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)
-At 10:08 am on April 6, we started transferring of accumulated water from the basement of Unit 2 T/B to Centralized Radiation Waste Treatment Facility (Process Main Building). At 9:21 am on April 9, we stopped transferring.
-At 9:55 am on April 9, changing the amount in water injection to the reactor of Unit 2 was confirmed and we adjusted water injection from the reactor feed water system from approx 2.8 m3/h to 3.0 m3/h, and water injection from the core spray system from approx. 6.5 m3/h to 6.0 m3/h.
-At 10:00 am on April 8, 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 9, we restarted transferring.
-At around 1:10 am, because the amount of flow which transfer condensed water from the water desalinator (reverse osmosis membrane) to the condensed water storage tank increased at around 1:05 am on April 5, 2012, we stopped the operation of the desalinator manually considering the possibility of water leakage. At around 1:45 am, In order to prevent water leakage, 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. At around 1:50 am, TEPCO's employee checked the site and found water leakage from the piping. At around 2:20 am, the employee confirmed that the leakage stopped since the desalinator was stopped its operation and the valve was closed. Because it was confirmed that water leaked from the lagging material of the pressure-proof hose, the employee 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, all gamma and beta nuclide was detected from the leaked water and water at ditch was below the detection limit. And on the same day we confirmed the all gamma and beta nuclide from re-sampling of the plant offshore was below the detection limit. On the same day, we conducted re-sampling the seawater around the exit of the ditch and we confirmed the result of all gamma was below the detection limit and the result of all beta was the same level of the detection limit. To keep watch on the trend, we conducted sampling of the seawater around the exit of the ditch on April 8. As the result, we confirmed the gamma nuclide was the same level of the detection limit and the all beta was below the level of the detection limit. In view of the reactor water condition (the water lever in the temporary storage tank of RO treated water for the water buffer tank to the reactor was decrease), at 9:50 am on April 8, we started the water desalinator (reverse osmosis membrane) to dispose of the water in waste liquid tank of RO. Before the operation, we exchanged the all polyethylene pipe which were set from the outlet of the pump for concentrated water to storage tank for RO concentrated water and we confirmed the no problem for the leakage. At 9:43 on the same day, we stopped the water desalinator (reverse osmosis membrane) after disposing the water in waste liquid tank of RO. Henceforth taking account with the water balance of the water desalinator system, we will operate it off and on.
・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 April.
Daily supply and demand balance is announced at our "TEPCO Electricity Forecast".
Appendix:
Past Progress (as of 3:00 pm,on April 9, 2012) (PDF 283KB)
Appendix:
Past Progress (Record from March 11, 2011 to December 31,2011) (PDF 460KB)
*
Revised past progress