As we reported last week, an independent panel reviewing the Mine Safety and Health Administration's (MSHA) role in the 2010 Upper Big Branch mine disaster found that the agency "possibly could have prevented" the explosion that took 29 lives.

MSHA's regulatory lapses before the blast were under the spotlight again Tuesday during a hearing of the House Education and Workforce Committee.

"Some enforcement failures have plagued the agency for years and deadly mistakes are always followed with a pledge to do better," said Committee Chairman John Kline (R-MN). "Yet Upper Big Branch still happened. Tragedy strikes, promises are made, new laws are passed, and a broken enforcement regime goes on."

But Joe Main, the under secretary of labor for mine safety and health, again blamed the tragedy on Massey Energy, the owner of the mine at the time.

"The challenges MSHA faced in enforcement at [Upper Big Branch] were created by an operator that intentionally evaded the law and interfered with our efforts to enforce it," Main told the committee.

"Massey, not MSHA enforcement, caused the explosion," Main added.

Federal prosecutors have charged former mine superintendant Gary May with conspiracy to violate mine safety laws at Upper Big Branch. May has already testified against another Massey official and is scheduled for a plea hearing Thursday. He's expected to plead guilty as part of a plea agreement that requires his cooperation in an ongoing criminal investigation.

Committee Democrats and the president of the United Mineworkers of America (UMWA) defended MSHA and Main, an Obama Administration appointee and former safety chief at UMWA.

"MSHA needed to do a better job with the tools it had," said Lynn Woolsey (D-CA). "Massey exploited MSHA's weaknesses."

UMWA president Cecil Roberts criticized mine safety laws that make criminal prosecution of mining company officials and executives difficult.

"You have to write it into law that if people put miners in unsafe conditions it's jail time," Roberts told the Committee.

In a statement issued after the hearing, Committee chairman Kline conceded "Massey is ultimately at fault," but also said he is "disappointed that Administrator Main continues to downplay his agency's critical failures...It is long past time to stop making excuses..."

Next week marks the second anniversary of the Upper Big Branch tragedy and some Committee members noted Congress' failure to toughen existing mine safety law since the explosion.

Congressman Robert Andrews (D-NJ) also listed what he characterized as past congressional failures to give regulators and prosecutors tougher "tools" when responding to violations of safety laws.

"For 29 of our fellow citizens we've all engaged in an inexcusable failure," Andrews said. "We failed to give prosecutors the tools to convict people of serious offenses and have sufficient punishment when they do. I think we have a responsibility for not giving MSHA all of the tools and resources and personnel it has needed over time."

In fact, Andrews noted, Congress slashed MSHA's budget in the decade before the disaster and experienced inspectors and supervisors left the agency. The result, said Main, was a diminished enforcement force with little experience.

Ranking Committee Democrat George Miller of California called on his colleagues to enact languishing legislation that provides for tougher criminal penalties and stronger protection for miners who complain about safety.

"As long as Congress is going to insulate the mine owners responsible for illegal behavior, I don't care how many people we give MSHA to staff up," Miller said. "They are going to be playing on the short end of the field. That's just unacceptable."

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