*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.
- We commenced injection of nitrogen gas into Primary Containment Vessel
  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. 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. 
- 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 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 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 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.
- From 8:00 pm on June17, we started operation of water treatment of
  accumulated water at accumulated water treatment facility. 
- 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 8:56 am on June 30, we started transferring the accumulated water
  from the basement of the turbine building of Unit 3 to Centralized
  Radiation Waste Treatment Facility (Process Building).
- At 7:27 am on July 1, we stopped injecting treated water and started
  injecting only filtrate water, for the installation of the tank (buffer
  tank) for injection to the reactor. 
  At 2:22 pm on July 2, the installation work of the buffer tank was 
  completed. At 6:00 pm on the same day, 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 10:00 am on July 1, we started transferring of low radioactive stored
  water from outdoor temporary tank to Mega Float. 
- At 10:00 am on July 1, we started transferring of accumulated water from
  inside of turbine building of Unit 6 to temporary tank.
- At 6:55 am on July 3, in the outside temporary seawater cooling pumps (2 
  pumps) used for the cooling for the reactor of Unit 5, we found a 
  leakage of seawater from the water pipe (exit side) of one pump. To 
  change the leaking pipe, we stopped the pump at 10:00 am on the same day. 
  After that, we will stop the other pump as well. 
- We will continue to take all measures to ensure the safety and to
  continue monitoring the surrounding environment around the power station.