WASHINGTON -- The House of Representatives is moving swiftly in the wake of the April 5 explosion at Upper Big Branch coal mine to pass mine safety legislation, with a bill markup scheduled for today.

But the Senate, a graveyard for several House Democratic initiatives in this Congress, is taking its time to find a bipartisan consensus and will take up the bill this fall at the earliest.

A joint House-Senate "discussion draft" of the legislation was introduced last month by Sen. Tom Harkin, D-Iowa, and Rep. George Miller, D-Calif. It was later named for the late Sen. Robert C. Byrd, D-W.Va., a fierce mine safety advocate.

The bill would expand the ability of the federal Mine Safety and Health Administration to shut down problem mines along with increasing criminal penalties for violating safety law and making it easier to prosecute officials higher on the corporate ladder for creating unsafe conditions.

It also expands beyond mining to give more whistle-blower protections to workers in all fields -- provisions unsuccessfully sought by Democrats in the past.

Top Republicans on the Senate Health, Education, Labor and Pensions Committee and the House Education and Labor Committee chafed at not being included in the drafting of the bill, and criticized it for being overbroad and hasty.

Mr. Miller appears to be pressing ahead, while Mr. Harkin is engaging Sen. Mike Enzi, R-Wyo., in trying to write a consensus bill. A Harkin aide and Mr. Enzi said the discussions likely won't be complete until after the August recess.

"I think we're starting the right way by going back and listing out the principles we're trying to do and then plugging in the details," Mr. Enzi said.

"If you get in too much of a hurry on these kinds of things you end up with unintended consequences, too."

Mr. Enzi said he is not opposed to changes in the Occupational Safety and Health Act, which were roasted by Republicans at a House hearing last week, but he would like to spend more time crafting them, considering that OSHA covers everything from dentist's offices to oil rigs.

The bill would expedite the hearing process for whistle-blowers in all workplaces and allow them to pursue their own cases even if the Occupational Safety and Health Administration declines them. It also increases penalties against employers.

Mr. Enzi noted that the 2006 MINER Act, passed after the Sago disaster, was the result of bipartisan talks among himself and Sens. Johnny Isakson, R-Ga., Edward M. Kennedy, D-Mass., and Jay Rockefeller, D-W.Va. The bill passed the Senate by unanimous consent.

"That's what happens with good bipartisan legislation," Mr. Enzi said.

In early 2008, a follow-up mine safety bill -- from which much of the current draft legislation is derived -- died without even getting a committee hearing in the Senate, the victim of a lack of GOP support and a threatened veto from President George W. Bush.

Mine safety advocates have cited that failure as a reason to press ahead as fast as possible -- as political will wanes when the disaster recedes further into the rearview mirror.

Mr. Miller at last week's House hearing called the legislation "urgent."

"While it will take months to determine the precise cause of the Upper Big Branch explosion, we already understand the disastrous results when a mine owner operates on the margins of safety in order to put more coal on the belt," he said.

"Further study and investigation isn't needed to understand the result when workers' voices are silenced by fear of retaliation for speaking out on safety problems. And we know the consequences for safety when an operator repeatedly disregarded safety and does everything to avoid tougher oversight.

"Miners die."

Washington correspondent Daniel Malloy writes the "Pittsburgh On The Potomac" blog exclusively at PG+, a members-only web site of the Pittsburgh Post-Gazette. Our introduction to PG+ gives you all the details.