Japanese Earthquake, Tsunami, and Nuclear Reactors

[dorispulaski]

This doesn't make a lot of sense to me; I'm sure either money or politics is involved, but I have no clue how. It's a logarithmic scale. I could see Level 6, since Fukushima is worse than TMI, which was basically nothing but 1979's version of an Orson Wells "War of the Worlds" radio scare. However, Fukushima is still at least 10x less than Chernobyl. Since level 7 is Chernobyl, according to the scale, this makes no sense at all, especially since NISA admits that Fukushima is significantly less than Chernobyl.

The scale needs new levels and a lot of work.

For one thing, at Chernobyl, a significant number of people died due to exposure to radiation in the first month. We've had no one die in the first month.

Japan to raise Fukushima crisis level to worst

The Japanese government's nuclear safety agency has decided to raise the crisis level of the Fukushima Daiichi power plant accident from 5 to 7, the worst on the international scale.

The Nuclear and Industrial Safety Agency made the decision on Monday. It says the damaged facilities have been releasing a massive amount of radioactive substances, which are posing a threat to human health and the environment over a wide area.

The agency used the International Nuclear and Radiological Event Scale, or INES, to gauge the level. The scale was designed by an international group of experts to indicate the significance of nuclear events with ratings of 0 to 7.

On March 18th, one week after the massive quake, the agency declared the Fukushima trouble a level 5 incident, the same as the accident at Three Mile Island in the United States in 1979.

Level 7 has formerly only been applied to the Chernobyl accident in the former Soviet Union in 1986 when hundreds of thousands of terabecquerels of radioactive iodine-131 were released into the air. One terabecquerel is one trillion becquerels.

The agency believes the cumulative amount from the Fukushima plant is less than that from Chernobyl.

Officials from the agency and the Nuclear Safety Commission will hold a news conference on Tuesday morning to explain the change of evaluation.

Tuesday, April 12, 2011 05:47 +0900 (JST)

 

[mot]

This doesn't make a lot of sense to me; I'm sure either money or politics is involved, but I have no clue how. It's a logarithmic scale. I could see Level 6, since Fukushima is worse than TMI, which was basically nothing but 1979's version of an Orson Wells "War of the Worlds" radio scare. However, Fukushima is still at least 10x less than Chernobyl. Since level 7 is Chernobyl, according to the scale, this makes no sense at all, especially since NISA admits that Fukushima is significantly less than Chernobyl.

The scale needs new levels and a lot of work.

For one thing, at Chernobyl, a significant number of people died due to exposure to radiation in the first month. We've had no one die in the first month.

Yeah, wonder what happened to level 6?
As long as levels are set as comparison to the past incidents, they are to me nothing but rhetorical. They might as well say 'it's worse than the Three Miles, but not as but as Chernobyl yet' instead? They need their own version of COP.

 

[dorispulaski]

Yes, I think they do. That's one thing that needs to be addressed in upcoming conferences. Another thing that needs to be addressed is to get a real consensus on modelling health effects of radiation and radioactive materials, so we don't have the UN saying 1000 Becquerels per kg is OK in food and some country saying only 300 becquerels per kg is OK. This stuff should not be a matter of opinion, but a matter of math and science.

What? They don't have it right yet? Well, not in my opinion.

There are two competing main models, and in my opinion, mathematically, both are on their face bull.

One of them says that health risk is a linear function of exposure with no threshold. However, there are areas on earth that are naturally hundreds of times higher in background radiation than others, and no one has ever been able to prove that people that live in more radioactive places, like Finland, or Denver, Colorado, or the western part of Washington State, have more cancers or other radiation related health problems than people who live at sea level in a place where there is no granite bedrock (which outgases radon). Worse, conceptually, this is like saying, if we know that people who stick their hands in boiling water will burn their hands, therefore if a million people stick their hands in room temperature water, there is some chance that some of them will burn their hands. It leads to requirements in the US that sites with nuclear waste of some sort (say Hanford) must be cleaned up to have a lower level of radiation than the background radiation.

The competing hyposthesis is no better. They say that there is a threshold for damage, otherwise it's linear. Which is like saying if people are exposed to 500 units of radiation, all is good, but at 500.001 some percentage of people will start having effects. They get around the absurdity by saying no one knows just what the threshold is, but it's still a bad model on the face of it.

However, because these are public health issues, the models were created in the 50's and 60's and embedded in law, and the bugger factors in the calculation are the places where the battlegrounds are fought. No one has the real will or juice to change these things.

Meanwhile, animal studies show that low dose radiation may in some cases at least, be good for you, which doesn't fit in either model. Exposed animals got fewer cancers than unexposed animals.

I wish I were better at math. I hope somebody who is will do a decent model of the situation.

I think that how this should go is that the probability of getting cancer is a function of the likelihood of a DNA strands being broken (which goes up with radiation), and not either being healed (which is better at low dose, but overwhelmed at high dose) or a cell dying (which is another natural protective mechanism you have, that also gets overwhelmed), and then bugger factors for what exactly you are exposed to (there are a wide variety of things).

With computers, all these models can be calculated, but that stuff wasn't done that way back in the day.

 

[dorispulaski]

More problems with electrical panels, this time with water monitoring equipment. Fortunately, this is not inside any of the reactors or turbine buildings. There is something to be said for having 12 to 13 fire trucks on site at all times. It would be a good idea in any nuclear disaster, I think, even if you are not pumping water on spent fuel pools.

Press Release (Apr 12,2011)
Fire at the sampling equipment at the water discharge channel, Unit 1-4, Fukushima Daiichi Nuclear Power Station


At approximately 6:38 AM, April 12th, fire has been found at the distribution switchboard containing batteries located in the sampling equipment switchbox situated close to the south water discharge channel for Unit 1-4. The self defense fire fighting team conducted the fire fighting at an early stage. At the same time, at approximately 6:45 AM, we reported to the Futaba fire authorities. As a result of the fire fighting, it is confirmed that the fire has been under control without fire or smoke.

There is no impact on the external release of radioactive substances or on the cooling capability of the reactor from this incident. There has been no change on the monitoring figures of the surrounding environment. We will continue monitoring the status of the plant and the surrounding environment around the Power Station. We will investigate the cause in detail.

 

[dorispulaski]

And Secretary Clinton is going to Japan. This from NHK:

It will be an odd meeting: Clinton is a lawyer by trade, not an engineer. It is interesting to speculate what presidential level conversations she will be having about the US helping with Daiichi. Of course, she could be offering to store some of the radioactive junk at WIPP or Idaho National Lab. If she's looking for a laundary list to take back, some TEPCO folk should be there to ask for what they might want. Of if she's offering a laundary list, there should be some NRC, US Navy, or NEI people there to say what we could offer.

Very odd indeed.

It should be remembered that Obama is fairly committed to nuclear energy and reaffirmed that support early into this disaster. He mentioned it in his State of the Union, too. And in fact, his largest ticket early financial supporters in the Democratic primary were people that work at Exelon. Exelon is centered in Illinois, and has the US's largest fleet of reactors.

I'm sure Obama wants this to turn out fairly well.

Perhaps the US military has expertise in cleaning up nuclear waste on battlefields, at least theoretically? It's the sort of thing we thought about during the Cold War. Perhaps there will be sekret stuff changing hands.

Perhaps the US will join with Japan to work on the seabed initiative for storing nuclear waste, using the Daiichi trash as test cases. (The seabed initiative has located a section of the seabed a long way off Hawaii that is 4 miles deep and has pretty much no life, and deep, deep layers of soft sediment. Stuff dropped into it disappears, so you use pointy ended capsules.

Clinton to visit Japan on Sunday

US Secretary of State Hillary Clinton will visit Japan on Sunday to underline US support for the country as it struggles to recover from last month's devastating quake and tsunami.

The US State Department says Clinton will travel to Tokyo after attending a NATO foreign ministers conference in Germany from Wednesday through Friday, and holding talks in South Korea with President Lee Myung Bak on Saturday.

While in Japan, she will meet with Prime Minister Naoto Kan and Foreign Minister Takeaki Matsumoto.

They are expected to discuss how the United States can help Japan rebuild and deal with the crippled Fukushima Daiichi nuclear plant.

Clinton also plans to meet survivors of the disaster and to visit the Imperial Palace to extend her sympathy to the Emperor and Empress.

Tuesday, April 12, 2011 09:49 +0900 (JST)

.

When I saw the headline, I thought Bill & his Clinton Global Initiative were involved.

 

[Olympia]

Interesting about Bill Clinton. Remember that he and Bush 41, George H.W. Bush, have experience coordinating American assistance for tsunamis, as personal emissaries of George W. Bush. So maybe he'll have some advice or connections that can help with some aspect of the disaster in Japan.

 

[dorispulaski]

Olympia, I was indeed thinking of Bill's tsunami experience in Indonesia, and his earthquake experience in Haiti, as well. I've been surprised that he has not been involved, and wondered why. Perhaps he would need a direct invitation from President Obama? I'm not sure how this works, particularly since his wife is part of this administration.


NHK has reported on NISA's criteria for lifting the classification of the event to Level 7, but frankly it looks like Level 6 is the better call, since they report 1/10 of the radioactive material released into the air as Chernobyl. As reported at NHK, the purpose of this event seems to me to be saying, "See, this is not as bad a Chernobyl." They are basing it on the amount of material in air and water, compared to somebody's guess of what was relesed at Chernobyl. This would explain TEPCO's being so very exact about how much water they had pumped overboard.

And then grading it as equal to Chernobyl. Perhaps it is in response to the criticism that NISA has received, and for which it apologized yesterday? In any case, classification on this scale is apparently required for NISA, as signatories to some agreement, either UN or otherwise, by the sound of it.

Nuclear accident level raised to maximum

Japan's nuclear safety agency has raised the crisis level at the stricken Fukushima Daiichi nuclear power plant to 7, from the current 5.

The agency told reporters on Tuesday that large volumes of radioactive substances that could affect human health and the environment are being released in a wide area.

Level 7 is the highest rank on an international standard and equivalent to the severity recorded after the Chernobyl disaster in 1986.

