Oak Ridge crews are deactivating Beta-4, as similar preparations for demolition draw to a close at another former Manhattan Project-era uranium enrichment facility, Beta-1, at the Y-12 National Security Complex. April 21, 2026
Office of Environmental Management
April 21, 2026
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Constructed in 1945, the Beta-4 facility takes up 360,000 square feet of space at the Y-12 National Security Complex.
OAK RIDGE, Tenn. — Oak Ridge crews are deactivating Beta-4, which spans the equivalent of nearly seven football fields, as similar preparations for demolition draw to a close at another former Manhattan Project-era uranium enrichment facility, Beta-1, at the Y-12 National Security Complex.
This marks a significant step forward in the Oak Ridge Office of Environmental Management’s (OREM) effort to remove legacy hazards, enable modernization and open space for important national security missions at Y-12.
The National Nuclear Security Administration (NNSA) enabled this latest milestone by transferring operational responsibility of the 360,000-square-foot Beta-4 to OREM for the characterization, deactivation and demolition work.
Following demolition, the footprint will be returned to NNSA to support critical mission needs.
Before-and-after views of Beta-4’s footprint. Workers installed temporary structures and prep areas to support cleanup crews working on the facility’s deactivation.
Some United Cleanup Oak Ridge (UCOR) crews are performing characterization work at Beta-4 — sampling equipment and materials to support safe waste removal, packaging and disposal — while others are busy with “cold and dark” activities — isolating utilities, removing hazards and verifying systems are safely shut down.
The crews are already a step ahead after completing a major infrastructure project laying the groundwork for the current phase of cleanup at Beta-4. They built several temporary structures to position craft professionals and support teams closer to the facility, reducing travel time across the site for equipment and resources. This infrastructure will also support other major cleanup projects nearby.
“This infrastructure is the work before the work that will allow our teams to be closer to cleanup,” said Tanner Holsomback, UCOR project manager for Special Partnership Programs. “By reducing time spent away from the jobsite, we’re increasing productivity and setting the stage for successful deactivation and demolition at Beta-4.”
This next phase of cleanup highlights the broader momentum happening across Y-12 as crews reduce risk and help transform the site for new uses.
-Contributor: Ryan Getsi
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