Google Wants to Restart a Nuclear Reactor for a Data Center. Some Iowa Doctors Say, ‘Not So Fast.’

Like most big tech companies investing heavily in data centers for AI, Google has been busy planning massive new sites for its resource-hungry enterprises.

And like some, such as Microsoft, it also seeks to tap into nuclear power to meet a data center’s huge energy demands.

After looking around, Google last year reached a deal with the power company NextEra to take the mothballs out of a closed plant —the Duane Arnold Energy Center near Palo in Linn County, Iowa—reversing earlier work to shut it down after damage during a massive storm in 2020.

A group of Iowa doctors has stepped up to object. Federal regulators are hearing them out.

The physicians, under the banner of Physicians for Social Responsibility Iowa, took their fight to the Nuclear Regulatory Commission on Aug. 13, appearing before three federal administrative judges. The group argues the restart is too risky — and points to an analysis by its expert finding that infant health in the area improved after the plant shut down.

“I am not confident that Duane Arnold can be successfully restarted,” Dr. Maureen McCue, president of Physicians for Social Responsibility Iowa, wrote in a sworn declaration supporting the group’s petition.

Then the artificial intelligence boom rewrote the math. On Oct 27, 2025, NextEra and Google announced a 25-year agreement for Google to buy about 615 megawatts from a restarted Duane Arnold. The electricity would power a data center campus beside the plant, consuming the great bulk of what the reactor generates.

The plant had already been shut down. Shutdowns are not as simple as flipping a switch; there is much work, including removing fuel. No plant that has been decommissioned has ever been restarted in the U.S., although Constellation Energy – after a power purchase agreement from Microsoft – is working to restart the old Three Mile Island nuclear plant. It, too, is a work in progress and it, too, has had opposition.

Google plans on buying power from Duane Arnold as what NextEra calls “a 24/7 carbon-free energy source to help power Google’s growing cloud and AI infrastructure in Iowa” — the kind of firm, round-the-clock electricity that wind and solar alone can’t guarantee and that AI data centers increasingly demand. For Google, Duane Arnold is one piece of a wider nuclear push to power AI — it has separately agreed to buy 500 megawatts from Kairos Power’s advanced reactors by 2035.

NextEra is targeting the first quarter of 2029 for Duane Arnold’s restart. The company has asked the Nuclear Regulatory Commission for an exemption and three license amendments. It also submitted an environmental report concluding that the restart would have no significant environmental impact.

Fighting the effort is Physicians for Social Responsibility Iowa, an intervenor in the NRC proceeding. The group is represented by Wallace L. Taylor, a Cedar Rapids attorney who told the board he lives about 10 miles from the plant. “This is sort of personal for me,” Taylor said at the NRC hearing.

In sworn declarations, McCue and Dr. John Rachow, a physician and PSR Iowa member, both listed the same Oxford address, 26.1 miles from the plant. “I am concerned for my health and safety if Duane Arnold is allowed to restart,” McCue wrote. Rachow wrote, “I am afraid that if Duane Arnold is restored to operability there could be incidents or accidents resulting in radiation releases.”

The doctors raised five challenges to NextEra’s plan. At its Aug. 13 hearing, members of the Atomic Safety and Licensing Board pressed the parties on whether any challenge deserved a full hearing. Lawyers for NextEra and the NRC staff argued that none did.

The doctors’ objections gather around two ideas. First, the group says there is no legal framework for moving a plant out of decommissioning and back into operation. “There’s no legal or regulatory basis for restarting a closed nuclear plant in decommissioning status,” Taylor told the board. Second, the group says NextEra’s environmental review is impermissibly “segmented.”

NextEra evaluated the reactor as though it would operate in isolation. In reality, the doctors argue, its purpose is to power an adjacent Google facility that will draw “100 percent or at least a very, very large share” of the local electricity and groundwater. Analyze the reactor without the data center, their argument goes, and you have analyzed a fiction.

NextEra and the NRC staff pushed back, relying on a 2025 U.S. Supreme Court decision, Seven County Infrastructure Coalition v. Eagle County. The court held that an agency need not examine the environmental effects of a separate project it has no authority to regulate. Because the NRC does not license data centers, government lawyers said, Google’s campus lies outside its environmental review, no matter how tightly the projects are bound by contract.

They also argued that the commission has walked this path before. At the Crane Clean Energy Center, formerly Three Mile Island Unit 1, Constellation is pursuing a restart under a 20-year power agreement with Microsoft. NextEra asked the board to reject the doctors’ hearing request in full, and the NRC staff agreed. The judges took the matter under advisement and said a written ruling would follow.

Almost entirely unspoken in the legal argument was why a doctors’ group was in the room at all. As the board noted, the petition contains no traditional plant-safety challenge — no allegation of a specific equipment flaw or accident risk. Its health concerns sit just outside the National Environmental Policy Act questions the board agreed to consider.

Those concerns include a number of reasons, including a Sep 23, 2025, analysis by epidemiologist Joseph Mangano of the Radiation and Public Health Project. Mangano examined local health data from before, during and after Duane Arnold’s operating life.

Among residents of Benton and Linn counties ages 0 to 39, Mangano reported that the cancer incidence rate was 6.5 percent below the statewide rate before the reactor began operating, from 1969 to 1974. He said the local rate then climbed above the Iowa rate in the decades that followed.

Of 3,089 cancers diagnosed locally in that age group from 1975 through 2022, Mangano calculated that 482 — about 15.6 percent — exceeded the number predicted by the area’s earlier, lower rate. The calculation is central to his warning, but it does not by itself establish causation.

His post-shutdown figures cut in the same direction. In the five years after Duane Arnold closed in 2020, Mangano reported that infant mortality in Johnson and Linn counties fell 17.8 percent, compared with a 2 percent national decline. Premature births in those counties dropped 20.5 percent while rising 4.5 percent elsewhere in Iowa, and births under 1,000 grams fell 14.5 percent.

Mangano’s implication is that the reactor’s operation coincided with worse outcomes for the youngest and most vulnerable residents, while its closure coincided with better ones. A restart would test that argument in reverse. It is also the kind of claim the NRC’s environmental process is not designed to decide, which is part of the doctors’ frustration.

What the group ultimately wants is a full environmental impact statement: a broader review that brings the Google data center’s water and energy demands into the picture and updates climate and water data that are more than a decade old. What NextEra and the government want is to keep the restart on the schedule Google is counting on.

Duane Arnold is one of three U.S. reactors being pulled back from retirement to feed the computing boom, and the first that a group of physicians has tried to stop. The board’s ruling will decide whether that fight gets a hearing or ends at the threshold.

NextEra contended during the session with the NRC that environmental reviews already included in their plan should suffice.

At precisely the same time they defended their plans against PSR Iowa, whose physicians argue that Duane Arnold is unsafe, NextEra officials were dealing with a separate issue more than a thousand miles away. In Florida, its Saint Lucie 1 nuclear power plant was shut down unexpectedly as control rods dropped into its core.

A spokesman for Florida Power & Light, which is owned by NextEra and which operates Saint Lucie 1, said “operators followed their safety procedures to manually shutdown the reactor. Our experienced operators are following their established procedures to ensure all systems are functioning as designed. St. Lucie’s No. 1 commitment is to the safe and efficient operation of the plant.”