But the agency said the volume of radiation from Fukushima is one-tenth that at Chernobyl.

The agency said its calculations show that 370-thousand terabecquerels of radioactive iodine 131 and cesium 137 have been released from the plant.

The nuclear safety commission, in a joint press conference with the agency, put the estimated leak at 630-thousand terabecquerels of both substances.

One terabecquerel is equivalent to one trillion becquerels. Both organizations say the leak constitutes a level-7 crisis.

Senior agency official Hidehiko Nishiyama said 29 people died of acute radiation exposure at Chernobyl but there are no fatal radiation casualties at Fukushima.

He added that at Chernobyl the nuclear reactor itself exploded in contrast to the Fukushima plant, which was damaged by hydrogen explosions. He said the reactors themselves retain their shape.

Nishiyama also said the upgrade does not affect the existing evacuation plan, which was made on the basis of the same radiation evaluation.

The agency is required to announce the severity of a crisis at a nuclear facility based on the international standard from zero up to 7 set by the International Nuclear Event Scale.

Tuesday, April 12, 2011 13:09 +0900 (JST)

Additionally, NHK is crediting the most of the radiation as coming from the explosion(s) at the spent fuel pool (s). I do wonder why they are assiduously not mentioning the Unit 4 spent fuel pool. Ignoring it was perhaps TEPCO's biggest mistake, in handling this crisis. Perhaps this works this way: Unit 2's spent fuel pool explosion caused the water leakage from Unit 2, as well as the release of radiation to the air?

Much of radiation leaked on Mar.15,16

Japan's Nuclear Safety Commission says that abnormalities in a reactor suppression pool were to blame for the release of large amounts of radioactive substances at the Fukushima nuclear power plant.

It said much of the radiation was released during the 2 days after the suppression pool, connected to the No. 2 reactor, began showing problems at 6 AM on March 15.

The commission said that radiation is still escaping and the [ETA total] amount is rising marginally, but that the volume [ETA per day] has dropped considerably since the crisis began.

Tuesday, April 12, 2011 14:39 +0900 (JST)

TEPCO responds with an apology

.TEPCO issues apology

Tokyo Electric Power Company, or TEPCO, says it is taking the Nuclear Safety Agency's decision seriously and is deeply sorry for causing trouble and concern.

TEPCO official Junichi Matsumoto acknowledged that a level-7 disaster means a massive release of radiation.

Matsumoto said he offers his sincerest apologies to people living near the nuclear plant, the residents of Fukushima Prefecture, and all members of the public. He said TEPCO will do all it can to bring the situation under control.

Matsumoto stopped short of releasing details on the exact volume of radiation from the plant, because the utility is still assessing all relevant data.

Tuesday, April 12, 2011 12:56 +0900 (JST)

Meanwhile, today TEPCO is going to start pumping more highly contaminated water into various tanks, starting with getting more of the really nasty stuff out of Unit 2's basement and turbine building and trenches and into the turbine building condenser that they just emptied into the Contaminated Waste Storage Tank.

TEPCO knows its business better than I do, but the pressure not rising much at Unit 1 over the last couple days is not bad news. Also the temperature started dropping a little bit at Unit 1. As long as the positive nitrogen pressure is kept on so oxygen isn't getting in, this avoids them having to vent.

TEPCO to resume removing contaminated water

The operator of the crippled Fukushima Daiichi nuclear plant expects to resume the removal of highly radioactive water as early as Tuesday, after a one-day delay due to a strong aftershock.

Tokyo Electric Power Company will begin pumping contaminated water from the Number 2 reactor and transferring it to a condenser, after checking the safety of equipment.

The radioactive water has been hampering work to restore cooling functions in the damaged reactors.

TEPCO says it also resumed injecting nitrogen into the containment vessel of the No.1 reactor late on Monday night.

The work is aimed at preventing further hydrogen explosions. It was suspended because of the strong quake earlier in the day.

TEPCO now suspects a possible leakage of gas from the containment vessel, as its internal pressure has barely risen over the past few days despite the injection of nitrogen.

Radiation levels around in the area have not changed, however, and the utility plans to continue the injection while monitoring the situation closely.

Tuesday, April 12, 2011 13:12 +0900 (JST)

.

The Japanese government is doing more measurements in Fukushima, so that all residents know exactly what their exposure is, town by town. They also need to do this if they want to selectively evacuate people due to dose issues.

.Fukushima radiation measurement program

The Fukushima prefectural government has begun a program to measure radiation levels at more than 2700 locations across the region.

In response to residents' concerns, on Tuesday officials began examining radiation levels at 2,757 sites in 55 municipalities around the prefecture.

However, they plan to exclude the area within a 20-kilometer radius of the Fukushima Daiichi nuclear power plant, where residents have been instructed to evacuate.

In front of the Iwaki railway station, officials measured radiation levels at 1 centimeter and 1 meter above the ground.

A local resident said he is concerned about the level of radiation where he lives and wants the authorities to provide the public with accurate information.

The prefectural survey will continue through Friday and include levels of iodine and cesium in the soil.

Tuesday, April 12, 2011 15:11 +0900 (JST)

And in my view, these are the people who perhaps should apologize. There was a half hour between the quake and the tsunami. A lot of people could have left for higher ground.

Tsunami warning system to be improved

Japan's Meteorological Agency says it will improve its tsunami warning system so that it can give quicker and more accurate alerts after strong earthquakes.

When an earthquake hits, the agency collects data from seismometers across the country to estimate the magnitude. If necessary, it announces preliminary tsunami warnings and advisories within minutes.

But the agency initially underestimated the magnitude for the March 11th quake, rating it a 7.9 instead of a 9.0. It also predicted that a tsunami of up to 6 meters would hit northeastern Japan.

It took over 40 minutes for the agency to revise the estimated height to above 10 meters after studying more detailed data.

The Meteorological Agency says it takes 30 minutes to accurately calculate the strength of a huge quake as it uses seismic data from overseas as well as Japan to determine a precise figure.

Senior agency official Osamu Kamigaichi says the agency did the best it could with its technology, but failed to save many people's lives.

He stresses the agency will do its best to develop technology to quickly determine a quake's magnitude, the height of any tsunami, and issue accurate alerts.

Tuesday, April 12, 2011 05:47 +0900 (JST)

.

 

[dorispulaski]

IAEA provides more info on the upgrade to Level 7. Apparently now reactors 1, 2, and 3 are grouped together as a single incident (they were listed separately before, which made no sense to me.) However, unit 4 is still listed as level 3 (having only local effect) which still doesn't quite make sense to me, particularly as the Unit 4 spent fuel pool blew up at 6 am on March 15th, and was definitely part of the massive release of radioactive material on that date.:

IAEA Update on Fukushima Nuclear Accident (12 April 2011, 4:45 UTC)
The Japanese Nuclear and Industrial Safety Agency (NISA) today issued a new provisional rating for the accident at the Fukushima Daiichi nuclear power plant on the IAEA International Nuclear and Radiological Event Scale (INES).

The nuclear accident at Fukushima Daiichi is now rated as a level 7 "Major Accident" on INES. Level 7 is the most serious level on INES and is used to describe an event comprised of "A major release of radioactive material with widespread health and environmental effects requiring implementation of planned and extended countermeasures". Japanese authorities notified the IAEA in advance of the public announcement and the formal submission of the new provisional rating.

The new provisional rating considers the accidents that occurred at Units 1, 2 and 3 as a single event on INES. Previously, separate INES Level 5 ratings had been applied for Units 1, 2 and 3. The provisional INES Level 3 rating assigned for Unit 4 still applies.

The re-evaluation of the Fukushima Daiichi provisional INES rating resulted from an estimate of the total amount of radioactivity released to the environment from the nuclear plant. NISA estimates that the amount of radioactive material released to the atmosphere is approximately 10 percent of the 1986 Chernobyl accident, which is the only other nuclear accident to have been rated a Level 7 event.

Earlier ratings of the nuclear accident at Fukushima Daiichi were assessed as follows:

On 18 March, Japanese authorities rated the core damage at the Fukushima Daiichi 1, 2 and 3 reactor Units caused by loss of all cooling function to have been at Level 5 on the INES scale. They further assessed that the loss of cooling and water supplying functions in the spent fuel pool of the Unit 4 reactor to have been rated at Level 3.

Japanese authorities may revise the INES rating at the Fukushima Daiichi nuclear power plant as further information becomes available.

INES is used to promptly and consistently communicate to the public the safety significance of events associated with sources of radiation. The scale runs from 0 (deviation) to 7 (major accident).

For further information on the INES scale: http://www-ns.iaea.org/tech-areas/emergency/ines.asp

Further details regarding this development can be found in the following NISA press release [pdf]

Only Cesium and Iodine in the air are considered as part of what NISA is adding up to get their total released dose in the pdf file. And iodine and cesium are the only things that I am aware that people have found elsewhere. If someone outside Japan had found plutonium, they would surely have told us, for sure. Chernobyl released massive amounts of plutonium and strontium, as well as cesium and iodine, which were detected in places other than Ukraine, Russia & Belarus.

 

[dorispulaski]

Finally, back to the current data:

wind in the northwest
All data as of 9 am, April 12th
Gamma Radiation
Daini Measure Point 42.7 microSieverts per hour
Daiichi West Gate 41.6 microSieverts per hour

Radiation Dose
Daiichi Main Buillding, 0.58 milliSieverts per hour
Daiichi Main Gate, 78 microSieverts per hour
Daiichi, West Gate, 33 microSieverts per hour
Daiichi, Eight peripheral measuring points (11,38,36,35,65,106,223,191) microSieverts per hour

JAIF's air chart, updated to April 11th. Every point is still decreasing. Iitate Village has dropped to about 4 microSieverts per hour, and is consistently the highest point on the chart. From the interview of the mayor yesterday, we learned that only some spots in Iitate Village are highly contaminated. I'd like to see more info on this.

http://www.jaif.or.jp/english/news_images/pdf/ENGNEWS01_1302577390P.pdf

JAIF's chart of concentrations of radioactive material is sea water http://www.jaif.or.jp/english/news_images/pdf/ENGNEWS01_1302577437P.pdf

JAIF reports that three measuring points have been added off Muroran, Erimo and Kuroshan, to the north of Daiichi by 500 to 600 km. There are no data from those points as yet. They also show a bar chart (as they have right along) of Tepcos and MEXT's sampling points. They have added a bar for the sand lance fish, which shows that at some point recently, sand lances had just less than the regulation amount of cesium in them.


