Utah has the last conventional uranium mill in the country. What does it do?

San Juan County • Trucks filled with thousands of pounds of rock roll up a paved road, the namesake twin buttes of Bears Ears National Monument visible in the distance on a clear day.

The dark gray rock is uranium ore headed to the White Mesa Mill in Utah’s rural San Juan County — the last remaining “conventional” uranium mill in the United States.

The country’s other 14 uranium mills solely process rock from the site where they’re located. This leaves White Mesa as the only American uranium mill still accepting ore and other radioactive materials from around the country and the world.

It was one of nearly two dozen conventional mills in the U.S. when it opened in 1980, just south of Blanding, and it’s now far past its projected 15-year lifespan. Demand for uranium fell — aside from some spikes — over the decades, and mill owner Energy Fuels pivoted to also processing leftover radioactive materials from other countries, rare earth elements and producing medical isotopes.

But with the growing global push for clean energy and recent international instability, demand has skyrocketed for the “yellowcake” that the mill creates. Uranium was worth less than a dollar per pound in September 2022, reached over $100 per pound in January and is valued at $80 per pound today, according to Business Insider.

Yellowcake undergoes more processing in other states to become powerful nuclear fuel — just a soda can’s worth could satisfy the average American’s energy needs for their lifetime.

The White Mesa Mill, which the Energy Fuels CEO said had been “hanging on by a thread, literally,” for years, now plans to be open for the foreseeable future.

Utah lawmakers celebrate the industry as an economic engine that supplies rural, high-paying jobs. But its surge is condemned by people who cite concerns about the environment, including the Ute Mountain Ute Tribe’s White Mesa community five miles to the south.

Here’s what the mill does, and why it’s controversial.

Where does uranium processed in Utah come from?

The mill currently accepts uranium ore trucked from two mines also owned by Energy Fuels: the La Sal Mines Complex near La Sal, Utah, and the Pinyon Plain Mine, located in the Kaibab National Forest near the south rim of the Grand Canyon in Arizona.

Energy Fuels expects to receive ore from mines reopening across the American Southwest as demand for uranium remains strong, said Curtis Moore, the company’s vice president of marketing and corporate development.

White Mesa has also received uranium-bearing material from Estonia and Japan, shipped across the ocean and then trucked to the facility.

Most of the uranium used by American nuclear reactors is imported. Over half of the uranium purchased by the U.S. in 2022 came from Canada and Kazakhstan, followed by sizable imports from Russia, Uzbekistan and Australia, according to the U.S. Energy Information Administration.

What happens at the White Mesa Mill?

After uranium ore and other materials arrive at the mill site, they’re organized by type into separate piles to await processing. During a recent tour, Logan Shumway, the mill’s manager, explained the next steps.

For ore, that starts with equipment that pushes it through a large grate set in the ground into machinery that crushes it to a fine sand, which allows it to be more easily treated with chemicals.

Within a hot, airy building, the crushed ore is then mixed with water from wells on the site. That mixture goes into giant vats containing sulfuric acid from the Kennecott Copper Mine near Salt Lake City, salt from the Great Salt Lake, kerosene and ammonia.

Working together, the chemicals leach pure uranium out of the ore, transforming it into a yellow dust.

The dust is baked in large, industrial ovens, and the final product is a dark, chunky powder composed of triuranium oxide, or U3O8 — commonly called “yellowcake,” though the industry prefers “uranium concentrate.”

From crushing ore to final product takes about seven days.

At that point, the first two steps of the nuclear fuel cycle — the mining and milling of uranium ore — have both taken place in Utah.

The mill packs the yellowcake into barrels. The vast majority of it — about 90%, according to Moore — goes to a uranium conversion facility in Metropolis, Ill., dubbed the “Hometown of Superman.”

At the Honeywell Uranium Hexafluoride Processing Facility, yellowcake is converted to uranium hexafluoride gas, which further concentrates the uranium. Honeywell is the only uranium conversion facility in the U.S., and one of the only conversion facilities located outside Russia and China.

Through additional processing in other facilities, the gas is eventually converted to a powder, which is compressed into small pellets that are fed into a nuclear reactor.

There, at last, the splitting of uranium atoms produces heat, which boils water into steam. That steam turns a turbine connected to a generator, producing electricity.

Shumway takes pride in the role he and his coworkers play in creating energy without generating carbon emissions. Shumway, who grew up in Blanding and has worked at the mill for 14 years, said he wishes more people understood what the White Mesa Mill actually does.

After destructive accidents at nuclear power plants at Pennsylvania’s Three Mile Island, Chernobyl and Fukushima, the U.S. “really stifled and shut down any expansion and growth and research about this field, so nuclear is really in its infancy still,” Shumway said.

“So, if you judge [nuclear energy] on that basis, it’s amazing,” he continued. “It should be so much more than it is in terms of the understanding and technology of it, and our utilization of it for power.”

Why has transporting uranium ore or materials to Utah been controversial?

