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Fina] West Elk Mine 2005 Annual Hydrology Report 39 • 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 concentration of 35 mg/1, compared to the maximum baseline value of 6 mgll; and phosphate concentration of 2.45 mg/1 compazed to the maximum baseline value of 0.4 mg/l. The Lower Dry Fork Alluvial Well had elevated iron levels (3.26 mg/1) compared to the maximum baseline of 0.51 mg/1, and phosphate concentrations of 1.61 mg/l, compazed to the maximum baseline of 0.03 mg/1. Well 03-11-1 had a slightly elevated conductivity levels (3,430 µmhos/cm), compared to the maximum baseline value of 2,730 µmhos/cm, a nitrate level of 2.44 mg/1 compared to the maximum baseline value of 0.21 mg/1, and a phosphate concentration of 0.43 mg/I, compared to the maximum baseline value of 0.09 mg/l. Well 96-2-2 had an elevated phosphate concentration of 0.89 mg/1, compazed to the maximum baseline of 0.1 mg/1. 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 are 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 Alluvial monitoring Well GP-4 went dry in WY 2002 and remained 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 azea Well SOM-45-H1 and Well SOM-45-H2 have been affected by the underlying longwall mining in Panel 13. These wells are completed in the barren member of the Mesaverde Formation above the F Seam respectively. 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 compazed 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 axe no longer functional. The water level in monitoring Well SOM C-76, installed in the F-Seam, has dropped over 30 feet since WY 2003, including a 15 foot drop observed in WY 2005. This is most likely the result of September 2006 HydroGeo, IItC.