Print

Language



Corporate Information

 
Press Release (Mar 30,2011)
Status of TEPCO's Facilities and its services after the Tohoku-Taiheiyou-Oki Earthquake(as of 10:00PM)
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 was connected to Unit 1 to 6. 

* 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. Water 
  transfer from condensate reservoirs to suppression pool water surge-tanks 
  is under review to enable water transfer from a condenser to condensate 
  reservoirs. 

* 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 pm to 5 pm on March 22nd, approximately 18 tons of sea 
  water was injected into the spent fuel pool by TEPCO employees. 
- From 10:30 am on March 25th, seawater injection through Fuel Pool Cooling 
  and Filtering System was initiated. The work was finished at 0:19 pm on 
  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. 
- From 10:10 am on March 26th, freshwater (with boric acid) injection was 
  initiated. (switched from the seawater injection) At 06:31pm, Mar 27th, 
  transfer from the fire fighting pump to a temporary motor driven pump was 
  made. At 9:25 am, March 30th, transfer from a temporary motor driven pump  
  to the fire fighting pump was made due to pump trouble. At 1:10 pm, March 
  30th, freshwater injection was paused due to hose trouble. At 7:05 pm,  
  March 30th, freshwater injection was resumed. 
- At approximately 4:46 pm, March 26th, lights in the main control room 
  were restored.
- At approximately 4:45 pm, March 29th, water transfer from condensate 
  reservoirs to suppression pool water surge-tanks was initiated to enable 
  water transfer from a condenser to  condensate reservoirs in order to 
  drain water from underground floor of turbine buildings into a condenser. 

* 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, water transfer from condensate 
  reservoirs to suppression pool water surge-tanks was initiated to enable 
  water transfer from a condenser to  condensate reservoirs in order to 
  drain water from underground floor of turbine buildings into a condenser. 

* 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. 

* Unit 5 and 6
- At 5 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.

* In total 13 fire engines are lent for spraying water 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.

* On March 21st, 23rd to 29th, we detected technetium, cobalt, iodine, 
  cesium, tellurium, barium, lanthanum and molybdenum from the seawater 
  around discharge canal of Unit 1, 2, 3 and 4.

* On March 20th, 21st, 23rd to 29th, 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.

* On March 28th, 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 28th, a puddle of water was found at a centralized 
  environmental facility process main building. As a result of a 
  radioactivity analysis, on March 29th, we detected approximately 1.2 x 
  10Bq/cm3 in a full dose at a radiation controlled area and 2.2 x 
  10Bq/cm3 in a full dose at a non-controlled area. 

* At 12:03 pm, March 29th, when taking off the flange of the pipe of the 
  seawater piping of the Residual Heat Removal System, 3 workers from our 
  subcontractor were soaked with water in the pipe. After wiping the water 
  off, we confirmed that there was no radioactive contamination to their 
  bodies.
  
* 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 residual heat removal system(B) that is 
  cooling the reactor of Unit 1 was also enabled to be energized by 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.)
[Power Supply to TEPCO's Service Areas] 
- Except in case of planned rolling blackouts, we can supply electricity to 
  our all service areas.
[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
back to page top