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Press Release (Dec 07,2011)
Status of TEPCO's Facilities and its services after the Tohoku-Chihou-Taiheiyou-Oki Earthquake (as of 9:00 am, December 7)
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 November 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.

* Underlined are 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)

* On December 4, workers of partner companies found that there was puddle 
  water inside the barrier around the evaporative condensation apparatus. 
  Afterwards we stopped the apparatus, and workers made visual inspection 
  of the apparatus and confirmed the leakage have stopped. After conducting 
  investigation, we found a crack in the concrete barrier, and water 
  leaking from this crack to the gutter (surface dose rate of leaked water: 
  beta ray 110 mSv/h, gamma ray 1.8 mSv/h). We also found water leaking 
  from between the barrier and the base concrete. We are considering 
  measures to stop this leakage to outside of the barrier. We confirmed 
  that the leakage had stopped by piling up sandbags between the barrier 
  and base concrete, and in the gutter. We sent the leaked water remaining 
  in the barrier to the waste water RO supply tank with a water pump 
  (approx. 15 m3). 
  Since the gutter led to the generally used channel of the power plant, we 
  have taken sea water from the channel around the water desalinations 
  (evaporative concentration apparatus) and the south drain (drain for the 
  generally used channel) and have conducted a nuclide analysis, and we 
  judged that the leaked water has been discharged into the sea from the 
  exit of generally used channel. It was estimated that approx. 150 liter 
  out of leakage water has flew in the channel, and assumed that it has 
  been discharged into the sea through the generally used channel. As a 
  result, the whole amount of radioactivity was approx. 2.6 x 1010 Bq 
  (temporary). As the impact of the discharge water into the sea, in the 
  assumption that we eat fish and seaweeds around the discharge channel 
  every day, the effective zone for an adult is approx. 0.0037 mSv / year, 
  that equals to approx. 1/600 of annual dose from nature for general 
  public (2.4 mSv), so that we evaluate there is almost no impact .

* At 4:17 am on December. 7, on the alternative Spent Fuel Pool cooling 
  system of Unit 2, the alarm indicating that the difference of flow rates 
  between at the entering and at the exit of the primary pump is big went 
  off, and the system stopped automatically. At 4:41 on the same day, after 
  field investigation, no defect such as leakage was confirmed. Currently 
  the cause is under investigation,. At 4:00 am, the temperature of Spent 
  Fuel Pool was 18.4 degree C, the assumed increase of temperature is 0.3 
  degree C/h, from the viewpoint of Spent Fuel Pool temperature, there is 
  still enough allowance, so that there is no problem.

* We plan to establish the system injecting water into the reactor in Unit 
  1 to 3 using the condensate storage tank of Unit 3. In preparation of 
  such establishment, the stored water in the tank was transferred to the 
  basement of turbine building of Unit 3 from 10:22 am on November 21 to 
  9:45 am on November 24. As the calibration of water level gauge is 
  required if all the water is transferred, approx. 200 ton was left in the 
  tank. During the measurement of salt concentration in the left water, it 
  turned out that concentration was high. In order to secure the space for 
  additional water injection to decrease such concentration, at 10:00 am on 
  December 6, the left water was transferred from the tank to the basement 
  of the turbine building of Unit 3. At 8:54 am on December 7, we stopped 
  transferring.

· 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, December 7, 2011) (PDF 201KB)
Appendix: Past Progress (From March 11, 2011 to July 31, 2011) (PDF 225KB)

* Revised past progress

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