TEPCO issued an April 12th 9 AM status

* Below is the status of TEPCO's major facilities due to the 7.1 magnitude earthquake centered in the Fukushima-Hama-dori earthquake which occurred at approximately 5:16 pm, April 11th 2011. - No abnormalities were detected in the parameter of each of the units.
- Nitrogen gas injection to the reactor containment vessel of unit1 was suspended and was resumed at 11:34 pm.
- The water level of units1-3's pit did not change significantly.
- We confirmed that there were no injured workers inside of the building.

. Spraying inhibitor

From 3:00 pm, April 1st, we started spraying an inhibitor in order to prevent the diffusion of radioactive materials. This attempt was conducted on a trial basis at the mountain side area of the common spent fuel pool at the range of 500m2. The spraying finished at 4:05 pm. On April 5th, we also sprayed the east and south side and the mountain side area of the common spent fuel pool of unit 4 at a total range of 600 m2. On April 6th, spraying was conducted at the mountain side area of the common spent fuel pool at a range of 600m2, on April 8th, 680m2, and on April 10th, 550m2. On April 11th, we conducted spraying at a range of 1,200m2

 

[let`s talk]

www.youtube.com/watch?v=GhsxjGnQPKg
A Japanese journalist Tetsuo Jimbo inside Fukushima 30km evacuation zone, with a dosimeter glued to the dashboard on April 3rd. In Japanese, with English subtitles.

Report in English about the trip:
www.youtube.com/watch?v=JcmSnWM_5Fs

 

[dorispulaski]

NEI's 11:30 am Eastern Daylight Time summary
The NHK report claimed the major release was due to a unit 2 spent fuel pool. NEI says it is the hydrogen explosion in the suppression pool, which makes a lot more sense to me.

UPDATE AS OF 11:30 A.M. EDT, TUESDAY, APRIL 12:
Tokyo Electric Power Co. (TEPCO) is planning to pump highly radioactive water from reactor 2 into a condenser, as the utility works to control radiation and restore cooling systems at the Fukushima Daiichi nuclear power plant.

TEPCO continues to inject cooling water into reactors 1, 2 and 3 and to spray water into the used fuel pools for reactors 1-4. TEPCO also continues injection of nitrogen gas into the containment vessel of reactor 1 to prevent a possible explosion of hydrogen that may be accumulating inside.

A fire that broke out early Tuesday at a distribution switchboard near the south water discharge channel for reactors 1-4 was extinguished without interruption of reactor cooling operations or the release of radioactivity, TEPCO said.

The crisis rating of the Fukushima Daiichi accident was raised from 5 to 7 on the seven-level International Nuclear and Radiological Event Scale by the Japan Nuclear and Industrial Safety Agency. The new level, the highest on the scale, designates Fukushima as a “major accident.” The new rating puts the Japanese incident on the same level as the 1986 Chernobyl accident—even though Japanese authorities estimate that radiation released at Fukushima is only 10 percent of the amount released from the Ukrainian plant.

Authorities said much of the high-level radiation leaked from reactor 2 on March 15 and 16, early in the accident. Abnormalities in the reactor’s suppression pool caused the radiation release, the Japan Nuclear Safety Commission said. Radiation continues to leak from the suppression pool, the commission said, but the volume has dropped considerably.
UPDATE AS OF 8:30 A.M. EDT, TUESDAY, APRIL 12:
Japan’s nuclear safety agency has raised the crisis level of the Fukushima Daiichi accident from 5 to 7 on the seven-level International Nuclear and Radiological Event Scale. The new rating puts the Japanese incident on the same level as the 1986 Chernobyl accident—even though Japanese authorities estimate that radiation released at Fukushima is only 10 percent of the amount released from the Ukrainian plant.

The new level designates Fukushima as a “major accident,” up from an “accident with wider consequences.” Level 7, the highest on the scale, describes an event with “a major release of radioactive material with widespread health and environmental effects requiring implementation of planned and extended countermeasures," according to the International Atomic Energy Agency, which sponsors the ratings.

For the new rating, the Japan Nuclear and Industrial Safety Agency combined the accidents at reactors 1, 2 and 3 as a single event. Previously, separate level 5 ratings had been applied to each reactor. The earlier level 3 rating (“serious incident”) still applies to reactor 4.

Japanese authorities may revise the INES rating at the power plant as more information becomes available.

I suspect that's what is behind the one month delay in evacuating Iitate Village, Namie, and several other small towns for 30 days. NISA wants to see what happens to the dose rate.


More from NHK

●Japan puts priority on public health
Japan's top government spokesman says he feels very sorry for troubling the Japanese people and international community due to the unfortunate accident at the Fukushima Daiichi nuclear power plant. Chief Cabinet Secretary Yukio Edano made the remark at a news conference on Tuesday, in reference to the nuclear safety agency's raising of the crisis level of the accident from 5 to 7 -- the most dangerous ranking. Edano said the agency's move indicates the seriousness of the accident. However, he said that unlike the Chernobyl disaster in 1986, the Fukushima case has caused no direct health problems and that Japan's government will put top priority on protecting public health. Edano said the scale of the accident at Fukushima is evaluated at the same rank as the Chernobyl disaster but that the 2 cases are quite different in many ways.
Tuesday, April 12, 2011 15:11 +0900 (JST)

TEPCO reports

Daini 3:00 PM on April 12th
Daini now reports for all the measuring points on its periphery, except measure point 7, which was completely destroyed by the tsunami:
(3.1, 2.3, 3.4, 2.7, 2.6, 2.6) microSieverts per hour for measure points 1,2,3,4,5,6,8. Wind velocity there is 12.9 meters per second north-northwest.

Daiichi 3:00 PM on April 12th
(11, 38, 36, 35, 65, 106, 224, 190) microSieverts per hour for measure points 1-8. Wind velocity is

Main Building 0.56 milliSieverts per hour
Main Gate 78 microSieverts per hour
West Gate 33 microSieverts per hour (gamma radiation is 41.2 microSieverts per hour) Wind is 2.8 m/s west

TEPCO April 12th 7:00 PM

Operation for cooling the spent fuel pools -From 4:26 pm to 5:16 pm on April 12th, we conducted water spraying to Unit 3 by the concrete pumping vehicle.

-In regard to the earthquake occurred at 2:07 pm on April 12th with a magnitude of 6.3, epicenter in the Fukushima-Hama-dori, no trouble were detected in the plant units after the earthquake. Safety of workers has also been confirmed.
Today, in order to confirm the conditions of the fuels stored in the spent fuel pool of Unit 4, we sampled the water in the spent fuel pool. We will be conducting nuclide analysis on these samples.

TEPCO has issued another apology, signed by the company's president, because of the rerating of the disaster.

TEPCO also has trend charts of seawater analysis:

Seawater analysis. Dropping a lot at Daiichi itself since they stopped dumping.at Daiichi
http://www.tepco.co.jp/en/press/corp-com/release/11041209-e.html
Mixed grill and small changes in other areas as the spill spreads out.
http://www.tepco.co.jp/en/press/corp-com/release/11041210-e.html
http://www.tepco.co.jp/en/press/corp-com/release/11041210-e.html

 

[dorispulaski]

The IAEA has a number of updates:

IAEA Briefing on Fukushima Nuclear Accident (12 April 2011, 14:30 UTC)

On Tuesday, 12 April 2011, the IAEA provided the following information on the current status of nuclear safety in Japan:

1. Current Situation

Overall, the situation at the Fukushima Daiichi plant remains very serious, but there are early signs of recovery in some functions such as electrical power and instrumentation.

Provisional INES Level 7 Rating
The International Atomic Energy Agency (IAEA) can confirm that the Nuclear and Industrial Safety Agency (NISA) has submitted a provisional International Nuclear and Radiological Event Scale (INES) Level 7 rating for the accident at the Fukushima Daiichi nuclear power plant. This new provisional rating considers the accidents that occurred at Units 1, 2 and 3 as a single event on INES and uses estimated total release to the atmosphere as a justification. Previously, separate provisional INES Level 5 ratings had been applied for Units 1, 2 and 3.

Japanese authorities notified the IAEA in advance of the public announcement and the formal submission of the new provisional rating.

The provisional rating was determined by NISA after it received the results of the analysis conducted by the Japan Nuclear Energy Safety Organization (JNES). NISA then applied the INES assessment methodology to calculate the total estimated release in terms of radiological equivalence to I-131. Based on this provisional assessment, NISA concluded that the accident would be provisionally rated INES Level 7 as per the definition below, taken from the INES User's Manual, 2008 Edition [pdf]:

Level 7

"An event resulting in an environmental release corresponding to a quantity of radioactivity radiologically equivalent to a release to the atmosphere of more than several tens of thousands of terabequerels of I-131."

NISA estimates that the release of radioactive material to the atmosphere is approximately 10% of the Chernobyl accident, which is the only other accident to have an INES Level 7 rating.

Protective Measures
"On 11 April the Government of Japan announced that they had concluded to establish 'Planned Evacuation Areas' and 'Evacuation prepared Area' in the areas beyond the 20km radius from the Fukushima Daiichi nuclear power plant. The review was conducted because the Government consider the safety of residents its first priority.

The Government of Japan considered the standards recommended by the International Commission on Radiological Protection (ICRP) and the International Atomic Energy Agency (IAEA) as part of the review.

About the 'Planned Evacuation Areas', the Japanese authorities have found that the areas beyond 20 km radius could be exposed to over 20mSv during the course of the next one year, approximately until next March. Therefore the Government of Japan will be consulting with the local communities in terms of planned evacuations, ant at this juncture they are hoping that this planned evacuation will be carried out during the next month to come. The Planned Evacuation Areas that have been newly designated for evacuation include Kutsurao village, Namie town, Iitate village, a part of Kawamata town and a part of Minami Souma City.

