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
* On May 23, sampling was done at Unit 2 PCV gas control system. As a result, xenon 135 detected at the entrance of the system was below the detection limit (9.2x10-2Bq/cm3) and the re-criticality criteria (1Bq/cm3).
* At 2:59 PM on May 24, hydrazine injection into Unit 4 reactor well through the instrument pipes inside the reactor was started. At 4:34 PM on the same day, the injection was stopped.
* At 9:40 AM on May 25, the amount of water injection into Unit 2 reactor was adjusted as the water level decreased. The amount was increased as below.
From the supply water system: Approx. 2.6m3/h to 3.0m3/h
From the reactor core spray system: Approx. 5.9m3/h to 6.0m3/h.
* At 1:06 PM on May 25, hydrazine injection into Unit 2 spent fuel pool utilizing the circulating cooling system was started. At 2:25 PM on the same day, the injection was stopped.
[Fukushima Daini Nuclear Power Station]
· Unit 1 to 4: Shutdown due to the earthquake
* The transmission system of the monitoring posts (No. 1-7) located at the power station site boundary will be under inspection from May 21.
No. 6: 1:31 PM to 5:20 PM on May 21
No. 1: 9:11 AM to 11:30 AM on May 22
No. 2: 1:11 PM to 5:10 PM on May 22
No. 7: 9:11 AM to 11:10 AM on May 23
No. 3: 1:31 PM to 4:10 PM on May 23
No. 4: 9:11 AM to 11:30 AM on May 24
No. 5: From 1:31 PM to 3:50 PM on May 24
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Appendix:
Past Progress (As of 3:00 pm, on May 25, 2012) (PDF 323KB)
Appendix:
Past Progress (From March 11, 2011 to December 31, 2011) (PDF 460KB)
*
Revised past progress