The fuel is from the Sodium Reactor Experiment launched in California in the 1950s to determine whether nuclear power could provide household electricity.
The sodium-cooled reactor made history in 1957 by powering homes in Moorpark, and two years later, after an accidental coolant blockage, also became the first U.S. reactor to experience a meltdown.
Today, its leftover fuel is among more than 15,000 used assemblies stored at SRS for processing at H Canyon, which houses the nation’s sole remaining facility where certain types of plutonium, highly enriched uranium and aluminum-clad spent fuels can be processed for disposal.
The fuel is the first batch to be processed at H Canyon since the U.S. Department of Energy announced plans to scale back operations and place the facility in “standby mode” about 18 months ago.
Mike Swain, H Area’s environmental management operations director, said processing began in August after a series of exercises to make sure the facility and its personnel were ready to resume operations.
The degraded condition of the sodium reactor material led to its selection for processing, Swain said.
“It is currently the only allowable fuel we can process through the canyon,” he said. “We don’t have a record of decision to process other fuels.”
The used thorium uranium fuel had been stored at the site’s L Area and is composed of small pieces, or “slugs,” rather than typical fuel rod configurations, L Area facility manager Rick Reichel said.
The Sodium Reactor Experiment material was singled out last year by a federal oversight panel as needing urgent attention.
The Defense Nuclear Facilities Safety Board, in a 2011 report, warned that at least three of the 36 cans of material had ruptured from corrosion; and that uranium fuel in one can was so corroded that it left 36 kilos of oxide sludge at the bottom.
The processing involves transforming the used fuel into a semiliquid waste that will be sent to the site’s “tank farm” for storage until it is mixed with glass and “vitrified” and permanently sealed in steel canisters.
Swain said the project should be completed in late 2013.