*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 nuclear 
 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. From on April 27, we have increased the amount of 
 injecting freshwater from approximately 6 m3/h to approximately 14 m3/h. 
 At 10:14 am on April 29, we put the amount of injecting freshwater back 
 to approximately 6 m3/h.
-As it is suspected that hydrogen gas is accumulated inside reactor 
 containment vessel, we commenced the valve opening operation concerning 
 injection of nitrogen gas into the reactor container vessel at 10:30 pm 
 April 6th and commenced injection at 1:31am April 7.
-At 10:01 am on May 6th, in order to make nuclear reactor flooded to the 
 top of Fuel range, we have increased the amount of injecting freshwater 
 from approximately 6 m3/h to approximately 8m3/h. 

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. 

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 the Nuclear 
 Reactor Building.
-At this moment, we do not consider any reactor coolant leakage inside the 
 reactor 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 reactor cold shutdown. 
-At this moment, we do not consider any reactor coolant leakage inside the 
 reactor 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 reactor cold shutdown. 
-At this moment, we do not consider any reactor coolant leakage inside the 
 reactor happened. 

Operation for cooling the spent fuel pools 
-On May 7th, we sprayed water to Unit 4 by the concrete pumping vehicle 
 from 2:05 pm to 5:30 pm.
-On May 8th, we injected water to Unit 3 by temporary motor-driven pump 
 from 12:10 pm to 2:10 pm. 
-We will continuously conduct further water spray depending on the 
 conditions of spent fuel pools, if needed. 

Others 
-The transfer of high level radioactive wastewater in Unit 2 to the 
 Centralized Radiation Waste Treatment Facility was temporarily suspended 
 at 9:22am on May 7th, due to construction of injection piping (reactor 
 feeding water system) to reactor of unit3. The construction work has 
 completed and we re-started the transfer at 4:02 pm.
-From March 27, transfer of accumulated water in Unit 5 turbine building 
 to a condenser has been conducted, and water with the amount of 
 approximately 600 m3 has been transferred from March 27 to May 2. 
 From May 2, we have started work relating to the set up of exhausters, 
 in order to improve the working environment inside the reactor building 
 of Unit 1. At 4:36 pm on May 5th, all of exhausters (6 units) were 
 started to operation. 
-We will continue to take all measures to ensure the safety and to 
 continue monitoring the surrounding environment around the power station.