Japanese Earthquake, Tsunami, and Nuclear Reactors | Golden Skate

Japanese Earthquake, Tsunami, and Nuclear Reactors

dorispulaski

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dorispulaski

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Current IAEA status

.Japan’s Nuclear and Industrial Safety Agency (NISA) has provided the IAEA with further information about the hydrogen explosion that occurred today at the unit 3 reactor at the Fukushima Daiichi nuclear plant. A hydrogen explosion occurred at unit 3 on 14 March at 11:01AM local Japan time.

All personnel at the site are accounted for. Six people have been injured.

The reactor building exploded but the primary containment vessel was not damaged. The control room of unit 3 remains operational.

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

There are other reports that 11 people were injured, no one killed.

The difference between Daiichi and Daiina is that Daiina has external power. Daiichi's backup diesel generation capacity was wiped out by the tsunami.

As to how much radiation was released during this explosion, it should be similar to that released during the hydrogen explosion at Reactor 1:

The highest recorded radiation level at the Fukushima Daiichi site was 155.7 millirem at 1:52 p.m. EDT on March 13. Radiation levels were reduced to 4.4 millirem by the evening of March 13. The Nuclear Regulatory Commission’s radiation dose limit for the public is 100 millirem per year.
 
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dorispulaski

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This was fairly recently posted.

Press Conference by the Chief Cabinet Secretary




Monday, March 14 at 11:00am, 2011
[Provisional Translation]
JAPANESE


CHIEF CABINET SECRETARY EDANO: Since yesterday, we have been continually injecting sea water into the reactor core of the Unit 3 reactor at the TEPCO Fukushima Daiichi Nuclear Power Station. A short time ago, at 11:01, an explosion occurred in the Unit 3 reactor. Based on the conditions of the explosion and other factors, we believe that this explosion was similar in kind to the hydrogen explosion that occurred in the Unit 1 reactor.

I have been in direct contact with the director of the power station to confirm the situation. As the specialist closest to the scene, the station director has reported that as of approximately 11:30 today, the condition of the containment vessel remains sound. Consequently, we believe that the risk that large amounts of radioactive materials have been dispersed is low.

However, we expect an increase in radiation levels similar to the one that followed the hydrogen explosion that occurred in the Unit 1 reactor. Accordingly, I have given instructions to the very small number of people who were in the process of evacuating from a 20km zone around the power station that they should take refuge indoors immediately as a precautionary measure.

At the present time, we are receiving data that the pressure inside the reactor vessel is stable and that the supply of water is continuing. This information, if reliable, would support the station director's on-the-scene appraisal of the situation.

At the moment we are devoting our energies to gathering information and data on radiation density and other conditions in the vicinity of the site. If you don't mind, I would now like to return to collecting and analyzing the latest information.

I have also heard that the team at Daiini has gotten Reactor 2 into cold shutdown, as is Reactor 4. I hope this is true.
 

dorispulaski

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Here's the status of the four Daiini Reactors (the facility that retained external power, but was still reported as at an emergency status. Relatively goodness in a bad situation.
Unit 3 is in cold shutdown.
Unit 1 & 2 are now cooling, as all the cooling system work is complete
Unit 4: Work is still in progress to the cooling system.
Radiation measurements outside the facility are still normal. As this plant is only 10 km from Daiichi, that is not bad news.

http://www.tepco.co.jp/en/press/corp-com/release/11031404-e.html

Unit 1 (shut down at 2:48pm on March 11th)
- Reactor is shut down and reactor water level is stable.
- Offsite power is available.
- At 8:19am, Mar 12th, there was an alarm indicating that one of the
control rods was not properly inserted, however, at 10:43am, Mar 12th
the alarm was spontaneously called off. Other control rods has been
confirmed that they are fully inserted (reactor is in subcritical
status)
- Status of main steam isolation valve: closed
- Injection of water into the reactor is done by Make-up Water Condensate
System.
- We do not believe there is leakage of reactor coolant in the containment
vessel at this moment.
- At 5:22am, Mar 12th, the temperature of the suppression chamber exceeded
100 degrees. As the reactor pressure suppression function was lost, at
5:22am, Mar 12th, it was determined that a specific incident stipulated
in article 15, clause 1 has occurred.
- We decided to prepare implementing measures to reduce the pressure of
the reactor containment vessel (partial discharge of air containing
radioactive materials) in order to fully secure safety. This preparation
work started at around 9:43am, Mar 12th and finished at 6:30pm, Mar 12th.
- Restoration work in reactor cooling function that was conducted to
achieve reactor cold shutdown has been completed and cooling of the
reactor has been commenced at 1:24 am, Mar 14th.

