Ashley Siefert Nunes
WASHINGTON—Newly released results of an investigation conducted by the U.S. Nuclear Regulatory Commission (NRC) at the Quad Cities nuclear plant in Illinois reveal a shocking coverup by plant personnel. The investigation confirmed that a “willful failure” by a reactor operator to implement a critical procedure when initiating a full manual insertion of the control rods during a March 2023 refueling outage resulted in a failure to close 177 open valves, allowing cooling water to rapidly flow out of the Unit 1 reactor pressure vessel. While this “drain down” error was resolved in six minutes, had the event not been terminated the water level would have dropped below the top of the radioactive fuel in the vessel in about 15 minutes. Furthermore, two personnel at the plant were sprayed with radioactive coolant water but were not appropriately surveyed and decontaminated afterwards.
Although other safety systems remained available to mitigate such an event, this was a significant precursor to a major accident with the potential for core damage and radiological release. The “shutdown safety” status during the event was RED, the highest risk category. The 2011 Fukushima Daiichi disaster in Japan, which contaminated hundreds of square miles with long-lived radioactivity, involved reactors of the same design as Quad Cities.
Following the event, a licensed senior reactor operator willfully failed to report the occurrence of the drain down event to NRC inspectors and lied about its cause for 10 days before finally coming clean and correcting their original report. But even then, plant personnel failed to accurately document how close the reactor came to a meltdown, leading the NRC to misjudge the seriousness of the event. The plant owner, Constellation Energy, did not provide public notice of the event until January 2025—nearly two years after it occurred—and likewise played down its significance. In all, the NRC investigation confirmed six violations associated with the incident but has yet to make an enforcement decision.
Below is a statement by Dr. Edwin Lyman, the director of nuclear power safety at the Union of Concerned Scientists (UCS).
“This disturbing near-miss and coverup at the Quad Cities nuclear plant demonstrates why the United States needs an independent, fully present and well-resourced nuclear safety regulator. Unfortunately, nuclear plant managers cannot be relied on to police themselves. The Trump administration should give the NRC all the tools it needs to be effective at safeguarding communities from potentially catastrophic nuclear plant disasters instead of trying to render it toothless by making it subordinate to business interests.”
In addition to Dr. Lyman, UCS also has Midwest experts available to speak about the need to modernize the region’s electricity grid infrastructure and bring more renewable energy online. To speak to Dr. Lyman or another UCS expert, please contact UCS Climate and Energy Media Manager Ashley Siefert Nunes.