It was “extremely inappropriate” for a government nuclear regulator to first imply and then later deny possible nuclear reactor core meltdowns in the wake of the crisis at Tokyo Electric Power Co.’s Fukushima No. 1 nuclear power plant, a government panel said Monday.
The panel probing Japan’s worst-ever nuclear crisis also said in its final report that “there was room to utilize” the System for Prediction of Environmental Emergency Dose Information (SPEEDI), which is designed to aid resident evacuation by predicting radiation diffusion.
The panel found the Nuclear and Industrial Safety Agency’s methods of releasing information to the public to be particularly problematic.
In a news conference on March 12, 2011, then NISA spokesman Koichiro Nakamura, the deputy director general for nuclear safety, mentioned the possibility of meltdowns.
The Prime Minister’s Office, which had not been informed of this development, then asked NISA to brief the office before making any announcements.
As a result, NISA representatives sought to avoid using the word “meltdown” in subsequent explanations.
On March 14, however, then spokesman Hidehiko Nishiyama referred to the possibility of meltdowns, while another NISA official at the same news conference denied it, saying the reactors were never believed “to be at the meltdown stage.”
However, at the time there was a consensus within the agency that meltdowns had almost undoubtedly occurred at the reactors.
The government panel’s final report said the NISA official’s comment was “incomprehensible” and the way the information was publicly released was “obviously wrong.”
During the accident, meltdowns occurred at three reactors and huge amounts of radiation were released after hydrogen explosions damaged some buildings containing reactors.
The report also said then Chief Cabinet Secretary Yukio Edano “should have avoided” repeatedly stating radiation levels “would not immediately have an impact on human health” in his explanations. The phrasing of Edano’s remark was unclear as to whether there was “no need to worry” or there “would be an impact in the long term,” the report said.
A parliamentary investigation panel on the crisis said earlier this month that the SPEEDI system was difficult to use in the event of a quickly developing crisis, but the latest government panel report said there were opportunities to use it.
“There was a possibility of using the results to offer times and directions for evacuating residents,” the report said. It added that related agencies in charge of operating the system and releasing information should have discussed how to use the system in advance.
This website updates the latest news about the Fukushima nuclear plant and also archives the past news from 2011. Because it's always updated and added live, articles, categories and the tags are not necessarily fitted in the latest format.
I am the writer of this website. About page remains in 2014. This is because my memory about 311 was clearer than now, 2023, and I think it can have a historical value. Now I'm living in Romania with 3 cats as an independent data scientist.
Actually, nothing has progressed in the plant since 2011. We still don't even know what is going on inside. They must keep cooling the crippled reactors by water, but additionally groundwater keeps flowing into the reactor buildings from the broken parts. This is why highly contaminated water is always produced more than it can circulate. Tepco is planning to officially discharge this water to the Pacific but Tritium is still remaining in it. They dilute this with seawater so that it is legally safe, but scientifically the same amount of radioactive tritium is contained. They say it is safe to discharge, but none of them have drunk it.