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Response: The 7-North Angle Well extends to the bottom of the F-Seam (upper coal seam), with a bottom elevation of approximately 5,586' amsl. The No. 5 Mine Sump also extends to the bottom of the F-Seam (lower coal seam), with a bottom elevation of approximately 5,600' amsl. Both dewatering sites • dewater existing F-Seam workings, including any to the south and west that are hydrologically connected. Boreholes drilled during mining between the E- and the F-Seams, as well as subsidence-related fracturing between the seams in mined areas, result in a hydrologic connection between the two coal seams. Given this consideration, any accumulation of groundwater in the E-Seam which reaches the level of the F-Seam (approximately 100' higher), will also result in contributions to the dewatering discharge. The two existing dewatering sites are currently operated in a maintenance mode to maintain water levels in the mine workings at an elevation of approximately 5,800' amsl. At this maximum level, the northern mine workings (both E- and F-Seams) on the east side of Highway 13 are flooded and very limited workings on the west side of Highway 13 are flooded, as indicated on the enclosed annotated E-Seam Workings Map. Given that active mining operations were discontinued in 1995, and that flooding of the identified areas occurred gradually, the identified areas have probably been flooded for 4-6 years. Most areas where liability release is requested are probably not in direct hydrologic connection with the lower mine workings, therefore, dewatering of these areas is not currently occurring, except indirectly, as any groundwater inflows from these areas move dawn-dip into the lower portions of the mine. It is important to note that the No. 5 Mine portals are at an elevation of approximately 6,180' amsl, or approximately 580' above the base elevation for the dewatering sites and approximately 380' above the current maximum mine water level of 5,800'. The coal seams rise sharply to the south and west of these portals, are discontinuous due to a horst and graben fault structure, and then break over the crest of the anticline near the center of Section 36. Given the structural considerations, any water accumulations in the mine workings within the fault zone and over the crest of the anticline may be partially confined, possibly resulting in some localized flooding of the associated workings. If pumping were to be discontinued, impacts on the proposed liability release areas would probably be minimal since gradual mine flooding and rising groundwater levels would reach the level of the Middle Sandstone Member and the major fault zones before impacting the upper F-Seam mine workings (above the No. 5 Mine portals). The Middle Sandstone and fault zones would act as conduits to equalize water levels and would probably transmit some of the rising groundwater to the regional surface and groundwater systems. Mapping of the final flooded mine water level is impractical due to the number of variables involved, please refer to the discussion of Probable Hydrologic Consequences in the PAP for additional information on mine flooding and related impacts. 13. Based on Map 23 ("Eagle No. S F Seam Workings") and the SG02 liability release request Map, there appears to be hydraulic communication between the F seam workings in the area requested for release and the F seam workings in the areas not requested for release. Are there hydraulic seals in the F seam workings between these areas? If sq please locate these seals on a map. lesponse: It is important to note and understand that there is a limited hydraulic connection between the F-Seam workings in the proposed liability release area and areas to the north and east due to structural considerations, as noted in the previous response. In addition, the No. 5 Mine workings were sealed, consistent with MSHA-approved mine closure and sealing plans, to control both drainage and ventilation. Given this consideration, the mined-out room and pillar sections within the liability release area were .sealed on completion of mining, leaving only the main entries open for access. Liability Release Response - No. 3 6 12/07/05