OREM Prepares for Removal of Final Hot Cell at Former Lab

Source: EM Update | Vol. 13, Issue 40; Contributor: Carol Hendrycks | October 12, 2021

A crew moves a high-tech imaging camera into the final remaining hot cell at the former Radioisotope Development Laboratory at Oak Ridge National Laboratory. The detector overlays a radiation-intensity color-map on a picture of the environment to show nuclides and their locations.

Crews are getting ready to deactivate the final hot cell of the former Radioisotope Development Laboratory at Oak Ridge National Laboratory (ORNL) in advance of demolishing the structure.

“Removing the remnants of the former Radioisotope Isotope Laboratory has been a priority for several years,” ORNL Portfolio Federal Project Director Nathan Felosi said.

“Its removal next year will eliminate a high-risk structure in the heart of ORNL and clears space for continuing science missions at the site.”

UCOR, EM’s cleanup contractor at Oak Ridge, is characterizing the final hot cell, a process that identifies radiological and hazardous contamination within, allowing workers to plan its deactivation. This work is being conducted under a six-story protective structure erected last year to ensure nearby facilities and ongoing research missions at ORNL aren’t impacted by the cleanup.

Workers are using an innovative technology, a specialized radiation detector, to help characterize the cell. The detector overlays a radiation-intensity color-map on a picture of the environment and identifies gamma-ray emitting nuclides and their locations.

Steps taken to enable characterization work include removing a wooden membrane covering the roof, installing and testing fire suppression and detection systems, placing gravel over the exposed floor to reduce dust inside the protective cover, and installing a negative air machine to provide localized ventilation during characterization and future deactivation.

“Preparing to demolish contaminated structures requires a lot of preparation to safely complete the demolition,” Oak Ridge Reservation Environmental Cleanup Program Manager Dan Macias said. “The removal of this hot cell is another significant step forward in ongoing cleanup activities at ORNL.”

The cell set to be deactivated and demolished will join five other cells and an outer structure previously demolished. The outer structure and four of the cells were demolished in prior years, and the fifth cell was demolished earlier this year.

The cells were heavily shielded concrete rooms that provided researchers protection from radioactive material as they conducted research. The laboratory was built in 1945 to support isotope separation and packaging and was later used to examine irradiated reactor fuel experiments and components.