Japanese Earthquake, Tsunami, and Nuclear Reactors

UPDATE AS OF 10:00 A.M. EDT, WEDNESDAY, MARCH 16:

News reports that high radiation levels led to the evacuation of all workers from the Fukushima Daiichi nuclear power station are not accurate. Workers were evacuated for about an hour but returned to the site to continue efforts to restore safe conditions at the plant.

Restoration of electrical power to the site was under way at the Daiichi plant as of 6:00 a.m. EDT Wednesday. A temporary cable was being connected between an off-site power line and Daiichi reactor 3. Off-site power has not been available at the site since the earthquake on March 11

Reactors 1, 2 and 3 at the plant are being cooled with seawater. There is some level of uranium fuel damage at all three units, and containment structure damage is suspected at reactor 2

Before the earthquake, reactor 4 had been in refueling and was completely defueled. Attempts to provide cooling water to the used fuel pool at reactor 4 by helicopter were not successful. Preparations are being made to inject water into the fuel storage pool using a high-capacity spray pump. There have been two fires inside the reactor containment building at reactor 4, but they have been extinguished. Although the reactor containment building at Unit 4 was damaged, the primary containment vessel remains intact

At the Fukushima Daini site, all four reactors are safely shut down and cooling functions are being maintained

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.Japanese authorities have reported concerns about the condition of the spent nuclear fuel pool at Fukushima Daiichi Unit 3 and Unit 4. Japanese Defense Minister Toshimi Kitazawa announced Wednesday that Special Defence Forces helicopters planned to drop water onto Unit 3, and officials are also preparing to spray water into Unit 4 from ground positions, and possibly later into Unit 3. Some debris on the ground from the 14 March explosion at Unit 3 may need to be removed before the spraying can begin.



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NEI
Fact Sheet
Industry Taking Action to Ensure Continued Safety at U.S. Nuclear Energy Plants
(Last updated 3/16/11)

(Last updated 3/16/11)
The nuclear energy industry’s priority remains providing Japan with the support necessary to maintain safety at the Fukushima reactors.
Even though the full extent of damage to these reactors still is unknown, the events represent a significant challenge to the structural integrity and safety of the plant. As more is learned about the Japanese events, more long-term corrective actions will be developed.
Senior executives representing all U.S. nuclear power plants are taking the following actions at each of their sites:
1.
Verify each company’s capability to mitigate conditions that result from severe adverse events, including the loss of significant operational and safety systems due to natural events, fires, aircraft impact and explosions. Specific actions include testing and inspecting equipment required to mitigate these events and verifying that qualifications of operators and support staff required to implement them are current.
2.
Verify that the capability to mitigate a total loss of electric power to a nuclear power plant is proper and functional. This will require inspections verifying that all required materials are adequate and properly staged and that procedures are implemented.
3.
Verify the capability to mitigate flooding and the impact of floods on systems inside and outside the plant. Specific actions include verifying required materials and equipment are properly located to protect them from flood.
4.
Perform walk downs and inspection of important equipment needed to successfully respond to fire and flood events. Identify the potential that the equipment’s function could be lost during seismic events appropriate for the site and develop mitigating strategies for potential vulnerabilities.

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Japanese authorities have reported concerns today about the condition of the used nuclear fuel pools at Fukushima Daiichi reactor 3 and reactor 4.

Officials also are preparing to spray water into reactor 4 from ground positions and possibly later into reactor 3. Some debris on the ground from the March 14 explosion at reactor 3 may need to be removed before the spraying can begin.

Most plants store used fuel in steel-lined, concrete vaults filled with water, which acts as a natural barrier for radiation from the used fuel. The water also keeps the fuel cool while the radiation decays-or becomes less radioactive. The water itself does not leave the used fuel pool.

Used nuclear fuel at the Fukushima-Daiichi plant is stored in seven pools (one at each reactor and a shared pool) and in a dry container storage facility (containing nine casks.)

The used fuel pools are designed so that the water in the pool cannot drain down as a result of damage to the piping or cooling systems. The pools do not have drains in the sides or the floor of the pool structure. The only way to rapidly drain down the pool is to have structural damage of the walls or the floor.

