On March the 11th 2011, a tsunami struck the East coast of Japan. The Company operating the Fukushima Daiichi plant had been warned of the possibility of such an occurrence and was content that five-metre high sea walls would suffice to protect the plant.
A fifteen-metre high wave crashed over the nuclear plant, submerging all the diesel backup generators and damaging many buildings. The frantic battle to prevent catastrophic melt-down in the face of incomplete documentation and lack of planned procedures was now in the hands of a small number of extraordinarily brave men and women.
Seismologist: There was a tsunami last year. Magnitude 6.9. Water rose 0.2 metres.
TEPCO Official: That would hardly trouble Fukushima with seafront barriers to a height of 5.5 metres.
Seismologist: Yes, but there have been tsunamis of a completely different scale before. We think that the Jogan event of 869 AD is a more appropriate reference point.
TEPCO Official: Are you a seismologist or a historian?
Seismologist: We have created computer models of the devastation it caused.
TEPCO Official: Devastation? In 869 there would be a handful of villages and basic dwellings, which could be rebuilt in a week. I doubt there was very much damage, let alone devastation.
Seismologist: It destroyed a castle!
TEPCO Official: They are unverifiable legends.
Seismologist: But scientific surveys confirm historical accounts by analysing sediment left by the huge wave.
TEPCO Official: A wave able to overtop 5.5 metre sea defences?
TEPCO Official: We do not base design assumptions on folk-tales, we base them on computations by the Japan Society of Civil Engineers.