Tougher U.S. nuclear-power regulations may be needed because government inspectors and companies underestimated the dangers of natural disasters, said Gregory Jaczko, chairman of the Nuclear Regulatory Commission.
Before a March 11 earthquake and tsunami crippled a Japanese plant, regulators and industry officials thought they would “never see an event like this,” Jaczko said today during a meeting at NRC headquarters in Rockville, Maryland.
U.S. regulators believed existing disaster plans “had done everything to basically take this type of event completely off the table,” Jaczko said. “Obviously we haven’t.”
Commercial U.S. reactors are under scrutiny after a magnitude-9 temblor and subsequent tsunami knocked out power and backup generators at Tokyo Electric Power Co.’s Fukushima Dai-Ichi plant, about 135 miles (217 kilometers) north of Tokyo. Without electricity, cooling systems failed and fuel rods overheated, causing fires, explosions and radiation leaks in the worst nuclear incident since the 1986 Chernobyl disaster.
U.S. reactors are safe and plant owners have boosted their “readiness capability and training” for disasters, “regardless of their cause,” Steve Kerekes, a spokesman for the Nuclear Energy Institute, said in an e-mail today. The industry created a post-Fukushima safety panel to weigh additional changes, Kerekes said.
“We fully recognize there are years of work ahead to learn lessons from the events in Japan and to apply them as warranted,” he said.
The NRC has released inspection reports from a 90-day reactor safety review that began March 23. Inspectors determined whether U.S. plants are ready to keep radioactive fuel rods from overheating and melting after “extreme events,” such as natural disasters and terrorist attacks. The task force leading the review is to issue a report next month.
The NRC also examined the industry’s voluntary “severe accident” plans for bringing reactors under control if a meltdown can’t be prevented.
The NRC inspectors have so far concluded that U.S. nuclear plants are meeting safety regulations, with some flaws in their disaster-response preparations.
Almost one in five plants needed to improve plans for preventing meltdowns after large fires, explosions, electricity blackouts or extreme floods, the NRC said on May 13. While all nuclear plants have severe-accident guidelines, almost two in five don’t carry out drills on bringing a meltdown under control, according to an NRC statement on June 6.
At today’s meeting, Jaczko criticized the scope of regulations focused on the ability of nuclear plants to cope without electricity from the power grid or emergency generators. Current rules require most operators to plan for a “station blackout” of four to eight hours’ duration, Jaczko said.
Even before the Japan disaster, there was “pretty clear and obvious evidence that that’s not sufficient,” he said.
Charlie Miller, the NRC official leading the safety review, said agency officials are examining station-blackout rules and said “it might take days to restore” electricity to a plant after some disasters.
Miller also said reactor-owners’ plans for bringing a meltdown under control after a severe accident didn’t get “rigorous oversight” from the NRC before the crisis in Japan because they were voluntarily developed by nuclear plants in the 1990s.
“There isn’t a specific inspection requirement,” he said.
Agency officials “still have high confidence that the plants are safe to operate” amid the flaws found during inspections, said Bill Borchardt, the NRC executive director for operations and Miller’s boss.
The NRC should halt “all new nuclear reactor and design licenses and license extensions for existing reactors” until tougher rules are imposed for “catastrophic events or even simple power outages,” U.S. Representative Edward Markey, a Massachusetts Democrat, said in an e-mail.