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Press Release (Apr 09,2011)
Status of TEPCO's Facilities and its services after the 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 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 Units 1 to 6 by March 22nd, 2011.

* Unit 1
-The explosive sound and white smoke was confirmed near Unit 1 when the 
 big quake occurred at 3:36 pm, 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. From 10:42am to 
 11:52am on April 3rd we temporarily switched the pump to the fire 
 fighting pump to inject fresh water to use power through off-site 
 transmission line. We're now injecting fresh water to the reactor by a 
 motor driven pump powered by off-site transmission line.
-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 a condensate storage tank, water 
 transfer from the condensate storage tank to suppression pool's water 
 surge-tanks was conducted from around 0:00 pm, March 31st to 3:26 pm, 
 April 2nd.
-From 1:03 pm, March 31st, the water spray by the concrete pumping 
 vehicle was started, and finished at 4:04 pm.
-In order to confirm the position of water spray to the spent fuel pool 
 by the concrete pumping vehicle, the water spray was conducted from 
 5:16 pm to 5:19 pm.
-Some of turbine building lights were turned on April 2nd.
-The water transfer from the condenser to the condensate storage tank has 
 been implemented since 1:55 pm, April 3rd.
-As it is suspected that hydrogen gas may be accumulated inside reactor 
 containment vessel, at 10:30 pm, April 6th, we started the operation of 
 the valve for the injection of nitrogen to the reactor in order to 
 prevent the increase of oxygen density. Following this, the injection of 
 nitrogen to the reactor was started at 1:31 am, April 7th. 

* 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 was 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 approximately 3:05 pm to approximately 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 10:22am to 0:06pm on April 3rd, we temporarily switched 
 the pump to the fire fighting pump to inject fresh water to use power 
 through off-site transmission line. We're now injecting fresh water to 
 the reactor by a motor driven pump powered by off-site transmission line.
-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 a condensate storage 
 tank was being transferred to suppression pool water surge-tanks to 
 prepare for water transfer from a condenser to a condensate storage tank 
 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 2:56 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.
-The water transfer from the condenser to the condensate storage tank has 
 been implemented since 5:10 pm, April 2nd.
-Some of turbine building lights were turned on April 2nd.
-At 11:05 am, April 4th, water injection into spent fuel pool in Unit 2 
 by a temporary motor driven pump was initiated. At 1:37 pm, April 4th, 
 the water injection was finished.
-At 1:29 pm, April 7th, water injection into spent fuel pool in Unit 2 by 
 a temporary motor driven pump was initiated. At 2:34 pm, April 7th, 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 was 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.
-Before 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 was 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 approximately 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 was switched to temporary electricity 
 pumps from the fire engine pumps. From 10:03am to 0:16pm on April 3rd, 
 we temporarily switched the pump to the fire fighting pump to inject 
 fresh water to use power through off-site transmission line. We're now 
 injecting fresh water to the reactor by a motor driven pump powered by 
 off-site transmission line.
-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 a condensate storage 
 tank was being transferred to suppression pool water surge-tanks to 
 prepare for water transfer from a condenser to a condensate storage tank 
 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.
-From 9:52 am, April 2nd, the water spray by the concrete pumping vehicle 
 was started, and finished at 0:54 pm.
-Some of turbine building lights were turned on April 2nd. 
-From 5:03 am, April 4th, the water spray by the concrete pumping vehicle 
 was started, and finished at 07:19 pm.
-From 6:53 am, April 7th, water spray by the concrete pumping vehicle was 
 started, and finished at 8:53 am.
-From 5:06 pm, April 8th, water spray by the concrete pumping vehicle was 
 started, and finished at 8:00 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 were 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.
-Some of turbine building lights were turned on March 31st.
-From 8:28 am, April 1st, the water spray by the concrete pumping vehicle 
 was started. At 2:14 pm, the water spray finished.
-From 5:14 pm, April 3rd, the water spray by the concrete pumping vehicle 
 was started. At 10:16 pm, the water spray finished.
-From 5:35 pm, April 5th, the water spray by the concrete pumping vehicle 
 was started. At 6:22 pm, the water spray finished.
-From 6:23 pm, April 7th, the water spray by the concrete pumping vehicle 
 was started. At 7:40 pm, the water spray finished.

* Units 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 was 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 was 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 April 7th we detected radioactive materials in the 
sea water. The data of the detected three nuclides (Iodine- 131, 
 Cesium- 134 and Cesium- 137) will be reported as fixed data. Other nuclides 
 figures are to be re-evaluated based on the improved measures for 
 recurrence prevention which have been prepared in accordance to a strong 
 warning by NISA on April 1. 
 
