Due to the Tohoku-Taiheiyou-Oki Earthquake which occurred on March 11th
2011, TEPCO's facilities including our nuclear power stations have been
severely damaged. We deeply apologize for the anxiety and inconvenience
caused.
Below is the status of TEPCO's major facilities.
*new items are underlined
[Nuclear Power Station]
Fukushima Daiichi Nuclear Power Station:
Units 1 to 3: shutdown due to the earthquake
(Units 4 to 6: outage due to regular inspections)
*The national government has instructed the public to evacuate for those
local residents within 20km radius of the site periphery and to evacuate
voluntarily for those local residents between 20km and 30km radius of the
site periphery.
*Off-site power has been connected to Unit 1 to 6 by March 22, 2011.
*Unit 1
-The explosive sound and white smoke was confirmed near Unit 1 when the
big quake occurred at 3:36pm, March 12th.
-We started injection of sea water at 8:20 pm, March 12th, and then boric
acid which absorbs neutron into the reactor afterwards.
-At approximately 2:30 am, March 23rd, we started the injection of sea
water into the reactor from feed water system. After that, the injection
of freshwater was started from 3:37 pm on March 25th (switched from the
seawater injection). At 8:32 am, Mar 29th, transfer from the fire
fighting pump to a temporary motor driven pump was made.
-At approximately 10:50 am on March 24th, white smoke was confirmed
arising from the top of the reactor building.
-At approximately 11:30 am, March 24th, lights in the main control room
were restored.
-At approximately 5:00 pm, March 24th, draining water from underground
floor of turbine buildings into a condenser was started and it was
paused at approximately 7:30 am, March 29th because we confirmed that
the water level reached almost full capacity of a condenser. In order to
move the water in the condenser into condensate reservoirs, water
transfer from the condensate reservoirs to suppression pool's water
surge-tanks has been conducted since around 0:00 pm, March 31st.
-From 1:03 pm, March 31st, the water spray by the concrete pumping
vehicle was started, and finished at 4:04 pm.
*Unit 2
-At 1:25 pm, March 14th, since the Reactor Core Isolation Cooling System
has failed, it was determined that a specific incident stipulated in
Clause 1, Article 15 of Act on Special Measures Concerning Nuclear
Emergency Preparedness occurred (failure of reactor cooling function).
At 5:17 pm, March 14th, while the water level in the reactor reached the
top of the fuel rod, we have restarted the water injection with the valve
operation.
-At approximately 6:14 am, March 15th, the abnormal sound was confirmed
near the suppression chamber and the pressure inside the chamber
decreased afterwards. It was determined that there is a possibility that
something happened in the suppression chamber. While sea water injection
to the reactor continued, TEPCO employees and workers from other
companies not in charge of injection work started tentative evacuation
to a safe location.
Sea water injection to the reactor continued.
-On March 18th, power was delivered up to substation for backup power
through offsite transmission line. We completed laying cable further
to unit receiving facility in the building, and at 3:46 pm, March 20th
the load-side power panel of the receiving facility started to be
energized.
-From 3:05 pm to 5:20 pm on March 20th, about 40 tons of seawater was
injected into Unit 2 by TEPCO employees.
-At approximately 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 could hardly confirm.
-From around 4:00 pm to 5:00 pm on March 22nd, approximately 18 tons of
sea water was injected into the spent fuel pool by TEPCO employees.
-From 10:10 am on March 26th, freshwater (with boric acid) injection was
initiated. (switched from the seawater injection) At 6:31pm, March 27th,
transfer from the fire fighting pump to a temporary motor driven pump was
made.
-From 10:30 am on March 25th, seawater injection through Fuel Pool
Cooling and Filtering System was initiated. The work was finished at
12:19 pm, March 25th. From 4:30 pm, March 29th, freshwater injection
through Fuel Pool Cooling and Filtering System was initiated. (We
switched from seawater to freshwater). The work was finished at 6:25 pm
on March 29th. At 9:25 am, March 30th, we started fresh water injection
by a temporary motor driven pump, but we switched the pump to the fire
fighting pump due to the pump trouble. At 1:10 pm, March 30th, freshwater
injection was suspended, because we found the crack on a part of the hose.
