All cooling water has drained from the spent-fuel pool at one of the crippled nuclear reactors in Japan, causing the release of high levels of radiation, U.S. Nuclear Regulatory Commission Chairman Gregory Jaczko said.
“We believe that the secondary containment has been destroyed and there is no water in the spent-fuel pool,” he said today at a hearing of a House Energy and Commerce Committee panel in Washington. “We believe that radiation levels are extremely high, which could possibly impact the ability to take corrective measures.”
The unit at the Fukushima Daiichi plant wasn’t operating at the time of the March 11 earthquake and tsunami, said Jaczko, the chief U.S. regulator of nuclear-power plants.
The Associated Press reported that Japanese officials denied all the water has drained and said the reactor, known as Unit 4, is stable.
Radiation at the Japanese site is fluctuating and at peak levels is life-threatening, Jaczko said.
The peak levels “would be lethal within a fairly short period of time,” he said. The pool at the plant’s Unit 3, which was in service, may be cracked and losing water, Jaczko said.
U.S. citizens in the area have been urged to evacuate to 50 miles (80 kilometers) from the plant site, the same distance in the event of a nuclear accident in the U.S., Jaczko said.
“We would recommend an evacuation to a much larger radius than has currently been provided by Japan,” Jaczko said.
The NRC has 11 officials in Tokyo helping the Japanese government respond to the nuclear crisis. Japanese officials are injecting seawater into three reactors to try to keep them cool, Jaczko said.
The earthquake and tsunami in Japan crippled Tokyo Electric Power Co.’s Fukushima Daiichi nuclear plant with explosions, fires and radiation leaks. The containment vessels for the three operating reactors are reportedly functional, Jaczko said.
Jaczko said U.S. nuclear plants remain safe, and harmful radiation from damaged reactors in Japan isn’t expected to reach the U.S. The U.S. power plants are designed to withstand natural disasters, including earthquakes and tsunamis, Jaczko said.
“At this time we don’t have any specific actions that are necessary to add to the safety” of U.S. reactors, he said. A “thorough and systematic review” will be conducted after the Japanese crisis passes for possible additional actions, he said.