MERCURY, Nev. — The next U.S. laboratory for testing nuclear weapons without nuclear explosions will be done a year or two sooner but cost more than forecast this spring, officials said here Wednesday.
The officials spoke to the Exchange Monitor and other media outlets during a press tour of the Nevada National Security Site, organized by the Department of Energy’s National Nuclear Security Administration (NNSA): owner of the site and the civilian agency responsible for the upkeep of U.S. nuclear weapons.
Following this year’s rebaseline, a review that set new cost and schedule estimates, the already delayed U1a Complex Enhancements Project (UCEP) project at the Nevada site, where the U.S. used to blow up nuclear weapons, should be done between Oct. 1, 2026 and Sept. 30, 2027, said Roger Rocha, president of the site’s Honeywell-led prime contractor, Mission Support and Test Services.
UCEP should now cost a total of about $876 million, said Robert Bangerter, federal project director of NNSA’s Nevada Field Office.
That’s sooner than the NNSA’s previous public estimate, something Rocha attributed partially to delays with a scientific instrument the lab will host, but also more expensive. In March, as part of its 2025 budget request, NNSA said UCEP might be done by Sept. 30, 2028 and cost $762 million.
The changes disclosed this week are only the latest major adjustment for UCEP, conceived a decade ago and since troubled by what the NNSA has called “inadequate planning assumptions” and “poor quality” designs, which were submitted both late and in pieces.
In June 2022, when the NNSA published its first official baseline for UCEP, the agency thought it would take until sometime in 2026 to finish and cost about $560 million. That was a notable shift in expectations compared with the NNSA’s earliest estimates from 2014, when the agency officially declared that it needed UCEP and forecast that the facility could be finished by 2023.
The NNSA has fingered the current site prime, which has been on the job since 2017, for some of UCEP’s problems. Others the agency charged to subcontractors or supply chain wildness in the post-COVID years.
The latest schedule shift, however, also accounts for delays with the SCORPIUS x-ray imager that eventually will be installed in the underground lab, Rocha said this week. The instrument, designed by the Los Alamos National Laboratory in New Mexico, will not be ready until 2030 or so.
In 2022, the same year the Nevada site established UCEP’s first baseline, a senior Los Alamos official said SCORPIUS would probably arrive closer to 2030. The NNSA has since confirmed this.
On the other hand, Rocha said, another underground weapons-testing instrument, called the Z-Pinched Experimental Underground System (ZEUS), will be ready by 2027 or 2028.
ZEUS “already exists,” Rocha said this week, and is somewhere in the Nevada site’s Area 11. “It’s real, it’s done. It just needs to be brought underground.”
After that, Rocha said, “SCORPIUS will start being installed in parallel with the finishing [of] UCEP. So what we’ve done is aligned three different schedules.”
UCEP’s goal is to expand and make habitable a facility once called the U1a complex and now called the Principal Underground Laboratory for Subcritical Experimentation. In the lab, weapons personnel will use new instruments to monitor the explosive, but subcritical, plutonium tests the NNSA performs at the isolated desert site.
For about two decades, NNSA has used subcritical testing, along with historical data from the full-yield testing era and supercomputer simulations, to verify that deployed U.S. nuclear weapons are aging as expected and retain their designed destructive power.
The ability to maintain nuclear weapons without resorting to potentially provocative and environmentally hazardous full-yield explosive testing common during the Cold War is widely considered an international norm in most of the nuclear-armed world, including in Russia.
Exchange Monitor managing editor Dan Leone contributed to this story from Washington.