At 7:05 pm, March 30th, freshwater injection was resumed and finished at
11:50 pm, March 31.
-At approximately 4:46 pm, March 26th, lights in the main control room
were restored.
-At approximately 4:45 pm, March 29th, the water in condensate reservoirs
was being transferred to suppression pool water surge-tanks to prepare
for water transfer from a condenser to condensate reservoirs in order to
drain water on the underground floor of the turbine building into a
condenser. At 11:50 am, April 1st, transfer was completed.
-At 14:56 pm, April 1st, water injection into spent fuel pool in Unit 2 by
temporary motor driven pump was initiated. At 5:05 pm on April 1st, the
water injection was finished.
*Unit 3
-At 6:50 am, March 14th, while water injection to the reactor was under
operation (injection of boric acid was done on Mar 13th), the pressure in
the reactor containment vessel increased to 530 kPa. As a result, at 7:44
am, it was determined that a specific incident stipulated in article 15,
clause 1 occurred (abnormal increase of the pressure of reactor
containment vessel). Afterwards, the pressure gradually decreased (as of
9:05 am, 490 kPa).
-We continue injecting water into a reactor. (Boric acid was added on March 13)
* We announced in our past reports that "On March 14, the pressure in the
primary containment vessel increased and it was determined that a
specific incident stipulated in the Article 15, the Clause 1 of Act on
Special Measures Concerning Nuclear Emergency Preparedness occurred".
However, we made a mistake in the calculation of the pressure value and
the status of Unit 3 did not fall under the above-mentioned specific
incidents. We will delete the related description from our latest report.
-At approximately 11:01 am, March 14th, an explosion followed by white
smoke occurred near Unit 3. 4 TEPCO employees and 3 workers from other
companies (all of them were conscious) sustained injuries and were taken
to the hospital by ambulances.
-As the temperature of water in the spent fuel pool rose, spraying water
by helicopters with the support of the Self Defense Force was considered.
However the operation on March 16th was cancelled.
-At 6:15 am, March 17th, the pressure of the Suppression Chamber
temporarily increased, but currently it is stable within a certain range.
On March 20th, 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.
-In order to cool spent fuel pool, water was sprayed by helicopters on
March 17th with the cooperation of Self-Defense Forces.
-At approximately past 7:00 pm, March 17th, Self-Defense Forces and the
police started spraying water by water cannon trucks upon our request for
the cooperation. At 8:09 pm, March 17th, they finished the operation.
-At 2:00 pm, March 18th, spraying water by fire engines was started with
the cooperation of Self-Defense Forces and the United States Armed Forces.
At 2:45 pm, March 18th, the operation was finished.
-At approximately 12:30 am, March 19th, spraying water was started with
the cooperation of Fire Rescue Task Forces of Tokyo Fire Department. At
approximately 1:10 am, March 19th, the operation was finished. They
resumed spraying water at 2:10 pm and finished at approximately 3:40 am,
March 20th.
-At approximately 9:30 pm, March 20th, spraying water was started with the
cooperation of Fire Rescue Task Forces of Tokyo Fire Department. At
approximately 3:58 am, March 21st, the operation was finished.
-At approximately 3:55 pm, March 21st, light gray smoke was confirmed
arising from the southeast side of the 5th floor roof of the Unit 3
building. The situation was reported to the fire department at
approximately 4:21 pm. The parameters of reactor pressure vessel, reactor
containment vessel, and monitored environmental data remained stable
without significant change. However, employees working around Unit 3
evacuated to a safe location. On March 22nd, the color of smoke changed
to somewhat white and it is slowly dissipating.
-At approximately 3:10 pm on March 22nd, spraying water to Unit 3 by Tokyo
Fire Department's Hyper Rescue and Osaka City Fire Department was
conducted, and completed at approximately 4:00 PM on the same day.
-At approximately 10:45 pm on March 22nd, lights in the main control room
were restored.
-At 11:00 am on March 23rd, the injection of sea water to spent fuel pool
was conducted, and finished approximately at 1:20 pm on the same day.
