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EFCI Southfield Mint - 2014Annual Hy"ogy Report February 12, 2014 <br />Monitoring wells MW-7A, MW-7B, MW-8, MW 10, and MW-22 were previously included in the <br />monitoring program, all were subsequently mined - through and eliminated from ongoing <br />monitoring. Of these wells, MW-7A, MW-7B and MW-22 were mined - through, and monitoring <br />discontinued, by Dorchester Coal Co. prior to EFCI ownership in 1985. EFCI later mined- through <br />wells MW-8 and MW-10 during approved mining operations. All of the above referenced <br />abandoned wells were surveyed, marked, and sealed in September 2014 as part of EFCI's ongoing <br />reclamation activities. Additional information about the sealing of open boreholes can be found in <br />the Southfield Mine 2014 Annual Reclamation Report. <br />Wells MW-16, MW-23 and MW-65 were developed by Dorchester Coal Co. and have since been <br />monitored regularly. Well MW-NW was approved as a monitoring well in 2003; it was formerly a <br />dewatering well structure developed into Southfield mine workings in the Red Arrow Coal seam. <br />Well MW-16 water level data (Figure 1) indicate significant cyclic /seasonal fluctuations prior to <br />2001. When mining operations ceased in 2000, development of the mine had completely <br />surrounded the well location, possibly depleting the localized water table. The well was essentially <br />dry beginning in December 2001 until June 2004. Over time the well has silted -up to <br />approximately 110 feet below ground surface leaving 4 feet of perforated casing above the current <br />depth. Water levels during 2004 through 2005 were between 97 and 106 feet but the well has been <br />dry from 2006 through the reporting period. <br />Well MW-23 water level data (Figure 2) demonstrate steadily declining water levels since July of <br />1984. A slight increase in water level was measured from 2010 through 2011, then continued <br />declining levels through the period of this report. <br />Well MW-23 quality data (Table 5) depict values of dissolved calcium, chloride, and magnesium <br />above the average values for all quality data obtained since 1979. The sample data value for all <br />three parameters were, however, below historic maximum values. According to these data, chloride <br />and calcium values have been slowly increasing since 2006, whereas magnesium values have <br />gradually increased since 2008. Further review of the data show a highly elevated value of nitrate - <br />nitrite, as N, for the sample obtained in December. This abnormal value may have resulted from <br />sample contamination or laboratory error. All other tested parameters were close to, or below, <br />historic average values. EFCI will continue to monitor trends by continued sampling of the well in <br />accordance with the monitoring plan. <br />Well MW-65 water level data (Figure 3) exhibit generally stable values beginning in 1987. These <br />values display minor fluctuations of approximately 5 feet, from an average level of 280 feet, from <br />1987 through 2014. <br />Well MW-65 quality data (Table 6) indicate an increase in the amount of nitrogen ammonia for both <br />samples as compared to the average value for data obtained since 1984, but still below the <br />maximum value sampled in 2003. The data suggests an increasing quantity of this parameter <br />beginning in 1996. All other tested parameters were near or below historic average values. <br />2014 AHR tWLd00 Page 6 <br />