The federal government has a fund of $44.3 billion earmarked for spending on a permanent nuclear waste disposal facility in the United States.

It began collecting money from energy customers for the fund in the 1980s, and the money is now earning about $1.4 billion in interest each year.

But plans to build a site in Yucca Mountain, Nevada, were scuttled by state and federal politics, and there’s been a lack of political will to find other solutions. The result is that the U.S. does not have the infrastructure to dispose of radioactive nuclear waste in a deep geologic repository, where it can slowly lose its radioactivity over the course of thousands of years without causing harm.

However, with the effects of climate change becoming more obvious, investors and some political activists are renewing interest in nuclear as a source of energy that does not emit climate-warming carbon dioxide. That is forcing proponents to confront the thorny problem of waste again.

Congress established the Nuclear Waste Fund in 1982, requiring anyone who was getting some of their electricity from nuclear energy to pay a small amount of money to deal with the waste.

From 1982 through 1987, the Department of Energy explored nine sites for permanent waste disposal, and eventually whittled that list down to three. Yucca Mountain in Nevada was the first choice, with sites in Washington and Texas rounding out the top of the list. Some members of Congress were concerned that analyzing multiple sites would cost too much, and so in 1987, Congress amended its 1982 law to focus all of its attention on Yucca Mountain.

“Some would say Congress made a prudent choice, but other would say that Yucca was prematurely down-selected because the Nevada delegation had the least political clout on the Hill,” Rod McCullum, the senior director of decommissioning and used fuel at the Nuclear Energy Institute, told CNBC.

“Over time the latter view tended to prevail, and the 1987 Amendment is now commonly referred to as the ‘screw Nevada’ bill,” McCullum said.

The 1987 amendment also established a program to find a interim storage solution, Steve Nesbit, the President of the American Nuclear Society, told CNBC. Some of the Nuclear Waste Fund money was spent on that effort, but that project shut down in 1994 because it wasn’t working, Nesbit said.

In 2002, then-President George W. Bush signed a resolution establishing the Yucca Mountain repository, but Barack Obama campaigned against it, and ended up cutting funding for Yucca Mountain in his 2010 budget.

The political opposition in Nevada “probably wouldn’t have made a difference if Senator Reid had not become such a powerful political figure, but he did and he used his influence to stop the project,” Nesbit told CNBC. ”Unfortunately, Yucca Mountain, like so many things, has become a partisan issue, which makes it that much harder to get anything done.”

After 2014, the federal government was forced to stop collecting money for the Nuclear Waste Fund because of a legal ruling. Owners and operators of nuclear power plants had challenged Department of Energy’s collection of fees, arguing that ratepayers should not be paying into a fund when the United States had no viable options for where the used fuel permanent disposal should go.

Amid all the stops and starts, the money in the Nuclear Waste Fund has been put back into the general fund and is being used for other purposes, Frank Rusco of the Government Accountability Office says. To use the funds for their original purpose would require new authorization and appropriation by Congress, he said.

“This will potentially cause a difficulty in getting a repository built,” Rusco said.

Since the federal government has not established a permanent repository for its radioactive nuclear waste, it’s had to pay utility companies to store it themselves. Currently, nuclear waste is mostly stored in dry casks on the locations of current and former nuclear power plants around the country. So far, the system is working, and in 2014, the Nuclear Regulatory Commission (NRC), the lead oversight body for the industry, has said that current storage technology would be sufficient for 100 years.

“We’ve loaded over 3,000 of these systems since 1986. And we haven’t had we haven’t had a problem. And nothing’s gone wrong. No radiation has been released,” McCullum told CNBC.

“It should be noted that just because NRC assumed the storage systems would be replaced at 100 years, doesn’t mean they necessarily would be,” McCullum said. If a utility applies for a license from the NRC to go beyond 100 years, the NRC would have to revisit its analysis. “Fortunately we have until 2086 to figure that out. I certainly hope that disposal will be available by then.”