*On March 20th, 21st, 23rd to April 7th, we detected radioactive materials 
 in the air collected at the site of Fukushima Daiichi Nuclear Power 
 Station. The data of the detected three nuclides (Iodine- 131, Cesium- 134 
 and Cesium- 137) will be reported as fixed data. Other nuclides figures 
 are to be re-evaluated based on the improved measures for recurrence 
 prevention which have been prepared in accordance to a strong warning by 
 NISA on April 1. 
 
*Plutonium has been detected from the sample of soil at the site of 
Fukushima Daiichi Nuclear Power Station collected on 21st, 22nd, 25th and 
28th of March, Concentration level of Plutonium detected was same as that 
of under usual environment and it was thought not to be harmful to human 
health. We will strengthen environmental monitoring of power station and 
surrounding environment.
Additionally Iodine, Cesium, Tellurium, Barium, Niobium, Ruthenium, 
Molybdenum, Technetium, Lanthanum, Beryllium, Silver have been detected 
from the sample of soil collected at Fukushima Daiichi Nuclear Power 
Station on 21st, 22nd, 25th and 28th of March.

*We detected radioactive materials contained in the puddles found in the 
turbine building of Unit 1 to 4. We are planning to conduct water analysis 
in preparation for treating the water. The analysis will be carried out in 
Fukushima Daini Nuclear Power Station with support from other nuclear 
companies (Japan Atomic Energy Agency, Japan Nuclear Fuel Limited).

*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.

*At approximately 9:30 am, April 2nd, we found that there was water in the 
shaft for storing power cable (concrete product) near the intake of water 
for Unit 2, the radioactive air dose was over 1,000mSv/h and the water 
spilled into the sea from the crack (approximately 20 cm) on the side of 
the shaft. We injected fresh concrete to the shaft twice, however, we 
could not observe a change in the amount of water flowing into the sea. 
Therefore, we considered that a new method of stopping the water and 
determined to use the polymer. Necessary equipment and experts of water 
shutoff will be dispatched to the site and after checking the condition, 
we began to stop water shutoff and were injecting polymer on April 3rd. On 
April 4th, we injected the tracer from the vertical shaft of the trench to 
start to examine the water current. We did not observe reduction of flow or
change of color or water leaking. We checked the diagram and confirmed the 
route. At the same time, we checked the situation of the pit in detail and 
considered the possibility that the water was not from the pit, rather, 
from the joint between the piping upstream of the pit and the duct, then 
the water seeped through a layer of gravel below the piping. In order to 
stop that seepage from the layer of gravel, we decided to conduct the 
water sealing to the bedrock around the piping. We arranged for the 
specialist and gathered equipments. On April 5th, liquid glass was 
injected to the bedrock. Tracer was put through the two new holes drilled 
near the pit to investigate the water flow. At 2:15 pm, April 5th, it was 
observed the water with tracer came out from the crack on the concrete 
wall of the pit. At 3:7 pm, April 5th, injection of coagulant from the 
holes was initiated and we have confirmed the outflow from the crack on 
the concrete wall of the pit has stopped at 5:38 am, April 6th. We 
confirmed water level has not been rising in the turbine building of 
unit 2. On April 6th, a countermeasure by using rubber plate and fixer was 
implemented to prevent discharge of radioactive materials, and we are 
continuously monitoring for any existence of leakage. From 3:00pm April 
5th, a construction of installing large sandbags around the pier to 
prevent the outflow of the contaminated water from station's port on the 
south side to the ocean was started. Also we are preparing spillage 
prevention fences as countermeasures for lowering the outflow to the ocean.
Iodine and Cesium were detected from the water sampled in the pit and in 
the sea near the water discharge. Additional nuclide analysis will be 
implemented.
In addition, from April 2nd, we will implement sampling at 15km offshore 
Fukushima Daiichi and Fukushima Daini Nuclear Power Stations(3 points have 
been added since April 5th) and will evaluate these samples 
comprehensively.

*Since approximately 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.
From April 3rd, the water level in the trench of Unit 3 increased by 
15 cm. The route is not yet known, but there is a possibility that water 
in the turbine building of Unit 4 may be running to the trench of Unit 3. 
To be safe, at 09:22am, April 4th, we stopped transferring water to the 
turbine building of Unit 4. At this moment, the water level in the trench 
of Unit 3 became stable after stopping the water transfer.

