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 October 12, we started transferring the accumulated water in Unit 6 Turbine Building basement to the temporary tank. At 3:00 PM on the same day, the transfer was stopped.
- From August 20, 2011, the desalination system started operating to prevent corrosion of structural materials of Unit 4 spent fuel pool. However, the chloride concentration increased again due to reactor well water intrusion. The desalination system (mobile RO system) has been in operation for the purpose of desalting the spent fuel pool water since April 27, 2012 (desalination has been done utilizing the ion exchanger since September 10, 2012). Considering that the chloride concentration had been significantly reduced from approx. 1,944ppm (when the system started operating) to approx. 9ppm (the chloride concentration of the reactor well: approx. 10ppm), the desalination of Unit 4 spent fuel pool has been completed on October 12.
[ Fukushima Daini Nuclear Power Station ]
・Unit 1 to 4: Shutdown due to the earthquake.
- At 12:59 PM on August 30, 2011, the electric motor of the high-pressure reactor core spray component cooling seawater system pump was stopped while the high-pressure reactor core spray component cooling system and the high-pressure reactor core spray component cooling seawater system were in operation to adjust the water quality of Unit 2 high-pressure reactor core spray component cooling system. Upon investigation, faulty insulation resistance of the electric motor was found. The failed electric motor has been replaced with a newly manufactured one. On October 11, 2012, it was confirmed that the new electric motor is properly functioning as a result of trial operation.
- At 2:28 PM on October 12, the residual heat removal system at Unit 2 was switched from (A) to (B) for preparation of a disassembly inspection of the residual heat removal system (A).
Past Progress (As of 3:00 pm, on October 12, 2012) (PDF 555KB)
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.