As of Sept. 30, the government has paid $9 billion to utility companies for their interim storage costs and the Department of Energy’s Agency Finance Report estimates it will cost another $30.9 billion until a permanent waste disposal option is completed in the United States.

That estimate could prove to be low, Rusco said.

However, the tide may be turning back toward finding longer-term solutions.

On Nov. 30, the Office of Nuclear Energy at the U.S. Department of Energy put out a formal “request for information” for a temporary, but consolidated, nuclear waste storage in the U.S.

Unlike a permanent storage facility, which involves digging deep into the ground, a temporary facility would simply keep all the dry casks together in one place, as opposed to distributed around the country. In some cases, the local nuclear plants have been completely disassembled — but the waste is still stored on site. Consolidating it would at least save on costs.

“Then it just takes one security force and one maintenance crew and one operations crew and on it, it would just be much more efficient,” Nesbit told CNBC. “What they’re doing is they’re trying to start small and eat the elephant one bite at a time instead of all at once.”

McCullum of the NEI says the slow pace of progress on a permanent storage solution is not a problem. “You’re designing something that’s going to be protected for millions of years. It’s okay if we take decades to figure it out,” he said.

Meanwhile, the surge in concern about climate change has created new momentum for advanced nuclear reactors, which promise to be safer and more efficient than conventional designs. That means there’s also renewed interest in figuring out the waste problem.

“The timelines for these things are quite long compared to what we’re used to an instant gratification world. But in general, I’m optimistic,” says Rob Howard, the national technical director for Integrated Waste Management based out of Pacific Northwest National Laboratory. He spent two decades of his career working on the technical side of Yucca Mountain, which had been the most widely touted potential site for permanent disposal.

Further, some of the extreme antipathy toward nuclear power seems to be dissipating, Nesbit said.

“That visceral concern, associated with all things, nuclear, is something that primarily arises from folks who grew up in the Cold War era, and the time frame of the 1970s, where the anti-nuclear movement was really feeling its oats,” Nesbit said. Younger people are “a lot more open to new and innovative ideas.”

Other experts believe DOE’s request for information on an interim solution is nothing more than showboating bureaucracy to forestall the inevitable creation of a permanent geologic waste repository in Yucca Mountain.

“It is all politics, sadly. This can be done. If it wasn’t for Nevada’s 6 electoral votes and Harry Reid we would be building the repository now,” said Andrew Kadak, a professor in the department of nuclear science and engineering at Massachusetts Institute of Technology, and a consultant for the decommissioning of nuclear power plants.

The National Association of Regulatory Utility Commissioners, a non-profit organization representing the state public service commissions who regulate the utilities, brought the stalled investigation of Yucca Mountain to court, arguing that DOE and NRC needed to complete the formal assessment they had started, political machinations not withstanding. In Aug. 2013, the U.S. Court of Appeals for the District of Columbia Circuit issued a decision directing the NRC to resume the licensing process for Yucca Mountain.

In May 2016, the NRC issued a final supplemental report on Yucca Mountain finding that that risks associated with proposed fears of groundwater contamination, one of Reid’s points of contention, would be “small.”

The recent move by the DOE to solicit feedback for finding a new location is a delaying tactic, said Kadak.

“Even if the consent-based-siting processes started, I don’t see any state volunteering,” Kadak said.

Yucca Mountain is the logical and best solution, Kadak said.

“If I was the president, I would suggest restarting Yucca Mountain, because it’s an acceptable site, it’s had the technical reviews by the NRC, it’s ready for licensing hearing,” Kadak said.

For now, however, Department of Energy is standing firm that Yucca Mountain is a no-go.

“The Administration has made clear that Yucca Mountain is not a workable solution. Congress has not provided any funding for Yucca Mountain in over 10 years,” a spokesperson for the Office of Nuclear Energy told CNBC.

Nesbit doesn’t expect that to change: “No telling what a Yucca Mountain vote would be today, but it’s a moot point — the political leadership would never allow such a vote.”