Tokyo Elec. Power : (Jan 11,2012)Plant Status of Fukushima Daiichi Nuclear Power Station (as of 3:00 pm, January 11)

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	Press Release (Jan 11,2012) Plant Status of Fukushima Daiichi Nuclear Power Station (as of 3:00 pm, January 11) *The 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, 2011. It was assumed to be hydrogen explosion. - At 3:37 pm on March 25, 2011, 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 10:11 am on December 10, 2011, in addition to water injection from water feeding system, we started water injection from piping of core spray system to the reactor. Current water injection volume is approx. 4.6 m3/h from the reactor feed water system and approx. 1.7 m3/h from the core spray system. - At 1:31 am on April 7, 2011, we commenced injection of nitrogen gas into Primary Containment Vessel. - At 11:22 am on August 10, 2011, we started cyclic cooling for the water in the spent fuel pool by an alternative cooling equipment of the Fuel Pool Cooling and Filtering System. - On October 28, 2011, we completed installation of the cover for the Reactor Building in order to contain dispersion of radioactive substances. - At 4:04 pm on November 30, 2011, we started operation to inject nitrogen into the reactor pressure vessel. - At 6:00 pm on December 19, 2011, a full-scale operation of the PCV gas management system started. Unit 2 (Shut down) - At approximately 6:00 am on March 15, 2011, an abnormal noise began emanating from nearby Pressure Suppression Chamber and the pressure within the chamber decreased. - At 10:10 am on March 26, 2011, 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 2:59 pm on September 14, 2011, in addition to water injection from water feeding system, we started water injection from piping of core spray system to the reactor. Current water injection volume is approx. 2.9 m3/h from the reactor feed water system and approx. 7.1 m3/h from the core spray system. - At 5:21 pm on May 31, 2011, we started cyclic cooling for the water in the spent fuel pool by an alternative cooling equipment of the Fuel Pool Cooling and Filtering System. (We also injected hydrazine (corrosion inhibitor) from 1:38 pm to 3:43 pm on January 10 2012.) - At 8:06 pm on June 28, 2011, we started injecting nitrogen gas into the Primary Containment Vessel. - At 6:00 pm on October 28, 2011, a full-scale operation of the PCV gas management system started. - At 10:10 am on January 11, due to the preparation of inspection of the Primary Containment Vessel(PCV) of Unit 2, we adjusted the amount of nitrogen injected to the PCV from 13 Nm3/h to 10 Nm3/h to reduce the pressure of the inside. The amount of emission from the PCV gas management system was not changed.Unit 3 (Shut down) - Explosive sound and white smoke were confirmed at approximately 11:01 am on March 14, 2011. It was assumed to be hydrogen explosion. - At 6:02 pm on March 25, 2011, 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. - At 2:58 pm on September 1, 2011, we started water injection by core spray system in addition to water injection by the reactor feed water system piping arrangement. - At 10:18 am on January 11, because of the replacement work of the water injection piping arrangement from the water feed system in association with the commissioning of reactor injection pump in Turbine Building of Unit 3, we have controlled the amount of injected water to the reactor gradually. The amount of injected water to the reactor of Unit 3 from the reactor feed water system was adjusted from approx. 1.9 m3/h to approx. 1.0 m3/h, and the amount from the core spray system was adjusted from approx. 7.0 m3/h to approx. 8.0 m3/h. Current water injection volume is approx 1.0 m3/h from the reactor feed water system and approx. 8.0 m3/h from the core spray system. - At 7:47 pm on June 30, 2011, we started cyclic cooling for the water in the spent fuel pool by an alternative cooling equipment of the Fuel Pool Cooling and Filtering System. - At 8:01 pm on July 14, 2011, injection of nitrogen gas into the Primary Containment Vessel started. - At 4:26 pm on November 30, 2011, we started operation to inject nitrogen into the reactor pressure vessel. Unit 4 (Outage due to regular inspection) - At around 6 am on March 15, 2011, we confirmed the explosive sound and the sustained damage around the 5th floor rooftop area of Reactor Building. - At 12:44 pm on July 31, 2011, we started cyclic cooling for the