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Fact Sheet
Used Nuclear Fuel Storage at the Fukushima Daiichi Nuclear Power Plant
(Last updated 3/16/11, 3:40 p.m.)
Key Facts
��
Used nuclear fuel at the Fukushima-Daiichi plant is stored in seven pools (one at each reactor and a shared pool) and in a dry container storage facility (containing nine casks).
��
Sixty percent of the used fuel on site is stored in the shared pool, in a building separated from the reactor buildings; 34 percent of the used fuel is distributed between the six reactor fuel storage pools, and the remaining 6 percent is stored in the nine dry storage containers.
��
Used fuel pools are robust concrete and steel structures designed to protect the fuel from even the most severe events. Pools are designed with systems to maintain the temperature and level of the water sufficient to provide cooling and radiation shielding.
��
The water level in a used fuel pool typically is 16 feet or more above the top of the fuel assemblies.
��
The used fuel pools at the Fukushima Daiichi reactors are located at the top of the reactor building for ease of handling during refueling operations.
��
The used fuel pools are designed so that the water in the pool cannot drain down as a result of damage to the piping or cooling systems. The pools do not have drains in the sides or the floor of the pool structure. The only way to rapidly drain down the pool is to have structural damage of the walls or the floor.
What Could Happen During an Accident?
��
The systems that cool and maintain water levels in the pools are designed to withstand severe events. If these systems are unable to function, the heat generated by the used fuel would result in a slow increase in the temperature of the spent fuel pool water. The operating temperature of the pools is typically around 40 degrees C or 100 degrees F (the boiling point for water is 100 C or 212 F). This slow increase in temperature will result in an increased evaporation rate. Rapid evaporation of the water will not occur.
��
Exact evaporation rates would depend on the amount of used fuel in the pool and how long it has cooled. The rate at which the pool water level would decrease (due to evaporation or mild boiling) in the absence of cooling system function would not be expected to lower water levels by more than a few percent per day. Given that there is approximately 16 feet of water above the used fuel assemblies, operators would have a few weeks to find another way to add water to the pools before the fuel would become exposed. For example, water could easily be added using a fire hose.
��
If the water level decreases below the top of the fuel assembly, oxidation of the zirconium cladding could occur. This oxidation could result in some hydrogen generation. The rate of hydrogen generation depends on the temperature of the fuel assembly, with hotter temperatures leading to higher gas generation rates. However, only the fuel assemblies with the least cooling time would be
1
2
susceptible to this oxidation and the temperature of the fuel assemblies decreases exponentially with cooling time.
��
Even if the water level in the pools was to decrease sufficiently so that the fuel were exposed to air, the same level of overheating that can occur in a reactor accident would not occur in the used fuel pool because the used fuel assemblies in the pool are cooler than the assemblies in the reactor. It is highly unlikely that used fuel temperatures could reach the point where melting could occur, although some damage to the cladding cannot be ruled out. The likelihood of cladding damage, as with hydrogen generation, decreases substantially with temperature and cooling time.
��
At the surface of the used fuel pool, the gamma dose rate from radiation emanating off the used fuel assemblies is typically less than 2 millirem per hour. If the water level decreases, the gamma radiation level would increase

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Temperature of Spent Fuel Pools at Fukushima Daiichi Nuclear Power Plant



Spent fuel that has been removed from a nuclear reactor generates intense heat and is typically stored in a water-filled spent fuel pool to cool it and provide protection from its radioactivity. Water in a spent fuel pool is continuously cooled to remove heat produced by spent fuel assemblies. According to IAEA experts, a typical spent fuel pool temperature is kept below 25 ˚C under normal operating conditions. The temperature of a spent fuel pool is maintained by constant cooling, which requires a constant power source.



Given the intense heat and radiation that spent fuel assemblies can generate, spent fuel pools must be constantly checked for water level and temperature. If fuel is no longer covered by water or temperatures reach a boiling point, fuel can become exposed and create a risk of radioactive release. The concern about the spent fuel pools at Fukushima Daiichi is that sources of power to cool the pools may have been compromised.



The IAEA can confirm the following information regarding the temperatures of the spent nuclear fuel pools at Units 4, 5 and 6 at Fukushima Daiichi nuclear power plant:



Unit 4

14 March, 10:08 UTC: 84 ˚C

15 March, 10:00 UTC: 84 ˚C

16 March, 05:00 UTC: no data



Unit 5

14 March, 10:08 UTC: 59.7 ˚C

15 March, 10:00 UTC: 60.4 ˚C

16 March, 05:00 UTC: 62.7 ˚C



Unit 6

14 March, 10:08 UTC: 58.0 ˚C

15 March, 10:00 UTC: 58.5 ˚C

16 March, 05:00 UTC: 60.0 ˚C



The IAEA is continuing to seek further information about the water levels, temperature and condition of all spent fuel pool facilities at the Fukushima Daiichi nuclear power plant.



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All 6 units of Fukushima Daiichi Nuclear Power Station have been shut
down.

Unit 1(Shut down)
-Reactor has been shut down. However, the explosive sound and white
smoke were confirmed after the big quake occurred at 3:36PM Mar 12th.
It was assumed to be hydrogen explosion and currently under the
investigation.
-We have been injecting sea water into the reactor pressure vessel.

