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Page 2 of 3 <br />Prior to obstruction of MW -NW the Division had identified the importance of establishing a <br />ground water monitoring point that intercepts the mine workings. In September 2002 EFCI <br />proposed to seal the North Dewatering well after the cessation of mining. At that time the <br />Division hydrologist recommended the North Dewatering well be used for groundwater <br />monitoring in order to measure the quantity and quality of water flooding the mine workings. <br />(September 25, 2002 letter from DRMS to EFCI). <br />EFCI submitted a revision, TR35, on September 7, 2003, proposing to convert the North <br />Dewatering well to a monitoring well, MW -NW. Monitoring of MW -NW was included in the <br />Hydrologic Monitoring Plan. TR35 was approved on October 6, 2003. MW -NW was approved <br />to monitor the mine pool water quality and quantity. <br />EFCI submitted TR40 on December 31, 2012. TR -40 proposes to raise the monitoring point for <br />MW -NW to coincide with the elevation of the current obstruction of the well. <br />MW -NW had been open to the mine workings in the 1St North section of the mine in the Red <br />Arrow coal seam. According to the approved hydrologic monitoring plan, Exhibit 25, the <br />completion interval for MW -NW is 360 -380 feet. The floor of the coal seam was recorded at 380 <br />feet at the location of MW -NW. EFCI provided information that the coal seam was 5.5 feet thick <br />at this location. Therefore, MW -NW would have been open to the mine workings at 374.5 feet <br />(below the top of the casing). Prior to MW -NW becoming obstructed, the Division concluded that <br />MW -NW was being monitored at 374.5 feet, which translates to 5860.5 ft. msl (mean sea level) <br />[mine roof elevation noted by EFCI]. MW -NW is currently the only ground water monitoring well <br />in the approved Hydrologic Monitoring Plan for the Southfield Mine that intercepts the mine <br />workings. <br />Rule 4.05.13(1)(a) requires that groundwater level infiltration rates, subsurface flow and storage <br />characteristics, and the quality of groundwater shall be monitored in a manner approved by the <br />Division, including but not limited to, specific points of compliance to determine, i) the effects <br />of surface or groundwater mining activities on the quantity and quality in ground water systems <br />in the permit and adjacent areas. <br />Rule 4.05.13(1)(e) states that monitoring wells used to fulfill the requirements of 2.04, 2.05 and <br />4.05 shall be drilled, cased, and completed in a manner designed to achieve the isolation of the <br />aquifer of interest, the integrity of the well, and the accuracy of all the monitoring data collected. <br />Rule 4.05.13(1)(e)(i) states that all equipment, including wells, used to measure, observe and <br />sample the quality and elevation of ground water in accordance with the approved monitoring <br />plan, shall be properly maintained and operated so that the data collected accurately represents <br />the aquifer or stratum being observed. <br />The Division maintains that the currently approved groundwater monitoring plan was approved <br />to monitor and provide groundwater quantity and quality information for the post- mining <br />condition. MW -NW is the only groundwater monitoring well in the approved hydrologic <br />monitoring plan that is finished in the mine workings. This well is an important part of the <br />groundwater monitoring plan. Raising the monitoring elevation of the well 19.2 feet would <br />