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Press Release (Mar 25,2011)
Plant Status of Fukushima Daiichi Nuclear Power Station (as of 10:00 PM Mar 24th)
*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.
- 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 have been injecting sea water into the reactor pressure vessel. 
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 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.
- 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 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.
  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 started replaced pump
  and at around 4:35 pm, cooling of reactor has restarted. 
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. 
Today's work for cooling the spent fuel pools 
- At approximately 5:35 am, we started injecting seawater into the fuel
  spent pool of Unit 3, using Fuel Pool Cooling and Filtering(clean up)
  system (FPC) and finished at 4:05 pm.
- At around 2:35 pm, spraying to unit 4 by concrete pump track and
  finished at around 5:30 pm.
- 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
  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 leg skin
  were contaminated. Although they were decontaminated, since it is 
  judged that there is possibility of beta ray burn injury, they were 
  transferred to Fukushima Medical University Hospital. After medical 
  examination at Fukushima Medical University Hospital, they will be 
  transferred to National Institute of Radiological Sciences in Chiba 
  Prefecture today (March 25) and stay for around four days to survey 
  the situation. Inspection result of the water that the workers stepped 
  in will be announced when it is reported. 
 
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.
- 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.
- 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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