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West Elk Mine • inflows similar to previous years (12 gpm) from other sections of the mine. In July 1997, the fault inflow in B East Mains dried-up as inflows began in the down-dip expression of the same fault system in the 14SE Tailgate. Inflows were initially about 200 gpm, but quickly diminished to less than 100 gpm. In January 1997, a second water-bearing fault system was encountered in the 14SE Headgate. Initial inflows from the 14HG Fault were estimated in excess of 8,000 gpm (January 20, 1997) dropping to 2,700 gpm by Januazy 27, 1997 and to 1,750 gpm by January 31, 1997. By April 1997, inflows from the 14HG Fault had decreased to approximately 200 gpm. Similaz to the BEM Fault, in September 1998, when the 14HG Fault system was mined through in the 14SE Tailgate, the headgate inflow dried-up and the inflow began in the tailgate entries along the down-dip expression of the fault. Total 1997 inflows from the BEM Fault were approximately 161 acre feet and from the 14HG Fault were approximately 504 acre feet. In 2002, the total inflows from these two fault systems were estimated to be 129 acre feet. • Groundwater inflows, other than those associated with the fault systems described above, aze primarily observed neaz portal areas under low cover (less than 300 feet) near drainages and are generally responsive to spring runoff • Available data demonstrate that there has not been a measurable impact on springs or surface water strictly attributable to F and/or B Seam mining • • Groundwater levels have been observed to decrease directly as a result of F Seam retreat mining, but recovered to pre-mining levels following panel subsidence In 1998, CDMG approved the Box Canyon permit revision (PR08) for West Elk Mine. Much of the information contained in the Box Canyon Decision Document (CDMG 1998) regarding the current permit area is directly applicable to the probable hydrologic consequences anticipated as a result of mining the South of Divide permit revision area. Regional MininP Experience Considerable mining of the coal-bearing units within the Mesaverde Formation has occurred, not only at West Elk Mine, but along the North Fork Valley. As a result, there is substantial information known about the hydrologic consequences of mining the coal-bearing units within this formation. The CHIA (2001) provides a valuable summary regading the general hydrologic conditions and consequences of mining in the North Fork Valley. The following statements (including page references) aze included in this document. Unless otherwise noted, and based upon WWE's analyses, these statements apply directly to the permit azea: 1. "Four categories of potential aquifers occur in the Somerset coal field. These aze; (a) The alluvium and terrace deposits associated with the North Fork of the Gunnison River; (b) The • localized, shallow alluvium along creeks tributary to the North Fork; (c) The discontinuous 7.05-I51 Revised November 1004 PRIO