Unit 2 (shut down at 2:48pm on March 11th)
- Reactor is shut down and reactor water level is stable.
- Offsite power is available.
- Control rods are fully inserted (reactor is in subcritical status)
- Status of main steam isolation valve: closed
- Injection of water into the reactor is done by Make-up Water Condensate
System.
- We do not believe there is leakage of reactor coolant in the containment
vessel.
- At 5:32am, Mar 12th, the temperature of the suppression chamber exceeded
100 degrees. As the reactor pressure suppression function was lost,
at 5:32am, Mar 12th, it was determined that a specific incident
stipulated in article 15, clause 1 has occurred.
- We decided to prepare implementing measures to reduce the pressure of
the reactor containment vessel (partial discharge of air containing
radioactive materials) in order to fully secure safety. This preparation
work started at around 10:33am, Mar 12th and finished at 10:58pm, Mar
12th.
- Restoration work in reactor cooling function is in progress to achieve
reactor cold shutdown.
- Restoration work in reactor cooling function that was conducted to
achieve reactor cold shutdown has been completed and cooling of the
reactor has been commenced at 7:13 am, Mar 14th.

Unit 3 (shut down at 2:48pm on March 11th)
- Reactor is shut down and reactor water level is stable.
- Offsite power is available.
- Control rods are fully inserted (reactor is in subcritical status)
- Status of main steam isolation valve: closed
- We do not believe there is leakage of reactor coolant in the containment
vessel.
- We decided to prepare implementing measures to reduce the pressure of
the reactor containment vessel (partial discharge of air containing
radioactive materials) in order to fully secure safety. The preparation
woke started at around 12:08pm, Mar 12th and finished at 12:13pm, Mar
12th.
- Reactor cold shutdown at 12:15pm, Mar 12th

Unit 4 (shut down at 2:48pm on March 11th)
- Reactor is shut down and reactor water level is stable.
- Offsite power is available.
- At 0:43PM, there was a signal indicating that one of the control rods
may have not properly inserted. However, we confirmed that it was
inserted completely by another signal. We will inspect the reason of
this.
- Status of main steam isolation valve: closed
- Injection of water into the reactor is done by Make-up Water Condensate
System.
- We do not believe there is leakage of reactor coolant in the containment
vessel.
- In order to cool down the reactor, injection of water into the reactor
had been done by the Reactor Core Isolation Cooling System, however,
At 6:07am, Mar 12th, the temperature of the suppression chamber exceeded
100 degrees. As the reactor pressure suppression function was lost, at
6:07am, Mar 12th, it was determined that a specific incident stipulated
in article 15, clause 1 has occurred.
- We decided to prepare implementing measures to reduce the pressure of
the reactor containment vessel (partial discharge of air containing
radioactive materials) in order to fully secure safety. The preparation
woke started at around 11:44am, Mar 12th and finished at around 11:52am,
Mar 12th.
- Restoration work in reactor cooling function is in progress to achieve
reactor cold shutdown.

Indication from monitoring posts installed at the site boundary did not
show any difference from ordinary level.
No radiation impact to the external environment has been confirmed. We
will continue to monitor in detail the possibility of radioactive material
being discharged from exhaust stack or discharge canal.
 

dorispulaski

Wicked Yankee Girl
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Status of the Daiichi Reactors.

My concern would be that Daiichi 2 is now going the way of Daiichi 1 and Daiichi 3.
I see no reason that it would be different, unless external power could be restored.

As long as the containment vessels remain intact, release of nuclear materials will be relatively limited. We used to have huge, movable diesel generators on semis at IBM. I wonder that they do not have the same-perhaps the roads are in too bad shape to move such things to Daiichi.

The IAEA says that Japan has now asked for their assistance.

www.facebook.com/iaeaorg

http://www.tepco.co.jp/en/press/corp-com/release/11031405-e.html
Press Release (Mar 14,2011)
White smoke around the Fukushima Daiichi Nuclear Power Station Unit 3 (3rd release)


At approximately 11:01am, an explosion followed by white smoke occurred
at the reactor building of Unit 3. It was believed to be a hydrogen
explosion.

