The National Nuclear Security Administration (NNSA) greenlighted the start of full construction, or Critical Decision 2/3, for the High-Fidelity Training and Operations Center (HFTOC) at Savannah River Site.

The HFTOC will function as a training facility, or a mock facility, for the Savannah River Plutonium Processing Facility’s Main Processing Building, according to a Monday press release by Savannah River Site. The goal of the facility is to “mimic capabilities” of the Main Processing Building so operators can use “like-for-like” sets and surrogate materials to develop pit production competencies while the main building is still in development.

The project, which the site’s prime Savannah River Nuclear Solutions has subcontracted Kiewit for, the project expected to cost $1.4 billion, with expected completion in 2028. Operators can then train in the facility while waiting for the main plutonium facility to finish construction, the release said.

The Savannah River Plutonium Processing Facility will eventually work in tandem with Los Alamos to produce plutonium pits, or the fissile cores of a nuclear weapon, for the nation’s nuclear weapons stockpile.

In accordance with federal law, NNSA must be able to produce 80 or more pits yearly to replenish the nuclear stockpile, the release said. Savannah River is expected to make upwards of 50 once its Savannah River Plutonium Processing Facility completes construction at an expected date of 2035, and Los Alamos National Laboratory in New Mexico is expected to make upwards of 30. NNSA also expects SRPPF’s design to be 90% complete in 2026.

The aim for the plutonium processing facility was to finish the project in 2032, but the Critical Decision 1 estimate, or the original estimate, was a project completion range of 2032-2035. Scott Pappano, the principal deputy administrator for NNSA, said at Exchange Monitor’s Nuclear Deterrence Summit at the end of January that until the Plutonium Processing Facility is complete, Savannah River can still play a “supporting role” in pit production.

“The HFTOC at SRS [Savannah River Site] will be an important training facility used to accelerate the re-establishment of large-scale plutonium pit manufacturing in the United States,” Michael Mikolanis, Savannah River’s field office manager, said in the press release.

Los Alamos would initially make cores for the first stages of W87-1 warheads, which are to top the Air Force’s planned silo-based Sentinel missiles some time next decade. Savannah River will make cores for the W93 warheads, which the Navy will use in its submarine-launched ballistic missiles. The W93 warhead will begin production in the mid-2030s.