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West Elk Mine 2002 Annual Hydrology Report • 5.3 Stock Ponds and USFS Water Resources Numerous stock ponds and USFS water resowces are located in the mining area. The USFS sites are summarized in Table 7. Locations of these sites are shown in Map 3. There was no reported water loss or water quality issue at any of these sites in WY2002. 5.4 Grouud Water MCC maintains a network of 19 monitoring wells throughout the permit and lease areas. Anew well 01-11-1 was added to the monitoring network in WY2002. This well is installed in the B- Seam and the baseline monitoring will continue through November 2002. The casings in several wells have collapsed in the past several years, likely the result of mining induced subsidence. These wells include SOM-45-H1 (Sept. 2002), SOM-2-H (Jul. 1999), SOM-16-H (Sep. 2000), 96- 27-1 (Apr. 2002), and SO.W-1 (Jun. 2002). Hydrologic data from these wells is suspect or not available. A summary of the well monitoring schedule is in Table 4 and well completion information is in Table 5. Locations of the stations are shown on Map 2. Well water level data and water quality information are presented in Appendix F and G respectively. 5.4.1 Water Quantity and Quality The water level in the shallow colluvial monitoring well GP-4 went up 2 feet in late WY2002, this is probably the result of mine released flows in Sylvester Gulch that occurred during the monitoring period. Wells SOM-45-H1 and SOM-45-H2 have been affected by the underlying longwall mining in Panel 13. These wells are completed in the barren member of the Mesa Verde Formation above the F Seam. The interburden between this horizon and the mined interval is about 800 feet thick. The well casing in SOM-45-H1 collapsed between June and September 2002 and the well is no longer functional. The water level in SOM-45-H2 continued to drop (--10 feet) in WY2002, compared to 40 feet in WY2001. The continued water level fall may indicate that ground water levels have not stabilized since mining operations ceased in this area in 2000-2001 or this may be a function of poor recharge due several years of drought. The casings in wells 96-27-1 collapsed between September 2001 and April 2002 and casing in well SO.W.-1 collapsed between April and June 2002. These wells are no longer functional. Water levels in SOM-76 have dropped during the last several years including during WY2002. • This is likely due to wet years in 1994 and 1995 followed by drought conditions through 2002. 26 Project # 00301 HydroGeo, Inc.