Timeline of the Fukushima nuclear accidents

Fukushima Dai-ichi (dai-ichi means "#1"), is a multi-reactor nuclear power site in the Fukushima Prefecture of Japan. The Fukushima Daiichi nuclear disaster occurred after a 9.0 magnitude Tōhoku earthquake and subsequent tsunami on 11 March 2011, only 14 days before the reactor was to be shut down. This offshore earthquake, near the island of Honshu, produced a large tsunami in Japan, and a tsunami warning for over 20 countries within and around the Pacific Rim.

The earthquake triggered a scram shut down of the three active reactors at the Fukushima I Nuclear Power Plant (Fukushima Dai-Ichi). The ensuing tsunami crippled the site, stopped the Fukushima I backup diesel generators, and caused a station blackout. The subsequent lack of cooling led to explosions and meltdowns at the Fukushima I facility, with problems at three of the six reactors and in one of the six spent-fuel pools.

Times are given in Japan Standard Time (JST), unless noted, which is UTC plus nine hours.

Tokyo Electric Power Company (TEPCO) submits a report to Japan's nuclear safety agency which predicts the possibility of a tsunami up to 10.2 metres high at the Fukushima Daiichi nuclear plant in the event of an earthquake similar to the magnitude 7.2 earthquake with accompanying tsunami that devastated the area in 1896. TEPCO actually made this prediction in 2008 but delayed in submitting the report because they "did not feel the need to take prompt action on the estimates".

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