US Department of Energy (DOE) Office of Environmental Management (EM) crews have completed clean-up operations associated with the demolition of a major reactor at Oak Ridge National Laboratory (ORNL). Workers finished the teardown of the Low Intensity Test Reactor and disposition of rubble and debris from the facility last fall, achieving an EM priority that year. However, the reactor vessel remained on the building’s footprint until it could be shipped for final disposition offsite.

Employees loaded the 30-foot-long, 37,600-pound vessel onto a truck and shipped it to a facility in Clive, Utah, for final disposition. Known as Building 3005, the reactor was built in 1949 as a criticality testing facility that used highly enriched fuel with water as a coolant. It operated until 1968. Researchers used the reactor in numerous experiments through the years, and the core was often reconfigured to perform those experiments.

EM clean-up contractor UCOR characterised and sampled the reactor, employing multiple modelling software programs to develop the final characterisation enabling employees to identify how to safely transport and dispose of the reactor.

“Completion of decontamination and transporting the reactor vessel for disposition is a big accomplishment that presented technical difficulties and a unique safety focus to finalise the clean-up at the Building 3005 site,” said UCOR Project Manager Greg McGinnis.

Workers fill the pit where the Low Intensity Test Reactor vessel once stood. It was one of the final tasks associated with the clean-up project, clearing space to support two upcoming EM demolition projects. Workers backfilled the pit where the vessel was removed and completed repairs needed on the footprint.

“Completing these final tasks are crucial to our ongoing efforts at ORNL,” said Acting ORNL Portfolio Federal Project Director Jim Daffron. “Clearing and backfilling this area gives our employees a staging area to support safe and efficient demolition for our next two major projects.”

Workers are deactivating the Graphite Reactor support facilities and the Oak Ridge Research Reactor, which are adjacent to the footprints of the Low Intensity Test Reactor and Bulk Shielding Reactor. These projects are continuing EM’s mission to eliminate risks and enable future research missions and growth at the site.

Image: Aerial view of the footprint of the Low Intensity Test Reactor after demolition by the US Department of Energy Office of Environmental Management. Crews have since shipped the reactor vessel and backfilled the pit where the facility once stood (courtesy of US DOE Office of Environmental Management)