-At 4:20 pm on March 23rd, light gray smoke was observed belching from
Unit 3 building. The situation was reported to the fire department at
4:25 pm on March 23rd. The parameters of the reactor, the reactor
containment vessel of Unit 3, and monitored figures around the site's
immediate surroundings remained stable without significant change. To be
safe, workers in the main control room of Unit 3 and around Unit 3
evacuated to a safe location. At approximately 11:30 pm on March 23rd and
4:50 am on March 24th, TEPCO employees confirmed the smoke has
disappeared. Accordingly, workers evacuation was lifted.
-From approximately 5:35 am on March 24th, sea water injection through
Fuel Pool Cooling and Filtering System was initiated, and finished at
approximately 4:05 pm on the same day.
-From 1:28 pm on March 25th, Hyper Rescue team started water spray. The
work finished at 4:00 pm on March 25th.
-From 6:02 pm on March 25th, the injection of freshwater to the reactor
was started (switched from the seawater injection). At 8:30 pm on March
28th, the injection of fresh water is switched to temporary electricity
pumps from the fire engine pumps.
-At approximately 12:34pm March 27th , the injection of water by the
concrete pump truck was started. At approximately 2:36 pm, March 27th,
the operation was finished.
-At approximately 2:17pm March 29th, the injection of fresh water by the
concrete pump truck was started. (Sea water had been injected so far and
transfer from seawater to freshwater was made). The water injection was
finished at 6:18 PM, March 29th.
-At approximately 5:40 pm, March 28th, the water in condensate reservoirs
was being transferred to suppression pool water surge-tanks to prepare
for water transfer from a condenser to condensate reservoirs in order to
drain water on the underground floor of the turbine building into a
condenser. We finished the transfer work at approximately 8:40 am, March
31st.
-From 4:30 pm, March 31st, the water spray by the concrete pumping vehicle
was started, and finished at 7:33 pm.
* Unit 4
-At approximately 6:00 am, March 15th, an explosive sound was heard and
the damage in the 5th floor roof of Unit 4 reactor building was confirmed.
At 9:38 am, the fire near the north-west part of 4th floor of Unit 4
reactor building was confirmed. At approximately 11:00 am, TEPCO
employees confirmed that the fire was out.
-At approximately 5:45 am on March 16th, a TEPCO employee discovered a
fire at the northwest corner of the Nuclear Reactor Building. TEPCO
immediately reported this incident to the fire department and the local
government and proceeded with the extinction of fire. At approximately
6:15 am, TEPCO staff confirmed at the site that there are no signs of
fire.
-At approximately 8:21 am on March 20th, spraying water by fire engines
was started with the cooperation of Self-Defense Forces and they finished
the operation at approximately 9:40 am. At approximately 6:45 pm spraying
water was started by Self-Defenses' water cannon trucks and finished at
approximately 7:45 pm.
-At approximately 6:30 am, March 21st, spraying water by fire engines was
started with the cooperation of Self-Defense Forces and the United States
Armed Forces. At approximately 8:40 am, March 21, they had finished the
operation.
-On March 21st, cabling has been completed from temporary substation to
the main power center.
-From approximately 5:20 pm on March 22nd, spraying water from the
concrete pumping vehicle was conducted and ended at approximately 8:30 pm
on the same day.
-From approximately 10:00 am on March 23rd, spraying water from the
concrete pumping vehicle was conducted and ended at approximately 1:00 pm
on the same day.
-From approximately 2:35 pm on March 24th, spraying water by the concrete
pumping vehicle was conducted and ended at approximately 5:30 pm on the
same day.
-From 6:05 am on March 25th, seawater injection through Fuel Pool Cooling
and Filtering System was initiated and finished at approximately 10:20 am
on the same day.
-From 7:05 pm on March 25th, water spray by the concrete pumping vehicle
was started and finished at 10:07 pm on March 25th.
-From 4:55 pm on March 27th, water spray by the concrete pumping vehicle
was started and finished at 7:25 pm on March 27th.
-At approximately 11:50 am on March 29th, lights in the main control room
were restored.
