CHARLESTON, W.Va. -- The April 5 explosion at Massey Energy's Upper Big Branch Mine was so large and powerful that it ripped through more than 2 1/2 miles of underground tunnels "in an instant," leaving debris, soot and roof falls that continue to hamper investigation teams, a special adviser to Gov. Joe Manchin said Wednesday.
"That's a tremendous amount of energy released relatively quickly, and it spread in a large area very quickly," said Davitt McAteer, a former top federal mine safety regulator leading an independent probe for Manchin. "All of this suggests to us that the forces at work are complicated, are severe and are large."
McAteer said investigators have questioned more than 125 witnesses, but still have 100 or more interviews to go. Underground evidence collection did not begin until late June, and crews probably need several more months to complete that work, McAteer said.
And, McAteer revealed, investigators were able to examine the Raleigh County mine's longwall section only Tuesday, and still haven't been able to visit two nearby collections of tunnels that are other likely spots for the explosion to have begun. Along with damage from the explosion itself, parts of the mine have filled with water since the blast and need to be pumped dry before investigators can examine them.
"It's slow," McAteer said of the probe's progress. "That's not comforting to the families. We know that. But we only have one chance to do this. We want to do it right."
McAteer said he had some hope that his independent report might be done before year's end, but separate reports from the U.S. Mine Safety and Health Administration and the state Office of Miners Health, Safety and Training aren't likely to be completed by then, officials said.
Such timing isn't necessarily that unusual in major coal-mining disasters. For example, MSHA did not issue its report on the Jan. 2, 2006, Sago Mine explosion until May 2007.