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' Kathy Welt, MCC July 20, ] 998 ' Page 5 Exhibit 3: Aline graph showing the cumulative volume of water generated by the 1 accumulation of the monthly flow rates shown in Exhibit 2. The following key points were made during Jonathan's presentation: ' • There aze two key dates to keep in mind as discussed by Kathy. First, May 1995 is when Panels 1NW through SNW were sealed and accumulation of water in these panels began. Prior to this date, all water was collected and pumped out of the mine. Second, November 1996 is when MCC began to pump lazge volumes of "dirty" fault water into the sealed sump. Prior to this date, the only water pumped into the sump was minor ' process water and inflows from west end of the mine estimated at 5 to ] 0 gpm. • As noted, Exhibit 1 depicts the area that would be occupied by storage volumes of 10 (purple shading) and 30 acre-feet (blue shading). These numbers essentially bracket the volumes of water that would accumulate in Panels 1NW through SNW based on the estimated inflow rates of 5 to 10 gpm occurring from May 1995 to November 1996 (i.e., ' S gpm for 18 months = 12 AF and ] 0 gpm for 18 months = 24 AF). • For hydraulic calculations, the best available data were used. With respect to the permeability, or hydraulic conductivity, the best data were from slug tests performed on three of MCC's B-Seam monitoring wells. The low permeability values from these test are confirmed by previously mentioned observations in the horizontal drill hole; the lack t of water in the coal face when MCC mined up to and through the faults containing water under pressure; and the relatively constant sump water surface elevation (based on observations at the Lone Pine seals). • For water accumulating at the northeast comer of 1NW, the maximum potential outflows to the Bear No. 3 Mine were calculated for volumes of ] 0 and 30 AF. At ] 0 AF (purple ' shading), there would be no water tributary to the Bear Mine. At 30 AF (blue shading), the total potential outflow would be approximately 1 gpm, with less than half being tributary to the Bear Mine. • Similaz calculations were performed for water accumulating at the northeast corner of SNW. This location is important since Beaz staff reported a wet rib down dip from this location about March 1995. Even at 30 AF (blue shading), the maximum potential outflow is less than 1 gpm and water could not accumulate in SNW at this location until after May 1995, when MCC completed the seals. The value of less than 1 gpm should be ' contrasted with the observed inflows in the Beaz Mine in June 1995 of 18 gpm. • It was also noted that these calculations based on Darcy's Law are for sump outflows and ' not Beaz Mine inflows; the travel time through the unmined coal block has not been accounted for to simplify the analyses. The compazison shown in Exhibit 2 would be more prevalent if the travel time were considered. That is to say, Beaz's observed ' inflows, as reported in their AHRs, cannot be accounted for by MCC's water management practices.