Wednesday, August 08, 2007

Not Again

As everyone knows by now, six miners remain missing after more than two days in a massive ground collapse at Genwal Resources' Crandall Canyon Mine, and the effort to get to them is not going well. It does, however, seem reasonable to hold out hope.

I'm relying mostly on the the Salt Lake Tribune, which is posting frequent updates and a running index of related stories.

Reports are that workers are drilling 2-inch holes from the surface to the area where the missing men are presumed to be. These could provide communication and supplies. Apparently the holes need go 1,500 feet in all. Such drilling is not a fast process, and sometimes long drill holes encounter problems or miss their target. We can hope for the best in this.

The latest in the Tribune is that the Mine Safety and Health Administration is deploying its seismic system for locating trapped miners. The story discourages to much optimism on that, quoting MSHA's review of it sown actions following the 2006 Sago mine explosion. MSHA then called the system: "old, outmoded, cumbersome and time-consuming to deploy." It has emphasized that the system has never saved a trapped miner.

MSHA failed to mention that the system has saved lives -- in seismic events. One case was after a massive earthquake in Mexico City, where MSHA's seismic detection team found people people buried alive in rubble several days after the catastrophe. I can't recall the year, but believe it was in the 1980's. The Mexican government later honored the MSHA employees for the rescues, including Jeff Kravitz, who still works in the agency's mine emergency operations division. The seismic system does have limitations, and might not have been useful at Sago, but to imply that it has never saved lives just isn't true.

MSHA had other potential motives for downplaying the value of the seismic locator system. At Sago, the agency was slow off the mark in getting the system to the mine site, and took criticism for the delay.

One thing that worries me, if the miners are alive, is that after Sago, MSHA and others turned away from teaching the classic advice to miners who are trapped, to pound on the roof and walls of the mine so that rescuers might detect their signals. At Sago, everyone was horrified to learn that the miners were pounding out signals, but no one was listening. If MSHA is listening at Crandall Canyon, would the miners believe it was any use to signal? The full procedure, which used to be taught, included listening for three shots from the surface, then pounding out a signal. Were these miners taught that procedure?

I also worry about the ground stability as the rescue effort progresses. In the deep western coal mines, ground pressures can be extreme. Mines have pushed deeper and faced tougher ground control problems as the easier coal has been mined already.
Even in normal mining, significant roof falls are not that uncommon. Normally, no one is hurt, but there is always that potential. The science of rock mechanics is complicated. An action in one part of a large mine can affect ground stability in ways that a non-specialist could not predict, and it can even be tough for specialists. A major collapse has the potential to cause an evolving chain reaction.

That said, I believe there's still hope. Crandall Canyon could come out like the Quecreek mine rescue in 2002 rather than like the Sago explosion last year. I'm encouraged that MSHA chief Richard Stickler has gone to the site. The agency also said it's making family liaisons available to the relatives of the missing, a great improvement over the Sago debacle. As in the Sago explosion, MSHA did not initially take the lead in informing the public through news media about Crandall Canyon. But MSHA is talking now, at least. In this respect MSHA seems to have recovered its understanding, enforced in last year's MINER Act, that the federal mine agency exists to serve the community, not the mine operator alone.

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