CHARLESTON, W.Va. -- Massey Energy continues to argue that the Upper Big Branch Mine Disaster could not have been anticipated or prevented, despite evidence of two incidents in 2003 and 2004 that match the company's theory of the April 5 explosion that killed 29 miners.
Massey CEO Don Blankenship on Tuesday touted what he called the "biggest discovery" of the company's own investigation, saying Massey experts think natural gas -- not methane -- fueled the blast.
At an investors' conference in New York, Blankenship said company officials believe natural gas from a reservoir below entered the Upper Big Branch Mine through a large crack in the mine floor.
"It illustrates that it's something unusual, that it's more likely than not that it came out of the floor, that it didn't come out of the normal mining process, and it's not something you would normally be guarding against," Blankenship said.
Natural gas is made up mostly of methane, but can contain other flammable gases, such as propane and ethane. While methane is liberated from coal seams during the mining process, natural gas can be located near mining operations in separate underground reservoirs.
Massey said Tuesday that gas emissions shortly after the April 5 explosion and more recent emissions from the longwall area of the mine showed the gases involved were more likely natural gas, as opposed to methane.
"Most often the industry in these situations has not been focused on the possibility of natural gas," Blankenship said. "So we think it's a big discovery and they'll be a lot more of that coming out over the next few weeks as we get some material ready to prevent that more broadly."
Blankenship did not mention the previous incidents in 2003 and 2004, when the Upper Big Branch Mine became inundated with gas from cracks in the mine floor. No one was injured in the previous incidents.