-From 2:04 pm on March 30th, water spray by the concrete pumping vehicle
was started and finished at 6:33 pm on March 30th.
-From 8:28am, April 1st, the water spray by the concrete pumping vehicle
was started. At 14:14 pm, the water spray finished.
*Unit 5 and 6
-At 5:00 am on March 19th, we started the Residual Heat Removal System
Pump (C ) of Unit 5 in order to cool the spent fuel pool. At 10:14 pm,
we started the Residual Heat Removal System Pump (B ) of Unit 6 in order
to cool the spent fuel pool.
-Unit 5 has been in reactor cold shutdown since 2:30 pm on March 20th.
Unit 6 has been in reactor cold shutdown since 7:27 pm on March 20th.
-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.
-At approximately 5:24 pm on March 23rd, the temporary Residual Heat
Removal System Seawater Pump automatically stopped when its power source
was switched. We restarted the pump at around 4:14 pm, March 24th, and
resumed cooling of reactor at around 4:35 pm.
*On March 18th, regarding the spent fuel in the common spent fuel pool,
we have confirmed that the water level of the pool is secured. At around
10:37 am March 21st, water spraying to common spent fuel pool and
finished at 3:30 pm. At around 6:05 pm, fuel pool cooling pump was
started to cool the pool.
*common spent fuel pool: a spent fuel pool for common use set in a
separate building in a plant site in order to preserve spent fuel which
are transferred from the spent fuel pool in each Unit building.
*On March 17th, we patrolled buildings for dry casks and found no signs of
abnormal situation for the casks by visual observation. A detailed
inspection is under preparation.
*dry cask: a measure to store spent fuel in a dry storage casks in
storages. Fukushima Daiichi Nuclear Power Station started to utilize the
measure from August 1995.
*On March 21st, 23rd to 30th, we detected technetium, cobalt, iodine,
cesium, tellurium, barium, lanthanum and molybdenum from the seawater
around the discharge canal of the station.
*On March 20th, 21st, 23rd to 30th, we detected iodine, cesium, tellurium
and ruthenium in the air collected at the site of Fukushima Daiichi
Nuclear Power Station.
*Plutonium has detected from the sample of soil at the site of Fukushima
Daiichi Nuclear Power Station collected on 21st and 22nd of March,
Concentration level of Plutonium detected was same as that of under usual
environment and it is thought not to be harmful to human health. We will
strengthen environmental monitoring of power station and surrounding
environment.
*We detected radioactive materials contained in the puddles found in the
turbine building of Unit 1 to 4.
*At approximately 3:30 pm, March 27th, we found water pooling in the
vertical shaft of the trench outside of the turbine buildings for Units 1
to 3. The radiation dose at the surface of the water amounted 0.4 mSv/h
in Unit 1 and over 1,000 mSv/h in Unit 2. We could not confirm the amount
of the radiation dose in Unit 3. We will keep observing the condition of
the water in the vertical shaft.
On March 29th, we detected niobium, tellurium, ruthenium, silver,
tellurium, iodine, cesium, and ruthenium in the water collected at the
trench of unit 1.
On March 30th, we took samples from the water in the trench of Unit 2 and
3, and conducted nuclide analysis on them. We are now confirming the
results of the analysis.
*Since around 9:20 am, March 31st, the water transfer from the vertical
shaft of Unit 1 to the reservoir of the centralized environmental
facility was conducted. We finished the task around 11:25 am of the same
day.
*We found a puddle of water at the main building of the centralized
environmental facility process. We analyzed and detected approximately
1.2 x 101Bq/cm3 of radioactivity in full dose in the Controlled Area and
2.2 x 101Bq/cm3 in full dose in the Non-Controlled Area on March 29.
*A barge of the U.S. Forces with fresh water to be used to cool down
reactors etc. was towed by a ship of Maritime Self-Defense Force and at
3:42 pm on March 31st 2011, came alongside the pier. At 15:38, April 1st,
we started to replenish the fresh water with filtrate tanks.
*At 11:35 am, April 1st, a worker fell into the sea while stepping into
the ship from the pier during the hose laying work of the barge. Other
crew immediately rescued the worker. While no injury or contamination was
confirmed, whole body counter will be implemented to check the
contamination inside the body just in case.
