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David Berty - 2 - October 10, 1997 expected since the NW Sealed sump continued to fill'. Bear is concerned the flow between the mines may exceed 30 gpm since MCC began to pump and store huge quantities of water in the NW Sealed Sump in November 1996. 2. MCC presents a compelling argument that the maximum seepage rate from the NW Sealed Sump to the Bear No. 3 Mine would be 0.7 to 8.4 gpm. These calculations are based on measured permeability values for the B-3eam that range from 5.0 x 10'5 to 4.0 X 10~cm/sec and values for hydraulic cfradient and maximum head. Bear has no reason to dispute these calculations except they apparently are not applicable to at least one isolated area between the West Elk Mine and the Bear No. 3 Mine. Bear's only concern is whether the maximum head will increase upon final abandonment of the West Elk Mine. Are hydraulic seals to be installed ir, the Lene Pine Gulch entries? If the maximum head dces increase, the Bear No. 3 Mine could be inundated with water from the West Elk Mine. 3. The isolated area between the West Elk Mine and the Bear No. 3 Mine was discovered in 1994. It is located around cross-cut 24 - 25 in the 3'' West Mains (=500 feet west of the south quarter corner of section 17). These rtlains were developed during July 1993 and were virtually dry during development. Approximately one year later, Bear noted wet spots and small flows in this isolated area. The water emerged from the floor and lower half of the rib. Apparently the barrier pillar between the two mines is fractured in tf)is isolated area. It is the only area in the Bear No. 3 Mine where MCC's water storage practices have produced any discernable impacts. It may be instructive to determine when MCC actually began to store water in the small capacity sumps in the 1 NW - 5NW longwall panels. If the Bear No. 3 Mine is an effective barometer of MCC's water storage practices, then the bleeder entries and set-up rooms for longwall panel 5NW were developed during mid 1994. MCC presents a detailed discussion of how the water will flow from the NW Sealed Sumps to the Bear No. 3 Mine, outcrop/subcrops, etc (page 13). MCC concludes that there is insufficient cross-sectional area within the B-Seam to pass the estimated inflows of 31 to 38 gpm. The water would therefore eventually discharge though the Bear No. 3 Mine, C-Seam portals. 'Bear previously assumed the Oow increased from l6 l0 30 gpm lxcause MCC staved to rapidk rill the NW Scaled Sump. Apparcndc the rowine use of the NW Scaled Sump to siorc opcnlional and other inno+v +vatcr increased the head on tlu Bcar No. 3 Mine su0icicmk to cause the Oo++ to mcrcase.