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Press Release (Mar 26,2011)
Plant Status of Fukushima Daiichi Nuclear Power Station (as of 8:00 PM Mar 26th)
Plant Status of Fukushima Daiichi Nuclear Power Station (as of 8:00 PM Mar 26th)

*new items 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 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.
-At approximately 10:50 am on March 24th, white fog-like steam arising 
 from the roof part of the reactor building was observed.
-At approximately 11:30 am on March 24th, lights in the main control room
 was restored. 
-We had been injecting sea water into the reactor, but from 3:37 pm on 
 March 25th, we started injecting fresh water into it. 
Unit 2(Shut down) 
-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. 
-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 to nearly non-existent.
-We have been injecting sea water into the reactor, but from 10:10 am on 
 March 26th, we started injecting fresh water (with boric acid) into it.
-At approximately 4:46 pm on March 26nd, the light in the main control 
 room was turned on. 
Unit 3(Shut down) 
-Explosive sound and white smoke were confirmed at 11:01am March 4th. 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 
 measures 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 immediately implement measures and discharge air containing 
 radioactive material to outside. We will continue to monitor the status
 of the pressure of the reactor containment vessel.
-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.
-At around 4:20 pm on March 23rd, our staff confirmed light black smoke 
 belching from the Unit 3 building. At approximately 11:30 pm on March 
 23rd and 4:50 am on March 24th, our employee found no signs of smoke.
-We had been injecting sea water into the reactor pressure vessel, but 
 from 6:02 pm on March 25th, we started injecting fresh water into it. 
Unit 4 (outage due to regular inspection) 
-At approximately 6 am on March 15th, we 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 happened. 
Unit 5 (outage due to regular inspection) 
-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 2:30 pm, March 20th, the reactor achieved reactor cold shutdown. 
 At around 5:24 pm on March 23rd, when we switched the temporary Residual
 Heat Removal System Seawater Pump, it has stopped automatically. 
 At around 4:14 pm, March 24th we replaced the pump, and restarted 
 cooling of reactor at around 4:35 pm.
-At this moment, we do not consider any reactor coolant leakage inside
 the reactor containment vessel happened. 
Unit 6 (outage due to regular inspection) 
-Sufficient level of reactor coolant to ensure safety is maintained.
-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 7:27 pm, March 20th, the reactor achieved reactor cold shutdown.
-In relation to the two seawater side pumps of the Residual Heat Removal
 System, we switched the power source from temporary to permanent at 3:38
 PM and 3:42PM, Mar 25 respectively.
-At this moment, we do not consider any reactor coolant leakage inside 
 the reactor containment vessel happened. 
Today's work for cooling the spent fuel pools 
-We are considering further spraying 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.
-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. 
-4 workers were injured and transported to the hospital after explosive 
 sound and white smoke were confirmed around the Unit 1on 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 1:30 am on March 23rd, 1 worker who had been working on
 transporting a temporary power panel in the common pool was injured and 
 transported to Fukushima Daini Nuclear Power Station where the 
 industrial doctor is.
-On March 24th, it was confirmed that 3 workers from cooperative 
 companies who were in charge of cable laying work in the 1st floor and
 the underground floor of turbine building were exposed to the radiation
 dose of more than 170 mSv. 2 of them were confirmed that their skins on
 legs were contaminated. Although they were decontaminated, since there 
 was a possibility of beta ray burn injury, they were transferred to 
 Fukushima Medical University Hospital. The third worker was also 
 transferred to Fukushima Medical University Hospital on March 25th. 
 After that, the 3 workers were transferred to National Institute of 
 Radiological Sciences in Chiba Prefecture.
 Regarding this event, TEPCO has reported to the related government 
 ministries and agencies on measures to be taken to assure appropriate
 radiation dose control and radiation exposure related operations.
 Before today's restoration work, we will make notification to the 
 concerned parties and continue to take all possible measures to future
 management. 
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 is 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.
-At around 10:37 am March 21st, water spraying to common spent fuel pool
 and finished at 3:30 pm (conducted by TEPCO).
-At around 3:37 pm, March 24th, electricity supply to common spent fuel 
 pool has started from external power source. At around 6:05 pm, fuel 
 pool cooling pump was started to cool the pool.
 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 spraying to the spent
 fuel pools and water injection to the nuclear reactors by various
 regional fire departments* as well as Tokyo Fire Department. Also, 
 instruction regarding the setting and operation of large scale 
 decontamination system was provided by Niigata City Fire Headquarter and
 Hamamatsu City Fire Headquarter.
*: 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.
-By 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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