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Press Release (Mar 23,2011)
Plant Status of Fukushima Daiichi Nuclear Power Station (as of 11:00 PM Mar 22nd)
*new items are underlined 
All 6 units of Fukushima Daiichi Nuclear Power Station have been shut down 
Unit 1 (Shut down) 
-Reactor has been shut down. However, the explosive sound and white smoke 
 were confirmed after the big quake occurred at 3:36 pm Mar 12th. It was 
 assumed to be hydrogen explosion.
-At approximately 2:30 am on March 23rd, seawater was started to be 
 injected to the nuclear reactor through the feed water system. 
-We have been injecting sea water into the reactor pressure vessel. 
Unit 2 (Shut down) 
-Reactor has been shut down and the level of reactor coolant had dropped 
 and the reactor pressure had increased because the Reactor Core Isolation 
 Cooling System stopped. Measures were taken to lower the pressure within 
 the Reactor Containment Vessel and to inject sea water into the Reactor 
 while carefully confirming safety. The level of reactor coolant and the 
 pressure of the Reactor resumed. 
-At approximately 6:00 am on March 15th, an abnormal noise began emanating 
 from nearby Pressure Suppression Chamber and the pressure within this 
 chamber decreased. 
-We completed receiving electricity from the external transmission line up 
 to the auxiliary transformer. We installed the power cable from the 
 transformer to the temporary power panel. At 3: 46 pm, March 20th, we 
 started energizing the load-side power panel.
-At 6:20 pm on March 21st, white smoke was confirmed arising from the top 
 of the reactor building. As of 7:11 am on March 22nd, smoke decreased to 
 the level where we can hardly confirm
-We have been injecting sea water into the reactor pressure vessel.
 
Unit 3 (Shut down) 
-Reactor has been shut down. However, the explosive sound and white smoke 
 were confirmed at 11:01am Mar 14th. It was assumed to be hydrogen 
 explosion.
-At 8:30am on March 16th, fog like steam was confirmed arising from the 
 reactor building.
-At approximately 6:15 am on March 17th the pressure of the Suppression 
 Chamber has temporarily increased. We were preparing to implement a 
 measurement to reduce the pressure of the reactor containment vessel 
 (partial discharge of air containing radioactive material to outside) in 
 order to fully secure safety. However, at present, it is not a situation 
 to take a measure immediately to discharge air containing radioactive 
 material to outside now. We will continue to monitor the status of the 
 pressure of the reactor containment vessel.
-We are working on receiving external power supply to Units 3 and 4.
-At approximately 4:00 pm, March 21st, light gray smoke was confirmed 
 arising from the floor roof of the Unit 3 building. On March 22nd, the 
 color of smoke changed to somewhat white and it is slowly dissipating.
-At approximately 10:45 pm on March 22nd, the light in the main control 
 room was turned on. 
-We have been injecting sea water into the reactor pressure vessel. 
Unit 4 (outage due to regular inspection) 
-Reactor has been shut down. However, at approximately 6 am on March 15th. 
 We have confirmed the explosive sound and the sustained damage around the 
 5th floor rooftop area of the Nuclear Reactor Building.
-On March 15th and 16th, we respectively confirmed the outbreak of fire at 
 the 4th floor of the northwestern part of the Nuclear Reactor Building. 
 We immediately reported this matter to the fire department and the 
 related authorities. TEPCO employees confirmed that each fire had already 
 died down by itself. 
-At this moment, we do not consider any reactor coolant leakage inside the 
 reactor containment vessel happened. 
Unit 5 (outage due to regular inspection) 
-Reactor has been shut down and the sufficient level of reactor coolant to 
 ensure safety is maintained.
-At 5 am, March 19th, we started the Residual Heat Removal System Pump (C) 
 in order to cool the spent fuel pool.
-At this moment, we do not consider any reactor coolant leakage inside the 
 reactor containment vessel happened.
-At 2:30 pm, March 20th, the reactor achieved reactor cold shutdown. 
Unit 6 (outage due to regular inspection) 
-Reactor has been shut down and the sufficient level of reactor coolant to 
 ensure safety is maintained.
