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The is a nuclear power plant located in the village of Higashidōri in northeastern Aomori Prefecture, on the Shimokita Peninsula, facing the Pacific Ocean. The plant has not generated electricity since Japan's 2011 nationwide nuclear shutdown in the aftermath of the Fukushima Daiichi nuclear disaster. It is unique in Japan in that it is two adjoining sites, one run by one company, the Tōhoku Electric Power Company and the other run by the Tokyo Electric Power Company. The reactors are all of Toshiba design. Construction of Tohoku Electric's Higashidori Unit-1 began in November 2000 and was completed in December 2005. The design was based on Tohoku Electric's Onagawa Nuclear Power Plant Unit-3, with improvements to the reactor vessel to allow for greater ease in inspection and maintenance. A separate building, apart from the containment structure, is dedicated specifically for the heat exchanger system based on seawater to provide primary coolant for the reactor. ==Earthquake susceptibility== On 20 December 2012 a panel of the Japanese Nuclear Regulatory Authority decided that two geologic faults under the nuclear plant were geological active: one fault called F-3 running vertically through the southern part of the plant's grounds close by the reactor no. 1 and another fault called F-9, that is running parallel with F-3 were probably active. Although Tohoku Electric Power claimed that the deformations inside the geological layers were the result of the swelling of clay minerals after they were exposed to water, Kunihiko Shimazaki, commissioner of the Nuclear Regulation Authority and head of the panel, said at the meeting, that any argument that the faults were not active, was totally unacceptable.〔The Mainichi Shimbun (20 December 2012) (Faults at another Japanese nuclear plant site likely active: panel )〕〔NHK-world (21 December 2012) (Team finds faults at nuclear plant possibly active )〕 In the application for permission to construct the No. 1 reactor at the Higashidori plant in 1996, Tohoku Electric Power Co. reported that there would be no active faults under the plant's premises. In another report submitted to the government in 2008 in response to the 2006 revision to the government's seismic-resistance design screening guidelines, the compagny asserted "There are no active faults in the neighborhood within 5 kilometers (from the Higashidori plant)." According to Shimazaki, chairman of the team of experts, the old sketches (of layers studied by Tohoku Electric) lacked credibility.〔The Mainichi Shimbun (21 December 2012) (NRA to examine method for fault impact forecast on nuke plants )〕 On 18 February 2012 the NRA-panel of experts presented their draft report on the earthquake fault complex at the premises of the nuclear reactor site. Their conclusions: * two faults, named "F-3" and "F-9," did produce several strike-slip thrusts within the past 110,000 years or so * the activity from the eight other F-type faults within the nuclear plant were "linked systematically." * an evaluation of the "F-1"-fault, that runs under the water-intake facility of the nuclear power plant was needed, because geological changes might have occurred in a period 120.000 to 130.000 years ago. These conclusions could cause an extra examination of the seismic resistance of the reactor buildings and re-enforcing them. On 14 February 2013 Tohoku Electric Power Co. made a request to the government to raise the electric power rates, while the company thought that the No. 1 reactor could be restarted around July 2015. At the presentation of the report, Tohoku Electric Power opposed these findings, and argued that water influx had caused the swelling of the geological layers, and it would start their own investigations the next day. The NRA-panel saw no grounds for this reasoning, they did not want to wait and planned to finalize the report with other experts.〔The Mainichi Shimbun (18 February 2013) (Panel deems quake faults at Higashidori nuclear plant active )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Higashidōri Nuclear Power Plant」の詳細全文を読む スポンサード リンク
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