"This bill is far more likely to impede rather than improve our ongoing efforts to enhance mine safety," NMA President Kraig Naasz said, adding that operators are working to implement a measure passed last year and this legislation would enact additional requirements and overturn others in the 2006 bill.
Democrats, however, heralded the measure as a much-needed improvement to mine safety laws in a year that so far has seen 25 coal miners and 28 other miners killed on the job. Six of those miners and three rescue workers died in two separate cave-ins at Utah's Crandall Canyon mine in August.
House Education and Labor Committee Chairman George Miller, D-Calif., said the legislation is a comprehensive approach to minimizing health and safety risks to miners.
"Our aim is a simple one: We want to do everything we can to ensure that miners are able to return home safely at the end of their shifts," Miller said.
The bill passed the committee on a 26-to-18 party-line vote, with Republicans opposing the measure. Rep. Rob Bishop, R-Utah, voted against the legislation.
Among other changes, the bill would call for more oversight of retreat mining, a method used at Crandall Canyon mine, with specific focus on mines more than 1,500 feet underground.
Retreat mining involves removing pillars of coal holding up the ceiling and allowing the roof to collapse, a process critics say is dangerous and may have led to the Utah disaster, which occurred 1,900 feet underground.
The United Mine Workers of America said the bill's passage was a "huge step" in the right direction for the health and safety of miners.
"The American public has seen for itself - far too often over the last two years - just how bad safety conditions in some coal mines in this country can be, and just how callously some coal operators disregard the mine safety laws that are already in place," said union President Cecil Roberts.
The Supplemental Mine Improvement and New Emergency Response Act shows that the House committee is listening to the public, Roberts said, not those who say enough has been done and Congress must back off for a while.
"Clearly, enough hasn't been done," he said. "Miners are still dying."
The committee's ranking Republican, Howard "Buck" McKeon of California, said his fellow party members grieve for the fallen miners but this legislation isn't about Crandall Canyon.
He said it was an attempt by the Democrats to rewrite a law just passed and not yet fully implemented.
"Despite the early successes of the law, my colleagues have proposed undoing the progress that has been made by layering on a new set of regulations and requirements," McKeon said, adding that the legislation has "the potential for serious negative consequences."
The head of the federal Mine Safety and Health Administration also expressed concern about portions of the legislation.
While the agency backs some provisions, those are "offset by potential harm" in the bill, MSHA director Richard Stickler said in a letter to the committee.
Bishop, the only Utah member on the committee, said he voted against the bill "because it's bad" and takes "everything to an extreme." Last year's Mine Improvement and New Emergency Response Act is just being put into place and shouldn't be amended before it can start working, he said.
"It's hard to find something positive about this thing," Bishop complained after the hearing. With 11 different bodies - including three congressional probes - looking at the Crandall Canyon disaster, Bishop says there's no need to rush to pass laws when the tragedy has yet to be fully explored.
The legislation also creates an ombudsman for miners to hear concerns from whistle-blowers who fear retaliation for speaking out. It allows, as well, MSHA to force a mine owner to comply with rescue operations.
The House committee recently heard from families of the victims of Utah tragedy who charged that MSHA did not do enough to protect them.
Republicans offered three amendments to the bill, including two that would have removed what Democrats said were key provisions to boost miner safety.
All three failed, with Bishop voting with his fellow party members.
The bill now heads to the House floor, though no vote has been scheduled. Sen. Edward Kennedy, D-Mass, has introduced a companion bill in the Senate.