The head of the Fukushima No. 1 nuclear power plant was at a total loss on what to do when the crisis started on March 11.
The head of the Fukushima No. 1 nuclear power plant was at a total loss on what to do when the crisis started on March 11.
But only for a moment.
Masao Yoshida then went into action and became a key player in the battle against the unprecedented accident at his plant.
The interim report issued on Dec. 26 by the government panel investigating the nuclear disaster reveals some of the thoughts and actions of Yoshida.
Around 3:30 p.m. on March 11, a tsunami wiped out the power sources to the Fukushima plant.
"The situation went way beyond any severe accident that I had considered until then, and for an instant I had no idea what to do," Yoshida is reported as saying.
Yoshida was in the emergency response room when the tsunami hit. At 11:50 p.m., Yoshida realized the cooling equipment for the No. 1 reactor was not working.
"I was overwhelmed from the information that kept coming in continuously and I had lost the luxury of making a comprehensive judgment about related important information," Yoshida said, according to the report.
At 12:06 a.m. on March 12, Yoshida gave instructions to prepare for venting to reduce the pressure in the containment vessel of the No. 1 reactor. Venting required work indoors where radiation levels were high.
Yoshida told workers on duty at that time, "Although you will likely be exposed to a considerable amount of radiation, I want you to go to the site for manual operations."
On the evening of March 14, the cooling mechanism for the No. 2 reactor also began experiencing problems.
"Left unattended, melting of the core will proceed and the situation could lead to a so-called China syndrome," Yoshida said.
He decided to have workers evacuate from the plant while leaving behind only those absolutely necessary. To prevent panic, Yoshida gave instructions to a limited number of individuals to arrange for buses to take the workers away.
On the morning of March 15, an explosion occurred at the No. 4 reactor. When Yoshida heard a report about an impact sound from the No. 2 reactor, he instructed the workers to evacuate.
About 650 were evacuated temporarily to the Fukushima No. 2 nuclear power plant, leaving about 50 workers at the crippled plant.
Yoshida was relieved of his post in November to allow him to take sick leave. It was later disclosed that he had been diagnosed with esophagus cancer. Officials of Tokyo Electric Power Co., the operator of the Fukushima plant, said the disease was not likely caused by radiation exposure during emergency operations.