PHOENIX — The Savannah River Site could send as many as 40 shipments of diluted surplus plutonium to the Waste Isolation Pilot Plant in 2024, a manager at the Savannah River Site said here.

Or maybe half that many, Lee Sims, K Area Facility Manager at Savannah River for the site’s Fluor-led prime contractor, Savannah River Nuclear Solutions.

“Between 20 and 40 shipments a year is kind of where we’re headed over the next year,” Sims said Tuesday in a technical session at the annual Waste Management Symposia.

In the 2023 calendar year, the Waste Isolation Pilot Plant (WIPP) in New Mexico received 18 shipments of down-blended plutonium from Savannah River’s dilute and dispose program, according to WIPP’s public website. That accounted for most of the site’s 28 shipments of contact handled transuranic waste to the mine that year.

Eventually, Sims said, the dilute and dispose program wants to be able to send four shipments a week, or 208 shipments a year, to WIPP, where the material will be permanently buried as part of a National Nuclear Security Administration (NNSA) program to purge surplus plutonium, including 34-metric ton tranche, from the U.S. stockpile.

Right now, the dilute and dispose program has only a single glovebox at Savannah River Site’s K-Area to mix plutonium oxide with a concrete-like material once known as stardust. The White House, in its 2025 budget request, asked for $40 million in nonproliferation construction funds to help build a second glovebox. 

That would be a drop from the $77M the construction account got in the 2024 appropriations bill signed late last week, but NNSA says it will have unspent appropriations to spend on the project next year because of delays completing its design this year. 

Eventually, the NNSA wants to operate three dilute-and-dispose gloveboxes at K-Site.

Meanwhile, the agency has short-term hurdles to deal with in the dilute and dispose program, which besides Savannah River relies on the Advanced Recovery and Integrated Extraction System at the Los Alamos National Laboratory’s PF-4 Plutonium Facility. Los Alamos converts plutonium metal into plutonium oxide for Savannah River to pack up for WIPP.

But in the 2024 National Defense Authorization Act that became law in December, Congress forbade the NNSA from expanding Los Alamos’ Advanced Recovery and Integrated Extraction System until the agency certifies that it can produce 30 pits a year in PF-4, which hosts both missions.

Pits are the fissile cores of nuclear weapon first stages..

Some of the surplus plutonium that will pass through K-Area on its way to WIPP is in pit form, but NNSA will not begin treating that material until some time next decade after deciding that the agency could not fit a new Pit Disassembly Facility at Savannah River into its busy construction queue. The 2025 budget request affirms that plan.

Any delay in removing plutonium from South Carolina could get the NNSA sued, under the terms of a settlement the Department of Energy reached with the state in 2020.

According to a slide Sims briefed here Tuesday, K-Area’s plutonium inventory stood at just over 11.6 metric tons in 2019. That included 5.4 metric tons of weapons grade plutonium oxide, 2.5 metric tons of weapons grade plutonium metal, 2.5 metric tons of fuel grade plutonium oxide and 1.2 metric tons of fuel grade plutonium metal.

In 2024, Sims said, the dilute and dispose program might process 250 kilograms of plutonium.

“We’ve got a ways to go,” Sims said Tuesday.