The chair of the U.S. Nuclear Regulatory Commission (NRC) today defended his advice that Americans living within 80 km of the stricken Fukushima Daiichi plant should leave their homes after the 11 March accident. Speaking in Washington, D.C., at the Forum on Science and Technology Policy sponsored by AAAS (which publishes ScienceInsider), Gregory Jaczko explained in general terms how the safety assessment was made but wouldn't address the charge that it confused Japanese citizens.
That advice conflicted with a safety perimeter of 30 km established by the Japanese government, and drew harsh criticism from a Japanese science policy analyst attending the forum. "Prior agreement" between the governments would have minimized what was a "huge confusion" for Japanese citizens, said theoretical physicist Hirotaka Sugawara of the Washington, D.C., office of the Japan Society for the Promotion of Science in a question to Jaczko. "What people started to do was mistrust the Japanese government."
Jaczko said that the NRC's definition of the danger zone was based on an analysis of the status of the Fukushima reactors and represented a "conservative estimate" of the risk from radioactivity. "It was meant to be a recommendation for U.S. citizens, not Japanese citizens," he said, adding that there were "dialogues" with Japanese authorities before the recommendation was issued.
Jaczko also deflected some responsibility onto the U.S. Embassy in Japan, to whom the NRC gave the recommendation. He said embassy officials made the final decision about what to say publicly.
Jaczko also offered some detail on two NRC studies of U.S. plants begun after the Fukushima accident occurred following the massive earthquake and tsunami. The first, a 3-month study to rapidly assess safety issues by NRC staff members, is holding its first public meeting next week. "We haven't seen anything [that indicates] there's an immediate change [needed] or immediate safety concern," said Jaczko of the first study, due out this summer. The second, longer term, study will involve various sectors of the public and industry.