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 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, 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.

*Updates since the previous press release 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)

*Since December 22, one of the atmospheric temperatures of Unit 1 Primary
 Containment Vessel (PCV) monitored by the Containment Atmospheric
 Monitoring System had risen (the atmospheric temperature of the PCV on
 December 22 was approx. 38°C, at 7 pm on December 27 was approx. 49°C).
 The other temperatures had not risen, so we conducted a survey from 9 am
 to 10 am on December 28, and we confirmed that there are no problems.
 From 11:00am to 12:15pm on the same date, to identify cause with
 monitoring, we adjusted the volume of Nitrogen injection, from approx.
 8 Nm3/h to approx.18 Nm3/h, and emission of the gas management system,
 from approx. 23 Nm3/h to approx.30 Nm3/h, as of before December 22. The
 temperature, the maximum went up to approx. 54.6°C at 6 pm on December 28,
 fell to approx. 52.3°C at 10 am and 1 pm on December 29.
 Other two temperature indicators were in gradual increases, but now the
 two are stable.
 The second: (Maximum) approx. 34.9°C at 9:00 pm on December 28 → approx.
 34.8°C at 1:00 pm on December 29.
 The third: (Maximum) approx. 39.2°C at 1:00 am on December 29 → approx.
 39.2°C at 1:00 pm on December 29.
 We are planning to identify cause with monitoring continuously.

*At 10:12 am on December 29, TEPCO staff observed a water leakage from the
 imperceptive leak in a hose around the concentrated water storage area of
 water desalinations (reverse osmosis membrane) while on patrol. We
 confirmed that filtrate water*, transferred with the hose from the
 filtrate tank to the boiler tank of the evaporative concentration
 apparatus, leaked from the water leakage. Just to be safe, we
 investigated nuclide analysis for the water, and the nuclide was bellow
 measurable limit. After that, we stopped transferring filtrate water, and
 filled the hole with tape, and the leaked water is now an average of a
 drop every two minutes. We are planning to replace the hose. The leaked
 filtrate water will not expand around there because there are no street
 gutters.

*filtrate water (freshwater): Water from Sakashita Dam

*At 10:23 am on December 29, due to the declining tendency of the suction
 pressure of the primary system circulating pump of the spent fuel pool
 alternative cooling system of Unit 3, we stopped the pump and then
 stopped cooling of the spent fuel pool temporarily to conduct flushing of
 the intake side strainer of the pump (water temperature at the stoppage:
 approx. 12.4°C). After that we conducted flushing and the suction
 pressure of the pump recovered, therefore at 0:09 pm on the same day, we
 restarted the pump and resumed cooling of the spent fuel pool (water
 temperature at resuming: approx. 12.5°C).

· 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 3:00 pm, December 29, 2011) (PDF 254KB)
Appendix: Past Progress (From March 11, 2011 to July 31, 2011) (PDF 225KB)

* Revised past progress