Tsunami expectation and Final Report
Kenji IinoThe Feb. 7, 2016 morning edition of Nikkei posted an article titled "Road to recovery (6): Was Fukushima beyond expectation?" The article started as follows:
"TEPCO's Fukushima Daiichi Nuclear Power Plant (NPP), flooded with the water from tsunami, lost its cooling function for the nuclear reactor and its core melted. Was the accident really beyond expectation? If TEPCO had prepared the plant with discreet judgement, the accident could have been contained."
The tsunami preparation study group of the Association for the Study of Failure (ASF) had reached the same conclusion with the Nikkei reporter. Moreover, IAEA in its final report  clearly stated that the huge tsunami was predictable.
Our study group, after reviewing the Furukawa paper  that raised the question, started with Motoharu Furukawa, Ritsuo Yoshioka, Masao Fuchigami, and myself, Kenji Iino to find answers to the questions:
Yoshioka reported the results in the 2015 Winter Annual Meeting of ASF with a heavy comment:
"As IAEA stated in its final report, the earthquake and tsunami expectations at Fukushima Daiichi did not meet the international IAEA standards."We revised our 2015 report, and here is the summary:
Report: "Fukushima Nuclear Power Plant Tsunami Preparation Study Group"
Feb. 1, 2016
ASF tsunami preparation study group
The Atomic Energy Society of Japan (AESJ) monthly journal ATOMΣ reported in its March 2015 issue about activities related to the Fukushima Nuclear Power Plant accident by academic societies. Further in its September issue, it declared its intension to "cooperate with other academic societies." This September article quoted ASF's opinion that "In addition to analyzing the accident, we should construct a rich knowledge basis by studying what actions, different from the actual course of events, could have been taken to lead to success and not failure."
There are as many as 10 investigation reports about Fukushima NPP accident, however, they all discuss the "process of how the accident developed" and none explains "If there was a way to avoid failure."
ASF carried out 4 Forums since February of 2014, and through the discussions organized "Study on tsunami preparation at Fukushima NPP" in April and June of 2015. The studies were aimed at clarifying answers to the following two questions. Details of our conclusion in on our home page (currently only in Japanese) .
Question 1: Was the huge tsunami predictable?
We list notable events along the time scale:
Question 2: How the severity of the accident could have been avoided?
The direct cause of the Fukushima NPP accident was the simultaneous loss of AC power, DC power, and ultimate heat sink.
If the following minimum preparations were made at the plant, the nuclear accident could have avoided its severity. The most demanding task is to manually hook up DC power to RCIC and HPCI after recognizing the loss of AC and DC power, and the remaining procedures have some options with time slack.
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