Due to the Tohoku-Chihou-Taiheiyou-Oki Earthquake which occurred on March 11, 2011, TEPCO's facilities including our nuclear power stations have been severely damaged. We deeply apologize for the anxiety and inconvenience caused.
Past Progress (As of 3:00 pm, on July 5, 2012) (PDF 443KB)
With regard to the accident at Fukushima Daiichi Nuclear Power Station, on April 17, 2011, we have compiled the roadmap towards restoration from the accident and on July 19 we accomplished the Step1 target "Radiation dose is in steady decline". Then on December 16 we confirmed the accomplishment of the Step 2 target "Release of radioactive materials is under control and radiation doses are being significantly held down".
In addition, on December 21, 2011, we have compiled the "Mid-to-long-Term Roadmap toward the Decommissioning of Fukushima Daiichi Nuclear Power Units 1-4, TEPCO".
In addition to the maintenance of the plant's stable condition, we will implement Mid-to-Long Term countermeasures towards the decommissioning of Fukushima Daiichi Nuclear Power Units 1-4 to enable evacuees to return to their homes as soon as possible and reduce the anxiety of the people in Fukushima and the whole nation as soon as possible.
Below is the status of TEPCO's nuclear power stations (Fukushima Daiichi and Fukushima Daini).
* The updates are underlined.
[Fukushima Daiichi Nuclear Power Station]
· Unit 1 to 4: Abolishment (April 19, 2012)
· Unit 5 to 6: Outage due to regular inspections before the earthquake
- As part of the ground improvement works for the installation of the cover for recovering fuel rods of unit 4, we checked the surroundings of the unit 4 emergency pit before removing it, and confirmed accumulated water (approx. 90m3) inside which apparently was either sea water or rain. For the removal of the pit the water must be transferred to another place, so at 10:10 am on June 22 we started transferring this water to unit 4 turbine building basement floor. At 1:00 pm on July 4 we completed this transfer.
- At 10:00 am on July 5, we started transferring accumulated water from unit 6 turbine building basement floor to a temporary tank.
- At 6:24 am on June 30, the alarm of the spent fuel pool substitution cooling system of unit 4 went off, showing that there was a system error, and the cooling system automatically stopped. After that we confirmed that there was no leakage at the site. During the investigation on the same day it was assumed that there was a problem in the UPS (Uninterruptible Power Supply) so we started bypassing works around the suspected UPS from 1:35 pm on July 1 and completed the bypass line at 2:45 pm on the same day. The cooling system was restarted at 3:07 pm. At 11:58 on July 5 we stopped the cooling system in order to remove the UPS and analyze the reason of malfunction. At 1:15 pm on the same day we restarted the cooling system (temperature of the pool at the time the cooling system stopped and the time it restarted was both 32°C).
- On July 5, we conducted dust sampling above Unit 3 nuclear reactor building.
[Fukushima Daini Nuclear Power Station]
· Unit 1 to 4 : Shutdown due to the earthquake.
Past Progress (From March 11, 2011 to December 31, 2011) (PDF 523KB)
* Revised past progress
The aforementioned attachments are only available in Japanese.
We apologize for any inconvenience this may cause.