Having heralded Japan's entry into the atomic age, a leading nuclear scientist has been left reeling by the crisis at the Fukushima No. 1 power plant.
Having heralded Japan's entry into the atomic age, a leading nuclear scientist has been left reeling by the crisis at the Fukushima No. 1 power plant.
Atsushi Kasai, a former laboratory chief at what is now the Japan Atomic Energy Agency, suggests that today's generations of scientists and plant operators may have been blinded by an overconfidence in Japanese technology, saying they must try to prepare for the unforeseeable.
He and other nuclear experts also called for a thorough review of the events that led to the accident, which was triggered by the March 11 Great East Japan Earthquake and subsequent tsunami, the worst natural disaster in Japan in modern history.
"Nuclear power has always had a dark side: nuclear weapons and accidents," Kasai said. "We have succeeded in passing on nuclear power technology from our generation to the next, but perhaps we failed to pass on the ability to think about that dark side."
Kasai joined the then Japan Atomic Energy Research Institute in 1959, just two years after Japan's first nuclear power reactor in Tokai, Ibaraki Prefecture, achieved a self-sustaining nuclear reaction.
He served as a safety assessment committee member at the International Atomic Energy Agency and took part in numerous field inspections following the Chernobyl nuclear power plant disaster in 1986.
While others have denied the possibility of such a crisis occurring, Kasai firmly believes there is "maybe a one in several million of a chance that the China syndrome could become a reality."
The China syndrome is a hypothetical situation in which a nuclear meltdown destroys a power plant, melting the core all the way through the Earth's crust and reaching the other side of the globe.
However, when he mentioned this to younger researchers, he was shocked by their reactions.
"The younger generation appeared to believe that nuclear accidents cannot occur--that's a myth," he said, recalling how they argued that such a situation was "impossible" and appeared confident that Japanese technology ranked top in the world.
Moreover, when he visited a Tokyo Electric Power Co. nuclear power plant as an instructor 20 years ago, he was startled to find that workers thought that "the actual work on the floor can be carried out by a small clique."
He started to worry that the younger generation "lacked an awareness that such a practice could lead to an accident."
Kasai also feels uneasy about TEPCO's failure to fully disclose information about the current problems at the Fukushima No. 1 plant.
He said that they had failed to provide data needed to accurately evaluate both the seriousness of the incident and the spread of radiation.
According to Kasai, nuclear power plants are obliged to set up radiation monitoring devices capable of operating without an electric power source. These devices keep a cumulative record of the radiation released after an accident.
Operators are supposed to retrieve that data when an accident occurs, but Kasai said the data has not been published.
He also said that data indicating how much fuel was being spent at the time of the accident has yet to be released.
"As one who has been involved in nuclear development since the beginning, I feel a certain responsibility," Kasai said.
He also said that if the situation stabilizes, he hopes to conduct contamination studies with like-minded colleagues.
Ayao Tsuge, president at the Shibaura Institute of Technology and a former technician at Mitsubishi Heavy Industries Ltd., who designed a type of nuclear reactor different from the ones at the Fukushima No. 1 plant, said he believed that Japanese engineers can "take pride in the fact that the reactors withstood the magnitude-9.0 quake and automatically shut down operations."
"We can only say that the earthquake and tsunami exceeded all expectations. Of course, those who designed the plant could be held accountable for the results caused by factors they had not taken into consideration."
Tsuge said that even after a power plant shuts down operations, there is a need to cool the reactor cores. He also said that nuclear power plants are equipped with a backup safety system, such as a diesel generator, that will kick in if the external power connection is severed.
"The fact that this multilayered, fail-safe system has broken apart, was, in itself, an unforeseeable disaster," he said, emphasizing that it will be necessary to start a chronological review of the orders and decisions made in the crisis.
Tsuge said workers must broaden their imaginations to consider just how powerful and unpredictable nature can be.
(This article was written by Mikiharu Sugiura and Manabu Sasaki.)