According to the parameter, it is believed that the reactor containment
vessel remains intact. However, the status of the plant and the impact
of radioactive materials to the outside environment are presently under
investigation. (previously announced)

As of 1:30 pm, 4 TEPCO employees and 3 workers from other companies have
sustained injuries (all of them are conscious). 3 ambulances are in
operation to care for them and 2 have already dispatched the casualties
to the hospital.

As of 0:30 pm, the measured value of radiation dose near MP6 was 4μSv/h.
The increase of the radiation dose cannot be confirmed at this time.

As of 0:30 pm, the measured value of radiation dose at the monitoring
post in Fukushima Daini Power Station located approximately 10 km south
of Fukushima Daiichi Power Station remains at the same level.

In light of the incidents that have occurred at Units 1 and 3, we are
considering applying prevention measures to the wall of the reactor
building to ventilate the hydrogen gas contained in Unit 2.

TEPCO continues to take all measures to restore the safety and security
of the site and are monitoring the site's immediate surroundings.
 
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76olympics

On the Ice
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Mar 4, 2004
The language is so hyperbolic on MSNBC that I expect to see the Four Horsemen riding across the screen shortly. Thanks for your fact-based updates, Doris Pulaski. There are some comments on the story at MSNBC that seem to be written by people with real technical knowledge versus the "Oh NOOOO!" and "I hope."

I am sure that we don't/can't know everything- that would be impossible even is our all news/all the time era, but I feel that qualified people are assuredly on the scene.

The earthquake and flood damage are probably preoccupying the residents now. I donated towards that relief, but I know it is only a drop in an acean..
 

mot

On the Ice
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Feb 17, 2010
The language is so hyperbolic on MSNBC that I expect to see the Four Horsemen riding across the screen shortly. Thanks for your fact-based updates, Doris Pulaski. There are some comments on the story at MSNBC that seem to be written by people with real technical knowledge versus the "Oh NOOOO!" and "I hope."

I am sure that we don't/can't know everything- that would be impossible even is our all news/all the time era, but I feel that qualified people are assuredly on the scene.

The earthquake and flood damage are probably preoccupying the residents now. I donated towards that relief, but I know it is only a drop in an acean..

I increasingly find BBC is not that much better than their American counterparts too. For example, they said 'there are a few different opinions on what actually caused the explosion of the Fukushima Dai'ichi's 3rd reactor, but the official line of explanation is that it was caused by hydrogen collected at the top of the most external housing reacting with oxygen' - implying the the official explanation by the Tokyo Electricity might be deceiving, but fail to clarify what are the different opinions. I think it is bordering scaremongering.

I also would like to thank Doris for updating us with the information provided by the IAEA. I would never thought that I'd come to Golden Skate for the latest and trustworthy information about the status of nuclear reactors in my own country!
 

dorispulaski

Wicked Yankee Girl
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Back in the day, I was a physicist, so nuclear power is an interest of mine.

More from the IAEA
This might provide an explanation for why there was a second build up of hydrogen, with a second explosion in Unit 3. Yesterday, they had a problem with the sea water reservoir and stopped pumping the sea water into the 3 reactors. It's not clear from the press release what the problem was, but as surely as they stopped pumping in seawater, the temperature in the reactor would rise. However, today they have been able to resume cooling with sea water. My understanding is that fire trucks are doing the pumping, but I am not sure if that is true, nor do I know why there would have been a problem:

Fukushima Daiichi Nuclear Power Plant

Japanese authorities have reported to the IAEA that Fukushima Daiichi Unit 2 has experienced decreasing coolant levels in the reactor core. Officials have begun to inject sea water into the reactor to maintain cooling of the reactor core.

Sea water injections into Units 1 and 3 were interrupted yesterday due to a low level in a sea water supply reservoir, but sea water injections have now been restored at both units.

The IAEA also reports that roughly 185,000 people have been evacuated from towns around Daiichi and Daiina (as far as I can tell, this is in response to the order to evacuate. First you order, but you count when the people arrive at the temporary areas), and that while iodine pills have been distributed to all of them in the shelters they have been relocated to, they have not been directed to take the pills. To me, this means that the release of radiation has not yet been large enough for there to be a significant risk of developing thyroid cancer, in the view of the Japanese government, the IAEA, and TEPCO, all of whom are involved.

The IAEA is also reporting the weather, and the best news is that the wind has been blowing from Japan towards the ocean at Daiichi, and that weather pattern is expected to continue for the next 3 days.

