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Wes[ Elk Mine 2001 Annual Hydrology Report 23 • Mine ventilation moisture (50 ac-fr) • Miscellaneous mine seepage and evaporation (20 ac-fr) • Drilling water (7 ac-ft) • Pond evaporation (22 ac-fr) • Runoff from surface operations\pond dischazge (119 ac-fr) • Total Outflow = 691 ac-fr The total volume of water entering the mine during WY2001 was 738 ac-fr versus a total outflow of 691 ac-fr, a net difference of 47 ac-fr. The discrepancy is due to water contained in the NW and NE Panels sealed sump storage. The water deficient is augmented from MCC's water rights at Lost Lake Slough and the Fire Mountain Canal. 5.0 ASSESSMENT OF MINE INDUCED HYDROLOGIC IMPACTS 5.1 SurFace Water MCC maintains a network of 17 stream flow gaging stations throughout the permit and lease areas, listed in Table 4. The locations of the stations aze shown on Map 2. Daily mean flow tables aze shown in Appendix A. Stream hydrographs are presented in Appendix B and water quality is in Appendix C. n U 5.1.1 Area Stream Water Quantity and Quality Mining activity has approached only two major drainages, Minnesota Creek and Deep Creek. Long wall mining approached the azea of the Minnesota Creek drainage in July of 1998 and Deep Creek in March of 2001. Stream flow and water quality data from both of these streams indicate that there has been no mining induced impacts to these surface waters. 5.1.2 North Fork of the Gunnison MCC discharges to the North Fork via sediment ponds (MB-2R and MB-4) and direct discharges to Sylvester Gulch from the mine water pumping facility (MWPF). The major caflons and anions of the pond discharge water are sodium and bicarbonate. The sediment pond discharge water is slightly alkaline with a pH ranging from 6.76 to 8.39, with TDS concentration ranging from 295 mg/1 to 610 mg/1. The major cations and anions of the MWPF dischazge water aze sodium and bicarbonate. The MWPF discharge water is slightly alkaline with a pH ranging from 7.87 to 8.92, with TDS concentration ranging from 2,214 mg/1 to 3,820 mg/1. • A salinity (TDS) loading analysis of the MCC's WY2001 dischazges was completed relative to the current North Fork Cumulative Hydrologic Impacts Analysis (CHIA) (CDMG, 1997). The CHIA Project n 00301 HydroGeo, Inc.