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. 
 
* 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 10:05 am on February 24, as the change in the injected water amount 
  was observed, the injected water amount was adjusted from approx. 1.6 
  m3/h to 2.0m3/h in the feed water system and from approx. 5.2m3/h to 5.0 
  m3/h in the core spray system. 
 
* At 8:21 am on February 24, as the gradual decline in the treated water 
  amount was observed in the second Cesium Adsorption Apparatus, its 
  operation was temporarily suspended to implement the washing of the 
  filter. At 10:30 am on the same day, the operation was restated and 
  designed water flow (approx. 36.0m3/h) was achieved at 10:32 am. 
 
* With regard to the water injection volume for Unit 2 reactor, which was 
  increased with temperature figure raising, we have gradually adjusted it 
  to the original volume before temperature increasing (Feed water system: 
  approx. 3.0m3/h, core spray system: approx. 6.0m3/h). During our 
  observing the plant parameter after decreasing the flow rate of feed 
  water system on February 22, we found that one thermometer in the lower 
  part of the RPV (top of the lower head 135°) indicated the different 
  movement from others. From 0:21 pm to 2:48 pm on February 23, we 
  investigated the concerned device. As the result of the measurement of 
  DC resistance, we found no breaking wire and availability of the 
  thermometer. But we confirmed that the DC resistance of it became higher 
  than the previous measurement test data. We will evaluate the soundness 
  of the concerned device and examine correspondence in future. We make 
  sure no re-criticality state because there were no significant changes 
  at the monitoring post and as the result of the sampling for the Gas 
  Control System of the Unit 2, we confirmed that the concentration of 
  Xe-135 was below the detectible limit. 
·   At 11:00 am on February 24, the temperature of the lower part of the 
    RPV (top of the lower head)(135°) : approx. 47.1 °C 
  (Reference) 
·   At 11:00 am on February 24, the temperature of the lower part of the 
    RPV (top of the lower head)(270°) : approx. 38.5 °C 
* At 6:00 am on February 24, in order to change the delivery valve of the 
  pump (A) of the reactor sea water system of Unit 5, we stopped the pump 
  (C) of the reactor sea water system. As a result, the cooling of the 
  spent fuel pool was stopped. (the temperature of the spent fuel pool at 
  the time : approx 17.4°C) At 12:08 pm on the same day, the system was 
  restarted after the completion of the work. Accordingly the cooling of 
  the spent fuel pool was restarted as well. (pool temperature at the time 
  of the cooling restart: approx 18.2°C) 
 
* At 9:40 am on February 24, we started the work to add the flow-meters to 
  the nitrogen injection line at the side of Primary Containment Vessel of 
  Unit 1 in order to improve the reliability of nitrogen injection 
  activity. Due to this work, we suspended the nitrogen injection task 
  temporarily (*). After the completion of the installation, we restarted 
  the nitrogen injection. At 1:10 pm, it was confirmed that there was no 
  significant variation in the parameters. 
* In the Chapter 12 of Nuclear Reactor Facilities Security Regulation "The 
  Way of Ensuring Mid-term Security", as the treatments like "Operational 
  limitation" or "Measures required in case of not satisfying the 
  operational limitation" are determined, it is supposed the operator act 
  per the required measures if it fails to satisfy the operational 
  limitation. This time, to implement maintenance works, we have suspended 
  the work of nitrogen injection at the side of Primary Containment Vessel 
  of Unit 1 by conducting a planned shift beyond the range of operational 
  limitation (from 9:40 am to 1:10 pm on February 24). 
 
·Fukushima Daini Nuclear Power Station: 
    Units 1 to 4: shutdown due to the earthquake 
 
·Kashiwazaki Kariwa Nuclear Power Station: 
    Units 6: under normal operation 
    (Units 1 to 5 and 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] 
This winter, there are some minus factors such as the regular inspection 
of Unit 5 at Kashiwazaki-Kariwa Nuclear Power Station. On the other hand, 
there are several plus factors such as the recovery of the common thermal 
power stations which suffered the earthquake. As a result, we expect to 
secure 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 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 on February 24, 2012) (PDF 711KB) 
Appendix: Past Progress (From March 11, 2011 to July 31, 2011) (PDF 225KB) 
 
* Revised past progress