At shrinking Bonneville Salt Flats, land speed racers worry it’s the end of an era

Land speed racers and car enthusiasts gathered at the Bonneville Salt Flats for World of Speed last month, as they have nearly every year for the past four decades, greeting many longtime friends and familiar sites.

Plenty of famous cars made their return, like the Royal Purple streamliner that has reached speeds over 400 miles per hour, and the Cat Zilla 2, powered by two Arctic Cat snowmobile engines. And while dozens of international racers queued up to see how far they could push their limits, Allison Volk Dean, chairman of Save the Salt, said the event felt as intimate as ever.

“Everybody out here is like a big family,” she said.

But a key part of the races has become increasingly harder to find — the flats’ famous salt crust.

“It used to be all white right here,” said Volk Dean, gesturing toward a muddy expanse at the salt flats’ entrance site. “This year is significantly worse than any year I’ve been out here.”

The racers say they’re positive they know where all the salt went — on the other side of Interstate 80, collecting in the evaporation ponds of the Intrepid Potash mine.

“The sad part is, they’ve mined it off, but they haven’t mined it for salt,” said Dennis Sullivan, chairman of the Utah Salt Flats Racing Association, who has set records driving his 1927 Model T roadster. “They’ve mined it for potash. The salt is tailings to them.”

Potash is used in fertilizers to produce food. Companies have extracted it from the Bonneville Salt Flats since World War I, when Germany stopped shipping the material to the U.S. and its allies.

Representatives for Intrepid did not respond to requests for comment. But much of the latest research on the salt flats appears to support the racers’ hunch.

“All our estimates suggest that they have at least 100 million tons of halite [salt] on their property,” said Mark Radwin, a geologist with the Utah Geological Survey, of the mining operation. “Potentially up to 300 million tons or more.”

Radwin’s own research, conducted while he was a PhD candidate at the University of Utah, found the Bonneville Salt Flats have shrunk by around 75% in the last century. There’s still salt there, a couple feet thick in places, but it’s mixed with gypsum minerals, giving it a muddy appearance. What the racers need is a crust of snow-white halite — the same salt used on food or to melt ice, which gives the flats their distinct, other-worldly appearance.

The upper halite crust used to be a foot thick, the racers say. But it has become so thin in places it heaves and buckles, making it useless.

“This is what you have for salt now,” Sullivan said, prying up a hunk of halite about as thick as his thumb. “You can’t race on that.”

Volk Dean grew up visiting and racing at the salt flats, following in the footsteps of her father, Larry Volk.

In 1975, he earned a coveted Bonneville 200 MPH Club red hat after traveling 207.6 miles across the flats’ iconic salty surface. In 2003, when Volk Dean was just 23, she reached 236.3 miles per hour in a open cockpit roadster – and became the youngest inductee to the club at the time.

Now, she worries her own sons won’t get to experience the same thrill.

“I don’t know if there will be racing next year,” she said. “We’ve seen such a deterioration.”

Intrepid harvests potash from salty groundwater through a complex of canals and evaporation ponds, which concentrate minerals in the brine. Its salt flats facility covers about 141 square miles east of Wendover. Just over a third of the complex lies on lands owned by the Bureau of Land Management or state of Utah, and it paid around $400,000 in royalty payments to the state and federal government in 2023, SEC filings show.

Racing advocates want to see the BLM, which owns and manages the portion of the salt flats open to the public, resume a process called salt laydown to help rebuild the halite crust. The agency partnered with the Intrepid starting in 1997 to pump groundwater from the nearby Silver Mountains, mix it with the mine’s waste salt, and “laydown” the halite by flooding the flats.

For a while, it appeared to work. Satellite images show the salt flats started to grow again in the early aughts. But after 2009, they returned to their long-term pattern of decline.

The racers say it’s because Intrepid started mixing less halite with the water they pumped for the laydown process.

The racers tried in recent years to get a $50 million federal allocation to ramp up efforts and rebuild the flats. The state of Utah even offered to chip in another $5 million. But when the federal money never came, the state cut its funding to $1 million, and mostly earmarked it to facilitate more research.

“They’ve never changed anything,” Sullivan said. “They’ve just done study, study, study.”

But geologists like Radwin who have conducted some of the research on the salt flats say it was the groundwater pumping itself that caused the formation to melt away.

Drawing water from wells Intrepid taps for potash mining, along with the wells along the Silver Mountains used for salt laydown, altered the region’s hydrology. It caused the salty water that normally bubbles to the surface and replenishes the flats to instead flow away.

In its 2024 annual report filed with the SEC, Intrepid asserted it has donated 7 million tons of salt to the Bureau of Land Management since 2005 to help rebuild the salt flats race track. It noted it drilled another well in 2021 to increase the water available for its laydown efforts.

The mining company stopped salt laydown in 2024 and 2025, however.

Asked why Intrepid paused the process, a spokesperson for BLM noted the U. study that found laydown had shifted the flow of groundwater beneath the flats. She added that laydown stopped for “several reasons,” including because the process is only required if Intrepid mines leases on lands owned by BLM. She added that the agency is too understaffed to keep regular tabs on the company.

With the salt regeneration efforts at a standstill, a new company called Fast Track Lithium has floated another solution.

Its founder, Tom Currin, proposes partnering with Intrepid to reflood the salt flats again with a much thicker, heavier salt slurry. It would pump water from a deeper aquifer beneath the flats and saturate it with halite crystals.

The slurry would then move from Intrepid’s ponds through a pipeline with heavy-duty pumps, across the interstate and onto the flats. He would prioritize building up the speedway first.

Industries could also extract lithium from the salts — an important material used in electric vehicle batteries and other electronics — to pay for the process.

“So it would be a privately funded project,” he said, “not a government-funded project.”

Currin and Bonneville Salt Flats racing advocates took representatives from the Governor’s Office of Economic Opportunity and the Economic Development Corporation of Utah out to the flats during World of Speed last month to tout the proposal.

“If it works, we’re getting our salt flats back,” Sullivan told the group. “If I can convince you that this is worth saving, then he can get permission to start doing the lithium project.”

A spokesperson with the governor’s office declined to comment.

Privately, however, Sullivan expressed some doubts. How would they control where the salt slurry goes, for example, and ensure it stays put? They can’t build berms to keep the salt solution in place on the raceway, because cars wouldn’t have a safe area to emergency exit the track.

And ultimately, if Fast Track Lithium just wants to pump more water for its process, would it also backfire?

“I gotta support Tom,” Sullivan said, “but some of my concern is they’ve sucked the aquifer so low that the salt can’t naturally reproduce.”

Radwin, too, has his doubts as a geologist.

“The fundamental idea is a great improvement,” he said. “But ... I think they’re strongly underestimating the engineering challenges they’re going to face trying to transfer that slurry.”

Intrepid, which holds the water rights and salt stockpile needed to make the proposal work, has so far declined to cooperate, Currin confirmed.

Meanwhile, the mining company projects it has at least 25 years’ worth of potash left to extract at the salt flats, according to its filings with the SEC.

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