Senators return to Washington on Tuesday with plenty of housekeeping to take care of before the 115th Congress comes to close.

Before getting to leadership elections and greeting incoming Senate colleagues, the current class has some legislating left to do. First up is a long-stalled reauthorization of the Coast Guard.

Before recessing for election season, Senate Majority Leader Mitch McConnell set up a vote for Tuesday evening to limit debate on the bill, which has been held up over complaints from Democratic lawmakers from the Great Lakes over Coast Guard authority to regulate the release of the water that is used to balance out boats.

South Dakota Republican John Thune, the Commerce Committee chairman, and Delaware Democrat Thomas R. Carper, the ranking member of the Environment and Public Works Committee, announced an agreement on final compromise language, which appears to give the EPA a role in working with the Coast Guard on crafting the new policy.

“This agreement to have the Coast Guard enforce standards established through an EPA-led process will create needed clarity for vessel operators while remaining sensitive to local concerns about invasive species,” Thune said in a statement. “I appreciate Sen. Tom Carper for working with me on this important issue. This language is a victory for both the environment and commerce.”

Watch: The Border Wall Funding Fight Could Lead to Another CR, or Partial Federal Shutdown

When McConnell, a Kentucky Republican, first called an earlier version of the reauthorization up for a vote in April, Democrats led a blockade, with many citing the vessel incidental discharges provision.

The primary concern centered around the potential for water discharged to exacerbate the spread of invasive species, such as the Asian carp. The deal between Thune and Carper seeks to address those concerns.

“This bipartisan compromise strengthens ballast discharge standards in an environmentally protective way. Specifically, it will reduce the risks posed by ballast water discharges that enters our waterways, minimize the likelihood of introducing invasive species along our coasts and in the Great Lakes, while still ensuring these discharges are regulated under the Clean Water Act,” Carper said in a statement. “This bill shows that we can keep our vessels moving in and out of our waterways while protecting our environment and marine life at the same time.”

Wisconsin Democrat Tammy Baldwin, who led the opposition to the earlier April bill that failed to get the 60 votes needed to advance, was reviewing the final agreement as of Monday afternoon.

McConnell has portrayed the provision as a bipartisan effort to provide regulatory clarity to the boating community.

He said on the floor earlier this year that “our vessel owners and operators have been saddled with uncertainty. They’ve faced a patchwork of overlapping, duplication regulations enforced by the Coast Guard, the EPA, and the states. This inefficient regulatory regime unnecessarily raises costs and jeopardizes jobs.”

With the deal, the Coast Guard bill will likely pass the Senate early Wednesday afternoon, after Senate Republicans spend the morning huddling in the Old Senate Chamber for the leadership elections for the 116th Congress.

That should hold few surprises, with the current Republican whip, Texas’ John Cornyn, term-limited out of the leadership ranks and others moving up. Thune is the anticipated next No. 2 in the Senate GOP leadership.

As for floor activity after the Coast Guard bill during the abbreviated week, McConnell already filed cloture to break a potential filibuster of Michelle Bowman of Kansas to fill an unexpired term on the board of governors of the Federal Reserve.

The Banking, Housing and Urban Affairs Committee advanced her nomination on an 18-7 vote in June.

Bowman is the state bank commissioner in Kansas and a fifth-generation banker at her family’s Farmers and Drovers Bank of Council Grove, Kansas. In 2015, Congress passed a law requiring one of the Fed’s seats to go to someone with “demonstrated primary experience” at a community bank. If confirmed, Bowman would be the first to hold the community banking seat at the Fed.

Doug Sword contributed to this report.