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Press Release (Mar 29,2011)
Status of TEPCO's Facilities and its services after Tohoku-Taiheiyou-Oki Earthquake (as of 9:00AM)
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 earthquake 
   (Units 4 to 6: outage due to regular inspection) 

*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 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.
 
*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, 40 tons of seawater was injected 
 into Unit 2 by TEPCO employees.
-At 6:20 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 finished at 0:19 pm 
 on March 25th.
-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 approximately 4:46 pm, March 26th, lights in the main control room 
 were restored.

*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 0:30 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, 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 operation 
 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 0:34pm March 27th , Injection of water by concrete pump 
 truck was started. At approximately 2:36 pm, March 27th, the operation 
 was finished. 

*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. 

*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 27th, 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 27th, 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. 

*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 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. 

*Since March 12th, we had been preparing measures for reducing the 
pressure of reactor containment vessels (partial discharge of air 
containing radioactive materials to outside), but on March 17th, we 
stopped such preparation in all Units. 

*(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 earthquake 
-Hitachinaka Thermal Power Station Unit 1: shutdown due to earthquake 
-Kashima Thermal Power Station Units 2, 3, 5, 6: shutdown due to 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.)
[Blackout in TEPCO's Service Area] 
-All the blackouts are resolved.
[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 
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