2009-07-01_REPORT - C1980007 (6)

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West Elk Mine 2008 Annual Hydrology Report 68 likely due to mining and water level raises are most likely due to post mining recharge and recovery. The water level in this well is expected to rise in WY 2009. The water level in monitoring well SOM-3-E has shown a generally continuous decline in water level from the time of installation in 2003 (965.43 feet), with the exception of a suspect measurement in September 2005 (939.0 feet). In WY 2008, the water levels ranged from 985.6 feet in June 2008 to 986.9 feet in August 2008, the lowest reading to date. The average water level was 963.5 feet (suspect), 981.7 feet, 982.4 feet, and 986.1 feet in WY 2005, WY 2006, WY 2007, and WY 2008, respectively. Excluding the suspect data from WY 2005, the average water level has dropped about 4.4 feet since WY 2006. The water level lowering may be the result of mining and possibly drought conditions in recent years. The water level in Well SOM 3-E is expected to fall in WY 2009, as mining in the E Seam progresses. Monitoring Well SOM-313, installed in the B-Seam, is located up-gradient of current mining operations. With a couple of exceptions, the depth to water in this well has continuously dropped from 1,142.66 feet in October 2003 to 1,198.3 feet in August 2008, a difference of about 55 feet. During WY 2007, thick mud lining the inside of the well casing prevented reliable deployment of the water level sounder. Water level recordings at Well SOM-313 were 1,197.4 feet in May and • June 2008 and 1, 198.3 feet in August 2008. The water level lowering may be the result of mining and possibly drought conditions in recent years. The water level in this well is expected to fall in WY 2009 as a result of the B-seam mining that was completed in the area. The water level in monitoring Well SOM 129-H has shown a rise of about 54 feet from September 2001 (275.75 feet) to April 2002 (221.50 feet), and another rise of about 45 feet from May 2005 (227.82 feet) to 182.0 feet in September 2005. The water levels in WY 2008 ranged from 53.6 feet (May 2008) to 149.0 feet (August 2008). The data for all of WY 2008 are suspect because at some time prior to May 9, 2008 the well casing was removed and runoff and precipitation water from the nearby drainage ditch along the road flowed freely into the well, compromising both the water level and the water quality in the well. The casing was repaired prior to the June 6, 2008 site visit so water level readings taken at future dates should be valid. Monitoring Well SOM 23-H-1 completed in the B-Seam, showed water level fluctuations of 40 feet during the baseline data collection period in WY 2005. In WY 2006 the water level rose over 30 feet. The casing of this well is believed to be compromised or broken and water levels may be influenced by shallow ground water inflows and are, therefore, not representative of potential impacts related to the B-Seam ground water zone. The casing in this well collapsed in 2006, most June 2009 HydroGeo, Inc.