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Fina] West Elk Mine 2005 Annual Hydrology Report 38 LJ maximum baseline value of 564 µmhos/cm. Spring G-14 had a slightly elevated conductivity of 1,100 µmhos/cm, compared to the maximum baseline value of 682 µmhos/cm. Spring G-22 had a slightly elevated conductivity of 1,250 µmhos/cm compared to the maximum baseline value of 640 µmhos/cm, and TDS concentrations of 770 mg/1 compared to the maximum baseline value of 516 mg/l. Spring 15-1 had a slightly elevated conductivity of 1,430 µmhos/cm compared to the maximum baseline value of 1,120 µmhos/cm and TDS concentrations of 940 mg/1 compared to the maximum baseline value of 730 mg/l. These increased concentrations are most likely due to low flow rates during the sampling period in June 2004 and 2005 and are not believed to be related to mining operations. MCC will monitor the water quality of these springs to determine if any changes in water quality trends occur No mining-induced impacts to water quality or flows in the monitored springs are anticipated in WY 2006. 5.3 Impacts to Stock Ponds and USFS Water Resources u Numerous stock ponds and USFS water resources are located in the Project Area. The USFS water resource sites are summarized in Table 7 and shown in Map 3. There were no known water losses or mining related water quality issues at any of these locations in WY 2005. 5.4 Ground Water MCC maintains a network of 28 ground water monitoring wells throughout the permit and lease areas. Four existing monitoring wells were added to the monitoring program in WY 2005: wells 23-H-1, 23-H-2, 23-H-3, and 23-H-4. Baseline data for these wells were collected in WY 2005. A summary of the ground water well monitoring schedule is presented in Table 4 and the well completion data is presented in Table 5. The locations of the ground water monitoring wells are shown on Map 2. The well water elevation and depth to water data are presented in Appendix F and the ground water quality data are presented in Appendix G. The casings in several monitoring wells have collapsed in the past several years and are likely the result of mining-induced subsidence. These wells include SOM-45-H1 (Sept. 2002), SOM-2-H (Jul. 1999), SOM-16-H (Sept. 2000), 96-27-1 (Apr. 2002), and So.W-1 (June 2002). As a result, hydrologic data from these wells for WY 2005 are not available. 5.4.1 Impacts to Ground Water Quantity and Quality • In general, there were no significant water quality changes in the ground water monitoring wells during WY 2005. However, there were several minor changes noted in the Upper Dry Fork Alluvial Well, Lower Dry Fork Alluvial Well, well 03-11-1, well 96-2-2, and well SOM-3B. The September 2006 AydroGeo, Inc.