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

- From 1:25 PM to 6:45 PM on November 27, the reactor water injection pump was switched from the regular reactor water injection pump on the hill to the reactor water injection pump in the Turbine Building as the power supply to Units 1-3 regular reactor water injection pumps on the hill will be suspended during the common power supply modification scheduled on November 28 to 29. As the reactor injection water flow rate is difficult to adjust considering that the target injection water amount at Unit 1 (total flow rate: 4.5m³/h) is the same as the flow rate lower limit of the reactor water injection pump in the Turbine Building (4.5m³/h), Unit 1 reactor injection water amount was adjusted as follows to achieve the total reactor injection water amount of 5.0m³/h at 4:30 PM on the same day. Feed water system: Increased from approx. 2.4m³/h to approx. 2.5m³/h, Reactor core spray system: Increased from approx. 2.0m³/h to approx. 2.5m³/h. In addition, Unit 2 reactor injection water amount was adjusted as follows. Feed water system: Increased from approx. 1.8m³/h to approx. 2.1m³/h, Reactor core spray system: Maintained at approx. 4.0m³/h.

- At 12:12 AM on November 28, Units 1-3 reactor injection water amounts were adjusted as follows since the amounts had decreased.
[Unit 1] Feed water system: Increased from approx. 2.1m³/h to approx. 2.5m³/h, Reactor core spray system: Increased from approx. 2.4m³/h to approx. 2.5m³/h.
[Unit 2] Feed water system: Increased from approx. 1.6m³/h to approx. 2.0m³/h, Reactor core spray system: Increased from approx. 3.9m³/h to approx. 4.0m³/h.
[Unit 3] Feed water system: Increased from approx. 1.8m³/h to approx. 2.0m³/h, Reactor core spray system: Increased from approx. 3.9m³/h to approx. 4.0m³/h.

- 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℃). 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 3:01 PM on November 27, the emergency heat load operation was stopped (the pool water temperature when it was stopped: 17.0℃) and the shutdown cooling system was started (the reactor water temperature when it was started: 39.3℃) at 3:22 PM on the same day. At 12:07 PM on November 28, the spent fuel pool cooling system was started as the repair had been completed.

- 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 suspends the power supply to the system from November 27 to 28 (the pool water temperature when the system was stopped: 16.0℃). Though cooling was originally planned to be restarted on November 28, it has been postponed to November 29 due to the schedule change of the power supply suspension. Unit 1 spent fuel pool water temperature increase rate is approx. 0.088℃/h and the temperature is estimated to be approx. 21.5℃ as of 5:00 AM on November 28. There is no problem with the spent fuel pool water temperature control considering the sufficient margin to the maximum allowed temperature (65℃).

[Fukushima Daini Nuclear Power Station]
· Unit 1 to 4: Shutdown due to the earthquake.

- At 10:02 AM and 10:03 AM on November 28, Unit 1 emergency diesel generator (B) and the residual heat removal system (B) were put on non stand-by mode respectively to repair the temporary cable for the generator of Unit 1 emergency diesel generator cooling system cooling water pump (B). As the repair was completed, the emergency diesel generator (B) was put on stand-by mode at 11:45 AM on the same day and the residual heat removal system (B) was put in operation at 11:55 AM.

Appendix: Past Progress (As of 3:00 pm, on November 28, 2012) (PDF 739KB)
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.