The Lessons from Fukushima
It’s now almost three months since the earthquake and tsunami hit Japan’s northeast coast on 11-March. Recently, IEEE Spectrum’s Eliza Strickland interviewed Tsuneo Futami, Superintendent of the Fukushima Dai Ichi plant from 1997 to 2000, on the events at Fukushima following the tsunami…
Futami: … TEPCO’s civil engineering group estimates the maximum tsunami risk and maximum earthquake risk for each power plant site. I was informed the maximum tsunami at the Fukushima Dai‑1 site might be 10 meters. The turbine buildings and the reactors were built 10 meters above the sea level, so it is beyond my imagination that seawater flowed into the turbine buildings of all units, and that facilities on the basement floor were flooded. …
The fact that TEPCO had already estimated that there was a likelihood of a 10 meter tsunami at this site and yet allowed the seawall to be built only 5.7 meters high raises some serious questions in this reader’s mind. Even with the turbines and reactors built above this level, the critical final stages of the cooling system were in the seaward yard, protected by a seawall that was little more than half as high as it needed to be. New information shows that the actual tsunami height may have topped 15 meters, three times the height of the seawall at the plant, and 5 meters higher than the turbines and backup generators.
I think that the Fukushima nuclear disaster should be a wake up call to all of us who are involved in risk assessment, reminding us to take seriously every risk we find, even those that seem negligible. Understanding our personal biases, including those of our employers. Disasters of the scope of Fukushima are not unimaginable, but they can get lost in our blind-spots!
29-May update – A major tornado is now heading for Japan, and TEPCO has stated that the Fukushima plant is not ready for the storm. They are concerned that more radiation will be spread by the storm.
Learn more about what happened at the plant:
TEPCO releases undisclosed data on nuclear crisis