per minute inflow rate estimated by WWE (February 18, 1998 Memorandum) would result in a total volume of approximately 16 acre- feet over 12 months. Finally, the TR80 indicates that 30 acre-feet of River water were directed to the panels. These aze significant quantities of water and could have resulted in significant discharge to the Bear Mine. How can MCC be sure that the documented storage of water in the NW Panels sealed sump did not cause the Bear Mine 3rd west discharge? NW Panels Sum~Water Balance The actual balance of water transferred to, and discharged from, the NW Panels sump has not been adequately defined. Numerous sources of data should already exist to establish the overall water