The Savannah River Site in South Carolina will produce at least half the plutonium pits for the Navy’s W93 warhead after the facility opens next decade, a federal official said Wednesday.
“We don’t think we can get that facility up in time to do all of the W93 builds, but it’s important that we have a fair number of those new pits,” Jill Hruby, administrator of the National Nuclear Security Administration (NNSA) said in a Senate Armed Services Committee hearing Monday.
Without new pits for W93, NNSA’s other option is “to reuse pits, which introduces some uncertainty but more importantly … it limits what else we can do in our stockpile when we reuse those pits,” Hruby said.
The NNSA administrator’s testimony, in response to a question from Sen. Angus King (I-Maine), confirms that the W93, the warhead for a planned submarine-launched ballistic missile that will replace the Trident II-D5 some time next decade, will get new pits.
Hruby testified in the Wednesday morning hearing alongside Secretary of Energy Jennifer Granholm.
NNSA notionally plans to produce its first proof-of-concept W93 warhead in the mid-2030s, right around the time Hruby forecast the Savannah River Plutonium Processing Facility would open.
According to NNSA’s fiscal year 2025 budget request, the agency planned to complete W93’s Weapon Design and Cost Report, which includes rough cost and schedule estimates, in fiscal year 2026 and stage test flights of the weapon between fiscal years 2027 and 2029. The agency requested more than $455 million for W93 for 2025.
The Savannah River Plutonium Processing Facility, the larger of NNSA’s two planned pit factories, should be finished in 2032, Hruby said Wednesday, but it will take “a few more years” after that before the facility is ready to cast plutonium pits, the fissile cores of a thermonuclear weapon’s first stage.
In its 2025 budget request, the NNSA said the Savannah River pit plant could cost as much as $25 billion to build. That’s more than twice as high as the agency’s top-end estimate from a year ago. The agency planned to create a formal cost and schedule baseline for the facility in fiscal year 2026, according to the 2025 request.
The NNSA’s other plutonium pit factory will be at the Los Alamos National Laboratory in New Mexico, which will initially manufacture new pits for the W87-1 warhead to be used on future Sentinel missiles, the Air Force’s next silo-based intercontinental ballistic missile and a replacement for the service’s current Minuteman III missiles.
Los Alamos will start making pits for W87-1 warheads this year and ramp up to 30 annually by 2028, Hruby said Wednesday.