water in the spent fuel pool by an alternative cooling equipment of the Fuel Pool Cooling and Filtering System. - At 10:58 am on November 29, 2011, in order to decrease more salinity, we installed Ion exchange equipment and started the operation of such equipment. - 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 5:00 am on March 19, 2011, we started the Residual Heat Removal System Pump in order to cool the spent fuel pool. - At 2:45 pm on July 15, 2011, we started the operation of the original Residual Heat Removal System (System B) by its original seawater pump. - At 10:11 am on December 22, 2011, since we finished the recovery work of seawater pump (System B) of equipment water cooling system, we made a trial run. At 11:25 am on the same day, we confirmed no abnormalities and restarted the operation. - At this moment, we don't think there is any reactor coolant leakage inside the primary containment vessel. - At 2:39 pm on January 11, to protect the decline of facilities which are needed to maintain the stable cold shutdown and improve the high-humidity environment in the Reactor Building of Unit 5, we started up ventilation and air-conditioning system in the building. This air conditioning system inlet and outlet air by high-efficiency particle filter. Unit 6 (Outage due to regular inspection) - Sufficient level of reactor coolant to ensure safety is maintained. - At 10:14 pm on March 19, 2011, we started the Residual Heat Removal System Pump of Unit 6 to cool down Spent Fuel Pool. - At 2:33 pm on September 15, 2011, we started separately cooling the reactor through the Residual Heat Removal System and the spent fuel pool through Equipment Cooling Water System and Fuel Pool Cooling System. - At this moment, we do not think there is any reactor coolant leakage inside PCV. Injured and others - At 2:22 pm on January 9, 2012, at the Spent Sludge Storage Facility (*) which is under construction, a partner company's worker who had been engaged in concrete placement work reported his physical disorder. He was carried to the emergency medical room of Unit 5/6 and received medical treatment. Because he was in cardiopulmonary arrest, he was carried from Fukushima Daiichi Nuclear Power Station to Iwaki Kyouritsu Hospital at 3:25 pm. No radioactive materials were found to be attached to the worker's body. - At around 1 pm on January 11, we were reported from the partner company that his death was confirmed by a doctor at 5:02 pm on January 9. * Spent Sludge Storage Facility: The facility to store radioactive waste (spent sludge), which is produced during the process of accumulated water treatment, on a temporary basis. Others - At around 10 am on June 13, 2011, we started the operation of the circulating seawater purification facility installed at the screen area of Unit 2 and 3. - At 8 pm on June 17, 2011, 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 7:41 pm on August 19, 2011, we started treatment of accumulated water by parallel operation of one line from the cesium adsorption instrument to the decontamination instrument and the other treatment line of the cesium adsorption instrument No.2. - At 2:06 pm on October 7, 2011, we started to spray purified accumulated water brought from Unit 5 and 6 continually in order to prevent dust scattering and potential fire outbreaks from the cut down trees. - On October 28, 2011, we started installation of the water proof wall at the sea side, in front of the existing shore protection, Units 1-4, in order to contain marine pollution by underground water. - At 12:25 pm on December 13, 2011, we started the re-circulating operation of desalination facility (reverse osmosis membrane type) for the purpose of suppression of condensed water after desalination treatment. - From 8:17 am on January 10, 2012, we started to transfer accumulated water from the basement of the turbine building of Unit 2 to the Centralized Radiation Waste Treatment Facility, the Process Main Building. - At 9:47am on January 11 2012, we started to transfer accumulated water from the On-site Bunker Building of the Central Radiation Water Treatment Facility to the Process Main Building. - Because of the finding of accumulated water included radioactive materials at the trench between the Process Main Building and the Miscellaneous Solid Waste Volume Reduction Treatment Building[High Temperature Incinerator Building](December 18, 2011), we started the inspection of other trenches at the site on January 11.