Eleventh Bieleschweig Workshop, Bielefeld, 3-4 August 2011

The Fukushima Accident and Systems Prone to EUE

Senate Meeting Room (Senatssaal) A3-126, University of Bielefeld

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The book arising from this Workshop, The Fukushima Dai-Ichi Accident, Peter Bernard Ladkin, Bernd Sieker and Christoph Goeker, eds., is now available (December 2013) from the publisher, LIT Verlag WebShop (please note there is a button on the WWW site for English-language and German-language pages). It includes longer articles on both engineering and risk issues by Lee Clarke, John Downer, Peter Bernard Ladkin, Stephen Mosley, Charles Perrow, Volkmar Pipek and Gunnar Stevens, Bernd Sieker and Stefan Strohschneider and is dedicated to Hal Lewis, one of the pioneers of accurate risk assessment of nuclear-power technology.

The mature versions of the papers presented at the Workshop are included in the proceedings, above. Additional material which does not appear in the proceedings is linked below.

On March 11, 2011, the Tohoku earthquake took out the primary power supply for the Fukushima Dai-ichi nuclear power plant on the east coast of Japan. Less than an hour later, the tsunami caused by the earthquake flooded the plant and the backup generators ceased functioning. This is called a station blackout. Tertiary power is supplied for a few hours by batteries. An electricity supply is needed in order to keep the cooling systems running; a running reactor or one in cold shutdown requires continual cooling. Thus started the most severe nuclear accident in a quarter century and one of the two most severe ever.

From a purely technical point of view, the accident can be characterised by the physical necessity of cooling active and spent nuclear fuel and the difficulty of doing so, caused partly by the inability to do so using foreseen methods and the consequent physical distortions such as core meltdown.

From a broader social point of view, the accident may be characterised by the lack of operational foresight into foreseeable events (it is by now uncontroversial that a tsunami event sufficient to top the seawall at Fukushima Dai-ichi was foreseeable), and the extremely severe consequences. A station blackout unrecoverable by foreseen procedures may be characterised as an Extreme Unsafe Event (EUE). The Japanese Government has set initial recovery costs from the accident at some €70 billion, which contrasts with the €20 billion set aside by BP as compensation for the Deepwater Horizon accident and the typically €200 million - €1 billion which a major commercial aircraft accident costs. Nuclear accidents are by most measures the most severe peacetime unsafe events. Social questions arise as to how, even whether, nuclear fission power technology can be rendered sufficiently safe; indeed what level of safety is sufficient, why, and how this is decided.

The key issues are thus not purely technical. Neither are they purely organisation-theoretical. The polity plays a role in deciding sufficient safety, at the extremes by giving up the technology, as in Germany and Switzerland, and at the other extreme through public protest, as has been experienced in Japan. At the technical level, the question arises why the clearest and most accessible public statement of the specific hazard which led to the Fukushima accident is to be found on a book by a sociologist of organisations, Charles Perrow, and not, say, in a publically-available Hazard Analysis by the operator or regulator of the accident plant. This phenomenon makes it crystal clear that sociology of engineering has a role to play in the very engineering of such systems.

Talks and References

Wednesday 3 August

Thursday 4 August