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Draft West Elk Mine 2005 Annual Hydrology Report 39 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 SOM3B. The Upper Dry Fork Alluvial well had a slightly elevated conductivity of 737 µmhos/cm compared to the maximum baseline value of 509 µmhos/cm, chloride of 35 mg/1 compared to the maximum baseline value of 6 mg/l, phosphate of 2.45 mg/1 compared to the maximum baseline value of 0.4 mg/1. Lower Dry Fork Alluvial Well had elevated iron of 3.26 mg/1 compared to the maximum baseline of <0.04 mg/1 and phosphate of 1.61 mg/1 compared to the maximum baseline of 0.03 mg/1. Well 03-11-1 had slightly elevated conductivity of 3,430 µmhos/cm compared to the maximum baseline value of 2,730 µmhos/cm, nitrate of 2.44 mg/1 compared to the maximum baseline value of 0.21 mg/1, and phosphate of 0.43 mg/1 compared to the maximum baseline value of 0.09 mg/1. We1196-2-2 had slightly elevated phosphate of 0.29 mg/1 compared to the maximum baseline of 0.033 mg/1 and well SOM-3B had a slightly elevated conductivity of 5,080 µmhos/cm compared to the maximum baseline value of 3,070 µmhos/cm. These values aze all suspect and there is no indication that these water quality changes are attributed to mining operations and no additional changes are expected in WY 2006. The shallow colluvial monitoring Well GP-4 went dry in WY 2002 and continued to be dry throughout WY 2005. Wells GP-3 and RPE-7 went dry in WY 2004 and did not rebound in WY 2005, even with higher than average precipitation. The water level drop in these wells may be due to the up-gradient diversion of surface water runoff in the area Well SOM-45-H1 and Well SOM-45-H2 have been affected by the underlying longwall mining in Panel 13. These wells aze completed in the barren member of the Mesaverde Formation above the F Seam respectivley. 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 dropping water level in SOM-45-H2 stabilized in WY 2005, dropping only 1 foot compared to 5 feet in WY 2004, 9.5 feet in WY 2003, 12 feet in WY 2002, 13 feet in WY 2001, and 34 feet in WY 2000. Ground water levels appear to have stabilized since mining operations ceased in this area in 2000-2001. Water levels in this well may remain steady or start to rise in WY 2006, due to natural recharge. The casing in Well 96-27-1 collapsed between September 2001 and April 2002 and the casing in Well SO. W.-1 collapsed between April and June 2002. As a result, these wells are no longer functional. September 2006 HydroGeo, Inc.