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 around 8:00 AM on November 20, a TEPCO employee on patrol found a water leakage (of a size of a pencil) from the vent line^* of the second cesium absorption apparatus (SARRY) which goes outside of the Central Radioactive Waste Treatment Facility (Miscellaneous Solid Waste Volume Reduction Treatment Building [High Temperature Incinerator Building]). At around 8:26 AM on the same day, the second cesium absorption apparatus (SARRY) was stopped. The leaked water remains on the concrete ground outside. At 10:10 AM, the leakage from the vent line was confirmed to be stopped. The area affected by the leakage was approx. 16m x approx. 11m x approx. 1mm in depth, and the amount was approx. 176L. The radioactivity density analysis results of the leaked water are as follows.
Cesium 134: 3.7x10² Bq/cm³
Cesium 137: 6.5x10² Bq/cm³
Cobalt 60: 3.5x10⁰ Bq/cm³
Manganese 54: 1.9x10⁰ Bq/cm³
Radiation dose of the leaked water: approx. 1.8x10⁸ Bq
The leaked water is not considered to have flowed out to the sea since the leaked water remains on the concrete ground outside and there is no side ditch in the surrounding area. However, sandbags have been in.stalled in order to prevent the expansion of the leakage. The leaked water has been wiped off. The cause of the leakage will be investigated. There is no impact on the reactor water injection due to this incident as there is a sufficient amount of desalinated water. There has been no significant change in the monitoring post data and the plant condition due to this incident.
* Pipe which lets air inside the absorption towers of the second cesium absorption apparatus (SARRY) out of the High Temperature Incinerator Building.

- At 10:30 AM on November 20, the accumulated water transfer from Unit 3 Turbine Building basement to the Central Radioactive Waste Treatment Facility (Miscellaneous Solid Waste Volume Reduction Treatment Building [High Temperature Incinerator Building]) was stopped as the second cesium absorption apparatus (SARRY) was stopped due to a water leakage from its vent line. At 10:43 AM on the same day, the accumulated water transfer from Unit 4 Turbine Building basement to the Central Radioactive Waste Treatment Facility (Miscellaneous Solid Waste Volume Reduction Treatment Building [High Temperature Incinerator Building]) was stopped. At 11:13 AM on the same day, Skids 1 and 2 of the desalination system (reverse osmosis membrane) 3 were stopped.

- From 2:42 PM to 2:44 PM on November 11, Unit 5 residual heat removal system seawater pump in operation was switched from (C) to (A) since the flow rate of pump (C) had decreased. At 8:31 AM on November 20, the residual heat removal system (A) was stopped to have all the residual heat removal system seawater pumps temporarily suspended in order to inspect and repair the residual heat removal system seawater pump (C) (the reactor water temperature when the system was stopped: 31.7℃). At 12:09 PM on the same day, the residual heat removal system (A) was restarted (the reactor water temperature when the system was restarted: 33.8℃). There is no problem with the reactor water temperature control considering that there is a sufficient margin to the maximum allowed reactor water temperature of 100℃.

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

Appendix: Past Progress (As of 3:00 pm, on November 20, 2012) (PDF 727KB)
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.