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Press Release (Mar 20,2011)
Plant Status of Fukushima Daiichi Nuclear Power Station (as of 6:00 PM Mar 20th)
 
Press Release (Mar 20, 2011) 
Plant Status of Fukushima Daiichi Nuclear Power Station (as of 6:00 PM Mar 20th) 
 
*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 3:36PM Mar 12th.
  It was assumed to be hydrogen explosion.
- 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 6:00AM on March 15, 2011, 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. 
- 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 6:15AM 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.
- 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 6AM 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 19, 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.
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 7PM on March 17th
  and finished at 8:09PM.
- 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 2:10PM, 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.
- From 3: 05 PM to 5: 20 PM on March 20th, 40 tons of seawater was 
  injected into Unit 2 by TEPCO employees. 
- We are considering further water discharge at Unit 3 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.
- 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.
- 1 subcontract worker at the key earthquake-proof building was 
  unconscious and transported to the hospital by an ambulance.
- The radiation exposure of 1 TEPCO employee, who was working inside
  the reactor building, exceeded 100mSv and he was transported to
  the hospital.
- 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 Power Station for consultation with 
  a medical advisor.
- 4 workers were injured and transported to the hospital after explosive
  sound and white smoke were confirmed around the Unit 1.
- 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 at 10:56AM 
- Presence of 2 TEPCO employees at the site is not confirmed.
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
- 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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