Unit 2(Shut down)
-Reactor has been shut down and Reactor Core Isolation Cooling System
has been injecting water to the reactor. However, reactor pressure has
increased because the system stopped, causing reactor water level to
drop. Following the instruction by the government and with fully
securing safety, measure to lower the pressure level within the reactor
containment vessel and injection of sea water were taken, reactor
pressure and water level resumed.
-We are continuing the injection of sea water into the reactor.
-At approximately 6:00am, an abnormal noise began emanating from nearby
Pressure Suppression Chamber and the pressure within this chamber
decreased.
-While we continue sea water injection operations, the temporary
transfer of TEPCO employees and workers from other companies not
directly involved in this work has begun.

Unit 3(Shut down)
-Reactor has been shut down. However, the explosive sound and white
smoke were confirmed at 11:01AM Mar 14th. It was assumed to be hydrogen
explosion and currently under the investigation.
-As fog like steam was confirmed from reactor building at 8:30AM on
March 16th, we transferred the workers to safe area. After that, we
decided to discharge water to the upper side of reactor building by
helicopters, but could not do that because there was a trouble with
implementation of work.
-We plan to discharge water in order to cool spent fuel pool after we
complete the preparations by confirming the process of discharging,
personnel, and a situation of the site.
-We continue monitoring as it was reported that the pressure of the
Suppression Chamber temporally increased at around 6:15AM on March 17th.
-We have been injecting sea water into the reactor pressure vessel.

Unit 4 (shut down due to regular inspection)
-Reactor has been shut down. However, we have confirmed the sustained
damage around the 5th floor rooftop area of the Nuclear Reactor
Building.
-Afterwards, we confirmed the outbreak of fire at the northwestern part
of Nuclear Reactor Building. We immediately reported this matter to the
fire department and the related authorities.
-However, at approximately 11:00am, when TEPCO employee arrived at the
seen to confirm, the fire had already died down. At 5:45AM on March
16th, we confirmed the outbreak of the fire again but could not confirm
it at 6:15AM. We will continue to monitor the situation carefully.

Unit 5 (outage due to regular inspection)
-Reactor has been shut down and sufficient level of reactor coolant to
ensure safety is maintained.
-Currently, we do not believe there is any reactor coolant leakage
inside the reactor containment vessel.

Unit 6 (outage due to regular inspection)
-Reactor has been shut down and sufficient level of reactor coolant to
ensure safety is maintained.
-Currently, we do not believe there is any reactor coolant leakage
inside the reactor containment vessel.

Casualty
-2 workers of cooperative firm were injured at the occurrence of the
earthquake, and were transported to the hospital.
-1 TEPCO employee who was not able to stand by his own with his hand
holding left chest was transported to the hospital by an ambulance.
-1 subcontract worker at important earthquake-proof building was
unconscious and transported to the hospital by an ambulance.
-The radiation exposure of 1 TEPCO employee, who was working inside the
reactor building, exceeded 100mSv and was transported to the hospital.
-2 TEPCO employees felt bad during their operation in the central control
rooms of Unit 1 and 2 while wearing full masks, and were transferred to
Fukushima Daini Power Station for consultation with a medical advisor.
-4 workers were injured and transported to the hospital after explosive
sound and white smoke were confirmed around the Unit 1.
-11 workers were injured and transported to Fukushima Daini Nuclear
Power Station after explosive sound and white smoke were confirmed
around the Unit 3.One of the injured workers got medical treatment on
March 16th, but the worker reported a flank pain. We required to the
offsite center that the worker should be transported to the hospital.
After that, the helicopter of JSDF arrived and transported the worker
to the FUKUSHIMA Medical University Hospital at 10:56AM
-Presence of 2 TEPCO employees at the site is not confirmed.

Others
-We are currently coordinating with the relevant authorities and
departments as to how to secure the cooling water to cool down the
water in the spent nuclear fuel pool of the plant.
-We measured radioactive materials inside of the nuclear power station
area (outdoor) by monitoring car and confirmed that radioactive
materials level is getting higher than ordinary level. As listed below,
we have determined that specific incidents stipulated in article 15,
clause 1(Abnormal increase in radiation dose measured at site boundary)
have occurred.
Determined at 4:17 pm Mar 12th (Around Monitoring Post 4 )*
•Determined at 8:56 am Mar 13th (Around Monitoring Post 4 )
•Determined at 2:15 pm Mar 13th (Around Monitoring Post 4 )
•Determined at 3:50 am Mar 14th (Around Monitoring Post 6 )
•Determined at 4:15 am Mar 14th (Around Monitoring Post 2 )
•Determined at 9:27 am Mar 14th (Around Monitoring Post 3 )
•Determined at 9:37 pm Mar 14th (Around main entrance )
•Determined at 6:51 am Mar 15th (Around main entrance )
•Determined at 8:11 am Mar 15th (Around main entrance )
•Determined at 4:17 pm Mar 15th (Around main entrance )
•Determined at 11:05 pm Mar 15th (Around main entrance )*

-We will continue to make announcements when it was determined that a
specific incident stipulated in article 15, clause 1 has occurred.
-The national government has instructed evacuation for those local
residents within 20km radius of the periphery and evacuation to inside
for those residents from 20km to 30km radius of the periphery, because
it's possible that radioactive materials are discharged.
-Today, at approximately 10am, we observed 400mSv/h at the inland side
of the Unit 3 reactor building and 100mSv/h at the inland side of the
Unit 4 reactor building.
-We will continue to take all measures to restore the security of the
site and to monitor the environment of the site periphery.

