Oak Ridge’s Transuranic Waste Processing Center gets upgrades

The Department of Energy's Office of Environmental Management has announced that part of the Transuranic Waste Processing Center (TWPC) at the Oak Ridge Reservation cleanup site has been remodeled and updated with new equipment. The upgrades will allow that part of the facility to process forms of transuranic (TRU) waste different from what it had processed in the past in order to support efficient site cleanup.

The TWPC comprises four areas: a 5-line contact-handled glovebox, a 1,000-square-foot hot cell facility, a large box breakdown area, and a cask processing enclosure (CPE). The CPE is the area that has been updated.

History of the TWPC and the CPE: For decades starting in the 1940s, Oak Ridge was the site of nuclear research and operations related to defense and national security missions. This work produced TRU waste-radioactive material with an atomic weight greater than that of uranium, such as plutonium-that was stored for years on site.

Today the United States has one permanent disposal facility authorized to received defense-related TRU waste from Oak Ridge and other DOE sites: the Waste Isolation Pilot Plant in Carlsbad, N.M. However, before TRU material can be shipped to WIPP, it must be treated and packaged for disposal.

DOE-EM constructed the TWPC in 2003 to process Oak Ridge's legacy TRU waste, including lower-radioactivity contact-handled waste, which can be manually sorted, and higher-radioactivity remote-handled waste, which is sorted using manipulation devices that employees control. The TWPC is capable of processing both solid and liquid waste streams.

The CPE began operating in 2012. Before it came into use, crews had been using the TWPC's hot cell facility to process waste initially characterized as remote-handled waste that had been buried in concrete casks. However, removing waste later found to be contact-handled waste, along with variations in dose rates from items in the casks and other factors such as groundwater penetration, resulted in the need to frequently repair the hot cell's fragile equipment, which created delays. The CPE was constructed in a way that allowed for more efficient sorting and packaging of waste.

After processing the waste from the buried concrete casks was completed, a soil mixer was added to the enclosure between 2018 and 2019. The CPE then was repurposed to treat contaminated soil from the remediation of an area of Oak Ridge where a legacy storage tank had been buried. That work has since been completed at the CPE as well.

New purpose: The latest modifications to the CPE, which began in February, are designed to convert the space into an area where crews can process large waste boxes from the demolition work in progress at two areas of the Oak Ridge Reservation: Oak Ridge National Laboratory and the Y-12 National Security Complex. (Cleanup of the site's third area, the East Tennessee Technology Park, is almost complete as of this writing.)

To achieve this, the Oak Ridge Office of Environmental Management and contractor United Cleanup Oak Ridge removed soil excavation and processing equipment as well as outdated controls from the CPE. They then reworked the ventilation system, installed new cameras and monitoring software, and fitted the CPE with a drum crusher.

"We have a relatively small footprint, so repurposing nonfunctional space and providing more tools to our skilled workforce is essential to accelerating legacy waste cleanup on the Oak Ridge Reservation," said Adam Fraser, operations manager for the TWPC.

The updates build on an achievement that OREM and UCOR celebrated earlier this year: In June, the TWPC reached its target for its first year of processing legacy oxide waste four months ahead of schedule.