Addressing the elephant in the desert, an official with the National Nuclear Security Administration (NNSA) on Wednesday warned that ongoing nuclear-weapon maintenance will require a transuranic waste disposal site that is open beyond 2050: the current, best-case availability for the Waste Isolation Pilot Plant in New Mexico.
“From an NNSA perspective, with an enduring mission, we are going to continue to have a need to dispose of transuranic waste past 2050,” James McConnell, the National Nuclear Security Administration’s associate administrator for safety, infrastructure, and operations, said Wednesday at the ExchangeMonitor’s virtual RadWaste Summit.
“Far and away the biggest challenge for NNSA is to make sure that the disposal system for transuranic waste is robust enough to not become a choke point for our mission,” McConnell said.
The Waste Isolation Pilot Plant is DOE’s only deep-underground disposal facility for transuranic waste. In order to operate the facility into the 2050s, the agency needs New Mexico to modify the site’s operating permit. As written, the permit requires the federal government to stop burying waste at the site in 2024, then spend a decade safely closing down the facility.
The NNSA plans in 2024 to start casting new war-ready plutonium cores for nuclear warheads at the Los Alamos National Laboratory in New Mexico. It expects to expand production to a combined 80 pits annually at Los Alamos and the Savannah River Site in South Carolina by around 2030. The associated waste stream from the mission will one day make the nuclear weapons agency the largest generator of transuranic waste in the Department of Energy complex.
That will not happen until 2038 or so, “so there’s time to figure out what this means, both in terms of management and availability of continued disposal,” McConnell said.
Transuranic waste, or TRU waste, is equipment and material contaminated with elements heavier than uranium, typically plutonium. Pits are the fissile cores of nuclear weapons, and the first to be cast later this decade will be for warheads to tip the planned fleet of Ground-Based Strategic Deterrent intercontinental ballistic missiles.
After starting production four years from now, the NNSA plans to produce 30 pits a year at Los Alamos starting in 2026, then 80 a year by 2030 by adding another 50 pits annually at the Savannah River Site.
Either site could, at least temporarily, handle all 80 pits on its own. In that 80-pit solo configuration, Los Alamos would annually generate a mixture of roughly 400 cubic yards (about 305 cubic meters) of transuranic and mixed transuranic waste. The NNSA projects Savannah River to generate more waste than that to produce just its nominal 50 pits a year: 1,365 cubic yards (or almost 1,045 cubic meters) of transuranic waste annually.
Casting 80 pits a year by using both factories would produce about 19,200 cubic yards, or some 14,680 cubic meters, of transuranic waste from 2030 to 2050, according to slides McConnell briefed at the conference.
He said the NNSA, together with DOE’s Office of Environmental Management, will begin a collaborative review “in the very short coming weeks” about the future NNSA TRU waste generator sites.