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 major facilities.

* The updates are underlined.

[Nuclear Power Station]
・Fukushima Daiichi Nuclear Power Station: Unit 1 to 3: shut down due to the earthquake:
(Units 4 to 6: outage due to regular inspections before the earthquake)

*On April 3, we sampled gas in gas management system at Primary Containment Vessel of Unit 2. As a result of analysis, we found Xe135 at the entrance of gas management system of Unit 2 was below detection limit (1.1×10^-1Bq/cm³) and it is below 1 Bq/cm³ that is the criteria of determination for recriticality.

*At 10:00 am on April 4, we started transferring the accumulated water from the basement of T/B of Unit 6 to the temporary tanks. At 4:00 pm on the same day, we stopped transferring. At 10:00 am on April 5 we resumed transferring.

*In the alternative cooling system for spent fuel pool of Unit 4, since we observed that the suction pressure of the circulating pump of the primary system tended to decrease, we temporarily stopped cooling the spent fuel pool by stopping the operation of the pump, in order to flash the suction strainer of the pump at 1:50 pm on April 4 (Water temperature in the pool at the time of stop of operation: approx. 26 ℃). After flashing, at 3:01 pm on the same day, we restarted the pump to resume cooling the spent fuel pool of Unit 4. We confirmed the recovery of suction pressure of the pump. (Water temperature in the pool at the time of restart of operation: approx. 26 ℃).

*Around 1:05 am on April 5, 2012: Because the amount of flow which transfer condensed water from the water desalinator (reverse osmosis membrane) to the condensed water storage tank increased, we stopped the operation of the desalinator manually at around 1:10 am considering the possibility of water leakage. In order to prevent water leakage, at around 1:45 am, we closed the valve located before and after the piping (pressure-proof hose) which transfer condensed water from the water desalinator to the condensed water storage tank. TEPCO's employer checked the site and found water leakage from the piping at around 1:50 am. Since the desalinator was stopped its operation and the valve was closed, the employer confirmed that the leakage stopped at around 2:20 am. Because it was confirmed that water leaked from the lagging material of the pressure-proof hose, the employer removed the material, confirming that the pressure-proof horse had been disconnected from the joint flange. Because there was possibility that condensed water amounting to approximately 12 m³ might have flown into sea via the ditch for general water discharge, we conducted sampling of the leaked water, water at the drainage ditch, and seawater around the exit of the ditch for general water discharge which locates around 300 m south from the water outlet of Unit 1 - 4. As a result, while gamma nuclide was detected from the leaked water and water at the ditch, the result was below the detection limit for the seawater around the exit of the ditch, we confirmed. Consequently, we plan to analyze the all beta-radioactivity of the sampled water. Although the operation of the water desalinator (reverse osmosis membrane type and evaporative concentration apparatus type) was suspended, there is no significant influence to the water injection into the reactor because there are affluent amount of water which has been already desalinated.

*At 1:05 am on April 5, the alert came from second cesium adsorption apparatus and it stopped automatically. We checked the device and found NO water leakage. We are now investigating the cause of the alert.

*At 1:20 pm on April 5, we started injection of hydrazine into reactor well of Unit4 through inside metering piping.

*On April 5, we conducted dust sampling above the reactor building of Unit 3 by the large crane

*At 10:08 am on April 3, we started the transfer of the accumulated water from the basement of Turbine Building of Unit 3 to the centralized radiation waste treatment facility (miscellaneous solid waste Volume reduction treatment building[high temperature incinerator building]). At 2:54 pm on April 5, we stopped transferring

・Fukushima Daini Nuclear Power Station:
Units 1 to 4: shutdown due to the earthquake

・Kashiwazaki Kariwa Nuclear Power Station:
Units 1 to 7: outage due to regular inspections

[Thermal Power Station]
・Power supply has returned to normal and the facilities damaged by the earthquake are now being handled in a timely manner.

[Hydro Power Station]
・Power supply has returned to normal and the facilities damaged by the earthquake are now being handled in a timely manner.

[Impacts on Transmission Facilities]
・Power supply has returned to normal and the facilities damaged by the earthquake are now being handled in a timely manner.

[Impacts on Power Supply and Demand Balance]
We expect to maintain stable power supply in March.
Daily supply and demand balance is announced at our "TEPCO Electricity Forecast".

Appendix: Past Progress (As of 3:00 pm, on April 5, 2012) (PDF 522KB)
Appendix: Past Progress (From March 11, 2011 to July 31, 2011) (PDF 225KB)
* Revised past progress