-We are working on receiving external power supply to Units 5 and 6. We 
 completed the repair work on the emergency diesel generator (A).
-At 10:14 pm, March 19th, we started the Residual Heat Removal System Pump 
 (B) of Unit 6 in order to cool the spent fuel pool.
-At this moment, we do not consider any reactor coolant leakage inside the 
 reactor containment vessel happened.
-At 7:27 pm, March 20th, the reactor achieved reactor cold shutdown. 
Cooling of spent fuel pools 
-In Unit 3, water discharge by Self-Defense Force's helicopters was 
 conducted from 9:48 am in the morning on March 17th. Also water discharge 
 by the riot police's high-pressure water cannon trucks and Self-Defense 
 Force's fire engines was conducted from 7 pm on March 17th and finished 
 at 8:09 pm.
-In Unit 3, water discharge by Self-Defense Force's fire engines and US 
 army's fire engines was conducted from 2 pm and completed a quarter to 
 3 pm.
-After that, from 0:30 am, Mar 19th, water discharge by Tokyo Fire 
 Department's Hyper Rescue was conducted to Unit 3 and completed at 1:10 
 am. At around 2:10 pm, water discharge by Tokyo Fire Department's Hyper 
 Rescue to Unit 3 was conducted once again. At approximately 3:40 am, they 
 had finished water discharge.
-At approximately 8:21 am, March 20th, water discharge to Unit 4 by fire 
 engine has started with the cooperation of Self-Defense Forces and 
 finished at approximately 9:40 am. At approximately 6:45 pm, March 20th 
 water discharge to Unit 4 by Self-Defense's water cannon trucks was 
 conducted and finished at approximately 7:45 pm.
-From 3:05 pm to 5: 20 PM on March 20th, 40 tons of seawater was injected 
 into Unit 2 by TEPCO employees.
-From 9:30 pm on March 20th, water discharge by Tokyo Fire Department's 
 Hyper Rescue was conducted to Unit 3 and completed at approximately 4:00 
 am today.
-At approximately 6:30 am today,, water discharge to Unit 4 was started by 
 Self-Defense Force's fire engines and US army's fire engines and was 
 finished at approximately 8:40 am. 
-From around 4:00 pm to 5:00 pm on March 22nd, approximately 18 tons of 
 seawater was injected into Unit 2 by TEPCO employees.
-From around 3:10 pm on March 22nd, water was sprayed to Unit 3 by Tokyo 
 Fire Department's Fire Rescue Task Forces and Osaka City Fire Department 
 was conducted and completed at approximately 4:00 pm on the same day. 
 From around 5:20 pm on March 22nd, water was sprayed to Unit 4 using the 
 concrete pumping vehicle and it was finished at around 8:30 pm on the 
 same day.
-At approximately 10:00 am on March 23rd, we started spraying water to 
 Unit 4 using the concrete pumping vehicle. 
-We are considering further spraying at other units and others subject 
 to the conditions of spent fuel pools. 
Casualty 
-2 workers of cooperative firm were injured at the occurrence of the 
 earthquake, and were transported to the hospital on March 11th.
-4 workers were injured and transported to the hospital after explosive 
 sound and white smoke were confirmed around the Unit 1on March 11th.
-Presence of 2 TEPCO employees at the site is not confirmed on March 11th.
-1 TEPCO employee who was not able to stand by his own holding left chest 
 with his hand, was transported to the hospital by an ambulance on March 
 12th.
-1 subcontract worker at the key earthquake-proof building was unconscious 
 and transported to the hospital by an ambulance on March 12th.
-The radiation exposure of 1 TEPCO employee, who was working inside the 
 reactor building, exceeded 100mSv and he was transported to the hospital 
 on March 12th.
-2 TEPCO employees felt bad during their operation in the central control 
 rooms of Unit 1 and 2 while wearing full masks, and were transferred to 
 Fukushima Daini Nuclear Power Station for consultation with a medical 
 advisor on March 13th.
-11 workers were injured and transported to Fukushima Daini Nuclear Power 
 Station etc. after explosive sound and white smoke were confirmed around 
 the Unit 3. One of the workers was transported to the FUKUSHIMA Medical 
 University Hospital on March 14th.
