Onagawa Nuclear Power Plant

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Active reactors ( gross ):

The Onagawa nuclear power plant (Japanese女 川 原子 力 発 电 所, Onagawa genshiryoku hatsudensho ) is a nuclear power plant in Japan with boiling water reactors. It is in the area of ​​Onagawa and Ishinomaki Places in Miyagi Prefecture. The plant is 1.73 square kilometers and is one of the Tōhoku Denryoku. The power plant is located directly on the Pacific Ocean, on the Oshika Peninsula between the coastal hamlets of Tsukahama and Yoriiso, about 70 kilometers northeast of the city of Sendai. The system is cooled with sea water.

Onagawa -3 is one of the most modern blocks in Japan. He served as a prototype for the nuclear power plant Higashidori -1 of the Tōhoku Denryoku. Its construction was an attempt to regain lost confidence again. So there is a viewing gallery and an ISO 14001 certification also the heated cooling water is -. Least seven degrees warmer than before - initiated only ten meters below the surface again. This is to ensure better mixing and thus a smaller impact on the environment.

Were built the reactors from Toshiba.

Incidents

  • In July 1988, were pushed away by an error in the manual control rods instead. The incident was not reported. Since the manual has been used in several power plants, it was also there to incidents, without the fault has been corrected. This meant that it came on 18 June 1999 a 15-minute, uncontrolled chain reaction in a nuclear power plant Shika. Also, this incident was not reported and known until 2007.
  • At the turn of 1999/2000 was at 12:02 local time clock of the radioactivity monitoring for 10 minutes.
  • On 24 February 2000, a floor was burning in an adjacent building. The fire was extinguished after half an hour.
  • On February 4, 2002, two workers were slightly contaminated, as they damaged a spray can in inspection work. In the thus triggered fire they suffered burns.
  • In March 2007, the company had to admit that it had come as part of maintenance of Onagawa 1 to an emergency stop and the authorities were not informed.
  • On 11 March 2011 broke the nuclear power plant due to the heavy Tōhoku earthquake, whose epicenter was only 75 km from the power plant, a fire in a separate turbine building. The power plant was shut down. Since it is built on a 15 meter high artificial base, the tsunami taught here at comparatively little damage. However, the blocks like in Fukushima ran temporarily to emergency diesel generators; it fell in block 2, two of the diesel after a certain period of time, which after cooling had to be partly taken over by a self- steam - driven emergency cooling system; both diesel were after repair after a certain period of time available, so the reactor could be cooled down without damage (INES 2). The operator Tohoku Electric said the afternoon of March 13 ( local time) that an increase in radiation was found at 400 times the normal levels of radiation, possibly originated this radiation from the Fukushima nuclear power plant I; however, spoke against the prevailing wind direction. As provided for in Article 10 of the Act on Special Measures Concerning Nuclear Emergency Preparedness, the lowest emergency level of a nuclear emergency for the Onagawa nuclear power plant has been declared around midnight of March 13 (local time). These radiation levels reached up to 21 mSv per hour, which is why you had informed the government, after 10 minutes, the value fell to 10 mSv per hour.
  • An aftershock on 7 April 2011 led to the failure of the external power supply in the nuclear power plant emergency diesel took over the cooling. Here, in the first block spilled 3.8 liters of contaminated water from the fuel tank to the reactor hall, with an activity concentration of 5410 Bq / kg. The external power supply could be restored on April 10, the contaminated water has been removed.

Data of the reactor units

The Onagawa nuclear power plant has three blocks:

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