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Press Release (Jul 09,2011)
Plant Status of Fukushima Daiichi Nuclear Power Station (as of 3:00 pm, July 9)
  
*Updates are underlined time 
 
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. 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. 3.4m3/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. 
-From 8:56 am on June 30 to 2:49 pm on July 9, we transferred the 
 accumulated water from the basement of the turbine building of Unit 3 to 
 Centralized Radiation Waste Treatment Facility (Process Building). 
-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. 
-From 10:00 am to 5:00 pm on July 8, we transferred low radioactive 
 accumulated water from the outdoor temporary tank to Mega Float. 
-From 10:30 am to 4:30 pm on July 8, we transferred the accumulated water 
 from the turbine building of Unit 6 to temporary tank. 
-At 10:00 am on July 9, we started transferring low radioactive 
 accumulated water from the outdoor temporary tank to Mega Float. 
-At 10:30 am on July 9, we started transferring the accumulated water from  
 the turbine building of Unit 6 to temporary tank. 
-We will continue to take all measures to ensure the safety and to 
 continue monitoring the surrounding environment around the power station. 
  
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