The IAEA is giving formal daily updates to UN member nations on the situation, now that the Japanese government has requested their help.
 

dorispulaski

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More from NEI, the nuclear industry people-this is an older version than the last TEPCO update, which reported 2 units at Daiini were cooling properly, one in cold shutdown, and one still being worked on. However, it does give some insight into what went wrong in Daiichi Reactor 2 yesterday (in addition to low levels of sea water in the sea water reservoir).

UPDATE AS OF 1:30 P.M. EDT, MONDAY, MARCH 14:
Unit 2 at the Fukushima Daiichi nuclear power plant lost a significant amount of reactor coolant for a second time on Monday. Some of the uranium fuel rods were uncovered for a period of time. A malfunctioning safety relief valve at the plant caused an increase in reactor pressure and hindered injection of coolant back into the reactor. The cause of the relief valve failure is under investigation.

The Japanese government has distributed 230,000 units of potassium iodine to evacuation centers in the area surrounding the Fukushima Daiichi and Fukushima Daini stations, according to officials. Ingestion of potassium iodine can help prevent the accumulation of radioactive iodine in the thyroid.

At the Fukushima Daini site all units have off-site power, and water levels in all units are stable. Plant operators at Daini Unit 1 were able to restore a residual heat remover system, which is now being used to cool the reactor. Work is in progress to achieve a cold shutdown. Workers at Daini Units 2 and 4 are working to restore residual heat removal systems. Unit 3 is in a safe, cold shutdown.

Radiation dose rate measurements observed at four locations around the Daini plant´s perimeter over a 16-hour period on Sunday were all normal.
 

dorispulaski

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The NEI (nuclear industry organization) has published a document about what levels of exposure to radioactive materials and radiation actually means for a normal member of the public:

http://www.nei.org/newsandevents/in...ctors-in-that-region/radiation-in-perspective

This document is explicitly for dissemination to the general public, so I'm quoting it here in its entirety:

Millirem
The unit of measurement of the amount of radiation received by a person (“radiation dose”) is a millirem. This is similar to the units of inch (for length), ounce (for weight), and degree (for temperature).


Natural Background Radiation
On average, Americans receive about 310 millirem per year of radiation dose from naturally-occurring radiation in the environment (commonly known as “natural background radiation”). This includes radiation from space (cosmic radiation), and radioactive material in the earth, the air, and food and water.


Radon in home and workplaces accounts for 2/3 of natural background radiation dose (about 200 millirem per year).
A round trip flight between New York and Los Angeles will result in 4 millirem due to being at a higher altitude and receiving more cosmic radiation.
Flight crews receive 200-400 millirem per year.

Medical and Dental Radiation
Americans also receive a radiation dose from medical and dental procedures in the form of x-rays, CT scans, nuclear medicine, etc. Although the average amount of radiation dose is calculated as more than 300 millirem per year, much larger amounts of radiation dose are received by people undergoing diagnosis or treatment of specific medical conditions.


A typical chest x-ray is 2 millirem.
An upper GI tract examination is 600 millirem.
A CT scan of the chest or abdomen is 800 millirem.

Federal Radiation Safety Limits
Federal agencies such as the Nuclear Regulatory Commission (NRC) establish radiation dose limits to protect the health and safety of the public and nuclear workers. The limits are based on the current scientific understanding of potential risks from radiation exposure.

The NRC radiation dose limit for protecting members of the public is 100 millirem per year.
The NRC radiation dose limit for protecting nuclear workers is 5,000 millirem per year.

Radiation from a Nuclear Power Plant – Routine Operations
As a part of routine operations, small amounts of radioactive material are released from nuclear power plants into the environment in accordance with requirements that are specified in the operating licenses issued by the NRC. Radiation dose to members of the public from these releases into the air and water are routinely monitored by the plants, the states and the NRC and are documented in public reports submitted to the NRC. The average radiation dose to a person living near a nuclear power plant is much less than 1 millirem per year.


Radiation from a Nuclear Power Plant – Accident
Under accident conditions at a nuclear power plant, involving fuel damage or melting, radioactive fission products are released from the fuel elements into water and steam surrounding the fuel within the reactor vessel. Primary fission products include radioactive noble gases (krypton and xenon), iodine and cesium, and to a lesser extent, strontium. As pressure and temperature build up in the reactor, the safety relief valves release the steam into the suppression pool in the torus (BWR design)*. Among other functions, the suppression pool helps to cool and trap the majority of cesium, iodine, strontium in the suppression pool water. Periodic venting from the suppression pool may be conducted to manage temperature and pressure and protect the integrity of the primary containment.

