Meltdown Likely Under Way At Japan Nuclear Reactor

[jfchandler]

Japan Govt. Expands Advisory Against Eating/Shipping to 11 Vegetables from Fukushima Prefecture

Other Restrictions Issued for Products from Neighboring Ibaraki Prefecture

TOKYO, March 23, Kyodo News Prime Minister Naoto Kan instructed Fukushima Gov. Yuhei Sato on Wednesday to order residents not to eat leaf vegetables harvested in the prefecture for now after radioactive materials far exceeding legal limits were found in 11 types of vegetable grown in Fukushima, where a troubled nuclear plant is located.

Leaf vegetables subject to Kan's order included spinach, the ''komatsuna'' leaf vegetable, cabbage, broccoli and cauliflower, the government said.

Kan also instructed the governor to suspend for the time being shipments of these vegetables as well as turnips produced in the prefecture.

The Health, Labor and Welfare Ministry earlier in the day issued a call to consumers not to eat the 11 vegetables, including spinach and komatsuna.

The National Federation of Agricultural Cooperative Associations, or JA Zen-Noh, which distributes many of the prefecture's vegetables, has not shipped any of the produce since Monday, the ministry said.

In the latest sign that the impact of radiation leaks is slowly spreading beyond Fukushima, the premier also asked Masaru Hashimoto, governor of Ibaraki, a prefecture neighboring Fukushima, to suspend shipment of raw milk and parsley produced in his prefecture.

If a person eats 100 grams of the vegetable with the largest detected amount of radioactive materials for about 10 days, it would be equal to ingesting half the amount of radiation a person typically receives from the natural environment in a year, the ministry said.

If a person keeps eating the vegetable at the same pace, the amount of radiation intake could exceed the amount deemed safe, the ministry said.

The ministry detected 82,000 becquerels of radioactive cesium, 164 times the limit under the food sanitation law, in ''kukitachina'' leaves from Motomiya, along with 15,000 becquerels of radioactive iodine, which is more than seven times the limit, it said.

The ministry also detected a level of cesium drastically exceeding the limit in some of the other vegetables, it said.

Shipments of spinach from Fukushima have already been halted based on a special law for dealing with the nuclear disaster. In the latest test, the ministry detected radioactive materials from spinach produced in seven municipalities in the prefecture, including the city of Tamura.

The ministry decided to call on consumers to refrain from consuming those 11 vegetables after consulting with experts at the Nuclear Safety Commission of Japan, ministry officials said.

Also in Ibaraki Prefecture, radioactive materials beyond the limit were found in raw milk in Mito and Kawachi collected from Saturday through Monday, and in parsley harvested in Hokota and Namegata, it said.

The government on Monday ordered Fukushima to halt the shipment of spinach, ''kakina'' leaves and raw milk based on the special law.

The other Fukushima-produced vegetables subject to the government's instruction to refrain from consumption are turnips and similar green leaf vegetables -- ''shinobufuyuna,'' ''santona,'' ''chijirena,'' ''kosaitai'' and ''aburana'' rape.

http://english.kyodonews.jp/news/2011/03/80354.html

[powderpuff]

. It’s got a faulty reactor inside.”

I told you guys a long time ago that this design was condemned/onsoleted in 1972. GE knew this.

So congratulations on coming around weeks later. Sherlock.

[jfchandler]

Now here's another interesting science question:

According to the news this morning, not surprisingly, radioactive iodine and cesium are showing up in a lot of places around the Fukushima reactors, including in a wide variety of vegetables there and even in the soil. And even at lower levels in the tap water supply in metropolitan Tokyo.

Regarding sampling done 40 Km from the Fukushima plant, Gunma University Professor Keigo Endo says radiation released by the iodine is 430 times the level normally detected in soil in Japan and that released by the cesium is 47 times the norm.

Now, I'm not a scientist or an agriculturist, but here's the point. I've heard a lot of scientists interviewed on NHK saying the radioactive half-life of the iodine involved is relatively brief. But they've also been saying the radioactive half-life of cesium is far longer, something like 30 years.

If the vegetables harvested in the last week are showing radiation, that's probably due to particulate falling on them via rainfall or the air. And at some point the airborne emissions from the Fukushima plant presumably are going to stop.

