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system was to monitor progressive flooding of the mine and associated water <br />quality and to allow discharge of ground water in the unlikely event that water <br />levels were to reach the portal seals. Further evaluation determined that the <br />anticipated rate of mine flooding will be very slow, limiting the potential <br />effectiveness and value of the drain system. EFCI plugged and sealed the pipe <br />according to approved Minor Revision No. 52 (January 2004), and applicable <br />requirements of Rule 4.07.3. <br />Open drill holes, boreholes, wells, or monitoring wells exist at the mine site, and <br />remain to be sealed prior to final bond release. These holes were drilled by both <br />EFCI and its predecessor, Dorchester Coal Company (Dorchester), in <br />conjunction with the initial exploration and active development of the mine. The <br />open holes are typically monitoring wells that will be sealed when no longer <br />required for groundwater monitoring. In order to establish an accurate <br />inventory of any other unsealed holes, EFCI will perform a field reconnaissance <br />of documented drill holes and wells to verify the status of sealing and <br />reclamation. <br />EFCI will seal all open drill holes, boreholes, wells, and monitoring wells which <br />will not be utilized in conjunction with post-mining land uses. Since there are <br />no known aquifers in the mine area, permanent sealing of these holes will be <br />performed in accordance with Rule 4.07.3(1). Methods for sealing drill holes, <br />boreholes and wells are discussed in permit Sections 2.02 and 4.07, and as <br />follows: <br />o Backfill hole, from the bottom upward, with cuttings or other suitable <br />media, and place a suitable plug 10 feet below the ground surface to <br />support a cement plug or other approved media to within 3 feet of the <br />ground surface. <br />o For groundwater and monitoring wells only, establish a cement plug <br />from the bottom of the borehole extending through the completion <br />zone(s) to a point at least 20 feet above the uppermost zone of <br />completion. Backfill the remaining interval with cuttings orother suitable <br />material, and place a suitable plug 10 feet below the ground surface to <br />support a cement plug or other approved media to within 3 feet of the <br />ground surface <br />o Cut and remove any existing surface casing below final ground surface. <br />o Install hole marker. <br />2.0 5.4 - 3 0 Revised 10/04/07 <br />MR-55 <br />