The Government also defined a second new area called the 'Evacuation Prepared Area'. This area includes the area previously defined as the 'Indoor Evacuation Area' between 20 and 30 km from Fukushima Daiichi, but excludes those areas designated above as 'Planned Evacuation Areas'.

Within the 'Evacuation Prepared Area' people living in this area should be prepared for indoor evacuation or evacuation (outside of this area) in case of emergency. Voluntary evacuation is recommended within this area. Children, pregnant women, people who require nursing care and those who are hospitalized should not enter this area. Kindergartens, pre-schools, elementary schools, junior-high schools and high school will be closed within this area."

Earthquake of 11 April
The IAEA confirms that an earthquake occurred in Japan at 08:16 UTC, 11 April.

The IAEA International Seismic Safety Centre rated it as a 6.6 magnitude, revised from an initial 7.1 magnitude. The epicenter of the earthquake was in Fukushima Prefecture, 68 km from the Daiichi nuclear power plant. The epicenter was inland at a depth of 13.1 km.

The IAEA contacted NISA who confirmed the following regarding the status of the Fukushima Daiichi nuclear power plant:

No changes were observed on the readings at the on-site radiation monitoring posts;
Workers were temporarily evacuated to the seismic evacuation shelter;
Off-site power was lost and water injection pumps for Units 1, 2 and 3 stopped but were restarted 50 minutes after the earthquake; and the injection of nitrogen into Unit 1 stopped and resumed later.
Changes to Fukushima Daiichi Plant Status

In Unit 1 fresh water is being continuously injected into the RPV through the feed-water line at an indicated flow rate of 6 m3/h using a temporary electric pump with off-site power. In Units 2 and 3 fresh water is being continuously injected through the fire extinguisher lines at an indicated rate of 7 m3/h using temporary electric pumps with off-site power.

Nitrogen gas is being injected into the Unit 1 containment vessel to reduce the possibility of hydrogen combustion within the containment vessel. The pressure in this containment vessel is increasing due to the addition of nitrogen. The pressure in the RPV is increasing as indicated on both channels of instrumentation. In Units 2 and 3 Reactor Pressure Vessel and Drywell pressures remain at atmospheric pressure.

RPV temperatures remain above cold shutdown conditions in all Units, (typically less than 95 °C). In Unit 1 temperature at the feed water nozzle of the RPV is 221 °C and at the bottom of the RPV is 120 °C. In Unit 2 the temperature at the feed water nozzle of the RPV is 155 °C. The temperature at the bottom of the RPV was not reported. In Unit 3 the temperature at the feed water nozzle of the RPV is 97 °C and at the bottom of the RPV is 111 °C.

There has been no change in status in Units 4, 5 and 6 and the Common Spent Fuel Storage Facility.

2. Radiation Monitoring
On 11 April, deposition of both iodine-131 and cesium-137 was detected in 6 and 8 prefectures respectively. The values reported for iodine-131 ranged from 2.1 to 35 Bq/m2 and for cesium-137 from 5.2 to 41 Bq/m2.

Gamma dose rates are measured daily in all 47 prefectures, the values tend to decrease. For Fukushima, on 11 April a dose rate of 2.1 µSv/h, for the Ibaraki prefecture a gamma dose rate of 0.15 µSv/h was reported. The gamma dose rates in all other prefectures were below 0.1 µSv/h.

Dose rates are also reported specifically for the Eastern part of the Fukushima prefecture, for distances of more than 30 km to Fukushima-Daiichi. On 11 April, the values in this area ranged from 0.2 to 25 µSv/h.

In an additional MEXT monitoring programme, on 11 April measurements were reported for 25 cities in 13 prefectures. In Fukushima City, a value of 0.42 µSv/h was observed. In all other cities, gamma dose rates ranged from 0.04 to 0.13 µSv/h. Typical normal background levels are in the range of 0.05 to 0.10 µSv/h.

On 11 April, the IAEA Team made measurements at 9 different locations in the Fukushima area at distances of 30 to 58 km, West to Northwest from the Fukushima nuclear power plant. At these locations, the dose rates ranged from 0.1 to 2.2 µSv/h. At the same locations, results of beta-gamma contamination measurements ranged from 0.01 to 0.28 Megabecquerel/m2.

[ETA This is the first time that no food sample was above limits. On the other hand, I don't see anything about mushrooms or sand lances this time.]

Analytical results related to food contamination were reported by the Japanese Ministry of Health, Labour and Welfare on 11 April, and covered a total of 21 samples taken on 8 April and 10 to 11 April. Analytical results for all of the samples of various vegetables, spinach and other leafy vegetables, fruit (strawberries), various meats (chicken, beef and pork), seafood and unprocessed raw milk in eight prefectures (Fukushima, Gunma, Hyogo, Ibaraki, Miyagi, Niigata, Saitama and Yamagata) indicated that I-131, Cs-134 and/or Cs-137 were either not detected or were below the regulation values set by the Japanese authorities.3. Marine Monitoring

TEPCO Monitoring Programme

TEPCO is conducting a programme for seawater (surface sampling) at a number of near-shore and off-shore monitoring locations.

Until 3 April a general decreasing trend was observed at the sampling points TEPCO 1 to TEPCO 4. After the discharge of contaminated water on 4 April, a temporary increase has been reported.

On 12 April no new data for TEPCO 1 - 10 sampling points have been reported.

MEXT Off-shore Monitoring Programme
As reported in the brief of 8 April MEXT initiated the off-shore monitoring program on 23 March and subsequently points 9 and 10 were added to the off-shore sampling scheme. On 4 April, MEXT added two sampling points to the north and west of sampling point 1. These are referred to as points A and B.

0n 12 April no new data for all MEXT sampling points have been reported.

4. IAEA Activities
In addition to countries that have already been identified in previous briefs, the Philippines and the Republic of Korea have also provided monitoring data and/or links to their websites.

The team of three Agency experts in BWR technology is due back in Vienna today.

Fukushima Nuclear Accident Update (12 April 2011, 04:45 UTC)

The Japanese Nuclear and Industrial Safety Agency (NISA) today issued a new provisional rating for the accident at the Fukushima Daiichi nuclear power plant on the IAEA International Nuclear and Radiological Event Scale (INES).

The nuclear accident at Fukushima Daiichi is now rated as a level 7 "Major Accident" on INES. Level 7 is the most serious level on INES and is used to describe an event comprised of "A major release of radioactive material with widespread health and environmental effects requiring implementation of planned and extended countermeasures". Japanese authorities notified the IAEA in advance of the public announcement and the formal submission of the new provisional rating.

The new provisional rating considers the accidents that occurred at Units 1, 2 and 3 as a single event on INES. Previously, separate INES Level 5 ratings had been applied for Units 1, 2 and 3. The provisional INES Level 3 rating assigned for Unit 4 still applies.

The re-evaluation of the Fukushima Daiichi provisional INES rating resulted from an estimate of the total amount of radioactivity released to the environment from the nuclear plant. NISA estimates that the amount of radioactive material released to the atmosphere is approximately 10% of the 1986 Chernobyl accident, which is the only other nuclear accident to have been rated a Level 7 event.

Earlier ratings of the nuclear accident at Fukushima Daiichi were assessed as follows:

On 18 March, Japanese authorities rated the core damage at the Fukushima Daiichi 1, 2 and 3 reactor Units caused by loss of all cooling function to have been at Level 5 on the INES scale. They further assessed that the loss of cooling and water supplying functions in the spent fuel pool of the Unit 4 reactor to have been rated at Level 3.

Japanese authorities may revise the INES rating at the Fukushima Daiichi nuclear power plant as further information becomes available.

INES is used to promptly and consistently communicate to the public the safety significance of events associated with sources of radiation. The scale runs from 0 (deviation) to 7 (major accident).

 

[dorispulaski]

More NHK news

And another really big aftershock-this was reported on the TEPCO report, too, if you didn't catch it, but it's hard to tell all these quakes apart without a scorecard. It reminds me of this old sign I used to see at work:

"When you're up to your ears in alligators, it's hard to remember that your original goal was to drain the swamp."

Well, maybe it wasn't "ears".

However, Tepco has finally begun to pump out the Unit 2 tunnel, which is where the most highly contaminated water is located.

NHK

Removal of radioactive water beginsThe operator of the crippled Fukushima Daiichi nuclear plant has begun work to remove highly radioactive water after a one-day delay due to a series of earthquakes since Monday.

Tokyo Electric Power Company started transferring radiation-contaminated wastewater from a tunnel outside the Number 2 reactor to a turbine condenser on Tuesday evening.

The radioactive water had been hampering work to restore cooling functions in the damaged reactors.

Earlier in the day, a quake with an intensity of six-minus on the Japanese scale of zero to 7 hit the plant.

The external power supply to the plant remained intact, and injection of water to cool the Numbers 1, 2 and 3 reactors continued.

Injection of nitrogen gas into the Number 1 reactor containment vessel to prevent a hydrogen blast has been continuing without any interruptions.

But the pressure level inside the container has remained flat over the past few days, suggesting that certain gases may be leaking out of the vessel. The power company says there has been no significant change in radiation levels around the plant.

On Tuesday morning, a fire broke out in a seawater sampling facility, but was put out about 7 minutes later.

The plant operator believes a battery short-circuited.
Tuesday, April 12, 2011 21:39 +0900 (JST)

And this:

Aftershocks interrupt work at Fukushima plant

Work to put the crippled Fukushima Daiichi nuclear power plant under control has been repeatedly interrupted by a series of earthquakes since Monday. On Tuesday, a quake with an intensity of six-minus on the Japanese scale of zero to 7 hit near the plant shortly after 2:00 PM local time.xternal power supply to the plant remained intact, and injection of water to cool the Number 1, 2 and 3 reactors continued.
The plant's operator, Tokyo Electric Power Company, was due to use a hose to remove radiation-contaminated wastewater from a tunnel outside the Number 2 reactor to a turbine condenser on Monday. But workers were unable to begin the process as of Tuesday afternoon, pending inspection of the hose for possible leaks.
Injection of nitrogen gas into the Number 1 reactor containment vessel to prevent a hydrogen blast has been continuing without any interruptions.But the pressure level inside the container has remained largely flat over the past few days, suggesting that injected gas may be leaking out of the vessel.
The power company says there has been no significant change in radiation levels around the plant, and is continuing the procedure with caution.

