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West Elk Mine 2004 Annual Hydrology Report 36 • 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 (-3 to 5 feet) in WY 2004, compared to 80 feet in WY 2002 and 10 feet in WY 2003. The continued water level lowering indicates 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 to several yeazs of drought. Water levels in this well may continue to drop in WY 2005. The casings in Well 96-27-1 collapsed between September 2001 and April 2002 and the casing in Well SO. W.-1 collapsed between Aprii and June 2002. Both of these wells are no longer functional. The water level in monitoring Well SOM-76 dropped about 10 to 15 feet in WY 2004. This could be the result of mining operations in longwall panel 17 or possible climatic conditions. Since mining in panel 17 is completed, water levels may begin to rise in Well SOM-76. Monitoring Well SOM 129-H showed a sharp rise of about 50 feet in water levels early in WY 2002 and remained high in WY 2004. The cause of the water level change is not known and MCC • will monitor this situation carefully. Monitoring Well RAV-4b, completed in the B-Seam, showed a sharp drop in water level of about 36 feet in WY 2003, but has remained steady in WY 2004. This may be due to mining of the Panels 14, 15, 16, 17 and 22 and dewatering of the B-Seam. These panels are located up-gradient of Well RAV4b. The water level in this well will likely remain steady or could begin to rise in WY 2005. Monitoring Well 01-11-1, completed in the B-Seam, showed a rise in water level from November 2001 to April 2002, but has steadily dropped through September 2004. This may be due to mining of the Panels 14, 15, 16, 17 and 22 and dewatering of the B-Seam. These panels are located up- gradient of We1101-11-1. Water level in this well may continue to fall in WY 2005. No other monitoring wells showed significant water level changes during WY 2004. 6.0 ADEQUACY OF THE MONITORING PROGRAM Since 1999 the West Elk Mine hydrologic monitoring program has operated in accordance with Technical Revision No. 88 (approved in August 1999) and Minor Revision No. 208 (approved January 1998). The hydrologic monitoring program in WY 2004 remained the same as WY 2003 with the exception of adding five new monitoring wells (See Section 3.3). August 2005 HydroGeo, Inc.