By Laura Litvan

Bloomberg News

WASHINGTON — Republicans in Congress plan to deploy a powerful tool soon after Donald Trump is inaugurated to scuttle a host of rules put in place in the last months of Barack Obama’s presidency, yet they must act quickly for the tactic to work.

A number of rules will be targeted using the Congressional Review Act, a law passed 20 years ago after Republicans took House control for the first time in four decades that provides an expedited procedure for canceling rules issued in the final months of an administration. It’s been used successfully only once, and top GOP lawmakers say they have about four months to act.

The regulations facing repeal includes a measure unveiled Monday by the Obama administration to protect streams and groundwater from pollution caused by coal mining. Senate Majority Leader Mitch McConnell said hours later he’ll introduce a resolution next month to overturn a rule he called a “regulatory assault” on the coal industry in his home state of Kentucky.

Other targets include rules enacted this year that would blacklist federal contractors with labor-law violations, make it harder for companies to avoid paying some taxes, and boost energy-efficiency standards to cut greenhouse-gas emissions.

“During just the first six years of the administration, federal regulators added an average of 81 new major regulations per year, or nearly 500 in total,” said Mike Long, a spokesman for House Majority Leader Kevin McCarthy of California. “We need to unshackle job creators from this mess of over-regulation.”

Congress has until early May to act, according to Senator John Barrasso of Wyoming, who leads the Senate Republican Policy Committee. This month, he released a list of almost a dozen rules that Senate Republican leaders see as top targets.

The House is likely to make a rules rollback a top priority next month, although there’s no agreement yet on the details and whether each rule will need its own vote on disapproval, Long said. The Senate isn’t ready to announce a plan, said Don Stewart, spokesman for McConnell.

A fast-track provision limits Senate debate on disapproval resolutions to 10 hours, and members could agree to a shorter debate period. Still, Randy Johnson, a senior vice president at the U.S. Chamber of Commerce, said a lack of time in the Senate may be the biggest challenge.

The Senate will be rushing to confirm Trump’s Cabinet, begin rolling back the Affordable Care Act and voting on other legislative priorities. Leaders also may determine they have to pass a separate resolution of disapproval for each rule, Johnson said.

The Congressional Research Service said it views the law as requiring each rule to be voted on separately, though the House and Senate parliamentarians would be the final arbiter on such questions. Combining multiple rules into a single vote in a bid to save time could also have a downside, since that would risk sinking the effort if a few of the 52 Republican senators don’t agree on the entire package.

The review act requires agencies to submit major rules to Congress, and lawmakers have up to 60 congressional working days to overturn them. A “reset” period at the beginning of a two-year session, combined with a new president, can let lawmakers torpedo the previous president’s most recent rules.

Republicans also are urging Trump to make a much broader effort to scrap or rethink a long list of regulations. Members of the conservative House Freedom Caucus sent a wish list of more than 200 federal rules for Trump’s consideration, governing matters as diverse as ending the U.S. Export-Import Bank and axing new ceiling-fan energy-efficiency standards.

“When the American people spoke on Nov. 8, they provided conservatives with an opportunity to restore order in our government and to remove the out-of-control bureaucratic red tape that so often stunts the growth of otherwise successful Americans,” said Representative Mark Meadows of North Carolina, who leads the conservative Freedom Caucus.

The Congressional Review Act has been used successfully once, when Congress ditched a workplace ergonomics safety rule in 2001. It was issued under Democratic President Bill Clinton in November 2000 and dispatched months later under Republican President George W. Bush and a new Republican Congress. Congress passed five other resolutions to disapprove rules, and all were vetoed by Obama.

UNIFIED CONTROL

Republicans’ unified control of the White House and Congress in 2017 means that not only can Republicans count on Trump to sign disapproval resolutions he receives, but it takes only a simple majority in the House and Senate to pass them.

Democrats warned that Republican moderates would be taking political risks by voting to dismantle environmental and consumer protections.

“They’d be voting to let Wall Street run wild, to allow companies to evade their taxes, and to make the environment less safe,” said Matt House, spokesman for incoming Senate Minority Leader Chuck Schumer of New York. “Republicans have the votes to erode these protections, and they’ll be the ones to bear the blame if they succeed.”

FEDERAL CONTRACTORS

Barrasso’s target list of rules to be rescinded includes one issued in August that requires federal contractors to report violations of up to 14 labor laws to the federal government, and risk losing out on further government work if they’re out of compliance. In October, a federal judge in Texas temporarily halted it hours before it was to take effect.

Others include energy-efficiency rules governing dehumidifiers, battery chargers and ceiling fans that are part of Obama’s climate-change strategy, and a Treasury Department rule designed to stop U.S. companies from shifting income overseas to curb their tax liability.

Republicans are thinking ahead to other regulations Obama might still try to complete before he leaves office, including a pending rule barring states from blocking funds to Planned Parenthood.

In the House, Republican leaders have a more expansive list of almost 50 rules that the Congressional Research Service says were issued by the Obama administration since a point in the summer when the review act’s clock would start. It includes Interior Department rules governing oil drilling on the Arctic outer continental shelf; new employee sick-leave requirements for federal contractors; and a crackdown on Wall Street banks’ ability to evade Dodd-Frank Act restrictions by moving some swaps trades overseas.

CHAMBER OF COMMERCE

Johnson, of the Chamber of Commerce, said the review act bars agencies from reviving any regulation overturned by Congress without a law permitting it to do so. For business, he said, that would be particularly helpful in the case of the contractor blacklisting rule, a perennial goal of organized labor.

Meanwhile, the clock already may have run down on one of Republicans’ top targets, a new overtime rule geared toward steering extra pay to as many as 4 million U.S. workers. While the House cast its last votes of the year on Dec. 8 — within 60 legislative days of when that Labor Department rule was published — other House pro forma session days this month have pushed it beyond the deadline.

One House Democratic aide who requested anonymity said the House parliamentarian has ruled that the overtime rule now falls outside the review act’s 60-day window.