*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. 3.6m3/h through reactor feed
  water system piping arrangement.
- We commenced injection of nitrogen gas into Primary Containment Vessel
  at 1:31am on 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 fresh water by a motor driven pump powered
  by the off-site transmission line. From 2:25pm on July 17, the motor
  driven pump of Unit 2 is injecting the freshwater to the Unit 1 and 2
  reactors.
- At 9:35 am on July 23, since the volume of injected water into the
  reactor was found to be decreased, we adjusted the volume up to 3.8m3/h.
  Hence, water is currently injected at approx. 3.8m3/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. 9.0m3/h through reactor feed
  water system piping arrangement.
- At 8:01 pm on July 14, injection of nitrogen gas into the Primary
  Containment Vessel started. 

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 2:45 pm on July 15, we started the operation of the original Residual
  Heat Removal System Pump (B).
- 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 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 June 17, 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.
- From 8:30 am on July 18 to 3:30 pm on July 22, we implemented
  installation work of a temporary roof for the Unit 3 turbine building in
  order to cover the roof's opening as a measure for rainwater.
- From 11 am on July 18 to 6 pm on July 22, accumulated water on the
  basement of Unit 6 turbine building was transferred to a temporary tank.
- On July 21, in order to conduct a restoration work for double circuit of
  Yonomori line which is power source for Unit 5 and Unit 6, we started
  a power switching work to stop the operation of Okuma Line No.3 which
  was connected to Yonomori Line No.1. At 12:26 pm on July 23, we
  finished switching power sources to receive power from Okuma Line No.3.
  According to this work, we stopped and started the facility as follows:
- Alternative cooling facility for the spent fuel pool cooling and
  filtering system of Uni3
  Stopped at 8:02 am and started at 2:52 pm on July 21. Stopped at 3:24 am
  and started at 11:45 am on July 23.
- Water treatment facility:
  Stopped at 8:38 am on July 21, started 12:28 am on July22, started water
  treatment of accumulated water at 12:40 am on July 22 and stopped at
  8:45 am on July 23
- Common pool:
  Stopped cooling at 8:40 am and started cooling at 2:41 pm on July 21.
  Stopped cooling at 3:46 am and started cooling at 9:41 am on July 23
- At 4:53 pm on July 22, we started transferring accumulated water at Unit
  3 turbine building vertical shaft to the Centralized Radiation Waste
  Treatment Facility (Process Main Building).
- At 4:56 pm on July 22, we started transferring accumulated water at Unit
  2 turbine building vertical shaft to the Centralized Radiation Waste
  Treatment Facility (Process Main Building).
- At 11 am on July 23, we started transferring accumulated water from the 
  turbine building of Unit 6 to the temporary tank. 
- We will continue to take all measures to ensure the safety and to
  continue monitoring the surrounding environment around the power station.