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Mr. Jim Burnell May 2, 2005 Page 2 Please note that the procedures utilized by MCC for permanent sealing of methane drainage wells as documented during my inspection of the abandonment procedures on June 1, 2004 aze compliant with DMG Rules and guidance document. I was both impressed and pleased with MCC's abandonment procedures during my inspection. The procedures I observed at several MDW sites included: • Placement of rubber bridge plug at the lowest point or until refusal in the blank well casing; • Running tremmie pipe into casing and determining depth of bridge plug; • Placing mixture of Hole Plug and water via tremmie pipe to a level approximately twenty feet above bridge plug and ensuring that gas flow to the surface has ceased; • Pumping approximately 100 feet of cement (Quick Crete) via tremmie pipe; • Filling remainder of hole to approximately ten feet below ground surface (bgs) with bentonite slurry; • Placing cement plug from ten feet bgs to within three feet of the surface and backfilling hole with dirt; and • Marking and surveying the hole. I recommend that the language presented on page 13 of the 2005 Annual Operating Plan be revised and updated to be more specific and to remove language that misquotes Rule 4.07.3. I have essentially the same comments regazding the submittal as my last yeazs review dated May 5, 2004. 1. Under the drill hole plugging methods page 13, it appeazs that MCC has misquoted our current Rule 4.07.3. MCC indicates that Rule 4.07.3 states "that each open hole will be plugged with cement from bottom to within 50 feet above the uppermost thick coal seam and from 50 feet below to 50 feet above any aquifers". Our rule makes no mention of the uppermost thick coal seam and our rule actually requires 20 feet of sealant above and below the water-bearing zone as an option in cases where holes have multiple aquifers. I recommend revising the first paragraph under DRILL HOLE PLUGGING METHODS to correctly quote our current Rule 4.07.3. 2. MCC also misinterpreted our surface plug requirement. Out rule requires placement of a suitable plug 10 feet below ground surface to support aseven-foot cement plug. MCC is proposing a 5-foot cement surface plug. However, ifthey fill the hole to within 5 foot of the casing cut-offpoint with approved materials and then place a 5-foot cement plug they would be compliant. 3. MCC has not specifically addressed whether or not these holes will extend to aquifers. There maybe some contention as to the definition of aquifer. If they do extend to aquifers then sealant must be placed in the hole from the bottom to within 10 feet of the surface. Alternatively, for holes with multiple aquifers the Division may approve a suitable media for placement twenty