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Press Release (Feb 10,2012)
Status of TEPCO's Facilities and its services after the Tohoku-Chihou-Taiheiyou-Oki Earthquake (as of 11:00 am, February 10)
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) 
 
- Approximately on 9:40 am on February 8, the staff of a partner company 
  found the water in a temporary tank to the east of Unit 2 Turbine 
  Building overflowing. At that time we were pumping up the water in the 
  sub-drain to the temporary pool as a trial, thus on 10:15 am on the same 
  day we stopped the pump, and the overflow was stopped. Later we 
  investigated the site and confirmed that there was no water in trenches 
  nearby, therefore we concluded that the water didn't run into trenches 
  nor flow out into the sea. We also sampled the water in the tank. The 
  results of nuclide analyses were Cs-134: 3.4 x 10-1Bq/cm3, Cs-137: 5.2 x 
  10-1Bq/cm3. These results are the same as those of the water in the 
  sub-drain sampled today, therefore we concluded that the overflowed water 
  was the water in the sub-drain. The volume of the water overflowed from 
  the tank is evaluated as around 16 m3 at maximum.
- At 10:00 am on February 9, we started to transfer the water accumulated 
  in the basement of Unit 6 Turbine Building to temporary tanks. At 4:00 pm 
  on the same day, we stopped the transfer, and at10:00 am on February 10, 
  we resumed the transfer. 
- Since 9:50 am on February 10, we have conducted the work to add 
  flowmeters to the nitrogen injection line at the side of Primary 
  Containment Vessel of Unit 3 in order to improve the reliability of 
  nitrogen injection activity. During this period, due to this work, we 
  suspended the nitrogen injection task temporarily (*).  
  * 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 3 by conducting a planned shift beyond the 
    range of operational limitation (starting at 9:50 am on February 10). 
- From February 2, tendency of temperature rise at the bottom of PCV has 
  been observed. While we increased the water injection to the reactor and 
  have been monitoring the trend of the temperature, it is still high 
  around 70°C. On February 6, we sampled the gas by the gas control system 
  of Unit 2 Primary Containment Vessel. The density of Xenon 135 at the 
  entrance of the system was below the detection limit. Since it is below 
  1Bq/cm3, which is the threshold for judging re-criticality, we confirmed 
  the reactor didn't go re-critical, however, in order to avoid the 
  possibility of going re-critical being increased as a result of the water 
  density in the reactor being increased by rapid injection of cold water 
  is increased, we injected the boric acid into the reactor as a safety 
  countermeasure from 0:19 am to 3:20 am on February 7, which was before we 
  increased the volume of the water injection. At 4:24 am on the same day, 
  we changed the amount of the core spray system injection water from 
  3.7m3/h to 6.7m3/h (the amount of the continuing feed water system 
  injection is 6.8m3/h). Currently, the temperature is approx.66.7°C (as of 
  5 am on February 10). We will monitor the progress continuously.

- As finding of accumulated water containing radioactive materials at the 
  trench between the Process Main Building and the Miscellaneous Solid 
  Waste Volume Reduction Treatment Building [High Temperature Incinerator 
  Building] (December 18, 2011), we started the inspection of other 
  trenches at the site on January 11, 2012.
  As a result of the inspection made on February 9, the location where the 
  accumulated water was found and the preliminary results of the nuclide 
  analysis are as follows:
  · Inside the duct for telecommunication cables of Unit 5 & 6 
    I-131: below the detectible limit, Cs-134: below the detectible limit, 
    Cs-137:7.2x10-2 Bq/ cm3 
  · Inside the duct for emergency gas treatment piping    
    I-131: below the detectible limit, Cs-134:4.6x10-1 Bq/ cm3, 
    Cs-137:6.7x10-1 Bq/ cm3 
  · Inside the connection duct of Unit 5's chemical tank, inside the trench 
    for the piping of suppression pool water, inside the duct for common 
    suppression pool water surge pipe, inside the trench for fire- 
    extinguishing piping (at the west of Unit 5), inside the trench for 
    fire-extinguishing piping (at the west of Unit 6), and the inside the 
    trench of fire-extinguishing piping (at the south of Unit 5), we 
    confirmed no accumulated water. 
- At 8:39 on February 10, 2012, because it has been observed that the 
  amount of treatment flow of the second Cesium adsorption apparatus 
  gradually, we suspended temporarily the operation of the apparatus. 
- At 8:45 am on February 10, 2012, at the Centralized Radiation Waste 
  Treatment Facility, we started transferring accumulated water from On- 
  site Bunker Building to Process Main Building. 
- At 2:14 pm on February 7, 2012, we started transferring the accumulated 
  water from the basement of turbine building of Unit 2 to Centralized 
  Radiation Waste Treatment Facility (Miscellaneous Solid Waste Volume 
  Reduction Treatment Building [High Temperature Incinerator Building]). We 
  stopped the transfer at 8:21 am on February 10, 2012. 
- At 10:21 am on February 10, 2012, because the decrease of the volume of 
  injected water to the Unit 1's reactor, we adjusted the injected water 
  volume from Core Spray System from approx. 1.7 m3/h to approx. 2.0 m3/h 
  (we have kept the injected water volume from reactor feed water system at 
  approx. 4.5 m3/h). 
- At 10:05 am on February 10, 2012, because the decrease of the volume of 
  injected water to the Unit 3's reactor, we adjusted the injected water 
  volume from reactor feed water system from approx. 2.7 m3/h to approx. 
  3.0m3/h (we have kept the injected water volume from Core Spray System at 
  approx. 6.0 m3/h). 
- At approximately 6:30 pm on February 9, 2012, at Main Anti-Earthquake 
  Building, we confirmed that data monitoring using temporarily-installed 
  meters at Unit 1 was disabled. The measurement of plant parameters 
  including Containment Atmospheric Monitor, Containment vessel pressure, 
  Drywell HVH temperature, and the water level of the reactor was cancelled. 
  Later, because it is confirmed that a fuse of the equipment which supply 
  electricity to the temporarily-installed meters was blown at the central 
  control center of Unit 1 & 2 and that the power source for the meters wasv 
  out of order, at 6:15 am on February 10, we replaced the fuse, resulting 
  in that the plant parameters excluding Containment Vessel pressure and 
  the water level of the reactor and the others were turned to under 
  monitoring using Unit 1's temporarily-installed meters. Later, after 
  switching the power from the power source for meters whose fault wasv 
  found to the other power source for meters, all the plant parameters 
  turned to be monitored using the temporarily-installed meters of Unit 1 
  at 10:55 am on the same day. For reference, while data monitoring using 
  Unit 1's temporarily-installed meters was disabled, the key parameters in 
  terms of safety were continued to be monitored using web-cameras and 
  others inside the Main Anti-Earthquake Building. Because we confirmed 
  that there have been no significant fluctuation of the parameters, we 
  concluded that there is no problem in terms of safety. 
· 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 11:00 am, February 10, 2012) (PDF 419KB) 
Appendix: Past Progress (From March 11, 2011 to July 31, 2011) (PDF 225KB) 
 
* Revised past progress 
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