Press Release (Jan 26,2012) Plant Status of Fukushima Daiichi Nuclear Power Station (as of 10:00 am, January 26)

• 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. The Current water injection volume is approx. 4.4 m3/h from the reactor feed water system and approx. 2 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. - At 5:10 pm on January 25, regarding the reactor injection from the feed water system at the Unit 2, we changed the injection line from the pump located uphill to the T/B reactor injecting pump. - At 9:47 am on January 26, due to the change of injection duct owned by the pump located uphill, the volume from the feed water system increased from approx. 7.9m3/h to 8.7 m3/h, and the volume from the reactor core system decreased from approx. 1.0m3/h to 0m3/h. The current water injection amount from the reactor feed water system is approx. 8.7 m3/h and that from the core spray system is approx. 0 m3/h. - 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. - 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 10:46 am on December 1, 2011, we started the nitrogen injection to the Reactor Pressure Vessel. - At 11:50 am on January 19, 2012, we started the operation of the spent fuel pool desalting facility. - At 2:17 pm on January 24, 2012, at the desalting facility of the spent fuel pool of Unit 2, an emergency alarm of “RO unit warning” activated, and the system stopped automatically. We are currently checking for cause of the alarm. All of the separation valves of the system were closed by the inter-lock, and the alternative cooling system continues operation. Therefore, there is no influence on cooling, In addition, as a result of the on-site confirmation, no liquid leakage was confirmed. At 3:40 pm on January 25, 2011, we found there are no abnormalities by resuming the device. Since we could not detect the cause of the alarm warming although we think it resulted from the filter clogging, we will continuously monitor the progress.

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. The current water injection amount from the reactor feed water system is approx. 8.1 m3/h and that from the core spray system is approx. 1 m3/h. - 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. - At 3:18 pm on January 14, we started operation of the radioactive material removal instrument for the spent fuel pool in Unit 3

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 (from 1:30 pm to 3:14 pm on January 12, 2012, we injected hydrazine [corrosion inhibitor] in conjunction with the cyclic cooling). - 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.

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.

Others - At around 10:00 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 8:00 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. - As finding of accumulated water containing 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. - As a result of the inspection carried out on January 25, the nuclides analyzed at the locations where the accumulated water was discovered are as follows (advance report): - Inside of the connecting duct of Unit 1 Waste Liquid Surge Tank I-131: below measurable limit, Cs-134: approx. 1.2x101Bq/cm3, Cs-137: approx. 1.5x101Bq/cm3 - Inside of the main transformer cable duct I-131: below measurable limit, Cs-134 :approx. 1.5x100Bq/cm3, Cs-137 : approx.2.3x100Bq/cm3 - Inside of the fire extinguishing duct trench I-131: below measurable limit, Cs-134 : below measurable limit, Cs-137 : approx.1.0x10-1Bq/cm3 - From 9 :42 pm on January 25 to 8:13 am on January 26, we transferred the accumulated water from the basement of T/B, Unit 2 to the Centralized Waste Treatment Facility (Miscellaneous Solid Waste Volume Reduction Treatment Building [High Temperature Incinerator Building] and Process Main Building). - From 9 :53 pm on January 25 to 8:18 am on January 26, we transferred the accumulated water from the basement of T/B, Unit 3 to the Centralized Waste Treatment Facility (Miscellaneous Solid Waste Volume Reduction Treatment Building [High Temperature Incinerator Building] and Process Main Building). - On October 27, when a contracted company was conducting the annual checkup of a ceiling crane, which handles used fuel casks, a crack was found on the casing of the connection point of the vehicle for driving. After that, as we found that the damaged part was a crack that occurred at the gear coupling cover of the vehicle’s running drive, we completed a replacement of the part with a same kind. On January 25, 2012, we confirmed completion of the crane rehabilitation after we implemented a loading test and made sure there are no abnormalities.