*From 3:00 pm, April 1st, we started spraying inhibitor in order to
prevent diffusion of radioactive materials. This attempt was conducted on
a trial basis at the mountain side area of the common spent fuel pool in
the range of 500m2. The spraying finished at 4:05 pm.
*Monitoring posts (no.1 to no.8) which were installed around the site
boundary have been restored. We will continue monitoring the measured
value and make announcements on those values accordingly.
*We will continuously endeavor to securing safety, and monitoring of the
surrounding environment.
Fukushima Daini Nuclear Power Station:
Units 1 to 4: shutdown due to the earthquake
*The national government has instructed evacuation for those local
residents within 10km radius of the periphery.
*In order to achieve cold shutdown, reactor cooling function was
restored and cooling of reactors was conducted. As a result, all reactors
achieved cold shutdown: Unit 1 at 5:00 pm, March 14th, Unit 2 at 6:00 pm,
March 14th, Unit 3 at 0:15 pm, March 12th, Unit 4 at 7:15 am, March 16th.
*At 2:30 pm on March 30th, the power source of the residual heat removal
system(B) to cool the reactor of Unit 1 was secured from an emergency
power source in addition to an offsite power. This means that all the
units secure backup power sources (emergency power sources) for the
residual heat removal systems(B).
*(Unit 1)
As it is confirmed that the temperature of the Emergency Equipment
Cooling Water System *1 has increased, at 3:20 pm, March 15th, we stopped
the Residual Heat Removal System (B) for the inspection. Subsequently,
failure was detected in the power supply facility associated with the
pumps of the Emergency Equipment Cooling Water System. At 4:25 pm, March
15th, after replacing the power facility, the pumps and the Residual Heat
Removal System (B) have been reactivated.
*(Unit 4)
As it is confirmed that the pressure at the outlet of the pumps of the
Emergency Equipment Cooling Water System*1 has been decreased, at 8:05 pm,
March 15th, we stopped the Residual Heat Removal System (B) for the
inspection. Subsequently, failure was detected in the power supply
facility associated with the pumps of the Emergency Equipment Cooling
Water System. At 9:25 pm, March 15th, after replacing the relevant
facility, the pumps and the Residual Heat Removal System (B) have been
reactivated.
*1:emergency water system in which cooling water (pure water) circulates
which exchanged the heat with sea water in order to cool down bearing
pumps and/or heat exchangers etc.
Kashiwazaki Kariwa Nuclear Power Station:
Units 1, 5, 6, 7: normal operation
(Units 2 to 4: outage due to regular inspection)
[Thermal Power Station]
-Hirono Thermal Power Station Units 2 and 4: shutdown due to the
earthquake
-Hitachinaka Thermal Power Station Unit 1: shutdown due to the earthquake
-Kashima Thermal Power Station Units 2, 3, 5, 6: shutdown due to the
earthquake
[Hydro Power Station]
-All the stations have been restored.
(Facilities damaged by the earthquake are now being repaired in a timely
manner.)
[Transmission System, etc.]
-All substation failed due to the earthquake have been restored.
(Facilities damaged by the earthquake are now being repaired in a timely
manner.)
[Supply and Demand Status within TEPCO's Service Area to Secure Stable
Power Supply]
-Considering the critical balance of our power supply capacity and
expected power demand forward, in order to avoid unexpected blackout,
TEPCO has been implementing rolling blackout (planned blackout alternates
from one area to another) since Mar 14th. We will make our utmost to
secure the stable power supply as early as possible. For customers who
will be subject to rolling blackout, please be prepared for the announced
blackout periods. Also for customers who are not subject to blackouts,
TEPCO appreciates your continuous cooperation in reducing electricity
usage by avoiding using unnecessary lighting and electrical equipment.
[Others]
-Please do NOT touch cut-off electric wires.
-In order to prevent fire, please make sure to switch off the electric
appliances such as hair driers when you leave your house.
-For the customer who has in-house power generation, please secure fuel
for generator.
* Revised past progress