*Updates 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 12th. It was assumed to be hydrogen 
 explosion.
-At approximately 2:30 am on March 23rd, seawater injection to the nuclear 
 reactor through the feed water system was initiated.
-From 3:37 pm on March 25th, we started injecting freshwater and are now 
 injecting fresh water by a motor driven pump powered by the off-site 
 transmission line.
-At 10:02 am on April 27th, in order to examine an appropriate amount of 
 water to make nuclear reactor flooded, the gradual operation to change 
 the amount of injecting freshwater from 6 m 3/h to approximately 14 m 3/h 
 was initiated
-As it is suspected that hydrogen gas is accumulated inside reactor 
 containment vessel, we commenced the valve opening operation concerning 
 injection of nitrogen gas into the reactor container vessel at 10:30 pm 
 April 6th and commenced injection at 1:31am April 7th. 

Unit 2(Shut down)  
-At approximately 6:00 am on March 15th, an abnormal noise began emanating 
 from nearby Pressure Suppression Chamber and the pressure within the 
 chamber decreased. 
-From 10:10 am on March 26th, we started injecting freshwater to the 
 reactor and are now injecting fresh water by a motor driven pump powered 
 by the off-site transmission line. 

Unit 3(Shut down)  
-Explosive sound and white smoke were confirmed at approximately 11:01am 
 on March 14th. It was assumed to be hydrogen explosion.
-From 6:02 pm on March 25th, 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. 

Unit 4(outage due to regular inspection)  
-At approximately 6:00 am on March 15th, we confirmed the explosive sound 
 and the sustained damage around the 5th floor rooftop area of the Nuclear 
 Reactor Building.
-At this moment, we do not consider any reactor coolant leakage inside the 
 reactor happened. 

Unit 5(outage due to regular inspection)  
-Sufficient level of reactor coolant to ensure safety is maintained.
-At 5:00 am on March 19th, we started the Residual Heat Removal System 
 Pump (C) in order to cool the spent fuel pool.
-At 2:30 pm on March 20th, the reactor achieved reactor cold shutdown. 
-At this moment, we do not consider any reactor coolant leakage inside the 
 reactor happened. 

Unit 6(outage due to regular inspection)  
-Sufficient level of reactor coolant to ensure safety is maintained.
-At 10:14 pm on March 19th, 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 20th, the reactor achieved reactor cold shutdown. 
-At this moment, we do not consider any reactor coolant leakage inside the 
 reactor happened. 

Operation for cooling the spent fuel pools  
-From 12:18 pm to 3:15 pm on April 27th, water spray to the spent fuel 
 pool of Unit 4 by the concrete pumping vehicle was conducted.
-From 10:15 am to 11:28 am on April 28th, water injected to the spent fuel 
 pool of Unit 2 by the temporary motor driven pump was conducted.  
-We will continuously conduct further water spray depending on the 
 conditions of spent fuel pools, if needed. 

Others  
-From 1:30 pm on April 26th, we started spraying dust inhibitor in order 
 to prevent diffusion of radioactive materials.
-At 10:08 am on April 19th we started transferring high level radioactive 
 wastewater to the Centralized Radiation Waste Treatment Facility.
-We will continue to take all measures to ensure the safety and to 
 continue monitoring the surrounding environment around the power station.