*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 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.
-As it was suspected that hydrogen gas had been accumulated inside Primary
 Containment Vessel, in order to prevent increase in density of oxygen, we
 commenced the valve opening operation concerning injection of nitrogen gas
 into the primary containment vessel at 10:30 pm on April 6 and commenced
 injection 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
 and are now injecting freshwater by a motor driven pump powered by the
 off-site transmission line. 
 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. 

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 4:35 pm on June 24, we started the cooling of the spent fuel pool by
 the pump of the Fuel Pool Cooling and Filtering System.
-From 3:00 pm to 5:18 pm on June 27, we injected boric acid solution to
 Spent Fuel Pool of Unit 3.
-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.
-At 4:20 pm on June 27, the operation of circulation injection cooling was
 initiated by injecting water from the filter water tank as well as usage
 of the treated water regarding water injection to the reactor. At 5:55 pm,
 since we confirmed a leakage from the pipe which supplies water from
 treated water tank to injection pump of reactor, we stopped supplying
 treated water. Injecting water to the reactor has been kept from filtered
 water tank at stated flow rate.Subsequently, we have implemented 
 measures against the leakage at pipe joint. At 2:36 pm on June 28, we 
 started operation of supply pump for treated water. 
-From 8:00 pm on June17, we started operation of water treatment of
 accumulated water at accumulated water treatment facility. 
-From 3:32 pm on June 21 to 9:58 am on 9:58, we had transferred
 accumulated water in turbine building of Unit 3 to central waste
 treatment facility building.
-At 9:56 am on June 22, we started transferring accumulated water in
 turbine building of Unit 2 to central waste treatment facility building.
-At 9:40 am on June 28, we started injecting fresh water to the reactor
 well (unit 4) and temporally dry separation pool for environment
 improvement (reduce radio active dose) on 5th floor reactor building of
 unit 4.
-At 12:00 pm on June 28, we found the water level gauge (manometer) of 
 temporary tank where accumulated water from turbine building in Unit 6 
 will be transferred lying on the floor. Since accumulated water was 
 leaking from the gauge, we stopped it by closing main valve. For safety, 
 we measured surface dose rate around and confirmed the result to be 
 equivalent to that of surrounding area. 
-We will continue to take all measures to ensure the safety and to
 continue monitoring the surrounding environment around the power station.