Tomari Nuclear Power Plant

The Tomari Nuclear Power Plant (泊発電所, Tomari hatsudensho, Tomari NPP) is the only nuclear power plant in Hokkaidō, Japan. It is located in the town of Tomari in the Furuu District and managed by the Hokkaido Electric Power Company. All of the reactors are Mitsubishi designs. The plant site totals 1,350,000 m2 (334 acres), with an additional 70,000 m2 of reclaimed land.

Reactors on site

The annual load factors for both existing units are shown below.

This shows no loss in capacity for any year that is highly noticeable in the performance figures.


The plant was originally going to be located on an island and be named the Kyowa-Tomari NPP, but there was a change in plans and the location and name was changed.

  • In 2000, a worker fell into a sump tank in the chemical control system of the plant. The worker received a high radiation dose and died in the hospital later.
  • In September 2003, there was a leak in the steam generator causing about 140 liters of primary coolant to leak.
  • In May 2005, there was a trespassing event where someone crossed the fence into the property. Some people had apparently been gathering bamboo sticks as a part of a part time job and when discovered, 24 arrests were made. There were all questioned due to strong concerns about terrorism at the plant.
  • Also in 2005, company sensitive information was leaked from a worker's computer by a virus.
  • In July 2007, there were three separate fires related to the new unit that was under construction. Electrical wiring had apparently been cut and foul play was expected. Coming just days after a more serious earthquake caused events at the Kashiwazaki-Kariwa plant, it dealt a further blow to Japan's nuclear power industry.
  • On September 29, 2007, Kazutoshi Michinaka reported that there was no radiation leakage, and no one was hurt in the small fire at the half-built third reactor at Tomari Nuclear Power Plant, Hokkaidō, Japan At least 7 arson cases have been reported at the construction site this year.
  • Around March 2011 the No.3 reactor was stopped for checkups. Because of the aftermath of the Fukushima-disaster permission to restart was withhold by the Japanese industry ministry following local Hokkaido government criticism. In August the No.3 reactor had been the subject to trial runs for 5 months in a row. Normally the final phase of regular checkups by the NISA would take around a month before permission to resume commercial operations was granted. NISA reported the Nuclear Safety Commission on Thursday 11 August that no problems were found in the reactor during a 2-day final check, that ended on 10 August. According to NISA the reactor could safely be restarted. But the local government of Hokkaido did not give permission to restart, and the industry minister Banri Kaieda told Governor Harumi Takahashi that the prefecture's consent was vital, and that he would wait for their decision.
  • On August 17 2011, the Japanese Government approved the restart of reactor 3. This was the first nuclear reactor that got permission to be taken into service again after the events in Fukushima of March 11 2011.


2 photos

Building Activity

  • OpenBuildings
    OpenBuildings updated a digital reference
    about 6 years ago via Annotator
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