A Senate bill to establish a fund for long-deferred repairs in the National Park System looks primed to receive enthusiastic passage through Congress and the White House, with bipartisan support and advanced administrative approval.

But Senators on the Subcommittee on National Parks warned their fellow congressmen at a July 11 hearing against the temptation of piling on other legislation, as doing so could threaten the bill’s passage at a crucial window of support.

“We have the right mix of policy, we have the right mix of bipartisan support, we’ve got an excellent product,” said Sen. Lamar Alexander, R-Tenn.

“Any time in the United States Senate, when you see a train moving that you’re sure will get to the station, you start throwing as much baggage on it as you can, because you want to get to the station, too. But if we try to put too much baggage, or maybe even any more baggage, on this train, we won’t get to the station, because this is a pretty big lift to start with.”

The bill would make inroads at addressing the $12 billion backlog of deferred maintenance at the nation’s national parks by creating a specific account within the Department of Treasury that would be filled with revenue from offshore energy and mineral revenue sources, such as royalties for offshore drilling.

The bill has outspoken support from many parts of the Trump administration — from Department of Interior Secretary Ryan Zinke to Office of Management and Budget Director Mick Mulvaney — which Alexander called “essential” to passage.

“The time is right, the bipartisan nature is right, the support of the administration is critical, and — echoing Senator Alexander — let’s make sure it doesn’t get loaded up with too many more other items,” said bill sponsor Sen. Mark Warner, D-Va.

According to a letter by the National Wildlife Federation President and CEO Collin O’Mara to the subcommittee, the bill is also part of a larger ecosystem of legislation to support conservation in the U.S.

“America’s National Parks and wildlife are inextricably linked — and we are confident Congress can address the significant challenges facing both. We urge the Committee to think of the Restore Our Parks Act as one leg of a three-legged stool that provides the foundation for conservation in America,” wrote O’Mara, encouraging the passage of the Restore Our Parks Act alongside the Recovering America’s Wildlife Act and the renewal of the Land and Water Conservation Fund.

“We are also extremely committed to the Land and Water Conservation Fund. I do not see this bill in any way competitive with that, and we need to move forward with a permanent reauthorization,” said Sen. Angus King, D-Maine.