2009-07-01_REPORT - C1980007 (6)

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West Elk Mine 2008 Annual Hydrology Report 67 • in monitoring Well RAV-4b, completed in the B-Seam, dropped sharply (about 36 feet) from 565.64 feet in September 2002 to 602.62 in April 2003. The water level remained relatively steady in WY 2004 (602.76-602.79 feet), and dropped again about 20 feet in WY 2005 to 622.8 - 622.9 feet. The water levels remained steady in WY 2006 (622.1 to 622.7 feet). The water level in WY 2007 was variable, ranging from 629.0 feet (April 2007) to 613.8 feet (August 2007), the highest level to date. The water level dropped about 6 feet from August 2007 to May 2008 and remained relatively stable throughout WY 2008 (ranging from 618.7 to 619.4 feet). The water level at RAV -4b is expected to rise in WY 2009. The following wells have collapsed or become obstructed so no water level data are available for WY 2008. The casing in Well SO.W.-1 collapsed between April and June 2002, so no water level data are available subsequent to WY 2002. In August 2008 the casing at Well SOM 23-H-2 became obstructed at 190 feet below top of casing; therefore, no water level data were collected in WY 2008. As a result of the obstruction, no future water quality or water level data can be collected from this site. No water level data are available for wells SOM-2-H (obstructed in 1999; no water level data subsequent to WY 1999), SOM-16-H (obstructed; no water level data subsequent to WY 1999), and 96-27-1 (casing collapsed, no water level data subsequent to WY • 1999), because the well casing is obstructed. The casing at well SOM-13 has been compromised since 2000, so no water level data are available for this site subsequent to WY 1999. The water level in well SOM-23-H-3 in WY 2008 ranged from 203.7 feet (June 2008) to 207.2 feet (August 2008). Water levels at SOM-23-H-3 averaged about 194 feet in WY 2007 but dropped to an average of about 205 feet in WY 2008, a difference of about 11 feet. The water level drop in the following six wells may be mining related due to the up-gradient diversion of surface water runoff in the area. Wells GP-3 and RPE-7 went dry in WY 2004 and have not rebounded through WY 2008. The shallow colluvial monitoring Well GP-4 went dry in WY 2002 and continued to be dry to nearly dry through WY 2008. Water levels in Well GP-6 dropped in WY 2008 from 32.9 feet in May 2008 to 49.1 feet in August 2008, a difference of about 16.2 feet. Water levels in GP-7 dropped in WY 2008 from 30.9 feet in May 2008 to 48.2 feet in August 2008, a difference of about 17.3 feet. Well RPE-1 and RPE-7 did not have enough water to collect a sample in WY 2008. Water levels in monitoring Well 1-11-01, completed in the B-Seam, rose from 264.50 feet in December 2001 to 259.85 feet in April 2002, but have generally dropped about 126 feet over the • ensuing 5 year period to 386.0 feet through August 2007. Water levels rose in WY 2008 and were 355.3 feet in May and 355.0 feet in May and August 2008. The water level lowering at this site is June 2009 HydroGeo, Inc.