CHARLESTON, W.Va. — The chief executive of Massey Energy Co. is changing tack on what caused the coal mine explosion that killed 29 miners in West Virginia, blaming it on natural gas rather than methane.
Don Blankenship told an investor conference Wednesday that company investigators have discovered the Upper Big Branch mine was inundated with natural gas, causing the nation's deadliest coal mine explosion since 1970.
Massey had previously said it was believed a crack in the mine floor let loose a dangerous amount of methane gas.
The federal Mine Safety and Health Administration has not dismissed the possibility that methane flooded the mine. But the agency has said the crack identified by Massey was not the source of gas in the mine that day. A preliminary MSHA report blamed a mix of methane and coal dust.