Releases to the environment associated with venting consist primarily of radioactive noble gases which, by their chemical and physical nature, disperse in the atmosphere and provide a source of radiation exposure in a passing plume or vapor cloud. The current conditions at the Fukushima Daiichi plant may result in a reduced effectiveness in trapping the radioactive cesium and iodine in the suppression pool. Therefore, the releases may contain higher levels of radioactive cesium and iodine, which provide sources of exposure from inhalation and ingestion.

Specific information on key radionuclides is as follows:


Krypton-85 –radioactive noble gas; beta-gamma emitter; 11 year half-life.
Xenon-133 –radioactive noble gas; beta-gamma radiation emitter; 5 day half-life
Cesium-137 –radioactive form of cesium; beta-gamma radiation emitter; 30 year half-life
Iodine-131 –radioactive form of iodine that concentrates in the thyroid gland; beta-gamma radiation emitter; 8 day half-life
Strontium 90 –radioactive form of strontium; beta radiation emitter; 29 year half-life

*The Daiichi reactors, are AFAIR, of the BWR (Boiling Water Reactor) design, produced by GE.
 

dorispulaski

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The NEI, the US nuclear industry source, has issued the following update. I have not yet seen an update from Tokyo Electric, nor the IAEA. This is bad news:


UPDATE AS OF 9:40 P.M. EDT, MONDAY, MARCH 14:
An explosion in the vicinity of the suppression pool at Fukushima Daiichi 2 just after 6:20 a.m. Japan Standard Time (5:20 p.m. EDT) may have damaged a portion of the reactor’s primary containment structure.

Pressure in the suppression pool has been reported to have decreased to ambient atmospheric pressure shortly after the blast. Plant operator Tokyo Electric Power Co. (TEPCO) has reported possible damage to the reactor’s pressure-suppression system. Radiation levels at local monitoring stations have risen but are still in flux. TEPCO has evacuated some workers from all three Fukushima reactors with the exception of approximately 50 workers involved in sea water pumping activities into the reactors as part of emergency cooling efforts.

Residents within a 20-kilometer (12.5 mile) zone around the plant were ordered to evacuate on Saturday following a hydrogen explosion at Unit 1. Another hydrogen explosion occurred this morning (U.S. time) at Unit 3.

Efforts to inject sea water into Unit 2 have been complicated by a faulty pressure relief valve. The fuel at Unit 2 has been exposed at least twice, before being re-covered with sea water.

Japan's Chief Cabinet Secretary, Yukio Edano, has said a partial defect has been found inside the containment vessel of reactor 2 at the Fukushima Daiichi nuclear power plant.


UPDATE AS OF 5:30 P.M. EDT, MONDAY, MARCH 14:
Tokyo Electric Power Co. reported at 3:00 p.m. EDT that work had resumed to pump seawater into Fukushima Daiichi 2 to maintain safe cooling water levels after the utility was able to vent steam from the pressure vessel. The fuel had been exposed for 140 minutes Monday night due to a malfunctioning pressure relief valve. Water levels later went up to cover more than half of the rods.

The U.S. Nuclear Regulatory Commission reports that the Japanese government has formally asked for assistance from the United States on nuclear power plant cooling issues triggered by the March 11 tsunami.

The agency has already sent two experts on boiling water reactor issues to Japan as part of a U.S. Agency for International Development disaster relief team. The experts now are in Tokyo providing technical assistance. The U.S. NRC is also monitoring the Japanese reactor events around the clock from its headquarters operations center in Rockville, Md.

Prior to the second exposure of the rods around 11 p.m., March 14 local time in Japan, radiation at the plant site was detected at a level twice the maximum seen so far – 313 millirem per hour, according to TEPCO.

Chief Cabinet Secretary Yukio Edano said he believes the problem at the plant ''will not develop into a situation similar to Chernobyl,” even in the worst case.

The utility said a hydrogen explosion at the nearby No. 3 reactor that occurred Monday morning may have caused a glitch in the cooling system of the No. 2 reactor.

