How much Manhattan Project radioactive waste is left in Oak Ridge? | Know Your Knox

On the wall of Jay Mullis' office in Oak Ridge is a chart detailing billions in federal funding needed over the next 25 years to clean up radioactive waste left over from World War II and the Cold War.

Mullis manages the Oak Ridge Office of Environmental Management, whose work includes shipping highly radioactive materials out of the state, monitoring mercury contamination in the Upper East Fork Poplar Creek and clearing contaminated buildings across the region for future clean energy and national security missions.

It is part of the largest cleanup effort in the world, led by the Department of Energy, whose 107 sites across the U.S. take up about the same space as Delaware and Rhode Island combined. The department has finished cleanup at 92 sites, and Oak Ridge is one of the 15 remaining, along with fellow Manhattan Project sites in Hanford, Washington and Los Alamos, New Mexico.

Mullis' detailed wall chart extends all the way to 2047, the year he expects his office could finish cleanup of hazardous facilities at Oak Ridge National Laboratory. It won't be until at least three years later, in 2050, that it finishes cleaning up Y-12 National Security Complex, where unused buildings that once enriched uranium for the bomb dropped on Hiroshima are literally falling apart.

It is generational work, he said. It is also dangerous and expensive work that must be conducted very close to where thousands of scientists and engineers come to work every day.

Oak Ridge cleanup is popular with lawmakers

Cleanup of Oak Ridge's nuclear past relies entirely on appropriations from Congress, which much be secured freshly each year. It hasn't been difficult for the office to make its case to lawmakers, especially since it cleared the massive former K-25 site, once home to the world's largest building, four years ahead of schedule and $80 million below budget.

To date, Oak Ridge cleanup has cost around $14.6 billion, and will likely take about that much more to finish, a spokesperson from the Oak Ridge Office of Environmental Management told Knox News.

Mullis said funding for his office has risen sharply since around 2015, a sign of lawmakers' confidence in its ability to return on the investment.

“When have you ever heard of a government project running ahead of schedule and under cost?” Mullis said. “If you’ve got extra money, this is the place to send it because we can get stuff done.”

The Biden administration's budget request for the next fiscal year included $635 million for Oak Ridge cleanup. In total, nuclear site cleanup across the U.S. is expected to receive about $8.3 billion.

Through cleanup of the K-25 site, now known as the East Tennessee Technology Park, the Oak Ridge Office of Environmental Management gave land seized from local owners by the federal government for the Manhattan Project back to the city, where the acreage will now be used by private companies contributing to the local tax base.

Giving land back to Oak Ridge and protecting the region's environment are two missions that make the project attractive to lawmakers.

“This is something that has tremendous bipartisan, bicameral and administration support,” said U.S. Rep. Chuck Fleischmann, R-Chattanooga, in an interview for a Department of Energy web series in October. “We are cleaning up legacy sites, sites that are dirty, in communities all over the United States.”

As chair of the U.S. House subcommittee that appropriates money for water and energy projects, Fleischmann has advocated for tax dollars going to environmental cleanup.

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How nuclear waste in Oak Ridge gets cleaned up

Dozens of buildings across the Oak Ridge Reservation, the 30,000-acre tract of land owned by the Department of Energy, once housed nuclear reactors and radioactive material that contributed to scientific research and weapons development.

As their missions came to an end following World War II and the Cold War, these buildings were mostly left to nature since it would have cost millions to maintain them, Mullis said. At their core are hot cells, incredibly heavy metal containers that protected workers from radioactive nuclear fuels once stored in reactors.

In order to clean the buildings and safely demolish them, workers must first deactivate them, a process that accounts for 70% to 80% of total project costs for each facility, Mullis said.

The Oak Ridge Office of Environmental Management has 84 federal employees, including engineers and geologists, and nearly all of its deactivation and demolition work is carried out by contractors. United Cleanup Oak Ridge, known as UCOR, is its lead contractor with 2,000 employees. The office's current 10-year contract with UCOR is valued at $8.3 billion.

The highest-level radioactive waste from Oak Ridge is shipped to places like the Nevada National Security Site, a Department of Energy facility in the middle of the desert, Mullis said. Though it represents less than 10% of the volume of waste from Oak Ridge legacy sites, this material carries over 90% of its radioactivity.

The bulk of low-level radioactive waste is buried in on-site landfills in Oak Ridge.

If all waste were shipped out of state, the Oak Ridge Office of Environmental Management would incur an added cost of between $800 million and $1.4 billion, Mullis said.

The final two steps in the cleanup process are demolition and soil remediation. After demolition finished at the former K-25 site, a smaller crew began cleaning the soil and monitoring groundwater beneath the plant's footprint. It's work that is ongoing.

Demolition crews were then able to move their focus to ORNL and Y-12, where legacy buildings are being deactivated and torn down at an accelerating pace. In the past two years alone, crews have demolished two research reactors in the central campus of ORNL that were built following World War II. UCOR is preparing another research reactor nearby for demolition.

At Y-12, crews are preparing to demolish a Manhattan Project-era building this spring and expect to finish a large mercury treatment facility in 2025.

What would happen if Oak Ridge cleanup stopped?

Oak Ridge is the kind of place where it's common to find "material you didn't expect," Mullis said.

For instance, a contractor sent out to Y-12 to examine a legacy site touched a pipe so rusty it broke apart and mercury began dribbling out. The element was vital to early weapons development. Now, it "weeps" out of the walls of several Y-12 buildings when the weather gets hot, Mullis said.

Sometimes the surprises are even bigger. When crews prepared the Biology Complex at Y-12 for demolition, they found rooms they didn't know existed behind boards. In these hidden rooms, crews found jars of mice in formaldehyde and long-forgotten logbooks.

The sprawling facility, nicknamed the "Mouse House," pioneered research into the effect of radiation on genetics. It had been left vacant for decades and trees were growing up through its roof.

Crews completed demolition of the complex in 2021, clearing the 18-acre footprint for a new Lithium Processing Facility that will move Y-12's operations of the element away from a deteriorating Manhattan Project building.

What if all of this cleanup work suddenly stopped? For one thing, hazardous materials would find their way into nearby creeks and rivers, Mullis said. For another, ORNL and Y-12 would be unable to pull off their ambitious modernization plans.

Decades ago, safety precautions and regulations were not as rigorous as they are today. Buildings were thrown up quickly in the rush to develop nuclear weapons and research faster than the U.S.'s rivals.

Though aspects of that mission survive today in Oak Ridge, many of those facilities are overdue for a makeover. In their place, the Department of Energy will build new emblems of U.S. nuclear strength. They'll just take a lot longer to build.

“I’ve always been a big history buff,” Mullis said. “It’s pretty cool to me to be here and be able see the history of the Manhattan Project, because this is, in many ways, where it started.”

Know Your Knox answers your burning questions about life in Knoxville. Want your question answered? Email knowyourknox@knoxnews.com.

Daniel Dassow is a growth and development reporter focused on technology and energy. Phone 423-637-0878. Email daniel.dassow@knoxnews.com.

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This article originally appeared on Knoxville News Sentinel: Manhattan Project radioactive waste in Oak Ridge cleanup continues