On Tuesday morning, a fire broke out in a seawater sampling facility, but was put out about 7 minutes later. The plant operator believes a battery short-circuited, and is looking for other possible fire hazards.

Tuesday, April 12, 2011 19:04 +0900 (JST)

and more briefings are being given to residents who are being told they might be evacuated in a month. In Kawamata, only some parts of town are to be evacuated.

Kawamata residents briefed on planned evacuation
Officials of a town in Fukushima Prefecture have explained to residents an evacuation plan amid increasing risks of radiation released by the crippled Fukushima Daiichi nuclear power plant.

Kawamata Town Mayor Michio Furukawa met about 40 people living in the southeastern part of the town, which is in a newly-designated evacuation zone.

Japan's government on Monday expanded the zone to locations where annual exposure to radiation is expected to exceed 20 millisieverts.

Furukawa said the residents will be sheltered in public facilities in safe areas of the town and that temporary houses for evacuees will also be built.

A resident said the town should clarify how long the evacuation will last. Another said he will not leave his home until compensation is made for his livestock.
Tuesday, April 12, 2011 20:51 +0900 (JST)

 

[Olympia]

Thanks, Doris. I hope none of the aftershocks complicate the cleanup.

And rats! The nitrogen could be leaking out of the number 1 reactor? Rats!

 

[dorispulaski]

Olympia, The good thing about Unit 1 is that it is cooling slowly back down. And the pressure is rising very slowly. If it rose quickly, they'd have to vent.

9:00 AM April 13 TEPCO Report

Radiation Monitoring

TEPCO has redone their website, and I am having difficult finding things, but on the good side, you can see exactly where measurements are taken, because there is a site map. There is also a trend chart. You can see that the highest 3 measurement point values are closest to Units 1 through 3.
9:00 AM April 13th graph & data:
http://www.tepco.co.jp/en/nu/fukushima-np/f1/index-e.html

They have also started reporting 7 measurement sites at Daini, in the same format
9:00 AM April 13th graph & data:
http://www.tepco.co.jp/en/nu/fukushima-np/f2/index-e.html

You can see that measurement points One and Three are closest to Daiichi
(3.1, 2.3, 3.3, 2.6, 2.6, 2.6) microSieverts per hour at 9:00 AM on April 13th


The wind was in the South at 9:00 AM April 13th
Daiichi Gamma Radiation
West Gate 39.8 microSieverts per hour
Main Office Building 0.57 milliSieverts per hour
Main Gate 75 microSieverts per hour
West Gate 32 microSieverts per hour

8 peripheral measurement points (11, 37, 35, 34, 62, 102, 218, 187) microSieverts per hour

12:00 Noon Status Report for April 13th:

-From 7:35 pm, April 12th, we started transferring the high level radioactive puddle water in the trench of the turbine building to the condenser by an underwater pump.

Operation for cooling the spent fuel pools -From 0:30 am to 6:57 am on April 13th, we conducted water spraying to Unit 4 by the concrete pumping vehicle.

From 4:26PM, April 12th, we began spraying water to the spent fuel pool of Unit 3 by a concrete pumping vehicle and finished at 5:16PM, April 12th.

* From 0:30AM, April 13th, we began spraying water to the spent fuel pool of Unit 4 by a concrete pumping vehicle and finished at 6:57AM, April 13th.

* From 7:35PM, April 12th, we began transferring puddle water in the trench of Unit 2 to the condenser of Unit 2.

They continue to work on preventing leakage from the site into the sea. Here's what they have done so far:

On April 6, 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 5, 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. In order to prevent water containing radioactive materials from spilling from a plant's port to the sea, we installed 120 meter wide double silt fences around a breakwater on the south of the station at 10:45 am on April 11. From April 12th, we are working on installing an iron plate in front of the screen of Unit 2

Spraying fixative

1,200 m2 on April 11 and approx. 700 m2 on April 12 on a trial basis

NHK has several reports:

TEPCO has truly started pumping the water out of the trenches at Unit 2. And someone was actually able to get to the Unit 4 spent fuel pool to take a water sample. Given that the radiation at the water surface is 81 milliSieverts per hour, it's obvious that there is a mess in that pool, and that fuel there has been damaged, but we already knew that, considering they had a fire there. Twice. It's all blurring a bit now, but wasn't that the pool that the head of the US NRC swore there was no water in at one point, and that the pool wouldn't hold water? I suppose the fact that there is actually water in the pool is at least better than that. NHK has glommed several stories into one in this piece.

Contaminated water level falls 4 cm

The operator of the crippled Fukushima Daiichi nuclear power plant says the level of contaminated water in the tunnel of the No. 2 reactor has dropped 4 centimeters.

Tokyo Electric Power Company says workers at the plant had moved about 250 tons of highly radioactive water from the tunnel into a turbine condenser by Wednesday morning.

It says that as a result, the water level had dropped by 4 centimeters to 95 centimeters below the surface as of 7 AM.

A series of aftershocks delayed the start of the work until after 7:30 PM on Tuesday. TEPCO says it is expected to take about 40 hours to move a total of 700 tons of contaminated water from the tunnel.

The company has been checking another storage facility for damage in order to use it for contaminated water from the basement of the reactor's turbine building.

These efforts are aimed at allowing workers to restore the reactor's cooling system.

TEPCO also says it injected nearly 200 tons of water into the spent fuel storage pool at the No. 4 reactor early Wednesday.

It says an analysis of the water from the pool on Tuesday put the radiation level on the surface at 84 millisieverts per hour and the water temperature at around 90 degrees Celsius, higher than usual.

The company says it will try to identify radioactive substances in the water in the pool and their densities to determine whether the reactor's fuel has been damaged.
Wednesday, April 13, 2011 12:47 +0900 (JST)

This from the EU. This makes me bang my head on the wall. The EU is going to lower its limits on Japanese foods vis a vis European foods. However, note what the limits on cesium and strontium are.


http://www.dbune.com/news/world/5346-eu-mulling-tighter-radiation-limits-on-japanese-foods.html

EU Health Commissioner John Dalli's spokesman Frederic Vincent said that the bloc is keen on bringing its current radiation limits of caesium-134 and cesium-137 in line with those of Japan - a move that is aimed at reducing permissible contamination level to 500 becquerels per kg. Presently, the contamination level is at 1,250 becquerels per kg.

The new limit will set iodine-131 at 2,000 becquerels per kg and strontium-90 at 750 becquerels per kg. In the meantime, the EU has urged Japan to check for radiation in all of its food exports.

Meanwhile, NHK reports some strontium has been found in Iitate Village and Namie from samples taken between March 16th and March 19th.

I'm not sure who the expert is, but once the material had gotten to Iitate and Namie, it stayed there. Strontium has a long half life. All you can be sure is that it was deposited prior to the sample being taken. My guess is the Unit 2 suppression pool explosion, or perhaps the fires in the spent fuel pool. If you look at the data from air counts from Iitate, the big spike occurs between the 15th and the 16th and drops off after that. (see p. 2 for the graphs). As to how much this is, like the plutonium next to the buildings in Daiichi itself, enough to show that stuff came out of the interior of a reactor, but 30 Becquerels of strontium per kg in food would still be acceptable to eat, either in Japan or the EU.


Here's the JAIF trend charts which have Iitate shown (see page 2)
http://www.jaif.or.jp/english/news_images/pdf/ENGNEWS01_1302661803P.pdf

Radioactive strontium detected outside 30km zone

Japan's science ministry says small amounts of radioactive strontium have been detected in soil and plants outside the 30-kilometer zone around the Fukushima plant where the government has advised people to stay indoors. Strontium could cause cancer.

The ministry has been monitoring the level of radioactive substances in soil and weeds in Fukushima Prefecture.

It found 3.3 to 32 becquerels of strontium 90 per kilogram of soil in samples taken from 3 locations in Namie Town and Iitate Village, 30 kilometers from the plant.

An extremely small amount of strontium was also found in plants taken from Motomiya City, Ono Town and Otama and Nishigo Villages. The areas are 40 to 80 kilometers from the Fukushima plant.

Strontium 90 has a half-life of 29 years. It tends to accumulate in bones and could cause cancer.

The ministry says the amount found is extremely low and will not have a negative health impact even if a person ingested one kilogram of the contaminated soil.

The samples were taken between March 16 and 19.

A nuclear engineering expert says the fact that strontium was detected proves that the fuel in the reactor or the spent fuel in the pool was damaged at that point. He says a hydrogen explosion occurred at Reactor 3 around that time and the particles may have been carried by winds.
Wednesday, April 13, 2011 07:52 +0900 (JST)

This is the NHK report of the data that TEPCO posted early yesterday morning

High radiation levels in sea off Fukushima coast

The science ministry says radiation levels in seawater off the coast of Fukushima Prefecture are the highest since it began monitoring them about 3 weeks ago.

The ministry says the level of iodine-131 was 88.5 becquerels per liter in a sample taken on Monday in the sea about 30 kilometers east of the Fukushima Daiichi nuclear plant. The figure is 2.2 times the government's upper limit for wastewater from nuclear facilities.

The level of cesium-137 was also the highest observed so far, but was below the limit.

Tokyo Electric Power Company says the iodine-131 level was 23 times the upper limit in a sample taken 15 kilometers from the plant.

This was the highest figure since TEPCO began taking samples 15 kilometers offshore on April 2nd.

Radiation levels are higher in the sea to the north of the crippled plant.

The government's Nuclear and Industrial Safety Agency says radioactive substances seem to be flowing and diffusing northward.

