Massey Energy claimed Monday that critical methane gas monitors on a longwall mining machine were not disabled before the deadly April explosion at its Upper Big Branch coal mine in West Virginia.
In a private briefing for families of the victims, company executives also repeated claims that the massive blast that killed 29 mine workers was caused by natural forces.
But officials managing two state investigations of the disaster say Massey's conclusions are premature and not supported by witness interviews and evidence gathered to date.
Methane monitors automatically shut off mining machines when methane gas approaches explosive concentrations. NPR first documented an incident before the blast in which a methane monitor was deliberately disabled on a continuous mining machine. A federal grand jury is investigating the incident, and several Upper Big Branch miners told NPR the practice was common in the mine.
The longwall mining machine is in the area hit by the blast, and investigators believe it is one of several possible ignition sources for the explosion. They have also been anxious to inspect the methane monitors on the longwall miner for possible tampering.
Meeting With Families
But in Monday's briefing at a Charleston, W.Va., hotel, Massey executives told relatives of about half of the victims that "methane monitors at the longwall section had not been disabled," according to a company news release.
The families were also told that "mine seals were still intact and not breached." That's a reference to seals that are designed to keep combustible methane gas from seeping out of mined-out sections of the mine and into the working sections. Methane occurs naturally underground and collects in areas already mined for coal.
Two weeks ago, Massey officials floated a theory that a massive and natural surge of methane hit the mine just before the blast. They cited cracks in the floor of the mine as possible sources of the gas. But they also acknowledged that the last methane readings taken before the blast showed near-zero concentrations of gas, and the high concentrations of methane were measured 5 1/2 hours after the explosion.
State and federal mine safety officials have also contended that the force of the explosion itself would blow out the methane seals isolating old sections from working sections. That could explain the elevated levels of methane after the blast.
Massey's claim that the seals are "still intact and not breached" supports the company's theory that the massive explosion was fueled by a natural infusion of methane gas.
But officials involved in two state investigations of the disaster are skeptical.
"We do not have information at this point to say that [the longwall methane monitors] have or have not been tampered with," said Ron Wooten, the director of West Virginia's Office of Miners' Health Safety and Training, in an interview with the Charleston Gazette.
"Our investigation has not concluded what [Massey] has concluded," said Davitt McAteer, a veteran mine disaster investigator who leads an independent team assembled by West Virginia Gov. Joe Manchin.
In an interview with NPR, McAteer said investigators have not yet fully explored the blast zone underground and have not been able to inspect the condition of all of the methane seals. Flooding has kept investigators away from two of the three areas considered possible sources of the blast.
"It's grossly premature to suggest they know the location of the ignition source and that the seals are intact," McAteer said. "That's absurd. We're not there yet."
McAteer also noted that investigators have not yet determined whether another mining machine was working in the vast area affected by the blast. The explosion traveled more than 2 miles underground, turning corners and killing mine workers deep inside the mine and close to the surface portal.
Little Information From MSHA
The disabling of methane monitors, McAteer suggests, "potentially involves [mining machines] other than the longwall. We haven't been enough places to know where other machines might have been operating."
Mining machines are considered possible ignition sources, especially if methane gas is present.
In a written statement, Massey General Counsel Shane Harvey said, "Massey Energy understands that we have an obligation to ensure that [Upper Big Branch] families are made aware of important facts as they [are] acquired."
Massey is generally the only source of information about the investigation of the explosion. Two weeks ago, McAteer briefed reporters on his investigation but only provided general information. Investigators for the Mine Safety and Health Administration have not discussed any findings. MSHA officials have instead focused on Massey Energy's litany of safety violations and citations before the blast.
MSHA did not directly address Massey's latest claims in a statement issued in response to an NPR request for comment.
"The issues cited by Massey Energy are issues that remain under investigation by MSHA," the statement said. "The investigation is ongoing, and it's premature to reach any conclusions as to causation."
MSHA did not respond to direct questions about the status of the methane monitors on the longwall mining machines and the methane seals in the area hit by the blast.
Thursday marks the fifth month since the explosion, which was the nation's deadliest coal mine disaster in 40 years.