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 10:00 AM on May 29, we started transferring the accumulated water in Unit 6 Turbine Building basement to the temporary tank. At 4:00 PM on the same day, we stopped transferring. At 10:00 AM on May 30, we restarted transferring.
* With the current water injection amounts to Unit 1-3 (Unit 1: 6.5m3/h, Unit 2: 9.0m3/h, Unit 3: 7.0m3/h), it is predicted that the Unit 3 temperature will be slightly higher than that of Unit 1 and 2. As a result, the operational requirement margin specified by the technical specification will decrease for Unit 3. At 3:43 PM on May 29, the amount of water injection from the water supply system to Unit 1 reactor was changed from approx. 4.4m3/h to approx. 3.5m3/h. The water injection amount from the water supply system to Unit 3 reactor was also changed from approx. 1.9m3/h to approx. 2.9m3/h. The amounts of water injection from the reactor core spray system to Unit 1 and 3 remain the same (Unit 1: approx. 2.0m3/h, Unit 3: approx. 5.0m3/h).
* At 12:30 PM on May 29, data reading was failing on the Main Anti-Earthquake Building monitoring panel of the portable monitoring post at the west entrance. The same issue was occurring on the Main Anti-Earthquake Building monitoring panel of the wireless monitoring post used for alternative monitoring. The data from 12:30 PM to 7:30 PM was acquired by the alternative measurement done by a worker at the site. At 7:39 PM on the same day, the wireless monitoring system was recovered after resetting the equipment which transmits from the receiver to the terminal. As the data after 8:00 PM was acquired by the recovered wireless monitoring system, there is no data missing due to this issue.
[Fukushima Daini Nuclear Power Station]
· Unit 1 to 4: Shutdown due to the earthquake
Appendix:
Past Progress (As of 3:00 pm, on May 30, 2012) (PDF 333KB)
Appendix:
Past Progress (From March 11, 2011 to December 31, 2011) (PDF 460KB)
*
Revised past progress
