A government panel investigating the Fukushima nuclear crisis is expected to state in an upcoming report that the evacuation order issued shortly after the accident began was irrational, sources said.
The government ordered people living within 20 km of the plant to evacuate, but the panel believes the order led some residents to move to areas where radiation was actually higher and created mass confusion, the sources said.
The prime minister’s office received its first fallout estimate on March 23 — or 11 days after the first hydrogen explosion occurred at the Fukushima complex. The estimate was based on data from the government’s special computerized System for Prediction of Environmental Emergency Dose Information (SPEEDI).
The nuclear safety agency and the science ministry had SPEEDI data that could have prevented some of the unnecessary radiation exposure, but decided to sit on it instead of reporting it to the crisis management center at the prime minister’s office, the sources said.
Their thinking, according to the sources, was that the data were “merely a hypothetical calculation result.”
As a result, people who fled the coast of Fukushima Prefecture and went northwest ended up in places where the danger was higher because spring winds at the time were blowing in that direction, carrying toxic fallout to areas well beyond the 20-km radius evacuation zone, they said.
That situation occurred because the government issued the evacuation order based only on distance, the sources said.
They said data from a costly high-tech system designed to predict the dispersal of radioactive materials could have served as a reference for evacuation because, although the amount of radiation was not accurately predicted, it provided a clear picture of areas with relatively higher or lower radiation levels.
The panel, led by Yotaro Hatamura, a professor emeritus at the University of Tokyo who studies industrial accidents, is expected to release its interim report on the accident Monday.
Stricter food rules
A task force under the health ministry’s food sanitation council approved a proposal Thursday to reduce the top limit on radioactive cesium in food to 100 becquerels per kilogram for rice, meat, vegetables and fish, one-fifth of the provisional 500-becquerel limit set after the Fukushima disaster began.
The ministry plans to enforce the new limits in April. The government said Dec. 17 it had achieved a cold shutdown of the crippled reactors at the Fukushima No. 1 power plant and that they were no longer emitting high amounts of radiation.
The proposal calls for setting a limit of 50 becquerels of cesium per kilogram of milk and food for infants, including powdered milk, and a 10-becquerel limit on drinking water, compared with the 200-becquerel limit set by the government following the core meltdowns in Fukushima in March.
But “grace periods” of between six and nine months will be set for such items such as rice and beef.
The Health, Labor and Welfare Ministry will refer the proposal to the science ministry’s radiation council and hold briefing sessions in seven prefectures, including Fukushima, Tokyo and Osaka, starting in January and seek public comment.