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. As the common supply modification was completed, the reactor water injection pump was switched from the injection pump in the Turbine Building to the regular reactor water injection pump on the hill during the period from 1:32 PM to 4:45 PM on November 30. In order to adjust the target injection water amount at Unit 1 reactor to the target injection water amount of the regular reactor water injection pump on the hill (total flow rate: 4.5m³/h), the amount was changed as follows. Feed water system: Increased from approx. 2.4m³/h to approx. 2.5m³/h, reactor core spray system: Decreased from approx. 2.5m³/h to approx. 2.0m³/h. Unit 2 and 3 reactor injection water amounts were also changed as follows.
[Unit 2] Feed water system: Increased from approx. 1.9m³/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: Decreased from approx. 2.1m³/h to approx. 2.0m³/h, reactor core spray system: Maintained at approx. 4.0m³/h.

- At 11:07 AM on December 1, Units 1 and 2 reactor injection water amounts were adjusted as follows since the amounts had decreased.
[Unit 1] Feed water system: Increased from approx. 2.3m³/h to approx. 2.5m³/h, Reactor core spray system: Increased from approx. 1.8m³/h to approx. 2.0m³/h.
[Unit 2] Feed water system: Increased from approx. 1.9m³/h to approx. 2.0m³/h, Reactor core spray system: Increased from approx. 3.7m³/h to approx. 4.0m³/h.

- 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 12:50 PM on December 1, the transfer was stopped.

- 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 (the pool water temperature when the system was stopped: 16.0℃). Upon checking the spent fuel pool alternative cooling system in prior to restart after the power supply to the system was recovered on November 29, an alarm indicating an abnormality with the heat exchanger secondary system radiation monitor had gone off and the radiation monitor reading had been downscaled. Since an abnormality was found with the radiation indicator as a result of inspecting the radiation monitor on November 30, the indicator was decided to be replaced on December 1. At 6:22 PM on November 30, the spent fuel pool alternative cooling system was started. Though the spent fuel pool water temperature increased from 16.0℃ (when cooling was stopped) to 21.5℃, there is no problem with its temperature control considering the sufficient margin to the maximum allowed temperature (65℃). After the radiation indicator was replaced and recovered, monitoring utilizing the radiation monitor was restarted at 1:00 PM on December 1.

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

Appendix: Past Progress (As of 3:00 pm, on December 1, 2012) (PDF 613KB)
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.