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Japanese Earthquake Update (17 March 11:05 UTC)
.by International Atomic Energy Agency (IAEA) on Thursday, March 17, 2011 at 3:25am.Based on a press release from the Japanese Chief Cabinet Secretary dated 17 March 2011 04:00 UTC, the IAEA can confirm that the Japanese military carried out four helicopter water droppings over the building of reactor unit 3 of the Fukushima Daichi nuclear power plant.



According to the press release, the droppings took place between 00:48 UTC and 01:00 UTC.



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UPDATE AS OF 9:00 P.M. EDT, WEDNESDAY, MARCH 16:

Crews began aerial water spraying operations from helicopters to cool reactor 3 at Fukushima Daiichi shortly before 9 p.m. EDT on Wednesday, March 16. The operation was planned for the previous day, but was postponed because of high radiation levels at the plant. News sources said temperatures at reactor 3 were rising. Each helicopter is capable of releasing 7.5 tons of water.

Spokesmen for TEPCO and Japan's regulatory agency, Nuclear and Industry Safety Agency, on March 17 Japan time refuted reports that there was a complete loss of cooling water in the used fuel pool at Fukushima Daiichi reactor 4.

The spokesmen said the situation at reactor 4 has changed little during the day today and water remained in the fuel pool. However, both officials said that the reactor had not been inspected in recent hours.

"We can't get inside to check, but we've been carefully watching the building's environs, and there has not been any particular problem," said TEPCO spokesman Hajime Motojuku.

At about 7 p.m. EDT, NISA spokesman Takumi Koyamada said the temperature reading from the used fuel pool on Wednesday was 84 degrees Celsius and that no change had been reported since then. Typically, used uranium fuel rods are stored in deep water pools at temperatures of about 30 degrees Celsius.

Recent radiation levels measured at the boundary of the Fukushima Daiichi plant have been dropping steadily over the past 12 hours, Japan's Nuclear and Industrial Safety Agency said on Wednesday night (U.S. time).

At 4 a.m. EDT on Wednesday, a radiation level of 75 millirem per hour was recorded at the plant's main gate. At 4 p.m. EDT, the reading at one plant site gate was 34 millirem per hour. By comparison, the Nuclear Regulatory Commission's annual radiation dose limit for the public is 100 millirem. Radiation readings are being taken every 30 minutes.

Japan's Chief Cabinet Secretary, Yukio Edano, said earlier today a radiation level of 33 millirem per hour was measured about 20 kilometers from the Fukushima Daiichi plant earlier this morning. He said that level does not pose an immediate health risk.

Edano said that TEPCO has resumed efforts to spray water into the used fuel pool at the damaged reactor 4.

TEPCO also continues efforts to restore offsite power to the plant, with up to 40 workers seeking to restore electricity to essential plant systems by Thursday morning, March 17.

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Immediate threat is damage of the fuels in the fuel pool outside the containment vessel at uni-3 and unit-4. To improve the situation of lack of water in the spent fuelpools at uni-3 and unit-4, the self defense force started operation for filling the pool with water in 09:48 of March 17. This operation is to drop a huge bucket of seawaterfrom a helicopter. In addition, watering from the ground by high pressure pump is to be prepared.

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Press Release (Mar 17,2011)
Impact to TEPCO's Facilities due to Tohoku-Taiheiyou-Oki Earthquake (as of 10:00AM)


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 apologies 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 to evacuate for those local
residents within 20km radius of the site periphery and to remain indoors
for those local residents between 20km and 30km radius of the site
periphery.

* Unit 1
The explosive sound and white smoke was confirmed near Unit 1 when the big
quake occurred at 3:36pm, March 12th. We have started injection of sea
water at 8:20 pm and then boric acid into the reactor afterwards.

* 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
article 15, clause 1 occurred (failure of reactor cooling function).
At 5:17 pm, 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 is still under operation.

* Unit 3
At 6:50 am, March 14th, while water injection to the reactor was under
operation, 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
has gradually decreased (as of 9:05 am, 490 kPa).

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 are conscious) have sustained injuries and they
were already dispatched 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 works on March 16th was cancelled.

