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West Elk Mine i~ 1982 and 1995 had been about 12 gpm, with a peak inflow rate estimated at 50 gpm in the B-Seam and 10 gpm in the F-Seam. In 1996 this inflow rate increased as a result of mining through the B East Mains fault. The 1996 average groundwater inflow rate to the mine was approximately 200 gpm: This is based on observed and measured inflows from the fault system (approximately 235 gpm or 301 acre-feet over 291 days) and estimated inflows similaz to previous years (12 gpm) from other sections of the mine. In July 1997, the fault inflow in B East Mains dried 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 were estimated in excess of 8,000 gpm (January 20, 1997) dropping to 2,700 gpm by January 27, 1997 and to ,1,750 gpm by January 31, 1997. By April 1997, inflows from the 14SE Headgate fault had decreased to approximately 200 gpm. Similar to the B East Mains fault, in September 1998, when the 14SE Headgate fault system was mined tlirough in the 14SE Tailgate, the headgate inflow dried and the inflow began in the tailgate entries along the down- dip expression of the fault. Total 1997 inflows from the B East Mains fault were approximately 161 acre feet and from the 14SE Headgate fault were approximately 504 acre feet. ' • Groundwater inflows aze primarily observed near portal azeas under low cover (less • than 300 feet) neaz drainages and are generally responsive to spring runoff. • The available data have not shown a measurable impact on springs or surface water strictly attributable to Fand/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 1994, CDMG approved a pemut revision (Jumbo Mountain PROS) for the West Ells Mine. Much of the information contained in the Jumbo Mountain Decision Document (CDMG 1994) regarding the current pemut area is directly applicable to the probable hydrologic consequences anticipated as a result of mining the Apache Rocks and Box Canyon pemut revision areas. The following quotations from the Jumbo Mountain (PROS) Decision Document apply to the current permit area, including the Apache Rocks and Box Canyon permit revision azeas. WWE comments are included on the relevancy of the quotations for the !Apache Rocks and Box Canyon permit revision areas. • 1.05-l40 Nmember 2004 PR!!