Coal Tattoo readers know by now that Massey Energy held a closed-door meeting with the families of the Upper Big Branch miners at least in part to promote the company’s contention that the evidence is in on whether tampering with methane monitors played a role in the April 5 disaster.

Massey made it clear in the press release summarizing what it told the families:

Methane monitors at the longwall section had not been disabled.

Now, CEO Don Blankenship declined to talk with reporters after the meeting, and his general counsel, Shane Harvey didn’t get into details about the evidence Massey believes supports this conclusion.

State investigators have disputed the Massey conclusion, saying not nearly enough information is in yet to draw such a conclusion.

Ron Wooten, director of the state Office of Miners Health, Safety and Training, was kind enough today to walk me through some of the key evidence that has yet to be fully evaluated about the methane monitors in the longwall section.

(As an aside, understand that Massey is arguing that the explosion likely occurred in the longwall area, in part because that fits its theory that a sudden gust of methane inundated the mine from a crack in the floor in that part of the mine. One thing that Wooten added today is that investigators haven’t been able yet to examine the methane monitors on continuing mining machines in two other parts of the mine, because of dangerous conditions in those areas).

In an interview yesterday, Wooten explained that the longwall machine was equipped with a “black box” that recorded certain data — including readings from the methane detectors in that part of the mine — for up to six days.

Interestingly, Wooten said, Massey had replaced the “black box” on March 30, just less than a week prior to the April 5 explosion. Investigators aren’t yet sure why that was done. “They may have had a problem with another one or something,” Wooten said.

Another interesting thing is that investigators believe the clock on the “black box” was wrong .. that the time was off by just less than four hours. As I recall, there was a similar problem with the mine computers at International Coal Group’s Sago Mine prior to the 2006 explosion that killed 12 miners there.

Wooten said that a preliminary check of the data from the “black box” indicates no readings going back six days where methane in the longwall section went higher than 1 percent (the explosive range being between 5 and 15 percent).

But, it also indicates that, at 3 p.m. and 22 seconds on April 5, one of the methane monitors recorded a “loss of signal.” I thought perhaps that indicated the explosion had knocked out the equipment, but Wooten said investigators believe instead that a worker turned off the longwall machine — perhaps because it was time for shift change.

More importantly than all of this, though, is that MSHA and the state have yet to run a “functionality” test on the “black box,” which would tell them if methane monitors were properly recording readings and transmitting those to the box, and the box properly reading and recording them.

That test isn’t scheduled to be conducted until next week, Wooten said.

I also asked Wooten if —  aside from the now-widespread media reports about former Massey workers saying the company frequently “bridged out” or disabled methane monitors at Upper Big branch — government investigators have gathered evidence thus far that prompts them to want to look very closely at this possiblity … Wooten responded:

Yes.