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, we have compiled the roadmap towards restoration from the
accident and then we updated the progress status of roadmap considering
the current situation, on July 19. Accomplishment of the Step1 target
"Radiation dose is in steady decline" has been confirmed. On October 17,
we updated the further progress. 
By bringing the reactors and spent fuel pools to a stable cooling
condition and mitigating the release of radioactive materials, we will
make every effort to enable evacuees to return to their homes and for all
citizens to be able to secure a sound life.

Below is the status of TEPCO's major facilities.

*The underlined parts are the updates from the previous press release.

[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)

 *At 2:30 pm on November 7, we suspended the alternative cooling in order
  to clear clogs in the primary strainer resulted from reverse cleaning,
  as a countermeasure against the alarm suction pressure decrease of
  alternative primary coolant system pump in spent fuel pool of Unit 3 at
  Fukushima Daiichi Nuclear Power Station (water temperature of spent fuel
  pool as of suspension: approx. 24.8°C). After finishing the reverse
  cleaning of the primary strainer, then, at 7:17 pm on the same day we
  restarted the alternative cooling (water temperature of spent fuel pool
  as of restart: approx. 22.5°C *It is supposed that water temperature as
  of restart became lower than that as of suspension because water in
  skimmer surge tank was cooled down by outside air.

 *At around 11:00 am on November 6, partner companies' workers who went on
  patrol found that the boiler of evaporative concentration apparatus
  stopped, and stopped operation of 3B and 3C of the apparatus. Since the
  operation panel on the site alerted "Very low water level in boiler
  supply water tank", we assumed that the boiler stopped due to this
  reason. After that, we investigated the cause on decrease of supply tank
  water level. When we tried to start a backup pump for transfer of boiler
  supply water, the alert stopped. Thus we judged that one pump was a bad
  condition. Although all the evaporative concentration apparatus stopped,
  water treatment by the water desalinations (RO membrane system) and
  water injection to the reactors have been continued. At 2:55 pm on
  November 7, we started another boiler by using a spare water transfer
  pump for boiler. Then, we started evaporative concentration apparatus 3B
  at 5:24 pm and 3C at 6 pm. Causes of the trouble of the water transfer
  pump for boiler are still under investigation.

 *At 2:24 am on November 8, we manually stopped the boiler of evaporative
  concentration apparatus in the water desalinations since alarm worked
  and indicated decrease of water level in boiler water supply tank at
  2:20 am. Then, we stopped evaporative concentration apparatus 3B at 2:28
  am ad 3C at 2:31 am. Although all the evaporative concentration
  apparatus stopped, water treatment by the water desalinations (RO 
  membrane system) and water injection to the reactors have been continued.
  Causes will be investigated in the future.

 *At 12:25 am on November 8, RO membrane unit of desalting facility in
  spent fuel pool, Unit 4 automatically stopped due to the alarm
  indicating leakage. Responding to the alarm, we confirmed that all the
  isolation valves of each unit were closed by the interlocks. Also,
  considering that all the spots at leakage risk were equipped with
  receiving pans which would be able to store all of the liquid in the
  unit, we judged that further deterioration of leakage or leakage to
  outside of the unit was unlikely. We will check the site and situation
  in the future. The operation of circulating cooling system has been
  continued.

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

· Kashiwazaki Kariwa Nuclear Power Station:
   Units 5, 6: under normal operation
   (Units 1 to 4 and 7: outage due to regular inspections)

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

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

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

[Impacts on Power Supply and Demand Balance]
This winter, there will be some minus factors such as the regular
inspection of Unit 5 at Kashiwazaki-Kariwa Nuclear Power Station. On the
other hand, there will be several plus factors such as the recovery of the
common thermal power stations which suffered the earthquake. As a result,
we expect to secure 54.9 GW (at the end of December), 54.6 GW (at the end
of January), 53.7 GW (at the end of February) supply power. 
Compared to the maximum demand in the last winter, which is 51.5 GW, we
will have 2.2 - 3.4 GW generation reserve margin.

We expect to maintain stable power supply this winter, however, as there
remains possibilities of unplanned shutdowns at our power stations and
growth in the demand according to the rapid change in the temperature, we
would like to ask your reasonable effort to save electricity. 

We will continue to make our efforts to maintain stable operation and
maintenance of the power facilities in order to "prevent in principle" the
planned blackouts and secure power supply.

Appendix: Past Progress (As of 9:00 am on November 8, 2011) (PDF 136KB)
Appendix: Past Progress (From March 11, 2011 to July 31, 2011) (PDF 225KB)

* Revised past progress