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.
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
-At 9:47 AM on November 21, Unit 6 spent fuel pool cooling system was stopped for repairing the strainer changeover valve of the component seawater system (the pool water temperature when the system was stopped: 18.8°C). An alternating operation between the shutdown cooling system (for cooling the reactor) and the emergency heat load operation (for cooling the spent fuel pool) of the residual heat removal system was started. At 2:49 PM on November 24, the emergency heat load operation of the residual heat removal system was stopped (the pool water temperature when it was started: 16.0°C) and the shutdown cooling system was started at 3:12 PM on the same day (the reactor water temperature when it was stopped: 40.4°C).
-At 10:14 AM on November 25, we started transferring the accumulated water in Unit 2 Turbine Building basement to Unit 3 Turbine Building basement.
-At 1:54 PM on November 25, Unit 1 spent fuel pool alternative cooling system was stopped in prior to the common power supply modification which will suspend the power supply to the system from November 27 to 28 (the pool water temperature when the system was stopped: 16.0°C). The cooling will be suspended until November 28 and the pool water temperature increase rate is estimated to be approx. 0.088°C/h. There is no problem with the spent fuel pool water temperature control considering the sufficient margin to the maximum allowed temperature (65°C).
-At 10:15 AM on November 24, we started transferring the accumulated water from Unit 1 Turbine Building basement to Unit 2 Turbine Building basement. At 2:16 PM on November 25, the transfer was stopped.
-At 2:33 PM on November 25, the reactor injection water amount at Unit 1 was adjusted as follows since the amount had decreased. Feed water system: Increased from approx. 2.2m3/h to approx. 2.5m3/h, Reactor core spray system: Increased from 1.9m3/h to 2.0m3/h.
[Fukushima Daini Nuclear Power Station]
・Unit 1 to 4: Shutdown due to the earthquake.
Appendix:
Past Progress (As of 3:00 pm, on November 25, 2012) (PDF 731KB)
Appendix:
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.
