*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.