The hydrogen explosion at reactor 3 on March 14 injured 11 people: seven TEPCO workers at the site and four members of the country’s Self-Defense Forces. The reactor's containment vessel was not damaged and the reactor remains safely contained in its primary containment.
 

dorispulaski

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IAEA update on Daiini. 3 units now in cold shutdown. Information on Unit 4 just added.

Japan Earthquake Update (15 March 2011, 03:35 CET)
.by International Atomic Energy Agency (IAEA) on Monday, March 14, 2011 at 8:15pm.Japanese authorities yesterday reported to the IAEA at 21:05 CET that the reactors Units 1, 2 and 3 of the Fukushima Daini nuclear power plant are in cold shutdown status. This means that the pressure of the water coolant is at around atmospheric level and the temperature is below 100 degrees Celsius. Under these conditions, the reactors are considered to be safely under control...

Japanese authorities have also informed the IAEA that teams of experts from Tokyo Electric Power Company (TEPCO), the plant´s operator, are working to restore cooling in the reactor Unit 4 and bring it to cold shutdown.

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

.

The statement about Unit 4 is the same language as yesterday's about units 1 & 2, but the part about teams of experts leads me to believe that Unit 4 is not going to be as easy a proposition. OTOH, with the other 3 under control, they will be able to concentrate on this Unit more fully.
 
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dorispulaski

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This recently on the IAEA site, and it very bad news:

Japan Earthquake Update (15 March 2011, 06:15 CET)
.by International Atomic Energy Agency (IAEA) on Monday, March 14, 2011 at 11:01pm.Japanese authorities informed the IAEA that there has been an explosion at the Unit 2 reactor at the Fukushima Daiichi plant. The explosion occurred at around 06:20 on 15 March local Japan time.



Japanese authorities also today informed the IAEA at 04:50 CET that the spent fuel storage pond at the Unit 4 reactor of the Fukushima Daiichi nuclear power plant is on fire and radioactivity is being released directly into the atmosphere.



Dose rates of up to 400 millisievert per hour have been reported at the site. The Japanese authorities are saying that there is a possibility that the fire was caused by a hydrogen explosion.



The IAEA is seeking further information on these developments. The IAEA continues to liaise with the Japanese authorities and is monitoring the situation as it evolves.



.
 

dorispulaski

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And from NEI.org, earlier:

UPDATE AS OF 10:25 P.M. EDT, MONDAY, MARCH 14:
Yukio Edano, Japan’s Chief Cabinet Secretary, during a live press conference at 10 p.m. EDT, said there is a fire at Fukushima Daiichi 4 that is accompanied by high levels of radiation between Units 3 and 4 at the site. The fire began burning at Unit 4 at around 6 a.m. Japan time on March 14 and is still burning. Fire fighters are responding to the fire. The reactor does not have fuel in the reactor, but there is spent fuel in the reactor (pool) and Edano said that he assumes radioactive substances are being released. “The substances are coming out from the No. 4 reactor and we are making the utmost effort to put out the first and also cool down the No. 4 reactor (pool).”

Edano said that a blast was heard this morning at Unit 2 at about 6:30 a.m. A hole was observed in the number 2 reactor and he said there is very little possibility that an explosion will occur at Unit 2.

“The part of the suppression chamber seems to have caused the blast,” Edano said. A small amount of radioactive substance seems to have been released to the outside.

TEPCO workers continue to pump sea water at 1, 2 and 3 reactors. “The biggest problem is how to maintain the cooling and how to contain the fire at No. 4.” At 10:22 a.m. Japan time, the radiation level between units 2 and 3 were as high as 40 rem per hour. “We are talking about levels that can impact human health.” Edano said.

Of the 800 staff that remained at the power plant, all but 50 who are directly involved in pumping water into the reactors have been evacuated.
 

dorispulaski

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Thank goodness, the IAEA confirms the fire is out.


Japanese Earthquake Update (15 March 07:35 UTC)
Japanese authorities have confirmed that the fire at the spent fuel storage pond at the Unit 4 reactor of Fukushima Daiichi nuclear power plant was extinguished on 15 March at 02:00 UTC.

Please note that all future communications from the IAEA regarding events in Japan will use the Coordinated Universal Time (UTC) standard.

The daily briefing from the IAEA is not yet posted, but should be up soon. Additionally, from the IAEA facebook page, IAEA will hold a technical briefing at 16:00 CET.

Further evacuations are continuing, but the radiation levels have dropped from the peak level. Values are given here.

