*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. 
- At 5:01 am on July 31, because the amount of water injection to the 
  reactor was found to be lowered, the water injection through Feed Water 
  System Piping Arrangement was adjusted to approx. 3.7 m3/h. 
  Water is currently injected at approx. 3.7 m3/h through 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. 
- At 5:01 am on July 31, because the amount of water injection to the 
  reactor was found to be lowered, the water injection thorough Feed Water 
  System Piping Arrangement was adjusted to approx. 3.7 m3/h. 
  Water is currently injected at approx. 3.7 m3/h through 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. 8.9m3/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 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 don't think there is any reactor coolant leakage 
  inside the primary containment vessel. 

Unit 5 (Outage due to regular inspection) 
- Sufficient level of reactor coolant to ensure safety is maintained.
- At 5 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 time, we don't think there is any reactor coolant leakage inside 
  the primary containment vessel. 

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 to cool down Spent Fuel Pool.
- At 7:27 pm on March 20, the reactor achieved cold shutdown. 
- At this time, we don't think there is any reactor coolant leakage inside 
  the primary containment vessel. 

Operation for cooling the Spent Fuel Pools 
- At 5:21 pm on May 31, we started cyclic cooling of Spent Fuel Pool of 
  Unit 2 by using alternative cooling system of the Pool's cooling and 
  filtering system.
- At 7:47 pm on June 30, we started cyclic cooling of Spent Fuel Pool of 
  Unit 3 by using alternative cooling system of the Pool's cooling and 
  filtering system.
- At 0:44 am on July 31, we started cyclic cooking of Spent Fuel Pool of 
  Unit 4 by using alternative cooling system of the Pool's cooling and 
  filtering system. 

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 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 8:00 pm on June 17, we started operation of Water Treatment Facility 
  against the accumulated water. 
- 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.
- At 11:04 am on July 30, we started transferring accumulated water at 
  spent fuel common pool building to the water desalinations tank. 
- At 4:10 pm on July 30, we started transferring accumulated water at Unit 
  2 turbine building to Centralized Radiation Waste Treatment Facility.
- At 4:13 pm on July 30, we started transferring accumulated water at Unit 
  3 turbine building to Centralized Radiation Waste Treatment Facility.
- Approximately 3:54 am on July 31, an earthquake whose seismic center was 
  off the coast of Fukushima prefecture with magnitude 6.4 occurred, though 
  there were no particular influence to the status of activities, including 
  water injection to the reactors of Unit 1 to 3, nitrogen gas injection to 
  Primary Containment Vessels of Unit 1 to 3, operation of water treatment 
  facilities, circulating cooling of pool water using alternative cooling 
  facilities of spent fuel pool cooling and filtering system of Unit 2 and 
  3. In addition, each unit's major parameters do not show unusual figures, 
  and no injured was found. The monitoring posts located on the border of 
  the power station's premise shows figures within its normal range.
- At 10:00 am on July 31, we started transferring low level accumulated 
  water at temporary tank to Mega Float.
- At 10:50 am on July 31, a leakage was detected at a water transfer pipe 
  (hose) of the desalination system. At 11:15 am, we stopped operation of 
  the transfer, and then shut down the desalination system. Since we found 
  no more leakage by replacing the said pipe, we resumed operation of the 
  system at 3:02 pm. 
- At 11:00 am on July 31, we started transfer of the accumulated water from 
  T/B, Unit 6 to Temporary Tank.