At 6:15 am Today, March 17th, the pressure of the Suppression Chamber
temporally increased, but currently it is stable in a certain range.
Monitoring will be continued.
In order to cool spent fuel pool, water discharge by helicopters has
been conducted today on March 17th with the cooperation of Self-Defense
Force.

* Unit 4
At approximately 6:00 am, March 15th, an explosive sound occurred 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 employee
confirmed that the fire was off.

At approximately 5:45 am, 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.

*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.

* (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
Ohi Thermal Power Station Unit 2: shutdown due to earthquake
Higashi-Ohgishima Thermal Power Station Unit 1: shutdown due to earthquake

[Hydro Power Station]
* All the stations have been restored.

[Transmission System, etc.]
All substation failed due to the earthquake have been restored.

[Blackout in TEPCO's Service Area]
Total of about 2,600 households are out of power (as of 10:00 today).
Tokyo: 0
Kanagawa Pref.: 0
Tochigi Pref.: 0
Chiba Pref.: 0
Saitama Pref: 0
Gunma Pref.: 0
Ibaraki Pref:2,561
Yamanashi Pref: 0
Shizuoka Pref: 0 (east of Fuji River)

[Supply and Demand Status within TEPCO's Service Area to Secure Stable
Power Supply]
Backup supply from Shinshinano Conversion Station: 600MW
Backup supply from Sakuma Conversion Station: 300MW
Backup supply from Higashi Shimizu Conversion Station: 100MW
Backup supply from Kitahon Interconnection Facility: 600MW

Considering the critical balance of our power supply capacity and
expected power demand forward, in order to avoid unexpected blackout,
TEPCO has implemented rolling blackout (planned blackout alternates from
one area to another) since yesterday. 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 drier and to shut down the breaker of distribution
board when you leave your house.
For the customer who has in-house power generation, please secure fuel for
generator.

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Japan Earthquake Update (17 March 2011, 16:55 UTC) - CLARIFIED
Japanese authorities have informed the IAEA that engineers were able have begun to lay an external grid power line cable to Unit 2. The operation was completed at 08:30 UTC. The operation was continuing as of 20:30 UTC, Tokyo Electric Power Company officials told the Nuclear and Industrial Safety Agency.

They plan to reconnect power to Unit 2 once the spraying of water on the Unit 3 reactor building is completed.

The spraying of water on the Unit 3 reactor building was temporarily stopped at 11:09 UTC (20:09 local time) of 17 March.*

The IAEA continues to liaise with the Japanese authorities and is monitoring the situation as it evolves.

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Cooling spent fuel pools
•On Unit 3, water discharge by Self-Defense Force's helicopters had been
conducted since 9:48 AM in the morning on March 17th.
•On Unit 3, water discharge by the riot police's high-pressure water
cannon trucks and Self-Defense Force's fire engines had been conducted
since approximately past 7PM on March 17th and they had finished water
discharge at 8:09PM.
•We are considering further water discharge at Unit 3 and others subject
to the conditions of spent fuel pools when we get ready.

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http://www.iaea.org/newscenter/news/2011/tsunamiupdate01.html

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Japan Earthquake Update (18 March 2011, 06:10 UTC)
Temperature of Spent Fuel Pools at Fukushima Daiichi Nuclear Power Plant - UPDATED

Spent fuel removed from a nuclear reactor is highly radioactive and generates intense heat. Nuclear plant operators typically store this material in pools of water that cool the fuel and shield the radioactivity. Water in a spent fuel pool is continuously cooled to remove heat produced by spent fuel assemblies. According to IAEA experts, a typical spent fuel pool temperature is kept below 25 °C under normal operating conditions. The temperature of a spent fuel pool is maintained by constant cooling, which requires a constant power source.

Given the intense heat and radiation that spent fuel assemblies can generate, spent fuel pools must be constantly checked for water level and temperature. If fuel is no longer covered by water or temperatures reach a boiling point, fuel can become exposed and create a risk of radioactive release. The concern about the spent fuel pools at Fukushima Daiichi is that sources of power to cool the pools have been compromised.

Concern about spent fuel storage conditions has led Japanese officials to drop and spray water from helicopters and trucks onto Unit 3 at Fukushima Daiichi nuclear power plant (See earlier update).

Japan's Nuclear and Industrial Safety Agency has reported increasing temperatures in the spent fuel ponds at Units 5 and 6 since 14 March. An emergency diesel generator at Unit 6 is now powering water injection into the ponds at those Units, according to NISA.[/B
]The IAEA can confirm the following new information regarding the temperatures of the spent nuclear fuel pools at Units 4, 5 and 6 at Fukushima Daiichi nuclear power plant:


13 March, 19:08 UTC: 84 °C
Unit 5
17 March, 03:00 UTC: 64.2 °C
17 March, 18:00 UTC: 65.5 °C
Unit 6
17 March, 03:00 UTC: 62.5 °C
17 March, 18:00 UTC: 62.0 °C

The IAEA is continuing to seek further information about the water levels, temperature and condition of all spent fuel pool facilities at the Fukushima Daiichi nuclear power plant.

