search



Corporate Information

 
Press Release (Jul 14,2011)
Plant Status of Fukushima Daiichi Nuclear Power Station (as of 3:00 pm, July 14)
*Updates from previous press release are underlined. 
All 6 units of Fukushima Daiichi Nuclear Power Station have been shut down. 
Unit 1 (Shut down) 
- Explosive sound and white smoke were confirmed after the big quake 
  occurred at 3:36 pm on March 12. It was assumed to be hydrogen explosion.
- At approximately 2:30 am on March 23, seawater injection to the reactor 
  through the reactor feed water system was initiated.
- From 3:37 pm on March 25, we started injecting freshwater by a motor 
  driven pump which is now powered by the off-site transmission line. 
- At 5:30 am on July 14, we confirmed that the amount of water injected 
  into the reactor decreased, we adjusted the water injection at 3.5 m3/h 
  through reactor feed water system piping arrangement. Water is currently 
  injected at approx. 3.5m3/h through reactor feed water system piping 
  arrangement.
- We commenced injection of nitrogen gas into Primary Containment Vessel at
  1:31am April 7. 
Unit 2 (Shut down) 
- At approximately 6:00 am on March 15, an abnormal noise began emanating 
  from nearby Pressure Suppression Chamber and the pressure within the 
  chamber decreased. 
- From 10:10 am on March 26, we started injecting freshwater to the 
  reactor. At 6:27 pm on June 23, we changed the water injection line so 
  that we can inject water to Unit 1 and 2 by the motor driven pump for 
  Unit 1 and stopped the motor driven pump for Unit 2. 
  Water is currently injected at approx. 3.5m3/h through reactor feed water
  system piping arrangement. 
- At 8:06 pm on June 28, we started injecting nitrogen gas into the Primary
  Containment Vessel. 
Unit 3 (Shut down) 
- Explosive sound and white smoke were confirmed at approximately 11:01am 
  on March 14. It was assumed to be hydrogen explosion.
- From 6:02 pm on March 25, we started injecting fresh water to the reactor
  and are now injecting fresh water by a motor driven pump powered by the 
  off-site transmission line.
  Water is currently injected at approx. 9 m3/h through reactor feed water 
  system piping arrangement. 
Unit 4 (Outage due to regular inspection) 
- At approximately 6:00 am on March 15, we confirmed the explosive sound 
  and the sustained damage around the 5th floor rooftop area of Reactor 
  Building.
- At this moment, we do not consider any reactor coolant leakage inside the
  primary containment vessel has occurred. 
Unit 5 (Outage due to regular inspection) 
- Sufficient level of reactor coolant to ensure safety is maintained.
- At 5:00 am on March 19, we started the Residual Heat Removal System Pump 
  (C) in order to cool the spent fuel pool.
- At 2:30 pm on March 20, the reactor achieved cold shutdown.
- At this moment, we do not consider any reactor coolant leakage inside the
  primary containment vessel has occurred. 
Unit 6 (Outage due to regular inspection) 
- Sufficient level of reactor coolant to ensure safety is maintained.
- At 10:14 pm on March 19, we started the Residual Heat Removal System Pump
  (B) of Unit 6 in order to cool the spent fuel pool.
- At 7:27 pm on March 20, the reactor achieved cold shutdown. 
- At this moment, we do not consider any reactor coolant leakage inside the
  primary containment vessel has occurred. 
Operation for cooling the spent fuel pools 
- At 5:21 pm on May 31, we started cyclic cooling of the spent fuel pool in
  Unit 2 using alternative cooling system for fuel pool cooling and 
  filtering system. 
- At 7:47 pm on June 30, we started cyclic cooling of the spent fuel pool 
  in Unit 3 using alternative cooling system for fuel pool cooling and 
  filtering system.
- We will continuously conduct further water spray depending on the 
  conditions of spent fuel pools, if needed. 
Others 
- At 1:30 pm on April 26, we started spraying the dust inhibitor inside the
  site. 
- At 11:00 am on May 10, we started transferring accumulated water from the
  underground level of reactor building to the radiation waste treatment 
  facility of Unit 6.
- At approximately 10:00 am on June 13, we started the operation of the 
  circulating seawater purification facility installed at the screen area 
  of Unit 2 and 3.
- From 8:00 pm on June17, we started operation of water treatment of 
  accumulated water at accumulated water treatment facility. 
- At 6:00 pm on July 2, we started the circulating injection cooling to 
  inject the water, which was treated by the accumulated water treatment 
  system, to the reactors through the buffer tank.
- At 3:15 pm on July 10, we started transferring the accumulated water from
  the turbine building of Unit 3 to Centralized Radiation Waste Treatment 
  Facility Process Main Building.
- At 11:22 on July 12, in order to reduce radiation level on the 5th floor 
  of the reactor building of Unit 4, we started fresh water injection to 
  the reactor well and the pool to put equipment temporarily. However we 
  found water leakage from injection water line and stopped the injection 
  on 12:03 on the same day. As a result of survey, we found water leakage 
  from a connection part with water hose. Today, after changing the hose, 
  we started water injection at 11:50 am, but we found water leakage from 
  injection water line and stopped water injection at 12:45 am.
- From 10:00 am to 5:00 pm on July 13, we transferred low radioactive 
  accumulate water in the outside temporary tanks to the Mega Float. At 
  10:00 am on July 14, we started transferring low radioactive accumulate 
  water in the outside temporary tanks to Mega Float.
- At 10:09 am on July 13, we started transferring accumulated water from 
  the turbine building of Unit 2 to Centralized Radiation Waste Treatment 
  Facility Process Main Building.
- At 11:00 am on July 13, we stopped cesium adsorption instruments of the 
  accumulated water treatment facility for replacement of cesium adsorption
  tower. And then we started system flushing, but at 1:07 pm on July 13, we
  stopped flushing because we found leakage near connection part of the 
  chemical injection line of coagulation settling device of the facility. 
  At 12:07 pm on July 14, repairing of the leakage point was completed, and 
  we are planning to resume operation of the water treatment facility. 
  Meanwhile, we have been continuing water injection to the reactor.
- At approximately 1 pm on July 13, we found that the portable monitoring 
  post measuring dose rate at the main gate indicates zero. We checked the 
  equipment at the site and found no malfunction. Then we restarted the 
  equipment at the main anti-earthquake building and it indicates normal 
  value at approximately 2:55 pm. However, at around 10:00 pm on July 13, 
  we found that the portable monitoring post measuring dose rate indicates 
  zero, again. Then, the equipment did not work although we restarted the 
  equipment again. Therefore, we will repair or replace the instrument. 
- We will continue to take all measures to ensure the safety and to 
  continue monitoring the surrounding environment around the power station. 
back to page top


to TOP