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Section 780.18(b) Continued. <br />the coiled tubing. The cement plug created by perforating the casing and <br />pumping cement grout under pressure will extend from the bottom of the <br />borehole to within 10 feet of the surface. For wells with an existing <br />cement collar, the casing will be perforated below the cement collar {2 <br />holes over ten feet). Cement will be pumped into the casing until surface <br />returns indicate voids have been filled. For wells that do not have a <br />cement collar, cement will be pumped into the annulus between the <br />casing and borehole as well as inside the casing. <br />8b) Boreholes where the wireline probe reached within 10-20 feet of original <br />depth or through the coal bed and where artesian conditions do not exist <br />- Same procedure as above except that after pumping a cement plug of <br />sufficient volume to fill the borehole to 50 feet above the top of the coal <br />bed (consistent with the 1979 U.S.G.S abandonment diagram), the coiled <br />tubing will be removed. The interval above the cement plug will then be <br />filled with heavy mud or cuttings to within 10 feet of the surface. The <br />same surface plugging considerations and procedures will then be <br />implemented. <br />8c) Boreholes where the wireline probe did not reach within 10-20 feet of <br />original depth or through the coal bed -Coiled tubing will be inserted into <br />the casing to the maximum depth indicated by the wireline probe. Drilling <br />fluid (water) will be pumped down the coiled tubing to try to clean any <br />accumulated sediment and debris out of the casing. The borehole will <br />then be probed again following flushing. If the wireline reaches to within <br />10 to 20 feet of original depth or through the coal bed, the procedures <br />outlined in 8a or 8b will be utilized, as appropriate. If flushing is not <br />successful and approximate original depth cannot be reached, the casing <br />will be removed by either pulling or drilling-out the casing. Once the <br />casing is removed, the open borehole will be sealed and plugged <br />consistent with the procedure outlined in 8a. <br />9) Any casing extending above the ground surface will be cut-off flush with or just <br />below ground level. Any casing or other debris will be collected and removed <br />from the site for off-site disposal in a municipal landfill. Any temporary mud pits <br />will be allowed to dry out, the <br />MR-37 <br />780-88c Revised -September 2002 <br />