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West Elk Mine 2004 Annual Hydrology Repon 34 • Table 11 Summary of Salinity Loading in the North Fork of the Gunnison Average Maximum Flow Calculated Scenario Continuous Weighted TDS Annual Salinity Percent of Discharge Rate Concentration Loading CHIS Loading (gpm) (mg/I) (tons/year) WY 2004 231 1751 1163 4% WY 2004 248 1882 1176 4% 2003 CHIS 5520 2500 30,159 -- t. Ustng t;UYJ volumes 2. Using Genera] Mine Water Balance Estimates 3. Based on maximum permitted discharge rate No mining induced impacts to water quality or flows in the North Fork are anticipated in WY 2005 because mine discharges are not expected to increase and the discharge water quality is expected to remain the same. 5.2 Springs and Seeps MCC routinely monitors 24 springs and seeps, listed in Table 3. Hydrographs of spring and seep flows aze presented in Appendix D, and flow and water quality data are in Appendix E. 5.2.1 Impacts to Water Quantity and Quality Spring and seep flows in WY 2004 continued to be below normal compared to historical averages, due to several years of below normal snow pack and precipitation. However more springs were wet or flowing in WY 2004 than in WY 2003 (Appendix D). A number of the spring monitoring stations have been dry for over a yeaz including Seep E-14-1 and Spring G-35. Several springs do not flow but are typically wet in the spring season. These include Spring G-26A, Spring G-28A, Spring G-lA, Spring 15-1, Spring 10-1, Spring E10-2, Spring 11-2, and Spring G-30. These springs have been impacted by lowered ground water levels due to continued multi-year extreme draught conditions. There is no indication that the reduced flows were the result of mining activities. Water quality data from WY 2004 did not indicate changes from baseline conditions for most of the monitored springs. Elevated TDS and conductivity values were noted at Spring G-7, Spring G-14, Spring G-22, Spring G-24, Spring 26-1, Spring 27-1, Spring G-49a, Spring G-25, Spring J-4. These increased concentrations are most likely due to low flow rates during the sampling period in . June 2003 due to regional drought conditions and are not believed to be related to mining operations. However, MCC will monitor the water quality of these springs to see if any water August 2005 HydTOGeo, Inc.