Japan ministers ignored safety warnings over nuclear reactors

Robin McKie in the Guardian (UK): The timing of the near nuclear disaster at Fukushima Daiichi could not have been more appropriate. In only a few weeks the world will mark the 25th anniversary of the worst nuclear plant disaster ever to affect our planet – at Chernobyl in Ukraine.

…This weekend it is clear that the name Fukushima came perilously close to achieving a similar notoriety. However, the real embarrassment for the Japanese government is not so much the nature of the accident but the fact it was warned long ago about the risks it faced in building nuclear plants in areas of intense seismic activity. Several years ago, the seismologist Ishibashi Katsuhiko stated, specifically, that such an accident was highly likely to occur. Nuclear power plants in Japan have a "fundamental vulnerability" to major earthquakes, Katsuhiko said in 2007. The government, the power industry and the academic community had seriously underestimated the potential risks posed by major quakes.

…In the case of the incident at the Kushiwazaki reactor in northwestern Japan, a 6.8-scale earthquake on 16 July 2007 set off a fire that blazed for two hours and allowed radioactive water to leak from the plant. However, no action was taken in the wake of any of these incidents despite Katsuhiko's warning at the time that the nation's reactors had "fatal flaws" in their design.

…The trouble is, says Katsuhiko, that Japan began building up its atomic energy system 40 years ago, when seismic activity in the country was comparatively low. This affected the designs of plants which were not built to robust enough standards, the seismologist argues….

An aerial view of the Fukushima I nuclear power plant, pre-tsunami, Japan Ministry of Land, Infrastructure and Transport