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i~ t David Berry - 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-Seam that range from 5.0 x 10'5 to 4.0 X 10b cm/sec and values for hydraulic gradient 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 in the Lone Pine Gulch entries? If the maximum head does 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 3rd West Mains (=500 feet west of the south quarter corner of section 17). These mains 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 this 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. 4. 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. ~Bcar prcviously assunvcd the Iloa• incrcascd from IG l0 30 gpm bccausc MCC slarlcd to rapidly fill the NW Scalcd Sump. Apparcntly the roulinc use of the NW Scalcd Sump to storc opcrllional and olhcr inflow walcr incrcascd the hard on the Bair No. 3 Minc sunicicnlly to u~usc the Ilow to incra~sc.