The National Nuclear Security Administration (NNSA) in December removed some surplus, weapon-usable plutonium from the Savannah River Site in South Carolina, the agency said Friday. 

The agency did not say how much of the material it removed from the site near Aiken, S.C. The NNSA has said the glove boxes and facilities needed to blend the plutonium with concrete-like grout at Savannah River will not be fully operational until 2028 or so.

“This shipment marks a milestone as the first shipment to include defense TRU [transuanic waste] material from NNSA’s Surplus Plutonium Disposition Program,” the NNSA wrote in

a press release. “After plutonium is downblended at SRS [Savannah River Site], it becomes TRU material by definition and can be permanently disposed at” the Waste Isolation Pilot Plant in New Mexico.

Under the NNSA Surplus Plutonium Disposition Program, the replacement for the Savannah River Site’s canceled Mixed Oxide Fuel Fabrication Facility, the government planned to dispose of 34 metric tons of plutonium by processing it at the Los Alamos National Laboratory in northern New Mexico, grouting it at Savannah River and burying it at the Waste Isolation Pilot Plant near Carlsbad, N.M.

In 2020, the federal government and the state of South Carolina settled a long-running lawsuit over the NNSA’s failure to begin removing this weapon-usable plutonium by a legal deadline of 2016. 

Under the settlement, the federal government paid South Carolina $600 million from the Department of Justice’s Judgement Fund — not the Department of Energy’s budget — and South Carolina agreed to give the agency until 2037 to remove 9.5 tons of surplus plutonium from the state by 2037.

If the NNSA misses that deadline, the government will have to pay South Carolina $1.5 billion more, according to the terms of the settlement.