The agency says predicting the course of the flow is difficult and it will step up monitoring in locations where high radiation levels have been detected.
Wednesday, April 13, 2011 09:04 +0900 (JST)

 

[dorispulaski]

Meanwhile, the NEI wants to discuss the differences between Chernobyl and Daiichi. They've made a fact sheet. I will not quote it all, but here's a piece:

http://resources.nei.org/documents/japan/FactSheet_Chernobyl_Fukushima_4-12-11.pdf

The uncontrolled release of Chernobyl reactor’s fission products was exacerbated by the failure of Soviet authorities to take immediate action to protect surrounding populations. By contrast, the Japanese authorities took early steps to evacuate people, distribute potassium iodide, and restrict the transport and sale of food from the region.

• The Chernobyl accident left the area in a 30-kilometer radius around the facility as a long-term
restricted zone. It is unlikely that any significant areas of land in Japan will have long-term restrictions...

Long-Term Health Effects

The unique nature of the Chernobyl accident resulted in widespread airborne dispersion of radioactive cesium as fallout, which has a half-life of 30 years. The incident left the area in a 30- kilometer radius around the facility as a long-term restricted zone.
....
Although measurements of radioactivity in the air and water near the Fukushima plant have been evident at varying levels, wide dispersion of radioactive materials has not occurred at the facility. While there may be localized spots that will require monitoring and remediation, it is unlikely that any significant areas of land in Japan will have long-term restrictions.

I do hope they are right about that.

But it might be a good time to discuss remediation.

 

[dorispulaski]

The US Government has been in the remediation business for some years, and an expensive business it is. During the years of the Cold War, and the Manhattan Project prior to that, the US was turned into one huge weapons factory. There are all sorts of contaminated sites.

Also they performed a Hydrogen Bomb test at Bikini Atoll in the Marshall Islands, and the Marshall Islanders want the areas made habitable again.

http://www.bikiniatoll.com/whatrad.html

There is also an IAEA report on the subject.

The main thing that needs to be fixed on Bikini is the cesium level. The sea has long since diluted the pollution in the lagoon to where there is no problem with it. However, there is still a significant cesium concentration on land (not surprising. The half life is 30 years.)

The potassium fertilizer approach for fields, coupled with clean up around houses and yards would work for most areas.

Also, I wouldn't raise mushrooms for sale.

Bikini Atoll
5. Several possible remediation strategies were considered with the result that the following were selected as a basis for further assessment:


*The periodic application of potassium based fertilizer to all areas of Bikini Island where edible crops may be grown, supported by the removal of soil from around and beneath the dwelling areas and its replacement by crushed coral (known as the potassium fertilizer remediation strategy);

*The complete removal of the topsoil from Bikini Island (called the soil scraping remediation strategy) .

While no definite recommendations are given on which strategy to follow, it is considered that the strategy using potassium fertilizer is the preferred approach.

In this connection, it was noted that the soils of Bikini Atoll are extremely deficient in potassium and extensive field trials have demonstrated that the application of potassium rapidly reduces the concentration of l37Cs in food crops since potassium is taken up by the plants in preference to caesium. The reduction of 137Cs in the food crops is sustained for about four to five years, after which the values slowly begin to increase again. However, repeated application of fertilizer forms an effective strategy in reducing the estimated doses to the potential inhabitants of Bikini Island. Furthermore, the supporting strategy of removing soil from dwelling areas would eliminate most of the external and internal exposures from direct soil ingestion or inhalation.

6. It is concluded that:
The results expected from the potassium fertilizer remediation strategy are consistent with international guidance on interventions to avoid dose in chronic exposure situations and, therefore, this strategy would provide a radiologically safe environment permitting early resettlement.

Depending on the assumptions made concerning diet, ... The doses will be somewhat higher than those due to natural background radiation that were incurred by the inhabitants of Bikini Island before the evacuation and prior to when the nuclear weapon tests took place, and also somewhat higher than global average natural background doses, but lower than typical elevated levels of natural background doses around the world.

7. The conclusion is that:
The alternative strategy, i.e. the soil scraping remediation strategy-stated to be the alternative preferred by the Bikinians-would be very effective in avoiding doses caused by the residual radionuclides, but it could entail serious adverse environmental and social consequences.
The consequences may be serious because the fertile topsoil supports the tree crops, which are the major local food resource. The replacement of the soil with topsoil from elsewhere would be an enormous undertaking which is likely to be prohibitively expensive. The content of natural radionuclides in any continental soil used as replacement soil would most probably exceed that of the present soil....

that the proposed remediation strategy is undertaken, it is further recommended that:
Regular measurements of activity in local foodstuffs should be made to assess the effectiveness of the measures taken. A simple, local whole body monitor and training in its use should be provided as a further means of enabling potential inhabitants to satisfy themselves that there is no significant uptake of caesium into their bodies.
*Copies of the full IAEA report may be ordered from [email protected]

 

[dorispulaski]

In areas where cesium needs to actually be removed from the soil, people have had some ideas over the years. Water leaches cesium out of soil, and cesium sorbs to clay, furthermore any plant that is naturally high in potassium will accumulate cesium - mushrooms, certain trees and berry bushes, sunflowers, bananas, oranges for example. Farmers should choose to grow plants that don't take up cesium by preference:

http://gsa.confex.com/gsa/2007AM/finalprogram/abstract_129848.htm
REMEDIATION OF URANIUM AND CESIUM CONTAMINATED SOILS BY USING SOIL WASHING PROCESSLEE, Minhee, CHANG, Youngjin, and YANG, Minjun, Environmental Geosciences, Pukyong National University, 599-1 Daeyondong Namgu, Busan, 608-737, South Korea, [email protected]


Hanford Remediation description (the US huge weapons laboratory and weapons producing complex:
http://www.hanford.gov/page.cfm/SoilGroundwater

http://www.google.com/#sclient=psy&...=1&bav=on.2,or.r_gc.r_pw.&fp=e7df6ea8d325b7b2

KUNBERGER, TANYA MARIE KING. Remediation of Soil – Sorbed Cesium Through the
Process of Clay Fines Dispersion and Piping. (Under the direction of Dr. M. A. Gabr.)

 

[dorispulaski]

April 14th, 9:00 PM Radiation Reports
Daini Six Periphery Measuring Points (3.0, 2.2, 3.2, 2.5, 2.5, 2.5) microSieverts per hour

Daiichi Gamma Radiation from Cart
West Gate 38.2 microSieverts per hour, wind in the south

Daiichi Temporary Measuring Points
Main Building 0.55 milliSieverts per hour
Main Gate 73 microSieverts per hour
West Gate 30 microSieverts per hour

Eight Fixed Periphery Points (11, 37, 34, 33, 61, 99, 216, 186) microSieverts per hour

Graphs of materials in the air at Daiichi:
http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110413e9.pdf
No significant change: things vary at this level due to things like running trucks around the site or not, particularly particulate levels (i.e. dust levels). Levels for iodine and cesium in the air are 10% or less of the regulatory amount for radiation workers.

Daini Levels are still slowly dropping.
Cesium levels for both particulate and volatile materials are now below their level of detection, as of Apr 13th.http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110413e10.pdf


Seawater Monitoring; Data for April 12thhttp://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/110413e7.pdf

Concentrations at the North and South discharge canals have dropped down to about 1 Becquerel per cubic centimeter, which is about what is being seen in the 15 km offshore samples in previous days: (I think this is very good news.)

North 0.72 Becquerels per cubic centimeter of I 131
0..90 Becquerels per cubic centimeter of Cs 134
0.86 Becquerels per cubic centimeter of Cs 137
South Discharge Canal
1.7 Becquerels per cubic centimeter of I 131
1.8 Becquerels per cubic centimeter of Cs 134
1.8 Becquerels per cubic centimeter of Cs 137
Yesterday's seawater sampling surveys at 6 locations 15 km off the coast of Fukushima Daiichi Nuclear Power Station were deferred due to bad weather.

TEPCO says in its 6:00 PM Status for Daiichi for April 14th:

Spent Fuel Pools

-At 1:15PM, April 13th, we started injecting fresh water to Unit 2 by a temporary motored pump and finished at 2:55PM of the same day

JAIF says in the April 14th report

situation. Highly radioactively contaminated ｗafter accumulated inside trench for piping outside the building is being transferred to the condenser at Unit 2 as of Apr. 13. it is confirmed water level in the trench goes down since transportation started.

So they can pump out and keep ahead of leaking water, and perhaps get things dry enough that they can repair the cooling system to Unit 2, and its associated spent fuel pool. However, they have to keep finding places to put the water. Fortunately they have 2 US barges and a number of tanks on order. Also I understand they are in discussions with Russia to obtain the services of the ship used to deal with radioactive water, when they decommission Russian submarines.

TEPCO also has its 4:00 PM Status for April 14th for all its nuclear plants up:

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)

* At 1:15PM, April 13th, we started injecting fresh water to Spent Fuel Pool of Unit s from Fuel Pool Cooling line and finished at 2:55PM of the same day
*From 7:35PM on April 12, we started transferring accumulated water in Turbine Building from the trench of Unit 2 to the condenser. At 11:00AM on April 13, we stopped transferring accumulated water to check whether there was water leakage from condenser or not. We didn't find any problem, so we restarted transferring at 3:02PM of the same day.

* In order to prevent water containing radioactive materials from spilling from a plant's port to the sea, we installed 120 meter wide double silt fences around a breakwater on the south of the station at 10:45 am on April 11. On April 12th and 13th, we installed three iron plates in front of Unit 2 screen. At 1:50pm on April 13th , we installed a silt fence in front of Unit 3 and 4 screen.

*At 11:00am on April 13th , we started spraying inhibitor in order to prevent diffusion of radioactive materials on a trial basis and finished at 11:30 am of the same day.

* 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 and on April 12, we found there was no contamination inside the body.