*There is plenty of radioactive wastewater in the turbine buildings. 
Especially, Unit 2's wastewater is very highly radioactive. To store this 
stably, it was decided that this needed to be transferred to the Central 
Radioactive Waste Disposal Facility. However, within that facility, we are 
storing ten thousand tons of low level radioactive wastewater. In order to 
transfer more wastewater, we need to discharge the low level radioactive 
wastewater. In addition, as low radioactive subsurface water is piling up 
in sub-drain pits of Units 5 and 6 and a part of subsurface water is 
running into buildings. We are concerned that important equipment to 
secure the safety of reactors may be submerged. 
Based on the Section 1 of the Article 64 of the Nuclear Reactor Regulation 
Law, we have decided to discharge to the sea approximately ten thousand 
tons of the accumulated low level radioactive water and a total of fifteen 
hundred tons of the low level radioactive subsurface water stored in the 
sub drain pits of Unit 5 and 6 as soon as we get ready. 
From 7:03 pm, April 4th, we are discharging the low level radioactive 
wastewater stored in the Central Radioactive Waste Disposal Facility to 
the south of the water discharge canal. By 7:10 pm, we started ten pumps. 
Also, from 9:00 pm, April 4th, we are discharging the low level 
radioactive wastewater stored in the sub drain pits of Unit 5 and 6 by 
using one pump via the water discharge canal of Units 5 and 6. 
We evaluate the impact on the discharge of the low radioactive wastewater 
to the sea as approximately 0.6 mSv per year per an adult if an adult eats 
adjacent fish and seaweeds everyday. The amount (0.6 mSv of effective 
radioactive doses per year) is one-forth of annual radioactive dose 
(2.4 mSv) to which the general public is exposed from nature.

*The first 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 
docked at 3:42 pm on March 31st 2011. At approximately 3:58 pm, April 1st, 
we started to replenish filtrate tanks with the fresh water, and finished 
at 4:25 pm. At approximately 10:20 am, April 2nd, we resumed replenishing 
filtrate tanks with the fresh water, and finished at 4:40 pm. 
The second barge of the U.S. Forces with the fresh water towed by the ship 
of Maritime Self-Defense Force came alongside the pier at approximately 
9:10 am, April 2nd. It was in preparation for replenishing filtrate tanks 
with the fresh water. We began to transfer fresh water from the second 
barge to the first barge on April 3rd at 9:52 am and continued until 
11:15 am on April 3rd.

*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 has been 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. On April 5th and 6th ,
we also sprayed the inhibitor in order to prevent the spread of 
radioactive materials on a trial basis at the mountain side area of the 
common spent fuel pool in the range of 600m2. On April 8th, we conducted 
trial spraying of the inhibitor at the mountain side area of the common 
spent fuel pool in the range of 500m2.

*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.

*No damage has been done to the power station by the magnitude 7.4 
earthquake occurred at approximately 11:32 pm, April 7th in the offshore 
of Miyagi Prefecture.

*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 system (B).

* Unit 1
As it was 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 was 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)

*No damage has been done to the power station by the magnitude 7.4 
earthquake occurred at approximately 11:32 pm, April 7th in the offshore 
of Miyagi Prefecture. 
[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 6: shutdown due to the earthquake 
[Hydro Power Station] 
-Power supply has returned to normal, but facilities damaged by the 
 earthquake are now being handled in a timely manner. 
[Impacts on Transmission Facilities] 
-Power supply has returned to normal, but facilities damaged by the 
 earthquake are now being handled in a timely manner. 
[Avoidance of further Implementation on Planned Rolling Blackouts and 
 Request for Conserving Electricity Consumption] 
Currently, we are giving our utmost efforts to restore power supply after 
our nuclear and thermal power facilities are severely damaged by 
Tohoku-Taiheiyou-Oki Earthquake. The widespread understanding and 
cooperation to the conservation of electricity among each customer have 
contributed to the improvement in the tight power supply-demand balance.
Amidst this backdrop, in principle, we have decided not to implement 
further rolling blackouts.
However, we must sincerely ask for your continued cooperation in 
conserving electricity consumption due to the possible increase in demand 
caused by abrupt climate change or unexpected trouble in power stations 
that are currently being restored. In case the electricity supply-demand 
balance becomes tighter than expected, on the condition of prior 
announcement, we may reluctantly implement the rolling blackouts. We 
kindly ask for your cooperation.
Also, we will give our utmost efforts to maintain this policy of avoiding 
further implementation on rolling blackouts in summer. 

* Revised past progress 
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