The science ministry provided data on the radioactive fallout to U.S. forces a few days after the crisis erupted at the Fukushima No. 1 nuclear plant — far earlier than the public was informed, a ministry official said.
After the crisis at the Fukushima plant began, the government could not use SPEEDI as originally anticipated because data on the amount of radioactive substances released from the plant proved inaccurate.
However, the science ministry and the government’s nuclear safety agency generated data by assuming the amount of radioactive substances — which could have helped local governments and people to choose more appropriate evacuation routes.
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