TEPCO says that their Kashiwazaki-Kariwa Nuclear Power Station found trace amounts of Cesium 137 and Cesium 134, and will continue monitoring, including amounts in pine needles, soil, pine needles, and so forth as Kashiwazaki-Kanwa. Amounts they found there of Cs 137 are the four millionth part of the limit, and Cs 134 was 1 three millionth of the limit.
http://www.tepco.co.jp/en/press/corp-com/release/11041305-e.html

Additionally, TEPCO has been requested by the government check, and if necessary, to reinforce, Daiichi for seismic safety
http://www.tepco.co.jp/en/press/corp-com/release/11041306-e.html

The Ministry orders you to report the following matters pursuant to Section 67.1 of Act on the Regulation of Nuclear Source Material, Nuclear Fuel Material and Reactors (Act No.166 of 1957).
If you disagree with this decision, you may raise an objection to the Minister of Economy, Trade and Industry within sixty days from the day following the date when you learn that the decision was made under Article 6 of Administrative Dissatisfaction Inspection Act (Act No. 160 of 1962). However, you may not raise an objection after one year has passed since the following date of the decision even if it falls within sixty days from the day following the date when you learn that the decision was made.

(Instructions from Ministry of Economy, Trade and Industry)
·Results of the earthquake-proof safety evaluations of primary containment vessels and reactor pressure vessels which are important facilities for the earthquake-proof safety, and reactor buildings which are indirect supporting structures for spent fuel pools at Fukushima Daiichi Nuclear Power Station using the possible earthquakes in the future for the input earthquake motion.·Results of the studies of countermeasures such as antiseismic reinforcement work to the places where the earthquake-proof safety might not be secured in the current reactor buildings.

How High Was the Tsunami at Daini and Daiichi?

On April 9th, TEPCO furnished more data, from photographs and a phone video of the tsunami at Daiichi, made by an employee who was fleeing the tsunami, to NISA. NISA responded, and wants TEPCO to do more analysis. Now I would have thought that the Japanese equivalent of the US Coast & Geodetic Survey or NOAA or else the tsunami prediction group that apologized for inaequate warnings the other day would be doing this. However, its TEPCO, in the spare time they have between 3 reactors incidents, 4 spent fuel pool incidents, corralling of radioactive water, pacifying the insatiable lust of the media and foreign governments for information, and going 15 km to 30 km out to see to collect sampling data from buoys. (Rant over)

We, Nuclear and Industrial Safety Agency (hereinafter called "NISA") have judged that specific analysis and evaluation on tsunami with re-creation calculation in both power stations based on results of the investigation regarding tsunami generated by this earthquake are necessary.
That is why NISA requires TEPCO to analyze and evaluate the things as below, and to report by July 8th, 2011.
In addition, it is necessary for research and review for the things as below to be implemented in consideration of radiation influence to workers.
*Remark
1. Data arrangement on tsunami trace inside and outside of the power station site
In order to analyze the particularity and the influence of tsunami to both stations, it is necessary to record and arrange the data on tsunami trace as precisely as possible. The detail is as follows:
-improvement on accuracy to estimate the height of tsunami and inundation area
-movement of the bottom of the ocean floor in front of the power station site
-ground deformation under the power station site (ground subsidence)
-Situation of floating wreckage (size, weight, distance)
-Damage situation in buildings and civil engineering structure (including inundation)

2. Analysis of particularity and influence of tsunami to both power
stations
In addition to re-creation calculation of tsunami, based on the results, it is necessary to analyze particularity and influence of tsunami generated by this earthquake to both power stations. The detail is as follows:
-analysis on the direction that tsunami came from, inundation channel and process inside the power station site
-analysis on influence to the facility by tsunami (influence from leading wave and stern wave and from floating wreckage)
-analysis on the water channel in case the nuclear reactor building and turbine building are inundated and on influence to importance facility with regard to seismic safety

NHK News I missed:

●China demands information on nuclear crisis

Chinese Premier Wen Jiabao has urged Japan's leader to disclose all necessary information on the crisis at the Fukushima Daiichi nuclear power plant. Wen spoke with Japan's Prime Minister Naoto Kan in a telephone conference on Tuesday for the first time since the March 11th disaster.

Kan expressed appreciation for China's aid following the disaster. Wen said he thinks of the disaster as though it happened in China. He added China believes the Japanese government and people will overcome the current hardship and reconstruct the stricken areas. Kan also pledged to maintain full transparency in providing information on the nuclear crisis. Wen responded that China hopes the Japanese government will be able to contain the accident effectively.

Wen and Kan also agreed to strengthen cooperation on nuclear safety and disaster prevention measures, as next year will mark the 40th anniversary of the normalization of diplomatic ties between the 2 nations.
Tuesday, April 12, 2011 21:12 +0900 (JST)

●China wants accurate information on radiation

China has urged Japan to provide information accurately and swiftly regarding radioactive contamination caused by the accident at the crippled Fukushima Daiichi nuclear power plant.Chinese Foreign Ministry spokesperson Hong Lei spoke to reporters on Tuesday, following Japan's announcement that the crisis level at the plant was raised to 7 -- the highest on an international standard. Hong said China is looking at the announcement carefully.

Last Friday, China expanded its ban on imports of Japanese farm and marine products from 5 prefectures to 12, including Tokyo. China's government says it will continue to monitor developments at the plant and radioactive contamination.
Tuesday, April 12, 2011 20:26 +0900 (JST)

●IAEA calmly reacts to Fukushima plant's level 7

The International Atomic Energy Agency says it has been notified by Japan that it raised the crisis level at the crippled Fukushima Daiichi nuclear power plant to 7 -- the highest on an international scale. In a statement released on Tuesday, the UN organization said Japan reevaluated the rating based on its estimate of the total amount of radioactivity released into the environment. It said Japan's nuclear safety agency calculated that the amount of radioactive material released into the atmosphere is about 10 percent of that in the 1986 Chernobyl accident.

IAEA member countries are reportedly reacting calmly to Japan's decision to raise the level, due to a shared view about the seriousness of the accident based on information provided by Japan's government. The members also reportedly knew that many international research organizations had said the accident should be assessed as a level-7 crisis.
Tuesday, April 12, 2011 20:15 +0900 (JST)

●Japan, S.Korea discuss radiation safety

South Korea has expressed deep concern about Japan raising the severity of its nuclear disaster to the highest level on Tuesday. South Korea's foreign ministry spokesperson told reporters in Seoul that the government is very sorry to see that the crisis is far from over. The rating of the
accident at the Fukushima Daiichi nuclear plant was raised from 5 to 7, the worst on an internationally recognized scale. The spokesperson disclosed that experts from Japan and South Korea started 2- days of talks in Tokyo on Tuesday about the radiation release from the
Fukushima plant. He said South Korea wants to obtain accurate information from Japan, as radiation fears are spreading among South Koreans, who have stopped buying marine products.
Tuesday, April 12, 2011 18:36 +0900 (JST)

●Overseas media make quick report on raising level

Overseas media were quick to report on Japan's raising of the severity of a nuclear accident at the crippled Fukushima Daiichi power plant to the worst level on an internationally recognized scale.

The AP news agency reported on Tuesday that Japan's authorities raised the level of the crisis to rank it on par with the 1986 Chernobyl disaster. The Reuters news agency reported that the worst "level 7" rating reflects a serious situation that has continued since the outbreak of the accident, meaning that the situation has not suddenly become more critical. The British broadcaster BBC, and US television network CNN also reported the rise in the level, live from Tokyo.
Tuesday, April 12, 2011 18:36 +0900 (JST)

●Edano: No need to change Fukushima response

Japan's top government spokesman says there will be no change in the way the crisis at the Fukushima Daiichi nuclear power plant is being handled.Chief Cabinet Secretary Yukio Edano on Tuesday held his first news conference for the international media since the March 11th earthquake and tsunami.

Most questions from reporters focused on the government's decision to raise the severity level at the Fukushima plant to 7 from 5. Level 7 is the highest rank on an international scale and was also applied to the 1986 Chernobyl accident. Edano stressed that raising the crisis level does not mean the situation is worsening. He said the upgrade was not due to a new emergency, but is based on the latest analysis of data.

A correspondent for a British magazine, the Economist, said Japanese ministers need to send more information to the world through foreign media outlets.The correspondent said that politicians should have made more media appearances immediately after the disaster.
Wednesday, April 13, 2011 03:18 +0900 (JST)

●Govt to do utmost to control Fukushima

Japan's industry minister says the government will do all it can to quickly put the crippled Fukushima Daiichi nuclear power plant under control. Banri Kaieda was speaking to reporters on Tuesday after his ministry's nuclear safety agency raised the crisis level of the plant to 7 -- the highest level on an international scale.

Kaieda said the level is equivalent to that of the 1986 Chernobyl disaster, but that the volume of radiation from Fukushima is about one-tenth that at Chernobyl. He added, however, that he fears the amount of radiation leaked into in the environment will increase, as workers at Fukushima have yet to stop the release of radioactive substances.
Tuesday, April 12, 2011 18:36 +0900 (JST)

●TEPCO removing toxic water at Fukushima plant

Tokyo Electric Power Company is removing highly radioactive water at the crippled Fukushima Daiichi nuclear plant. The work had fallen behind schedule due to a series of aftershocks on Monday and Tuesday. Workers started transferring the toxic water from a tunnel outside the Number 2
reactor to a turbine condenser on Tuesday evening. TEPCO estimates 6,000 tons of contaminated water has accumulated in the tunnel.

The company hopes to complete pumping 700 tons around Thursday noon. Workers will then begin removing toxic water from the reactor's basement. Radioactive water flooding the tunnels and basements of the turbine buildings at Reactors 1 through 3 is getting in the way of restoring their cooling functions. Separately, TEPCO has been injecting nitrogen gas into the Number 1 reactor containment vessel to prevent a hydrogen blast. But the pressure level inside hasn't gone up, suggesting that gases may be leaking outside. The company says it will monitor radiation levels around the plant. [ETA: The pressure is going up,but very slowly, as they are adding nitrogen. Temperature dropped on April 13th at the Reactor Pressure Vessel to 204.5 C at the feed water line nozzle. This is down over 30 C from what it was a week ago.)