Fukushima Daiichi Nuclear Power Plant Update



Radiation Dose Rates Observed at the Site



The Japanese authorities have informed the IAEA that the following radiation dose rates have been observed on site at the main gate of the Fukushima Daiichi Nuclear Power Plant.



At 00:00 UTC on 15 March a dose rate of 11.9 millisieverts (mSv) per hour was observed. Six hours later, at 06:00 UTC on 15 March a dose rate of 0.6 millisieverts (mSv) per hour was observed.

These observations indicate that the level of radioactivity has been decreasing at the site.

As reported earlier, a 400 millisieverts (mSv) per hour radiation dose observed at Fukushima Daiichi occurred between units 3 and 4. This is a high dose-level value, but it is a local value at a single location and at a certain point in time. The IAEA continues to confirm the evolution and value of this dose rate. It should be noted that because of this detected value, non-indispensible staff was evacuated from the plant, in line with the Emergency Response Plan, and that the population around the plant is already evacuated.

About 150 persons from populations around the Daiichi site have received monitoring for radiation levels. The results of measurements on some of these people have been reported and measures to decontaminate 23 of them have been taken. The IAEA will continue to monitor these developments.



Evacuation of the population from the 20 kilometre zone is continuing. The Japanese have asked that residents out to a 30 km radius to take shelter indoors. Japanese authorities have distributed iodine tablets to the evacuation centres but no decision has yet been taken on their administration.
 

dorispulaski

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Tokyo Electric has Issued several press releases:

Daini status March 15th, 13:00 Japanese time:
http://www.tepco.co.jp/en/press/corp-com/release/11031507-e.html

All 4 Reactors are now in cold shutdown, with offsite power on, and no refrigerant leaked into the containment vessel.

TEPCO still has not elaborated at the situation at Daiichi:

However, their view of what happened yesterday is:

Press Release (Mar 15,2011)
Damage to the Unit 4 Nuclear Reactor Building at Fukushima Dai-ichi Nuclear Power Station


At approximately 6:00am, a loud explosion was heard from within the
power station. Afterwards, it was confirmed that the 4th floor rooftop
area of the Unit 4 Nuclear Reactor Building had sustained damage.

After usage, fuel is stored in a pool designated for spent fuel.

Plant conditions as well as potential outside radiation effects are
currently under investigation.

TEPCO, along with other involved organizations, is doing its best to
contain the situation. Simultaneously, the surrounding environment is
being kept under constant surveillance.

The issue then is to keep pumping seawater into the 3 reactors while also maintaining the spent fuel rod pool in unit 4. Because there is significant radiation in the area, there will be significant difficulty rotating personnel to ensure none of the people involved with the pumping gets too high a yearly dose.
 
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dorispulaski

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The NEI update

UPDATE AS OF 9:15 A.M. EDT, TUESDAY, MARCH 15:
Fukushima Daiichi
Units 1 and 3 at Fukushima Daiichi are stable and cooling is being maintained through seawater injection. Primary containment integrity has been maintained on both reactors.

The Japan Atomic Energy Agency (JAEA) reported an explosion in the suppression pool at Fukushima Daiichi Unit 2, at 7:14 p.m. EDT on March 14. Reactor water level was reported to be at 2.7 meters below the top of the fuel. The pressure in the suppression pool decreased from 3 atmospheres to 1 atmosphere. Radiation readings at the site increased to 96 millirem per hour.

Dose rates at Fukushima Daiichi as reported at 10:22 p.m. EDT on March 14 were:


Near Unit 3 reactor building 40 rem/hr
Near Unit 4 reactor building 10 rem/hr
At site boundary 821 millirem/hr.
Kitaibaraki (200 km south of site) 0.4 millirem/hr.

We are working on getting updated information on radiation and dose rates at and near the plant.

Station personnel not directly supporting reactor recovery efforts have been evacuated, leaving approximately 50 staff members at the site. Operators are no longer in the main control room due to high radiation levels.

Safety relief valves were able to be re-opened and seawater injection into the reactor core was restarted around 1 a.m. EDT on March 15 and is continuing.

At Unit 4 on March 14 at approximately 8:38 p.m. EDT, a fire was reported in the reactor building. It is believed to have been from a lube oil leak in a system that drives recirculation water pumps. Fire fighting efforts extinguished the fire. The roof of the reactor building was damaged.