In July, Energy Fuels sent two truckloads of uranium ore from the Pinyon Plain Mine north across the Navajo Nation to the White Mesa Mill. The tribe’s president said he wasn’t notified of the transport, and the conflict has led to a pause in trucking from the mill as Energy Fuels and the Navajo Nation discuss safety concerns.

The Navajo Nation has since strengthened its regulations for radioactive material transport.

“Because of the price of uranium, we know that there are several other proposed mines that are in development,” Stephen Etsitty, executive director of the Navajo Nation Environmental Protection Agency, said at a Navajo Nation Council meeting in August.

Utah industry leaders say that incentivizing American uranium production fortifies the U.S. against national security threats associated with relying on Russia and its allies for the material. That view was amplified nationally in May, when President Joe Biden signed a law banning Russian uranium imports.

But the U.S. is home to just 1% of the world’s uranium resources, according to 2021 data from the World Nuclear Association. That means arguments for ramping up domestic uranium production in the U.S. are “ridiculous,” contends Sharon Squassoni, a research professor at George Washington University’s Elliott School of International Affairs.

“There is no getting away from buying foreign,” she said.

Other supporters of nuclear power say that stringent regulations in the U.S., compared to other countries, for protecting the environment, employees and public health are another reason to bolster domestic uranium production.

But environmental organizations like the Grand Canyon Trust object that the mill’s processing of foreign radioactive material shifts the harm of radioactive waste from overseas to southeastern Utah.

Shumway disagrees. “People say we’re a waste disposal, that this is a dumping ground. No,” he said. “We’re taking a liability and turning it into something that’s actually good for people.”

Energy Fuels was incorporated in Canada but is headquartered outside of Denver, Colo., and primarily trades on the New York Stock Exchange.

What concerns do people have about White Mesa Mill’s processing?

Scott Clow, the Ute Mountain Ute tribe’s director of environmental programs, has been studying the White Mesa Mill’s impacts since 1996.

He said the tribe’s concerns start with how long uranium ore and other materials sit in piles outside the mill, exposed to the elements, before they’re processed. Some materials shouldn’t be exposed to the hot, southeastern Utah sun, Clow said, and wind can blow potentially radioactive dust off of them.

There is “no set length for how long ore can stay on the ore pad,” Moore said, but added that he believes concerns related to the piles are “unfounded.” The company uses a water truck to spray down piles to prevent blowing dust, for example, and limits their height. It stores some materials under a roof or in containers. And air and groundwater are monitored, the company adds.

”There is zero scientific evidence to suggest that any of the mill’s operations, including raw material storage, is causing any adverse health or environmental impacts,” Moore said.

But the tribe and others say they still question whether, or how much, the mill is contaminating air and water as materials go through the milling process, and as the sand that’s left over from the crushed and treated ore is again piled outside.

Uranium eventually decays to radium, which decays to release a radioactive and carcinogenic gas called radon. The tribe worries about vegetation, water and air being contaminated by radon gas and radioactivity from waste, Clow said, and is not convinced that monitoring by the company and the state catches all of the exposures.

Anferny Badback, who grew up and lives in White Mesa, told the Inter-American Commission on Human Rights in February that the mill has also affected his community spiritually. He said that his ancestors’ remains buried in the area were “desecrated” when the mill was built, and that he and his neighbors are wary of using spring water and vegetation for ceremonial purposes, fearing they are contaminated.

“We want the mill shut down and properly cleaned up,” Badback said in a recent statement, released ahead of the tribe’s Friday rally at Utah’s Capitol in Salt Lake City against the mill. “We want the mill and its contamination to be moved where it can’t hurt any living things.”

Who regulates White Mesa Mill and how do they do it?

The U.S. Nuclear Regulatory Commission regulates radioactive materials, including nuclear power plants and those used in medicine. But Utah has been an “agreement state” for decades, which means the NRC’s authority over the mill has been passed to the Utah Division of Waste Management and Radiation Control.

In that role, the division also oversees the requirements set out in a 2011 permit from the state Division of Air Quality, which limits what the mill can release from its smokestacks when it dries yellowcake and other emissions, including radioactive dust.

There are seven air monitoring stations on the mill site that collect data 24 hours a day, seven days a week, Shumway said. Air from inside the mill is pumped through the stations, which monitor for harmful particles and radiation.

The state Division of Waste Management and Radiation Control reviews air quality reports from the mill twice a year and periodically inspects the monitoring stations, a spokesperson said. The agency also monitors environmental radiation, conducting “multiple inspections per year focused exclusively on potential radiation exposure,” the spokesperson said.

“We know for a fact whether or not there is radiation in dust leaving the site or not,” Shumway said. “There are not any problems, and there never have been.”

The division spokesperson said “it would be difficult to definitively state that radiation has never left the site,” but added that the state does “not have evidence that radiological contamination has left the site.”

Clow said the tribe feels the state and the company have not fully addressed its concerns about their monitoring, such as testing for fugitive radioactive dust, which the tribe raised in 2011 objections to the mill’s license renewal.

Mill workers each wear dosimeters — small, plastic radiation detectors that can be pinned to a shirt, Shumway said. The company checks employees’ radiation exposure on a weekly and monthly basis, he said.