-At approximately 10 pm on March 22nd, 1 worker who had been working on 
 setting up a temporary power panel in the common pool was injured and 
 transported to Fukushima Daini Nuclear Power Station where the industrial 
 doctor is. 
-At approximately 1 am on March 23rd, 1 worker who had been working on 
 setting up a temporary power panel in the common pool was injured and 
 transported to Fukushima Daini Nuclear Power Station where the industrial 
 doctor is. 
Others 
-We measured radioactive materials (iodine etc.) inside of the nuclear 
 power station area (outdoor) by monitoring car and confirmed that 
 radioactive materials level is getting higher than ordinary level. As 
 listed below, we have determined that specific incidents stipulated in 
 article 15, clause 1 of Act on Special Measures Concerning Nuclear 
 Emergency Preparedness (Abnormal increase in radiation dose measured at 
 site boundary) have occurred.
 ·Determined at 4:17 pm Mar 12th (Around Monitoring Post 4)
 ·Determined at 8:56 am Mar 13th (Around Monitoring Post 4)
 ·Determined at 2:15 pm Mar 13th (Around Monitoring Post 4)
 ·Determined at 3:50 am Mar 14th (Around Monitoring Post 6)
 ·Determined at 4:15 am Mar 14th (Around Monitoring Post 2)
 ·Determined at 9:27 am Mar 14th (Around Monitoring Post 3)
 ·Determined at 9:37 pm Mar 14th (Around main entrance)
 ·Determined at 6:51 am Mar 15th (Around main entrance)
 ·Determined at 8:11 am Mar 15th (Around main entrance)
 ·Determined at 4:17 pm Mar 15th (Around main entrance)
 ·Determined at 11:05 pm Mar 15th (Around main entrance)
 ·Determined at 8:58 am Mar 19th (Around MP5)
 From now on, if the measured figure fluctuates and goes above and below 
 500 micro Sv/h, we deem that as the continuous same event and will not 
 regard that as a new specific incidents stipulated in article 15, clause 
 1 of the Act on Special Measures Concerning Nuclear Emergency 
 Preparedness (Abnormal increase in radiation dose measured at site 
 boundary) has occurred. In the interim, if we measure a manifestly 
 abnormal figure and it is evident that the event is not the continuous 
 same event, we will determine and notify.

-The national government has instructed evacuation for those local 
 residents within 20km radius of the periphery and evacuation to inside 
 for those residents from 20km to 30km radius of the periphery, because 
 it's possible that radioactive materials are discharged.
-At approximately 10am on March 15th, we observed 400mSv/h at the inland 
 side of the Unit 3 reactor building and 100mSv/h at the inland side of 
 the Unit 4 reactor building.
-We checked the status of spent fuel in the common pool, and confirmed 
 that the water level secured. We are planning to conduct a detailed 
 inspection. 
-We found no signs of abnormal situation for the casks by visual 
 observation during the patrol activity. A detailed inspection is under 
 preparation.
-At Units 5 and 6, in order to prevent hydrogen gas from accumulating 
 within the buildings, we have made three holes on the roof of the 
 reactor building for each unit.
-In total 12 fire engines are lent for the water discharge to the spent 
 fuel pools and water injection to the nuclear reactors by various 
 regional fire departments* as well as Tokyo Fire Department.
 *: Koriyama Fire Department, Iwaki Fire Brigade Headquarters, Fire 
 Headquarters of Sukagawa District Wide Area Fire-fighting Association, 
 Yonezawa City Fire Headquarters, Utsunomiya City Fire Headquarters, Fire 
 Headquarters of Aizu-Wakamatsu wide area municipal association, Saitama 
 City Fire Bureau, and Niigata City Fire Bureau.
-On March 21st and 22nd, we detected cobalt, iodine and cesium from the 
 seawater around discharge canal of Units 1, 2, 3 and 4. 
-We detected iodine and cesium in the air collected at the site of 
 Fukushima Daiichi Nuclear Power Station on March 20th and 21st.
-Until March 22nd, Units 1 through 6 were started to be energized from the 
 external power source. 
-We will continue to take all measures to ensure the safety and to 
 continue monitoring the surrounding environment around the Power Station. 
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