The report by the Government Accountability Office, which acts as the investigative arm of Congress, challenges a three-decade-old fundamental of emergency planning around American nuclear power plants: that preparations for evacuation should focus on people who live within 10 miles of the site.
The GAO found that people living beyond the official 10-mile evacuation zone might be so frightened by the prospect of spreading radiation that they would flee of their own accord, clog roads, and delay the escape of others. The investigators said regulators have never properly studied how many people beyond 10 miles would make their own decisions to take flight, prompting what is called a "shadow evacuation."
As a result, the GAO report says, "evacuation time estimates may not accurately consider the impact of shadow evacuations."
However, Neil Sheehan, a spokesman for the federal Nuclear Regulatory Commission, shot back in an email statement: "We disagree with the view that evacuations cannot be safely carried out."
The investigation was requested by four U.S. senators: Democrats Barbara Boxer of California, Robert P. Casey Jr. of Pennsylvania and Sheldon Whitehouse of Rhode Island, and independent Bernard Sanders of Vermont. They asked for the report in 2011 in response to an Associated Press investigative series reporting weaknesses in community planning for nuclear accidents, including the likelihood of surprisingly large shadow evacuations.
In an interview Wednesday, Casey said the report suggests that "we need to do more to ensure that these residents who live outside of the 10-mile radius have access to and understand evacuation procedures." He said legislation may be needed but gave no details.
The disaster at the Fukushima Dai-ichi nuclear complex in Japan two years ago has heightened worry about how well U.S. communities can protect themselves from a major release of radiation. When a tsunami cut off power and nuclear fuel melted, more than 150,000 people fled the Fukushima area, many from well beyond 12 miles, according to Japan's Education Ministry. U.S. officials recommended that Americans in Japan stay 50 miles back.
Under federal rules, however, U.S. communities practice for evacuation or other protective action by residents only within 10 miles of nuclear power plants. States also lay plans to limit consumption of contaminated crops, milk and water within 50 miles.
Environmental and anti-nuclear groups have pressed federal regulators to expand planning to 25 miles for evacuation and 100 miles for contaminated food. They also want community exercises that postulate a simultaneous nuclear accident and natural disaster.
Nuclear sites were originally picked mainly in rural areas to lessen the impact of accidents. However, in its 2011 series, the AP reported population growth of up to 350 percent within 10 miles of nuclear sites between 1980 and 2010. About 120 million Americans — almost 40 percent — live within 50 miles of a nuclear power plant, according to the AP's analysis of Census data. The series also reported shortcomings in readiness exercises for simulated accidents, including the failure to deploy emergency personnel around the community, reroute traffic, or practice any real evacuations.
The series further documented how federal regulators have relaxed safety standards inside aging plants to keep them within the rules and avoid the need for shutdowns.
Asked about the GAO study, Paul Blanch, a retired engineer who has worked on nuclear safety for the industry, questioned whether it's even possible to plan for an effective, managed evacuation of residents in a very populated area. "I absolutely believe they would panic, and they'd clog the roads," he said.
Jim Riccio, nuclear policy analyst for the anti-nuclear group Greenpeace, seconded the GAO's skepticism about current shadow evacuation planning. "Greenpeace has looked at the NRC's emergency planning for a long time as being ridiculously unrealistic," he said. "It pretends that Americans are going to follow orders when it comes to emergency evacuation."
In a statement, Sen. Whitehouse said he hopes the GAO report "will spur additional action." He said it "shows that we can, and must, do more to prepare for nuclear disasters."
Federal regulators have recommended planning for the unsanctioned evacuation of 20 percent of the population between 10 and 15 miles away. But the GAO report said this recommendation may be faulty, because it's based on a survey of better-informed people within the official evacuation zone. The GAO said federal officials should study how people outside the 10-mile zone would respond to a nuclear emergency and incorporate this new perspective into standards.
In a response to the report sent before its release, the NRC staff said it had extensively studied shadow evacuations for hazards other than radiation and had concluded that traffic would be unimpeded in most cases.
In a letter attached to the report, R.W. Borchardt, the NRC's executive director of operations said the agency stands by the 10-mile standard for evacuation planning.
However, NRC spokesmen also pointed out Wednesday that senior agency experts, in a post-Fukushima report, have opened up the possibility of revisiting the 10-mile standard.
Kris Eide, Minnesota's emergency management director and a spokeswoman for the National Emergency Management Association, said she thinks the GAO's focus on shadow evacuation is misguided. She said it's more important to bolster preparations within 10 miles because sometimes "people inside a hazard zone don't even evacuate." She said the public should be enlisted to participate in exercises, which isn't required by federal standards.
Sean Kice, a radiation protection officer at the Tennessee Emergency Management Agency, backed the NRC standard and said his state's plans are "adequate enough to provide a safe evacuation."
Steven Kerekes, a spokesman for the industry's Nuclear Energy Institute, said in a statement that evacuation planning is just one element of the many defenses protecting the public near nuclear plants. He also referred to recent NRC research suggesting that nuclear accidents are apt to involve more time to evacuate and less radiation release than once believed.