“We are, on average, less than airline pilots,” Shuwmay said about their exposure.

Personal dosimeters are sent to a lab and the test results are analyzed by health physicists from the Division of Waste Management and Radiation Control “to make sure that no employee is receiving more radiation than is safe and allowable,” the division spokesperson said.

Those results, as well as measurements of radiation across the mill site, reveal the “potential radiation exposure onsite as well as the actual radiation received by employees.”

What happens to the waste after the uranium has been leached out?

The chemical process that leeches uranium out of crushed ore produces sandy waste, called tailings, which both the Nuclear Regulatory Commission and the Environmental Protection Agency explain are radioactive.

The mill’s tailings are stored at the site in containment ponds. Newer ponds have triple-layered liners, which sit atop a layer of clay, to prevent tailings from getting into groundwater, Shumway said. Those ponds also have leak-detection systems.

Once a pond is filled with tailings, the company will ensure it’s dry and place an engineered cover — of about eight feet of dirt and gravel — over it.

“Once they’re sitting and covered there, I would go build my house right across the street,” Shumway said. “There’s no real reason that would be dangerous to anybody down the road if it’s done right.”

But the older ponds installed in the late 1970s and early 1980s, Clow said, don’t have those same protections. Moore said that those containment ponds are single-lined, with “with leak detection and dewatering systems that met best available technologies when they were built.”

A former mill worker, who worked for a previous owner on and off from 1997 to 2014, has said he saw old liners cracking.

But under Energy Fuels’ ownership, Moore said, “there is no indication that any of the cells at the mill are leaking.”

There are over 40 groundwater monitoring wells at the White Mesa Mill site, Shumway said, and samples from them are sent to an independent laboratory in Salt Lake City to be checked for contamination.

“Of course, you have to contaminate the aquifer in order to detect it,” Clow said.

The mill also sends soil and vegetation samples for analysis. And the waste management division visits the mill multiple times a year to monitor radiation. The agency also takes samples from seeps and springs along the edge of the mill site.

The division spokesperson said there are two known groundwater plumes at the mill site: a nitrate plume and a chloroform plume. These are concentrated areas of contaminants in groundwater.

“Evidence indicates that these plumes predate Utah becoming an Agreement State,” the spokesperson said, though the state division is responsible for monitoring and managing them.

“There is no evidence of radiological contamination of the groundwater, and the plumes are contained to the site,” the spokesperson said. The most recent report from the mill, she added, found that all radioactive particulates at the sampling locations were “well below” the limits permitted by state law.

The Ute Mountain Ute Tribe has partnered with the EPA to install groundwater monitoring wells between the mill and the tribe’s White Mesa community. The tribe has not detected any contamination of the springs that seep out from the mill site’s perimeter since the early 2000s, Clow said.

When the White Mesa Mill eventually closes, the mill will remove surface soil from the site and place it in the containment ponds as part of its decommissioning plan, according to the Division of Waste Management and Radiation Control.

The mill’s plan for decommissioning the facility will cost $25 million, a figure reviewed and periodically updated by the state. The U.S. Department of Energy’s Office of Legacy Management will then take over long-term monitoring of the site.

Why is nuclear power seeing a resurgence?

The Three Mile Island plant, the site of the worst nuclear accident in U.S. history, plans to reopen in Pennsylvania in 2028. The Palisades Power Plant in Covert, Michigan, hopes to beat it and become the first nuclear reactor to restart operations.

Rapid change in the global climate has driven a push for nuclear and other clean energy development, like solar and wind. Coal, oil and natural gas emit greenhouse gases that warm the planet, and climate scientists say that pivoting away from those fuels is essential as demand for energy is only growing worldwide.

The many concerns about nuclear power, however, include the hazardous waste that remains. “Spent” uranium fuel is highly radioactive; brief direct exposure can be deadly; and “there is no facility available for permanent disposal of high-level waste,” according to the Nuclear Regulatory Commission.

Nuclear power plants also are complex and costly to build, leading to long construction timelines. “Nuclear energy is a waste of time and money if you’re seeking to mitigate the worst impacts of climate change as quickly as we can,” Squassoni argues.

Still, many scientists herald nuclear power as a major player in slowing global warming, and warn that “continued opposition to nuclear power threatens humanity’s ability to avoid dangerous climate change.”

Clow said he agrees that clean nuclear energy could be useful in addressing the climate crisis.

“But a lot of people that support nuclear power don’t have any idea of the profound impact that it’s had on this region of the country,” he said, nodding to irradiated groundwater and abandoned mines on the Navajo Nation. ”There’s all kinds of these uranium mine and mill sites around, and they’ve profoundly impacted people and will continue to profoundly impact people.”

During the past two decades that White Mesa produced little yellowcake, the tribe worried about the environmental impacts of past uranium processing, he said. Now, the company says it anticipates “a large-scale uranium processing campaign” at the mill into 2026.

“All of the environmental pollutants that we’re concerned about during a mothball period,” Clow said, “are going to be amplified in the near future.”