More than 16 million tons of radioactive mill waste removed from project near the Colorado River

The decades-long federal cleanup of radioactive uranium mill waste north of Moab has surpassed the project’s original 16-million-ton estimate for the main tailings pile, marking a major milestone in one of the nation’s largest environmental remediation efforts.

About 16.2 million tons of tailings and mill debris had been shipped by the end of December to an engineered disposal cell near Crescent Junction, about 42 miles northwest of Moab, according to a Jan. 27 presentation to the Moab Tailings Project Steering Committee.

Moab Mayor Joette Langianese, who has involved with the project since the early 2000s, called the progress significant.

“There was a time when we didn’t know if we’d be alive to see this finished … so reaching this stage is a really big deal,” she said.

The total exceeds the commonly cited 16-million-ton estimate, though roughly another 1 million tons of sub-pile and off-pile material remains. Groundwater treatment, soil verification and long-term oversight continue, with the Department of Energy aiming to complete cleanup in 2029.

As the project approaches that milestone, related legislation in Washington is also advancing. The Moab Uranium Mill Tailings Remedial Action (UMTRA) Project Transition Act moved unanimously out of the U.S. Senate Energy and Natural Resources Committee on Feb. 4. The bipartisan bill, led by Sen. John Curtis and Rep. Mike Kennedy, would authorize the U.S. Department of Energy to transfer the former Atlas mill site to Grand County once remediation is deemed complete and safe for reuse, with any necessary land-use restrictions in place.

Curtis said the bill also has support from other members of Utah’s congressional delegation. Grand County and the City of Moab have also submitted formal letters backing it.

“The Moab UMTRA site has been the focus of one of the most significant environmental cleanups in the country, and as that work nears completion, it’s essential that we plan responsibly for the future,” Curtis said. “This legislation ensures the land can be safely transferred and that Grand County — not Washington — is empowered to decide what comes next.”

The UMTRA project was launched to address a legacy left by nearly three decades of uranium milling at the former Atlas Minerals site along the Colorado River north of Moab. From the mid-1950s until it ceased operations in 1984, the mill processed uranium ore and left behind an estimated 16 million tons of radioactive tailings in an unlined impoundment near the river, according to the Department of Energy. The former mill property covers roughly 480 acres.

The mill operated during the Cold War uranium boom before later supplying commercial nuclear markets. Atlas Minerals later declared bankruptcy, and the Department of Energy assumed responsibility for the site in 2001, according to The Salt Lake Tribune.

The location and composition of the waste raised concerns about contaminants — including ammonia and uranium — entering groundwater and migrating toward the Colorado River. Cleanup planning continued through the early 2000s under the authority of the Uranium Mill Tailings Radiation Control Act, but large-scale physical removal of tailings by rail to the Crescent Junction disposal cell did not begin until 2009. Material shipped there is placed in an engineered repository designed to be capped with layers of soil and rock.

The Department of Energy is operating with an authorized $64 million fiscal year 2026 budget to support ongoing cleanup and closure work. Federal appropriations in recent years have generally ranged from about $60 million to $75 million annually, according to the department’s website.

Work continues beyond the pile

While the tailings mound has largely disappeared, rail shipments are continuing at about four trains per week to move remaining sub-pile and off-pile material not included in the original 16-million-ton estimate, according to the Jan. 27 steering committee presentation.

Groundwater remediation remains one of the project’s longest-running components. The Department of Energy began an interim action system at the Moab site in 2003 to address elevated ammonia and uranium concentrations in groundwater discharging toward the Colorado River, according to the steering committee presentation. The system extracts contaminated groundwater and injects diverted river water to dilute ammonia discharge.

More than 7.4 million gallons of water were injected in 2025 alone, according to the presentation. Over the life of the project, extraction efforts have prevented an estimated 1,002,109 pounds of ammonia and 5,816 pounds of uranium from reaching the river.

The project has entered a verification phase intended to confirm cleanup standards are being met across the site. Jessica Thacker, Grand County’s UMTRA liaison and technical inspector, said ongoing monitoring and treatment will remain critical as the project moves toward closure.

“From an environmental perspective, the amount of effort in operations and scientific consideration is very mindful of the community,” Thacker said. “The DOE and subcontractors have made progressive efforts to ensure that all avenues of environmental remediation are being considered.”

The cleanup has operated under a Grand County conditional use permit, which requires the Department of Energy to coordinate with local land-use planning and meet site-specific conditions, including revegetation and restoration standards as work progresses. Langianese said the permit requirements are intended to help ensure the area is returned as closely as possible to its natural state once major earth-moving ends.

Even after bulk removal ends, long-term oversight is expected to continue under the Department of Energy’s Office of Legacy Management, which is responsible for ongoing groundwater monitoring and land-use compliance at former cleanup sites nationwide.

Looking ahead to potential future use of land

For those who have followed the project for decades, surpassing the original pile estimate signals a shift from bulk removal to longer-term planning about what the site could become once federal cleanup obligations are met and if the property is transferred locally.

Grand County Commissioner Mary McGann, who chairs the Moab Tailings Project Steering Committee, said discussions are increasingly focused on what infrastructure the county may want to keep if the property is conveyed, including modular buildings, utilities, trail connections and natural features such as an existing pond. She said the committee has been asked to begin identifying preferences by June, though final decisions remain years away and will depend on funding and federal approvals.

Long-range ideas for the property have been shaped through a recurring public-planning effort led by the Site Futures Committee and updated roughly every five years.

The most recent update in 2023 showed strong support for resident-focused amenities such as trails, river access, event space and transit facilities, while generating less enthusiasm for federal offices or intensive commercial development, according to steering committee materials.

Langianese said the planning effort began years ago in part to demonstrate to federal decision-makers that the community had a vision for the land beyond remediation. As cleanup nears completion, she said those conversations are becoming more practical — centered on what infrastructure is realistic to keep, what projects are financially feasible and how improvements could be phased in over time.

“The exciting part is, what do we want our gateway to the town to look like now?” Langianese said, describing the shift from a landscape once dominated by the tailings mound to one where drivers descending Moab Canyon can again see the river and the city.

Both Langianese and McGann said future land-use planning will again involve public input, likely either following a formal transfer of the property or during the next five-year planning update.

Langianese said a joint meeting between the Grand County Commission and Moab City Council is likely in April to discuss, among other issues, coordination on the site’s future, with more details expected as plans are finalized. She also noted a community celebration is expected in April to mark completion of bulk tailings removal, with additional information to be announced.

Both emphasized that any redevelopment would likely occur in phases and depend heavily on available funding. Community leaders have looked to Grand Junction, Colorado’s Los Colonias Park — a former uranium mill site remediated into parkland and event space — as one example of what a cleaned-up site can become, though they stressed Moab’s outcome will ultimately reflect local priorities and financial realities.

“Before it was … more conceptual, like this is our dream for this area,” Langianese said. “Now we get to see how we can reasonably make it a reality.”

This story was first published by The Times-Independent.