Fukushima Daini
All four reactors at Fukushima Daini are being maintained with normal cooling using residual heat removal systems.
 

dorispulaski

Wicked Yankee Girl
Joined
Jul 26, 2003
Country
United-States
The IAEA just posted its afternoon update. We will have to wait several hours till they unveil the UN plan for how exactly they intend to help in Japan. TEPCO has not updated its Daiichi status today.

Musing on lessons going forward, for the US, I think a plan where equipment and trained people are made immediately available to people in an emergency should be in place. I know that sounds vague, but right off Japan's coast is the USS Ronald Reagan, a huge ship with many trained nuclear technicians and damage control people aboard. We also have huge helicopters that could have lifted entire diesel generators, huge batteries, things like that. I am perhaps being naive, but I wish we could have helped somehow, before things got to this position.

All the other nuclear sites in Japan, other than Daiichi, are in a safe state.

At Daiichi, Units 1 & 3 are being cooled by seawater, as long as there are people to man the pumps. Their containment vessels are intact. Efforts are still underway to get external power to Daiichi, which would certainly help with pumping, if nothing else. There is external power 10 km away at Daina. I hope the line crews get power to Daiichi soon.

Seawater is also being pumped into Unit 2's reactor, whose containment vessel has some size of hole in it, "small" is a relative term, and not as relative as is how much radioactive material is leaking through the hole-. The radiation measurements in the area are in the update below. In one sense, what you have for sure is a permanently open air vent in a reactor whose problems, in addition to loss of cooling function, were that its designed air vent was stuck closed.

Those worrying about Unit 4 should recall that the reactor there has not been fueled, and therefore cannot meltdown itself. Concern there is about the spent fuel rod containment pool, still a worry, but not as big a worry as if the reactor were fueled.

Japanese Earthquake Update (15 March 14:10 UTC)
.by International Atomic Energy Agency (IAEA) on Tuesday, March 15, 2011 at 7:30am.
The IAEA Incident and Emergency Centre (IEC) continues to monitor the status of the nuclear power plants in Japan that were affected by the devastating earthquake and consequent tsunami.



All units at the Fukushima Daini, Onagawa, and Tokai nuclear power plants are in a safe and stable condition (i.e. cold shutdown).

The IAEA remains concerned over the status of the Fukushima Daiichi nuclear power plant, where sea water injections to cool the reactors in units 1, 2 and 3 are continuing. Attempts to return power to the entire Daiichi site are also continuing.

After explosions at both units 1 and 3, the primary containment vessels of both units are reported to be intact. However, the explosion that occurred at 04:25 UTC on 14 March at the Fukushima Daiichi unit 2 may have affected the integrity of its primary containment vessel. All three explosions were due to an accumulation of hydrogen gas.



A fire at unit 4 occurred on 14 March 23:54 UTC and lasted two hours. The IAEA is seeking clarification on the nature and consequences of the fire.



The IAEA continues to seek details about the status of all workers, reactors and spent fuel at the Fukushima Daiichi plant.



An evacuation of the population from the 20-kilometre zone around Fukushima Daiichi is in effect. The Japanese have advised that people within a 30-km radius shall take shelter indoors. Iodine tablets have been distributed to evacuation centres but no decision has yet been taken on their administration.



A 30-kilometre no-fly zone has been established around the Daiichi plant. Normal civil aviation beyond this zone remains uninterrupted. The Japan Coast Guard established evacuation warnings within 10 kilometres of Fukushima Daiichi and 3 kilometres of Fukushima Daini.



The IAEA and several other UN organizations held a meeting at 11:00 UTC today to discuss recent developments and coordinate activities related to consequences of the earthquake and tsunami. The meeting was called under the framework of the Joint Radiation Emergency Management Plan of the International Organizations, and this group expects to work closely together in the days ahead.


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mot

On the Ice
Joined
Feb 17, 2010
In one sense, what you have for sure is a permanently open air vent in a reactor whose problems, in addition to loss of cooling function, were that its designed air vent was stuck closed.

Ah! I wish Japanese media had told me that!
 

Violet Bliss

Record Breaker
Joined
Nov 19, 2010
The problem with most of the energy technologies is the extreme competence in generation and extraction with extreme inadequacy in containment and control of damages and consequences. Such inbalance in knowledge plus the rackless haste to proceed almost guarantee catastrophic events such as nuclear meltdowns and deep sea oil spill and spew.

When not enough attention is paid to the "what ifs", we all have to deal with "what now".
 
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