Source: EM Update | Vol. 10, Issue 14; Contributors: Wayne McKinney and Ben Williams | April 10, 2018

Crews conduct a process known as “fogging” to blow a fixative material into contaminated hot cells and laboratories to encapsulate and immobilize radioactive contamination.

DOE’s Oak Ridge Office of EM (OREM) and its cleanup contractor URS|CH2M Oak Ridge (UCOR) have completed one of the final steps to ensure a highly contaminated building at the Oak Ridge National Laboratory (ORNL) remains safe.

Building 3028, known as the Radioisotope Production Lab, contains seven inactive hot cells and former laboratories used for isotope and target fabrication production from 1950 until 1985. The facility is located in ORNL’s central campus near modern infrastructure housing thousands of researchers and staff.

The hot cells were emptied years ago, but the internal surfaces were still highly contaminated. To reduce the hazards, the team recently applied a fixative to encapsulate and immobilize the radioactive contamination. This process, known as “fogging,” is used to blow a fixative material into the hot cells and laboratories to plate the interior surfaces.

Workers conduct “fogging” to plate interior surfaces.

This project is part of DOE’s Excess Contaminated Facilities Initiative. Using special congressional funding, OREM is enhancing safety at ORNL and the Y-12 National Security Complex by removing risks and stabilizing buildings as they await eventual demolition.

“Through the Excess Contaminated Facilities Initiative, we are continuing to execute meaningful risk reduction projects across ORNL,” said Bill McMillan, ORNL portfolio federal project director. “This project is another example of how our cleanup program is working to keep employees safe and enable DOE’s important ongoing missions.”

Isotope and target fabrication production took place in Building 3028, which operated from 1950 until 1985. Through the Oak Ridge Office of EM’s work, it is now in safe standby mode.

The team completed the tasks inside Building 3028 safely and without any issues. They applied four coats of the fixative. After the material dried, workers took samples to determine the effectiveness of fogging, and the results demonstrated success in controlling residual radioactivity contained within the hot cells.

The only non-industrial hazard identified in Building 3028 is the residual surface radioactive contamination, which was addressed by fogging. The four-story structure is in safe standby mode, and the only remaining operations inside the facility are related to OREM’s surveillance and maintenance activities.