*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 12. It was assumed to be hydrogen explosion.
-At approximately 2:30 am on March 23, seawater injection to the reactor
 through the feed water system was initiated.
-From 3:37 pm on March 25, we started injecting freshwater and are now
 injecting fresh water by a motor driven pump powered by the off-site
 transmission line.
-As it is suspected that hydrogen gas is accumulated inside Primary
 Containment Vessel, we commenced the valve opening operation concerning
 injection of nitrogen gas into the primary containment vessel at 10:30 pm
 April 6 and commenced injection at 1:31am April 7.
-At 11:50 am on May 17, we have decreased the amount of freshwater 
 injected into the reactor from approximately 10 m3/h to approximately 
 6 m3/h, since we have finished monitoring the trend shift of parameters 
 of the Reactor Pressure Vessel as well as the primary containment vessel, 
 the shift which would be resulted from the increase of the amount of 
 injected freshwater. 

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
 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 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.
-At 4:53 pm on May 12, as a part of work to switch the water injection
 line to the reactor from the fire extinction system to the reactor feed
 water system, we started water injection through the reactor feed water
 system in addition to through the fire extinction system. 
-At 10:11 am on May 17, we have increased the amount of water injection 
 through the reactor feed water system from approximately 6 m3/h to 
 approximately 9 m3/h 
-The current rate of water injection is approximately 9 m3/h through the
 fire extinction system piping arrangement and approximately 9 m3/h
 through the 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 happened. 

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 happened. 

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 happened. 

Operation for cooling the spent fuel pools 
-From 3:00 pm to 6:32 pm, on May 16, we sprayed water to Unit 3 by a
 temporary motor driven pump (from 3:10 pm to 5:30 pm, injected hydrazine
 [corrosion inhibitor] at the same time). 
-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 10:08 am on April 19, we started transfer of high level radioactive
 wastewater from the vertical shaft near the turbine building of Unit 2 to
 the Centralized Radiation Waste Treatment Facility.
-At 2:00 pm on May 1, we started transferring the accumulated water in
 turbine building of Unit 6 to temporary tanks.
-At 11:00 am on May 10, we started transferring the accumulated water
 inside the reactor building to the radiation waste treatment facility in
 Unit 6.
-We will continue to take all measures to ensure the safety and to
 continue monitoring the surrounding environment around the power station.