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<br />application currently under review. Given the recent events, that would not <br />seem to be prudent. I would recommend that we maintain adequate bond <br />for the portal sealing task, until we are confident that the closure as <br />repaired is adequate. I am not sure whether there is anything above and <br />beyond what MSHA has required, that we should have Powderhorn do at <br />this time, or whether we need to take any further action or investigation into <br />the adequacy of the portal backfill (other than closely checking the backfill <br />on monthly inspections). Dave and Sandy, please advise in this regard. <br />Thanks to all for your help (especially John). Let me know if any of you <br />have additional comments or recommendations. <br />John Barton's report <br />Powderhorn Coal North portal (Cameo mine) December 06, 2001 visit <br />Back filling was observed in progress upon arrival to the portal area. The <br />fan structure was partially buried with fill dirt and concrete fill had been <br />poured yesterday to seal the return portal due to a methane ignition and <br />fire. The fan structure had been partially removed previously. Gas readings <br />along the left (north) side of the fan structure indicated no methane. Gas <br />readings behind the fan structure (between highwall and structure) <br />indicated 0.4% methane. Gas readings along highwall at points where back <br />fill (dirt) meets the gunnite varied from 0.2% to 1.2% with meter within 1" of <br />gunnite. At mid point of highwall where a "crack" had been freshly back <br />filled readings averaged 0.6%. One area along right side of fan structure at <br />the sandwich joint against the highwall up to 3.7% was detected. In all <br />areas where methane was detected within about 1" of the structure or the <br />dirt, the methane readings would fall to 0.0% when the meter was <br />withdrawn by 6". Barometric pressure at time of return to office (1:OOPM) is <br />30.29 and falling. Meter used is Industrial Scientific TMX412 calibrated <br />Nov. 14, 2001. John C. Barton <br />