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 8:03 PM on June 4, overload trip at the secondary system circulating pump (A) was confirmed by the emergency alarm of the air-fin cooler panel at Unit 4 spent fuel pool alternative cooling system. As a result of site investigation, a burn mark was confirmed near the motor terminal housing, and we reported it to Tomioka fire department (Naraha branch station) at 9:27 PM. Later we accepted the judgment that it was not a fire. As for Unit 4 spent fuel pool alternative cooling system, the secondary system circulating pump (B) was started up at 8:27 PM on the same day, there was no significant change in the pool water temperature. There was no problem with the cooling condition.
At 10:30 AM on June 5, the secondary system circulating pump (B) at Unit 4 spent fuel pool alternative cooling system was temporarily suspended in order to confirm the condition. There is no problem with the pool water temperature control as the temperature increase rate is estimated to be approx. 0.3℃/h. The condition of the secondary system circulating pump (A) and (B) at Unit 1 spent fuel pool alternative cooling system which have a similar structure will be confirmed.

* At 10:00 AM on June 5, accumulated water was transferred from Unit 6 Turbine Building basement to the temporary tank.

* At 10:18 AM on June 5, hydrazine was injected to Unit 2 spent fuel pool utilizing the circulating cooling system. At 11:20 AM on the same day, injection was completed.

* On June 5, sampling was conducted at the charcoal filter and the particulate filter of Unit 2 PCV gas control system.

* June 5, dust sampling was conducted at the open part of Unit 2 Reactor Building (Blowout panel).

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


Appendix
Past Progress (As of 3:00 pm, on June 5, 2012) (PDF 414KB)
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We apologize for any inconvenience this may cause.

Appendix
Past Progress (From March 11, 2011 to December 31, 2011) (PDF 460KB)

* Revised past progress