Massey Energy Co. says a ventilation system ordered by government regulators reduced air flow in the Upper Big Branch mine, possibly causing the April explosion in which 29 miners perished.
Massey CEO Don Blankenship said that in 2009 and 2010, the agency required the mine to adopt a ventilation system that resulted in less airflow. He said this was in conflict with a 2004 MSHA report that called for increasing airflow and ensuring ventilation.
MSHA has maintained that Massey is responsible for all mine operations, including ventilation, and MSHA head Joseph A. Main told the Wall Street Journal that his agency was reviewing many records, including citations against the company for ventilation problems.
“While the air quality in the sections of the mine being worked six years ago may provide some insight, the team’s primary focus is on the circumstances occurring in the minutes, hours and months leading up to the investigation,” he said.
For over a week, a team of federal, state and Massey officials have been inspecting the mine, and federal prosecutors have launched a criminal probe into circumstances surrounding the explosion. Massey yesterday also announced that investigators had found a crack in the mine’s floor that had potentially leaked methane gas and instigated the explosion.