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All 6 units of Fukushima Daiichi Nuclear Power Station have been shut down.


Unit 1(Shut down)
- Reactor has been shut down. However, the explosive sound and white smoke
were confirmed after the big quake occurred at 3:36PM Mar 12th. It was
assumed to be hydrogen explosion.
- We have been injecting sea water into the reactor pressure vessel.

Unit 2(Shut down)
- Reactor has been shut down and Reactor Core Isolation Cooling System has
been injecting water to the reactor. However, the level of reactor
coolant had dropped and the reactor pressure had increased because
the system stopped. The national government instructed that measures are
taken to lower the pressure within the Reactor Containment Vessel and
to inject sea water into the Reactor while carefully confirming safety.
The level of reactor coolant and the pressure of the Reactor had resumed.
- At approximately 6:00AM on March 15, 2011, an abnormal noise began
emanating from nearby Pressure Suppression Chamber and the pressure
within this chamber decreased.
- While we continue sea water injection operations, we temporarily moved
TEPCO employees and workers from other companies not directly involved
in this work to safe places.

Unit 3(Shut down)
- Reactor has been shut down. However, the explosive sound and white smoke
were confirmed at 11:01AM Mar 14th. It was assumed to be hydrogen explosion.
- Fog like steam was confirmed from the reactor building at 8:30AM on
March 16th,
- We continue monitoring as it was reported that the pressure of
the Suppression Chamber has been temporarily increasing since
approximately 6:15AM on March 17th.
- We have been injecting sea water into the reactor pressure vessel.

Unit 4 (outage due to regular inspection)
- Reactor has been shut down. However, at approximately 6AM on March 15th.
we have confirmed the explosive sound and the sustained damage around
the 5th floor rooftop area of the Nuclear Reactor Building.
- On March 15th and 16th, we respectively confirmed the outbreak of fire
at the 4th floor of the northwestern part of the Nuclear Reactor
Building. We immediately reported this matter to the fire department and
the related authorities. TEPCO employees confirmed that each fire had
already died down by itself. We will continue to carefully monitor
situations.
- Currently, we do not consider any reactor coolant leakage inside
the reactor containment vessel.

Unit 5 (outage due to regular inspection)
- Reactor has been shut down and the sufficient level of reactor coolant
to ensure safety is maintained.
- Currently, we do not consider any reactor coolant leakage inside
the reactor containment vessel.

Unit 6 (outage due to regular inspection)
- Reactor has been shut down and the sufficient level of reactor coolant
to ensure safety is maintained.
- Currently, we do not consider any reactor coolant leakage inside
the reactor containment vessel.

Cooling spent fuel pools
•On Unit 3, water discharge by Self-Defense Force's helicopters had been
conducted since 9:48 AM in the morning on March 17th.
•On Unit 3, water discharge by the riot police's high-pressure water
cannon trucks and Self-Defense Force's fire engines had been conducted
since approximately past 7PM on March 17th and they had finished water
discharge at 8:09PM.
•We are considering further water discharge at Unit 3 and others subject
to the conditions of spent fuel pools when we get ready.

Casualty
- 2 workers of cooperative firm were injured at the occurrence of
the earthquake, and were transported to the hospital.
- 1 TEPCO employee who was not able to stand by his own holding left chest
with his hand, was transported to the hospital by an ambulance.
- 1 subcontract worker at the key earthquake-proof building was
unconscious and transported to the hospital by an ambulance.
- The radiation exposure of 1 TEPCO employee, who was working inside
the reactor building, exceeded 100mSv and he was transported to
the hospital.
- 2 TEPCO employees felt bad during their operation in the central control
rooms of Unit 1 and 2 while wearing full masks, and were transferred
to Fukushima Daini Power Station for consultation with a medical advisor.
- 4 workers were injured and transported to the hospital after explosive
sound and white smoke were confirmed around the Unit 1.
- 11 workers were injured and transported to Fukushima Daini Nuclear Power
Station etc. after explosive sound and white smoke were confirmed around
the Unit 3.One of the workers was transported to the FUKUSHIMA Medical
University Hospital at 10:56AM
- Presence of 2 TEPCO employees at the site is not confirmed.

