The U.S. has more than 90,000 metric tons of nuclear waste that needs to be disposed, the vast majority of which is so-called spent fuel from commercial reactors, meaning it is no longer efficient for power generation.

Generally, all this waste is sitting where it was created: at 76 sites in 35 states. And while the tally of waste is only going to grow, there is no long-term national storage solution, and this month the Trump administration may have put the final nail in the coffin of a long-studied effort to build a permanent repository for high-level waste at Yucca Mountain in Nevada.

John Kotek, vice president of policy development and public affairs at the Nuclear Energy Institute, the lobbying arm of the U.S. industry, says NEI supports both a medium-term storage program and a permanent one using Yucca Mountain to hold the waste.

“We feel like there’s a role for both,” he says. “And in particular, there’s real merit in using interim storage as a way of clearing out shut-down plant sites.”

President Donald Trump thinks otherwise about the permanent waste site. His fiscal 2021 budget proposal released this month does not include funding for licensing of Yucca Mountain as a nuclear waste repository located about 100 miles northwest of Las Vegas, an abrupt reversal of his administration’s policy.

“Nevada, I hear you on Yucca Mountain and my Administration will RESPECT you!” Trump tweeted on Feb. 6, four days before the budget proposal was released. “Congress and previous Administrations have long failed to find lasting solutions — my Administration is committed to exploring innovative approaches — I’m confident we can get it done!”

The president is using Yucca to drum up Republican votes in the 2020 elections, says Nevada Democratic Rep. Dina Titus. “I think he’s looking at the numbers,” Titus says. “He sees this as a swing issue.”

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Hillary Clinton won Nevada in 2016 with 47.9 percent of the vote, compared with Trump’s 45.5 percent.

Rep. Jerry McNerney of California says he and fellow Democrat Bill Foster of Illinois have a meeting scheduled with Speaker Nancy Pelosi to discuss Yucca strategy.

“She’s going to sit down with us and go over what the options are, try and work out something,” McNerney says. “There’s some technology out there that might be helpful, but this is going to be a tough political fight.”

There are more than 76 commercial reactors in the U.S. that are idling with spent nuclear fuel on site, NEI says. The Nuclear Waste Policy Act of 1982 calls for waste to be stored deep in the ground, and amendments to that law bound the Department of Energy to study sites for such a repository in just one place: Yucca Mountain in the Mojave Desert.

While the Bush administration greenlighted storage at Yucca, the Obama administration reversed course and established a commission, which, in 2012, called for a “consent-based” process to the problem. McNerney and Rep. John Shimkus, an Illinois Republican, both want to see Yucca used to store nuclear waste, and they introduced legislation to send spent fuel to interim sites before moving it to Yucca. Neither bill has gotten a full chamber vote.

Nevada’s congressional delegation and governor firmly oppose Yucca.

“If we try to force this on a state, it’s not going to work,” McNerney says, adding that it’s difficult to get members together on this issue.

“The interim storage idea is OK,” he says. “But the people that want permanent storage don’t want interim storage. There’s just different factions of how to deal with it.”

An interim-storage pilot program worth $22.5 million and sponsored by Sens. Dianne Feinstein, a California Democrat, and Lamar Alexander, a Tennessee Republican, held some promise, but it was stripped out of the latest budget deal.

“That was a victory for us,” Shimkus says. “We’ve been trying to work with Feinstein and Alexander, and really the compromise is moved to long-term storage while you do interim.”

Shimkus, whom McNerney referred to fondly as the “Darth Vader of nuclear waste” for playing the often unpopular pro-Yucca role, says the two senators are holding up a breakthrough.

“This takes two senators to agree to a compromise, and that’s Lamar Alexander and Dianne Feinstein to accept the premise that you need long-term storage tied with interim, and we would be moving forward.”

Both senators are the top ranking members of their party on the Senate Appropriations subcommittee that oversees the Department of Energy.

“Lamar Alexander will say all the right things to people in the media that he supports Yucca Mountain,” Shimkus says.  But in a decade of watching the issue, Shimkus says he can’t point to any actual help Alexander has provided with Yucca.