At the nation’s top nuclear weapons labs and plants, safety mishaps have imperiled life and limb, and hindered national security operations.  This Scientific American story is part of a one-year investigation by reporters at the Center for Public Integrity that reveals many problems and little accountability. In addition to the Nevada accidents, a near-fission calamity in 2011 at Los Alamos National Laboratory in New Mexico led to an exodus of nuclear safety engineers and a four-year shutdown of operations crucial to the nation’s nuclear arsenal. Yet penalties for these incidents were relatively light, and many of the firms that run these facilities were awarded tens of millions of dollars in profits—or even new contracts—after major safety lapses occurred.

Not a clue.

The government scientists didn’t know they were breathing in radioactive uranium at the time it was happening. In fact, most didn’t learn about their exposure for months, long after they returned home from the nuclear weapons research center where they had inhaled it.

The entire event was characterized by sloppiness, according to a quiet federal investigation, with multiple warnings issued and ignored in advance, and new episodes of contamination allowed to occur afterward. All of this transpired without public notice by the center.

Here’s how it happened: In April and May 2014, an elite group of 97 nuclear researchers from as far away as the U.K. gathered in a remote corner of Nye County, Nev., at the historic site where the U.S. had exploded hundreds of its nuclear weapons. With nuclear bomb testing ended, the scientists were using a device they called Godiva at the National Criticality Experiments Research Center to test nuclear pulses on a smaller and supposedly safe scale.

But as the technicians prepared for their experiments that spring—under significant pressure to clear a major backlog of work and to operate the machine at what a report called Godiva’s “upper energy range”—they committed several grievous errors, according to government reports.

The machine had been moved to Nevada nine years earlier from Los Alamos, N.M. But a shroud, descriptively called Top Hat, which should have covered the machine and prevented the escape of any loose radioactive particles, was not reinstalled when it was reassembled in 2012.

Also, because Godiva’s bursts tended to set off multiple radiation alarms in the center, the experimenters decided to switch the alarm system off. But because the alarms were connected to the ventilation and air filter system for the room, those were shut off as well. The only ventilation remaining was a small exhaust fan that vented into an adjacent anteroom where researchers gathered before and after experiments.

On June 16, 2014, a month after the experiments were completed, technicians doing routine tests made an alarming discovery—radioactive particles were in the anteroom. They then checked the room holding Godiva, and found radiation 20 times more intense there. The Nevada site’s managers, who work for a group of private, profit-making contractors—like most U.S. nuclear weapons personnel—ordered the rooms decontaminated. But they didn’t immediately check exposures among the scientists and researchers who had gathered for the tests, many of whom had already gone back to their own labs.

None had any clue about the mishap until two months after the experiments, on July 17, when one of them—a researcher from Lawrence Livermore National Laboratory nuclear weapons lab in California—got the results from his routine radiation monitoring. His urine tested positive for exposure to enriched uranium particles.

National Security Technologies,, LLC (NSTec), the lead contractor that runs the Nevada site, subsequently collected urine specimens from its own workers who’d been in the room with Godiva during the experiments. It discovered three of its technicians also had inhaled highly-enriched uranium.

News of trouble spread–but only among the scientists and their bosses, who were accustomed to a shroud of official secrecy covering their work. No public announcement was made. According to an initial U.S. Department of Energy (DoE) investigative report dated April 28, 2015, calls eventually went out to test the 97 people present for the Godiva experiments. But for reasons that remain unclear the testing went very slowly, and not until 2016 did the DoE state that 31 were discovered to have inhaled uranium.

In a letter last summer to the Los Alamos and Nevada lab directors, National Nuclear Security Administration (NNSA) Administrator Frank Klotz suggested that the employees’ radiation doses were not large—at the high end, they were roughly equivalent to 13 chest x-rays. But once inhaled, uranium particles can keep emitting radiation for years, and so they pose an added cancer risk. Klotz’s letter deemed the exposures “safety-significant and preventable.” It could have been even worse, of course, given the absence of any timely warning.

LAB OPERATIONS RIDDLED WITH ERRORS

The four key national facilities involved in the underlying experimentation—Los Alamos National Laboratory, Lawrence Livermore, the Nevada Test Site and Sandia National Laboratory—are among the U.S.’s premier scientific labs. They collectively employ more than 26,000 people engaged in cutting-edge and often dangerous work, governed by myriad nuclear safety regulations, with two major contract enforcement mechanisms meant to inflict financial pain when needed on the private corporations that operate them.

And yet in this case, and in others like it, not only were the labs’ procedures and responses riddled with errors, but even after attention was called to these incidents, other safety mishaps occurred. And the financial penalties imposed by the government didn’t seem to have a major impact on the labs’ conduct.

A review by The Center for Public Integrity (CPI) of more than 60 safety mishaps at 10 nuclear weapons–related federal sites that were flagged in special, internal reports to Washington, along with dozens of interviews of officials and experts, revealed a protective system that is weak, if not truly dysfunctional: Fines are frequently reduced or waived while contractors are awarded large profits. Auditors say labs and production plants are overseen by an inadequately staffed NNSA and DoE, which as a result largely rely on the contractors to police themselves.

The CPI probe, partly based on documents obtained under the Freedom of Information Act, reveals a system in which extra profit is awarded under a rating profile that persistently places higher priority on the nuclear weapons labs’ national security “mission” than on worker protections, putting production far ahead of safety. Experts say it is a practice in keeping with a culture of urgent, no-holds-barred work that took root in the nuclear weapons complex during World War II. These production pressures flow down to the highly secured rooms where workers labor with special clearances, routinely handling highly toxic and explosive materials……..

A WORKPLACE HAZARDOUS TO WHISTLE-BLOWERS……