Others
- We measured radioactive materials (iodine etc.) inside of the nuclear
power station area (outdoor) by monitoring car and confirmed that
radioactive materials level is getting higher than ordinary level.
As listed below, we have determined that specific incidents stipulated
in article 15, clause 1 of Act on Special Measures Concerning Nuclear
Emergency Preparedness (Abnormal increase in radiation dose measured
at site boundary) have occurred.
•Determined at 4:17 PM Mar 12th (Around Monitoring Post 4 )
•Determined at 8:56 AM Mar 13th (Around Monitoring Post 4 )
•Determined at 2:15 PM Mar 13th (Around Monitoring Post 4 )
•Determined at 3:50 AM Mar 14th (Around Monitoring Post 6 )
•Determined at 4:15 AM Mar 14th (Around Monitoring Post 2 )
•Determined at 9:27 AM Mar 14th (Around Monitoring Post 3 )
•Determined at 9:37 PM Mar 14th (Around main entrance )
•Determined at 6:51 AM Mar 15th (Around main entrance )
•Determined at 8:11 AM Mar 15th (Around main entrance )
•Determined at 4:17 PM Mar 15th (Around main entrance )
•Determined at 11:05 PM Mar 15th (Around main entrance )

- The national government has instructed evacuation for those local
residents within 20km radius of the periphery and evacuation to inside
for those residents from 20km to 30km radius of the periphery, because
it's possible that radioactive materials are discharged.
- At approximately 10AM on March 15, we observed 400mSv/h at the inland
side of the Unit 3 reactor building and 100mSv/h at the inland side of
the Unit 4 reactor building.
- We will continue to take all measures to ensure the safety and to
continue monitoring the surrounding environment aroud the Power Station.

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UPDATE AS OF 10:20 P.M. EDT, THURSDAY, MARCH 17:

TEPCO continues to install cables, transformers and distribution equipment to restore offsite grid power to Fukushima Daiichi reactors 1 and 2. Reactor 1 has now been included in the power restoration plan.

Chief Cabinet Secretary Edano said in a recent conference that plans are in place to use 30 water cannon trucks and fire engines to spray water into the reactor 3 spent fuel pool, and TEPCO is discussing whether to do the same for the reactor 1 spent fuel pool. The spraying work is to be done in the next few hours, after the cable work is completed.


UPDATE 10:00 P.M. EDT, THURSDAY, MARCH 17:

NEI held a conference call on the morning of March 17, to update media on the latest actions by the U.S. nuclear energy industry in light of events in Japan. The audio of this conference call can be found on NEI's YouTube channel.


UPDATE AS OF 9:15 P.M. EDT, THURSDAY, MARCH 17:

Tokyo Electric Power Co. said it hopes to activate the cooling system for Fukushima Daiichi reactor 2 "as early as Friday night" (Japan time). The company said it could restore power from the electric grid to reactor 2 by Thursday night (U.S. time).

The International Atomic Energy Agency reported that TEPCO completed connecting electrical cable from a makeshift transformer to reactor 2 at 4:30 A.M. EDT. Engineers were waiting to complete spraying sea water into the reactor 3 fuel pool before they restore power through the cable to the reactor 2 cooling system.

TEPCO says that if it can provide power supply to the other reactors, it could begin restoring some cooling functions. The company said that after fire trucks injected water into reactor 3's fuel pool, radiation levels at the plant's west gate dropped from 31 millirem per hour to 29 millirem per hour at 10:00 A.M. EDT.


UPDATE AS OF 5:45 P.M. EDT, THURSDAY, MARCH 17:

NEI has uploaded three new videos to its YouTube channel. The first features Art Stall (Retired), President and Chief Nuclear Officer of NextEra Energy, discussing how the U.S. nuclear industry prepares for natural and man-made disasters. The second and third videos feature Jeff Merrifield, former NRC commissioner and senior vice president at The Shaw Group, discussing next steps for implementing lessons learned from Japan and confidence that construction of new U.S. nuclear plants should continue.

UPDATE AS OF 5:00 P.M. EDT, THURSDAY, MARCH 17:

It is unlikely that radiation released from the nuclear reactors in Japan will harm anyone in the United States, President Obama said in a press briefing this afternoon.

"We do not expect harmful levels of radiation to reach the United States, Hawaii, Alaska or U.S. territories in the Pacific," Obama said. He added that the Centers for Disease Control and Prevention "does not recommend that people in the U.S. take precautionary measures other than staying informed."

Obama said "our nuclear plants have undergone exhaustive study and have been declared safe for any number of contingencies." However, he said that when there is an event such as the Fukushima accident, "we should learn from that. That's why I have asked the NRC to do a comprehensive review of our nuclear plants" in light of the natural disaster that has happened in Japan.

In a briefing earlier on Thursday, Gregory Jaczko, chairman of the U.S. Nuclear Regulatory Commission, said, "There can't be any harm to anyone in the United States" from the Japanese nuclear power plant.