The power company is also analyzing a water sample taken from Reactor 4's spent fuel pool on Tuesday. It says the water temperature was higher than usual at 90 degrees Celsius. Radiation around the pool was also high at 84 millisieverts per hour. TEPCO says it will pump water into the pool until it is full.
Wednesday, April 13, 2011 07:53 +0900 (JST)

 

[dorispulaski]

IAEA Update April 13th

IAEA Briefing on Fukushima Nuclear Accident (13 April 2011, 14:30 UTC)
Presentations:
→ Summary of Reactor Status


1. Current Situation

Overall, the situation at the Fukushima Daiichi plant remains very serious but there are early signs of recovery in some functions such as electrical power and instrumentation

There have been no changes concerning the provisional INES Level 7 rating and protective measures as reported in yesterday's brief.

Earthquakes of 11th and 12th April

The IEC received information from the IAEA International Seismic Safety Center on the following recent earthquakes (equal or higher than magnitude Mw= 6.0) which occurred in the time interval from 23:08 UTC on 2011-04-11 to 05:07 UTC on 2011-04-12:

1) At 23:08 UTC, 2011-04-11, an earthquake with a magnitude of 6.2 occurred offshore of the East Coast of Honshu, Japan) at a depth of 13.1 km. Distances from epicentre of the earthquake to NPP sites were: 188 km to Tokai, 217 km to Fukushima Daini, 229 km to Fukushima Daiichi, 236 km to Hamaoka and 285 km to Kashiwazaki-Kariwa.

2) At 05:07 UTC, 2011-04-12, an earthquake with a magnitude of 6.0 occurred inland east of Honshu, Japan at a depth of 10.6 km. Distances from epicentre of the earthquake to NPP sites were; 46 km to Fukushima Daini, 53 km to Fukushima Daiichi, 72 km to Tokai, 165 km to Onagawa and 179 km to Kashiwazaki-Kariwa.

NISA press release regarding the earthquake which occurred on 12th April, states that there was no effect on the following NPP sites: Fukushima Dai-ichi, Fukushima Dai-ni, Tokai Dai-ni, Onagawa. Other nuclear related facilities (Mitusubishi Nuclear Fuel, Nuclear Fuel Industries Ltd., JAEA Tokai & its recycling plant) in Tokai area were reported to be safe by their respective operators.

Changes to Fukushima Daiichi Plant Status

On 11th April, a fire broke out in the housing outlet structure for cooling water for Units 1-4. The fire was extinguished manually. No consequences were identified in terms of release of radioactive material, cooling of the plants, or values recorded by radiation monitoring posts.

In Unit 1 fresh water is being continuously injected into the RPV through the feed-water line at an indicated flow rate of 6 m3/h using a temporary electric pump with off-site power. In Units 2 and 3 fresh water is being continuously injected through the fire extinguisher lines at an indicated rate of 7 m3/h using temporary electric pumps with off-site power.

Nitrogen gas is being injected into the Unit 1 containment vessel to reduce the possibility of hydrogen combustion within the containment vessel. The pressure in this containment vessel has stabilised. The pressure in the RPV is increasing as indicated on one channel of instrumentation. The other channel shows RPV pressure as stable.

In Units 2 and 3 Reactor Pressure Vessel and Drywell pressures remain at atmospheric pressure.

RPV temperatures remain above cold shutdown conditions in all Units, (typically less than 95°C). In Unit 1 temperature at the feed water nozzle of the RPV is 206°C and at the bottom of the RPV is 119°C. In Unit 2 the temperature at the feed water nozzle of the RPV is 165°C. The temperature at the bottom of RPV was reported as 208°C (this measurement has been available since the 12th April). In Unit 3 the temperature at the feed water nozzle of the RPV is 99°C and at the bottom of the RPV is 116°C.

There has been no change in status in Units 4, 5 and 6 and the Common Spent Fuel Storage Facility.

2. Radiation monitoring

On 12th April, deposition of both iodine-131 and cesium-137 was detected in 7 and 6 prefectures respectively. The values reported for iodine-131 ranged from 1.6 to 460 Bq/m2 and for cesium-137 from 31 to 700 Bq/m2. The highest deposition was observed in the Ibaraki prefecture.

Gamma dose rates are measured daily in all 47 prefectures, the values tend to decrease. For Fukushima, on 12th April a dose rate of 2.1 μSv/h, for the Ibaraki prefecture a gamma dose rate of 0.14 μSv/h was reported. The gamma dose rates in all other prefectures were below 0.1 µSv/h.

Only in a few prefectures, iodine-131 or cesium-137 is detectable in drinking water at very low levels. As of 12th April, a restriction for infants related to iodine-131 (100 Bq/l) is in place as a precautionary in a small scale water supply in one village of the Fukushima prefecture.

MEXT reported on measurements of strontium-89 (half-life: 50.5 days) and strontium-90(half-life: 28.8 years) in three samples taken in one village in the Fukushima prefecture on 16 March. The activities in soil for Sr-89 ranged from 13 and 260 Bq/kg and for Sr-90 between 3.3 and 32 Bq/kg. Sr-90 was also distributed globally during nuclear weapons' testing in the atmosphere, typical global levels of Sr-90 in surface soils are in the order of one to a few becquerel per kg. Strontium was also measured in plant samples in four others villages, with values ranging from 12 to 61 Bq/kg for Sr-89 and 1.8 to 5.9 Bq/kg for Sr-90.

On 12th April, the IAEA Team made measurements at 7 different locations in the Fukushima area at distances of 32 to 62 km, North and Northwest from the Fukushima nuclear power plant. At these locations, the dose rates ranged from 0.6 to 1.6 µSv/h. At the same locations, results of beta-gamma contamination measurements ranged from 0.6 to 1.7 Megabecquerel/m2.

NISA reported on 12th April that the three workers who had previously been exposed to high dose rates while working in the turbine building of Unit 3 have undergone further medical checks. No negative outcomes were identified. In the case of the two workers who received doses of a few Sievert to their legs as a result of walking in contaminated water, medical tests showed no evidence of either skin burns or erythema.

Analytical results related to food contamination were reported by the Japanese Ministry of Health, Labour and Welfare on 12th April that covered a total of 55 samples taken on the 8th and 10th -- 12th April. Analytical results for 53 of the samples of various vegetables, fruit (strawberry), seafood and unprocessed raw milk in eight prefectures (Chiba, Fukushima, Gunma, Ibaraki, Kanagawa, Niigata, Saitama and Yamagata) indicated that I-131, Cs-134 and/or Cs-137 were either not detected or were below the regulation values set by the Japanese authorities. In Ibaraki prefecture for samples taken on 11th April, one sample of seafood (sand lance) was above the regulation values set by the Japanese authorities for I-131 and one sample of spinach was above the regulation values set by the Japanese authorities for Cs-134/Cs-137.

On 13th April, the Prime Minister of Japan requested the Governor of Fukushima prefecture to restrict the consumption of shiitake mushrooms (grown on logs in open fields only) produced at Iitate-village until further notice. Instructions were also issued to restrict the distribution of shiitake mushrooms (grown on logs in open fields only) produced in the cities of Date, Soma, Minamisoma, Tamura and Iwaki; the towns of Shinchi, Kawamata, Namie, Futaba, Ookuma, Tomioka, Naraha and Hirono, and; the villages of Iitate, Katsurao and Kawauchi until further notice.

3. Marine Monitoring
TEPCO Monitoring Programme

TEPCO is conducting a programme for seawater (surface sampling) at a number of near-shore and off-shore monitoring locations (see Map1. TEPCO Seawater Sampling Locations).

On same days, two samples were collected at the same sampling point, a few hours apart and analysed separately.

Until 3rd April a general decreasing trend was observed at the sampling points TEPCO1 to TEPCO4. After the discharge of contaminated water on 4th April, a temporary increase has been reported.

On 13th April new data for samples collected on 11th April at TEPCO1-10 sampling points have been reported. As for the near-shore stations TEPCO1, 3 and 4 levels of I-131 and Cs-137 below 1.5 kBq/l have been reported. At TEPCO 2, for both I-131 and Cs-137 concentrations of about 7 kBq/l were measured.

As for the six TEPCO stations 15 km offshore, at TEPCO 5-6-10 the concentration of I-131 was below 0.3 kBq/l and that of Cs-137 below 0.2 kBq/l. At TEPCO 7 and 8, I-131 and Cs-137 below 0.05 kBq/l below 0.02 kBq/l were measured. At TEPCO 9 concentrations of about 1 kBq/l of both I-131 and Cs-137 were recorded.

MEXT Off-shore Monitoring Programme
MEXT initiated the off-shore monitoring program on 23rd March and subsequently points 9 and 10 were added to the off-shore sampling scheme. On 4th April, MEXT added two sampling points to the north and west of sampling point 1. These are referred to as points A and B (see Map2: MEXT Seawater sampling Locationsc).

On 13th April new data for samples collected on 11th April at MEXT 2, 4, 6, 8, 10 an B sampling points have been reported.

Cs-137 was only detected at MEXT 4 at a concentration level of about 70 Bq/l.

I-131 concentration of about 90 Bq/l was measured at Station MEXT4. At MEXT6, 8, 10 and B, I-131 below about 15 Bq/l was reported.

Map 1: TEPCO Seawater Sampling Locations:

http://www.iaea.org/newscenter/images/seawater-sampling-2-100411.jpg

Map 2: MEXT Seawater Sampling Locations:

http://www.iaea.org/newscenter/images/seawater-sampling-2-100411.jpg

4. IAEA activities

No new activities to report.

NEI 10 AM April 13th Eastern Daylight Time update

UPDATE AS OF 10 A.M. EDT, WEDNESDAY, APRIL 13:
Workers at the Fukushima Daiichi nuclear power plant are pumping radioactive water from the concrete enclosure near reactor 2 into a turbine condenser. A series of aftershocks that rattled the area Tuesday has put the work behind schedule. Tokyo Electric Power Co. (TEPCO) is inspecting another storage facility on the site to determine if it can hold contaminated water from the basement of the reactor 2 turbine building. Radioactive water in the turbine buildings is hampering efforts to restore cooling operations at the plant.

TEPCO continues to inject cooling water into reactors 1, 2 and 3 and to spray water as needed into the used fuel pools for reactors 1-4. TEPCO also continues injection of nitrogen gas into the containment vessel of reactor 1 to prevent a possible explosion of hydrogen that may be accumulating inside.