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the No. 5 mine pump. During the last quarter of 2012, the pump failed, resulting in no discharge. The pump <br />is anticipated to be replaced in the spring of 2012. The former Okie Plaza Trout Creek well was abandoned <br />in June 1994 as mining advanced through its location. <br />The water levels in the Middle Sandstone formation as measured in wells TR -4, TR -7a, 81 -01, 83 -01, 83 -02, <br />and 83 -03 show fluctuations which are apparently related to dewatering and past subsidence associated with <br />Mines 5 and 6. Wells TR -4 water levels appear to be slightly rising since about 2008. Levels in TR -7A and <br />81 -01 in 2012 are relatively consistent with that seen in 2006 through 2009. The water levels in 83 -01 <br />(Figure 7) have been on the rise since monitoring was reactivated in 2006. The water levels in well 83 -02 <br />(Figure 8) are consistent with those found since monitoring was reactivated in 2006. The water level decline <br />of about 150 feet from 1987 to mid 1990 in well 83 -02 was determined to be related to mine dewatering as <br />Mine 5 workings approached the location of the well. The more abrupt 200 foot decline in water levels <br />observed in 1990 is thought to be a drawdown response due to subsidence as it is located only a few hundred <br />feet horizontally from an F seam longwall panel which was mined in a similar time frame. The water level <br />stabilized until 1994 when it recovered to the 1983 levels. <br />Wells TR -4 and 83 -03 are located at greater distance horizontally from the active operations for mines 5 and <br />6. Water levels in Well TR -4 (Figure 4) historically appear to be related to the fluctuations observed on all <br />three of the down gradient Middle Sandstone Wells: 81 -01, 83 -01 and 83 -02. The water level decline in TR -4 <br />prior to 1984 and the subsequent recovery up to 1988 closely parallels the trends observed in Wells 81 -01 and <br />83 -01. The decline during the first part of 1991 also parallels the trend in these two wells. However, the <br />rapid decline during the last part of 1989 and the first part of 1990 appears to follow the trend observed in <br />Well 83 -02 although the magnitude of decline is considerably less. Unusually large fluctuations for TR -4 for <br />1999 through 2000 have been attributed to a faulty pressurized line system. <br />Well 83 -03 (Figure 9) is the Middle Sandstone monitoring well located furthest (more than 1.5 miles) from <br />active underground operations for Mines 5 and 6. The overall trend from 1984 through 2000 and again in <br />2006 to date suggests a similar trend to the other Middle Sandstone wells. The long term decline could be a <br />pressure response due to the overall drop in potentiometric levels in the Middle Sandstone in the vicinity of <br />Mines 5 and 6. The water levels in the Middle Sandstone wells had either recovered or stabilized in 1995. <br />Note that in early 2008 and 2009 there were drops in the water level. The largest drop being approximately <br />25 feet in early 2009, after which water levels stabilized and started to rise again in 2012. The reason for the <br />drops is unclear. <br />Monitoring results through year 2001 and again in 2006 to date (Fig. 10) showed no apparent change in the <br />water levels in the Twentymile Sandstone that could be attributable to mining activities. During 2012, wells <br />259 and 84 -01 remained stable as compared to 2006 through 2010. 9 Mine well exhibited a rise in water <br />elevation, and has since started a slight decline. It's unclear if above average snow melt in the area had <br />temporarily recharged the aquifer. Note that in 2006 the first reading of the 9 mine well appeared elevated, <br />and subsequently leveled off and has been stable through 2012. The elevated reading may be attributed to an <br />error in monitoring equipment, as a pressurized reading was first attempted, and subsequent readings have <br />used a water level meter. <br />The groundwater gradient in the Middle Sandstone in the vicinity of the mining operation generally decreases <br />from the southeast to the northwest as reflected on Figure 11. The piezometric contour map of the <br />Twentymile Sandstone is presented as Figure 12. This gradient remains generally consistent with previous <br />Page 4 <br />G \Environmental\EMPIREWILLIAMS FORK \Water Permits & Re1ated\AHR\2012 \Empire2012AHR doc <br />