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<br />David Berry <br />January 22, 1996 <br />Page 2 <br />Groundwater <br />1) A review of the monitoring well depth data presented in the AHR and in permit <br />Exhibit 25 shows differences in depth of hole for monitoring wells 8, 10, and 65. <br />These differences appear to be errors in data transfer from the original drilling <br />information. As you know, the monitoring wells were completed in exploration drill <br />holes developed by Dorchester Coal Company. EFCI has reviewed the drill hole <br />information and revised the data on Table 8 of the AHR accordingly. Revised Table 8 <br />accompanies this letter for your records. <br />2) Monitoring Well No. 8 (MW-8) has oil contamination within the well casing as <br />described on Page 2.05.6-53 of the permit. This contamination occurred during drilling <br />and casing operations in 1978. There is no available information pertaining to the <br />cause of the contamination in our files. <br />EFCI and its predecessor, Dorchester Coal Company, have monitored water levels in <br />MW-8 since 1979 in accordance with permit requirements. In addition, EFCI mined <br />through the well in 1993 as documented in the 1994 AHR. Based on field <br />observations, the well has collapsed to a point 336 feet below ground level. <br />Data collected at MW-8 provides information about downgradient groundwater <br />movement within the permit area. Groundwater occurrence and movement within the <br />permit area is described in Section 2.04.7 of the permit, and shown on Map 5, <br />Regional Hydrogeologic Map. Based on the hydrology information, Monitoring Well <br />No. 65 (MW-65) provides data of groundwater downgradient of MW-8. MW-65 is <br />sufficient to provide data about any impacts to groundwater downgradient of the mine. <br />3) Well levels were monitored twice during the 4th quarter of 1994, on October 27, 1994 <br />and December 19, 1994. The October measurements were a late monitoring for the 3rd <br />quarter. EFCI has since monitored the wells every quarter in accordance with the <br />permit. <br />Mine Inflow/ Water Balance <br />l) EFCI planned to discontinue use of the North Well by the end of December 1994 <br />following construction of an underground water handling system, breaching seals in <br />the 1 North section, and making mine ventilation changes. The preliminary water <br />handling system was in place by late 1994, and discussions continued with MSHA <br />seeking approval to breach seals and change ventilation. <br />