Steps the Oak Ridge Office of Environmental Management and United Cleanup Oak Ridge are taking to address the Alpha-4 facility at the Y-12 National Security Complex. Image by United Cleanup of Oak Ridge

OAK RIDGE, TN - The Oak Ridge Office of Environmental Management and cleanup contractor United Cleanup Oak Ridge (UCOR) are making significant headway preparing one of the most challenging facilities at the Y-12 National Security Complex for demolition.

Alpha-4, a 510,000-square-foot structure covering 13 acres of land, enriched uranium during the Manhattan Project and processed lithium during the Cold War. Past operations inside the facility led to heavy mercury contamination.

"Preparing a facility for demolition is always the lengthiest part of the process,” said Alpha-4 Federal Project Director Morgan Carden. "It takes time to remove the hazards from inside the facility so crews can take it down safely and efficiently. At Alpha-4, our crews have much more to account for and it’s at a much larger scale than recent projects.”

Teams have already completed placing the facility in "cold and dark" status — meaning they disconnected all utilities from the building.

Now, the teams are in the sanitization stage, which involves removing classified equipment to pave the way for other crews to enter and begin full deactivation.

They’re also addressing elemental mercury in the facility. The presence of mercury poses many challenges. Experts estimate nearly 450,000 pounds of the element to be in the equipment, facility and surrounding area. Its retrieval will continue to be a focus for project teams.

Teams have sorted and segmented 447 legacy containers from the Alpha-4 facility for transport and disposal. Image by United Cleanup of Oak Ridge

Crews have sorted and segmented 447 legacy containers inside the building for transport and disposal ahead of schedule.

After sanitization concludes in 2028, crews will begin characterization, waste removal, venting and purging process lines, and full scale deactivation.

Although Alpha-4’s cleanup is set to be a lengthy process, team members have identified solutions that have accelerated the timeline by nearly two years and saved $16.3 million.

Crews package and remove classified materials from the Alpha-4 facility as part of the sanitation stage. Image by United Cleanup of Oak Ridge

Crews began using a new drum crusher that speeds work to reduce the size of legacy drums for disposal, avoids risk associated with performing the task manually, and yields substantial cost savings. An effort that reduced the number of items needing to be declassified has also shortened the sanitation stage.

"Thoughtful planning and a proactive questioning attitude are paramount in a project of this scale and complexity," said Wayne Sproles, UCOR’s Y-12 deactivation and demolition manager. "We are constantly evaluating our approaches to ensure the safest and most cost-effective methods."