Fukushima Daiichi nuclear disaster
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2006: The Japanese government opposes a court-order
In March 2006, the Japanese government opposed a court order to close a nuclear plant in the west part of the country over doubts about its ability to withstand an earthquake. Japan's Nuclear and Industrial Safety Agency believed it was "safe" and that "all safety analyses were appropriately conducted".[62]

[edit] 2007: Tsunami-study ignored
In 2007, TEPCO did set up a department to supervise all its nuclear facilities, and until June 2011 its chairman was Masao Yoshida, the chief of the Fukushima Daiichi power plant. An in-house study in 2008 pointed out that there was an immediate need to improve the protection of the power station from flooding by seawater. This study mentioned the possibility of tsunami-waves up to 10.2 meters. Officials of the department at the company's headquarters insisted that such a risk was unrealistic and did not take the prediction seriously.[63]

[edit] 2008: Seismic-concerns
In addition to concerns from within Japan, the International Atomic Energy Agency (IAEA) has also expressed concern about the ability of Japan's nuclear plants to withstand seismic activity. At a meeting of the G8's Nuclear Safety and Security Group, held in Tokyo in 2008, an IAEA expert warned that a strong earthquake with a magnitude above 7.0 could pose a "serious problem" for Japan's nuclear power stations.[64]

[edit] 2011: Results of governmental investigations
On request of the Japan Broadcasting Corporation, on 2 October 2011, the Japanese Government released a report of TEPCO to NISA. These papers proved that TEPCO was well aware of the possibility that the plant could be hit by a tsunami with waves far higher than the 5.7 meters which the plant was designed to withstand. Simulations done in 2008, based on the destruction caused by the 1896-earthquake in this area, made it clear that waves between 8.4 and 10.2 meters could overflow the plant. Three years later the report was sent to NISA, where it arrived on the 7 March 2011, just 4 days before the plant was hit by the tsunami. Further studies by scientists and an examination of the plant's tsunami resistance measures were not planned by TEPCO before April 2011, and no further actions were planned to deal with this subject before October 2012. TEPCO official Junichi Matsumoto said that the company did not feel the need to take prompt action on the estimates, which were still tentative calculations in the research stage. An official of NISA said that these results should have been made public by TEPCO, and that the firm should have taken measures right away.[65][66]

This all was in sharp contrast with the events at the Tōkai Nuclear Power Plant where the dike around the plant was raised to 6.1 meters after evaluations showed the possibility of tsunami-waves higher than previously expected. Although the dike was not completely finished at 11 March 2011, the plant was able to ride out the tsunami, even though the external power-sources in Tokai were lost also. With two (of three) functioning sea-water-pumps and the emergency diesel-generator the reactor could be kept safely in cold shutdown.[67]

On 26 November, a TEPCO spokesman mentioned that TEPCO would have been better prepared to cope with the tsunami in March 2011, if it had taken the 2008-study more seriously. TEPCO was also willing to use the estimates of renewed study done by a national civil engineering society for its facility management.[63]

Nuclear Safety Commission Chairman Haruki Madarame told a parliamentary inquiry in February 2012 that "Japan's atomic safety rules are inferior to global standards and left the country unprepared for the Fukushima nuclear disaster last March". There were flaws in, and lax enforcement of, the safety rules governing Japanese nuclear power companies, and this included insufficient protection against tsunamis.[68]