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Press Release (Mar 12,2011)
Plant Status of Fukushima Daini Nuclear Power Station (as of 11pm March 12th)
[New Items are underlined]

Unit 1 (shut down at 2:48pm on March 11th)
- Reactor is shut down and reactor water level is stable.
- Offsite power is available.
- At 8:19am, there was an alarm indicating that one of the control rods
  was not properly inserted, however, at 10:43am the alarm was 
  spontaneously called off. Other control rods has been confirmed that they
  are fully inserted (reactor is in subcritical status)
- Status of main steam isolation valve: closed
- Injection of water into the reactor is done by Make-up Water Condensate
  System.
- At 6:08pm, we announced the increase in reactor containment vessel 
  pressure, assumed to be due to leakage of reactor coolant. However, we 
  do not believe there is leakage of reactor coolant in the containment
  vessel at this moment.
- At 5:22am, the temperature of the suppression chamber exceeded
  100 degrees. As the reactor pressure suppression function was lost, 
  at 5:22am, it was determined that a specific incident stipulated in 
  article 15, clause 1 has occurred.
- We decided to prepare implementing measures to reduce the pressure of
  the reactor containment vessel (partial discharge of air containing 
  radioactive materials) in order to fully secure safety. This preparation 
  work started at around 9:43am and finished at 6:00pm.

Unit 2 (shut down at 2:48pm on March 11th)
- Reactor is shut down and reactor water level is stable.
- Offsite power is available.
- Control rods are fully inserted (reactor is in subcritical status)
- Status of main steam isolation valve: closed
- Injection of water into the reactor is done by Make-up Water Condensate
  System.
- We do not believe there is leakage of reactor coolant in 
  the containment vessel.
- At 5:32am, the temperature of the suppression chamber exceeded 
  100 degrees. As the reactor pressure suppression function was lost,
  at 5:32am, it was determined that a specific incident stipulated in 
  article 15, clause 1 has occurred.
- We decided to prepare implementing measures to reduce the pressure of 
  the reactor containment vessel (partial discharge of air containing 
  radioactive materials) in order to fully secure safety. This preparation
  work started at around 10:33am and finished at 10:58pm.

Unit 3 (shut down at 2:48pm on March 11th)
- Reactor is shut down and reactor water level is stable.
- Offsite power is available.
- Control rods are fully inserted (reactor is in subcritical status)
- Status of main steam isolation valve: closed
- We do not believe there is leakage of reactor coolant in 
  the containment vessel.
- We decided to prepare implementing measures to reduce the pressure of 
  the reactor containment vessel (partial discharge of air containing radioactive
  materials) in order to fully secure safety. The preparation woke started at 
  around 12:08pm and finished at 12:13pm.
- Reactor cold shutdown at 12:15pm

Unit 4 (shut down at 2:48pm on March 11th)
- Reactor is shut down and reactor water level is stable.
- Offsite power is available.
- Control rods are fully inserted (reactor is in subcritical status)
- Status of main steam isolation valve: closed
- Injection of water into the reactor is done by Make-up Water Condensate
  System.
- We do not believe there is leakage of reactor coolant in 
  the containment vessel.
- In order to cool down the reactor, injection of water into the reactor
  had been done by the Reactor Core Isolation Cooling System, however, 
  At 6:07am, the temperature of the suppression chamber exceeded 
  100 degrees. As the reactor pressure suppression function was lost,
  at 6:07am, it was determined that a specific incident stipulated in 
  article 15, clause 1 has occurred.
- We decided to prepare implementing measures to reduce the pressure of 
  the reactor containment vessel (partial discharge of air containing 
  radioactive materials) in order to fully secure safety. The preparation
  woke started at around 11:44am and finished at around 11:52am.

Indication from monitoring posts installed at the site boundary did not
show any difference from ordinary level.
No radiation impact to the external environment has been confirmed.
We will continue to monitor in detail the possibility of radioactive
material being discharged from exhaust stack or discharge canal.
There is no missing person within the power station.
We are presently checking on the site situation of each plant while 
keeping the situation of aftershock and Tsunami in mind.
A seriously injured worker who had been trapped in the crane operating
console of the exhaust stack was transported to the ground at 5:13pm and
confirmed dead at 5:17pm. We sincerely pray for the repose of his soul.
A worker was lightly injured spraining his left ankle and cutting both
knees when he fell while walking at the site. The worker has returned to
work after medical treatment and rest. At 10:15pm, an earthquake occurred centered in offshore Fukushima
prefecture. No damage to the plant has been found at this moment. 
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