Kline hammers Massey for 'systemic failure' to protect Upper Big Branch miners

Yet Kline also implied that existing safety laws are adequate, and took a jab at MSHA inspectors for not being tougher enforcers.

"As we have said time and again, the strongest laws on the books will not protect workers if those laws are not obeyed and enforced," he said. "We will continue to follow this ongoing investigation closely and work to ensure mine safety laws are being followed by mine operators and aggressively enforced by federal officials.”

Kline's position highlights the partisan disagreement over Congress' role in protecting miners in the wake of the UBB disaster. Democrats have urged adoption of tougher mine-safety rules, while Republicans have warned that new mandates on the industry would hobble job creation in Appalachia, among the most destitute regions of the country.

Mine-safety advocates have criticized the Republicans urging tougher MSHA enforcement, noting that the agency had been defanged under the George W. Bush administration. Bush, for instance, instituted a policy of “compliance assistance” at MSHA, under which inspectors were encouraged to point out safety hazards and help mine operators comply with the rules, rather than punishing safety violations with fines and other penalties. 

MSHA's newly announced findings – the result of a 15-month investigation into the blast – charged that Massey failed to control highly flammable coal dust and didn't maintain water sprays. The company put an “emphasis on productivity to the detriment of safety,” the agency added.

"This explosion could and should have been prevented by the mine operator," MSHA said. 

MSHA's findings are strikingly similar to those reported in May by an independent investigative team. Led by former MSHA administrator J. Davitt McAteer, that group of experts found that Massey failed to maintain its ventilation system and allowed coal dust to accumulate above legal limits.

“The company broke faith with its workers by frequently and knowingly violating the law and blatantly disregarding known safety practices while creating a public perception that its operations exceeded industry standards,” the May report stated.

Massey officials disputed the May report, arguing that the blast was caused by a surge in “methane-rich natural gas” – an event they say the company couldn't prevent.

Massey this month was taken over by Alpha Natural Resources, which says it's still examining the cause of the explosion.

While MSHA's presentation Tuesday represented a preview of their findings – not the final report – the agency made clear there was nothing preliminary about the agency's verdict.

"We are further along than this just being our theory,” said Kevin Stricklin, head of coal at MSHA. “This is our conclusion.”