Dan Poneman, the deputy secretary of energy, said today that two U.S. flights to Japan collected information on radiation levels. These readings informed the decision to recommend that Americans evacuate an area 50 miles from the Fukushima Daiichi nuclear energy facility.

Poneman expressed confidence in the safety of U.S. nuclear power plants, saying they're evaluated on a "minute by minute" basis. Taking safety precautions "goes back decades," he said. Tough safety standards have been in effect and upgraded since 1979, he said.

***Edited to add, by me, all the Fukushima plants were built prior to 1979 (Three Mile Island) and there have been complaints over the years that upgrades for safety were not sufficient.***

Status of Fukushima plants

In Japan, engineers have laid a power line that can connect reactor 2 of the Daiichi facility to the off-site power grid, the International Atomic Energy Agency reported. Workers are working to reconnect the power to reactor 2 after they complete spraying water into the reactor 3 complex to provide additional cooling to the used fuel pool. Reconnecting to the power grid is expected to enhance efforts to prevent further damage at the plant.

Japan's Nuclear and Industrial Safety Agency reported on Thursday that the backup diesel generator for reactor 6 is working and supplying electricity to reactors 5 and 6. TEPCO is preparing to add water to the storage pools that house used nuclear fuel rods at those two reactors.


UPDATE AS OF 1:30 P.M. EDT, THURSDAY, MARCH 17:

Radiation readings at the Fukushima Daiichi site boundary were measured today at a lower level, between 2 and 3 millirem per hour.

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UPDATE AS OF 11:35 A.M. EDT, THURSDAY, MARCH 17:

Fukushima Daiichi
The reactors at the Fukushima Daiichi plant are in stable condition and are being cooled with seawater, but workers at the plant continue efforts to add cooling water to fuel pools at reactors 3 and 4.

The status of the reactors at the site is as follows:

Reactor 1's primary containment is believed to be intact and the reactor is in a stable condition. Seawater injection into the reactor is continuing.

Reactor 2 is in stable condition with seawater injection continuing. The reactor's primary containment may not have been breached, Tokyo Electric Power Co. and World Association of Nuclear Operators officials said on Thursday.

Access problems at the site have delayed connection of a temporary cable to restore off-site electricity. The connection will provide power to the control rod drive pump, instrumentation, batteries and the control room. Power has not been available at the site since the earthquake on March 11.

Reactor 3 is in stable condition with seawater injection continuing. The primary containment is believed to be intact. Pressure in the containment has fluctuated due to venting of the reactor containment structure.

TEPCO officials say that although one side of the concrete wall of the reactor 4 fuel pool structure has collapsed, the steel liner of the pool remains intact, based on aerial photos of the reactor taken on March 17. The pool still has water providing some cooling for the fuel; however, helicopters dropped water on the reactor four times during the morning (Japan time) on March 17. Water also was sprayed at reactor 4 using high-pressure water cannons.

Reactors 5 and 6 were both shut down before the quake occurred. Primary and secondary containments are intact at both reactors. Temperature instruments in the spent fuel pools at reactors 5 and 6 are operational, and temperatures are being maintained at about 62 degrees Celsius. TEPCO is continuing efforts to restore power at reactor 5.

Fukushima Daini
All four reactors at the Fukushima Daini plant have reached cold shutdown conditions with normal cooling being maintained using residual heat removal systems.

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Unit-1, 2, 3 & 4, which were in full operation when the earthquake occurred,
all shutdown automatically.External power supply was available after the quake.
While injecting water into the reactor pressure vessel using make-upwater system,
TEPCO recovered the core cooling function and made the unit into cold shutdown state one by one.
Latest Monitor Indication: 15.9 μSv/h at 12:00, Mar. 17 at NPS borderEvacuation Area: 10km from NPS
[Significance judged by JAIF]

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The average person in the United States receives about 360 mrem every year whole body equivalent dose. This is mostly from natural sources of radiation, such as radon. (See Radiation and Us ).

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other way of looking at risk, is to look at the Relative Risk of 1 in a million chances of dying of activities common to our society.


Smoking 1.4 cigarettes (lung cancer)
Eating 40 tablespoons of peanut butter
Spending 2 days in New York City (air pollution)
Driving 40 miles in a car (accident)
Flying 2500 miles in a jet (accident)
Canoeing for 6 minutes
Receiving 10 mrem of radiation (cancer)

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As context, radiation levels in the aftermath of the Chernobyl accident were 1 millirem per year in the United States and in Canada. By comparison, each person receives the same radiation dose from watching television over a year’s time. Among countries neighboring the site of the Chernobyl accident, Bulgaria received the highest radiation dose at 76 millirem per year, followed by Austria at 68 millirem per year, Greece at 59 millirem per year, and Finland at 45. The U.S. Nuclear Regulatory Commission’s annual public radiation limit is 100 millirem.

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