But what about now the presence of highly radioactive cesium in the soil??? Once it gets in the soil, isn't is going to end up in all the vegetables grown in that soil -- and milk and meat etc etc -- for a very long time to come, given its half-life. If that scenario is correct, then that's a potentially very long term problem for the local food supply... That's my question...

[Jdietz]

You're absolutely right, Iodine levels are a short-term problem, Cesium a long-term.

But let's start with something that has been irritating me for a few days, the '14,000 times normal' etc claims. True as that may be, when dealing with very small (close to zero) numbers, they don't actually mean anything.

Let's take for example electricity, a microvolt is hardly detectable by instruments. You won't feel a thing probing with your tongue. 14,000 times that would be 14millivolt. You will still need a highly sensitive instrument to detect it, and as a human you have no way to differentiate it from the microvolt level.

Now starting at a Volt, you will maybe taste a little sour taste probing with your tongue, or the slightest of tingles. 14,000 times that will be 14kV, and you will basically disintegrate touching that with anything.

So these 'x times something tiny' mean absolutely squat, and is part of the normal scaremongering. What we need is the real numbers -and- the hard part, how much radiation is absorbed short and long term in the human body. This is hard, converting between Bq/Kg and mSv/year for spinach means you need to know what part just 'passes through' the body once, and what part is incorporated long-term.

It is unlikely that veggies will be grown again right outside the reactor site perimeter, but at current levels it is likely that a rainy season followed by a good plowing will be enough a bit further out. Iodine will be undetectable in a couple of months anyways.

I will need to defer the food -> dose conversion to biologists though, it's not just a 'divide by 100' problem.

Edit: one more tidbit: When Iodine (radioactive or not) is absorbed in the body, it concentrates in the thyroid, specifically endangering it. Cesium is distributed fairly uniformly throughout the body's soft tissues, so it doesn't form 'hotspots'

Edited March 23, 2011 by Jdietz

[flying]

This is a list of earthquakes in just the last week.........

http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/quakes_all.html

I gave up counting Japan quakes in just the last week after 160

[midas]

temperature in the No. 1 reactor vessel briefly topped 400 C degrees,[/b] requiring large amounts of seawater injected into the reactor to cool it down, according to the agency.

Some sources are not saying anything about " briefly topped " ?

How serious is this if stays at that level ?

[powderpuff]

Reactor design obsoleted in 1972

http://www.thaivisa.com/forum/topic/450765-meltdown-likely-under-way-at-japan-nuclear-reactor/page__view__findpost__p__4285424

[jfchandler]

NHK - Black smoke/steam spotted rising from Reactor No. 3... Workers in the area evacuated... May be similar to episode at reactor two days ago.

Edited March 23, 2011 by jfchandler

[jfchandler]

I believe I heard the reactor design standard for temperature is about 300 C degrees.. There was a mention on NHK this morning, I believe, that one of the reactor temperatures, not sure which one, had fallen to 360 degrees this morning.

A little overheating is a concern. A lot of overheating is a problem.

temperature in the No. 1 reactor vessel briefly topped 400 C degrees,[/b] requiring large amounts of seawater injected into the reactor to cool it down, according to the agency.

Some sources are not saying anything about " briefly topped " ?

How serious is this if stays at that level ?

[Jdietz]

temperature in the No. 1 reactor vessel briefly topped 400 C degrees,[/b] requiring large amounts of seawater injected into the reactor to cool it down, according to the agency.

Some sources are not saying anything about " briefly topped " ?

How serious is this if stays at that level ?

Not serious at all, as the pressure in the reactor vessel has been reduced to around atmospheric by venting. The design is for 300C -under pressure- while operating. Steel won't melt until much much higher, not even soften at 400C

[jfchandler]

NHK

Govt. to gauge radiation 30 km off Fukushima coast

Japan's science ministry says it will expand the scope of its radiation monitoring in waters around the quake-hit Fukushima Daiichi nuclear power plant to 30 kilometers offshore.

The ministry said it will start the monitoring on Wednesday, after detecting radiation above legal limits in the ocean around the plant.

A survey ship is to collect seawater at 8 locations at 10-kilometer intervals over a distance of 70 kilometers.

The ministry plans to release its findings after comparing the new readings with old data collected yearly in the same areas.

Experts say rainwater and water sprayed on reactor buildings of the plant to cool their spent fuel storage pools could be flowing into the ocean.

The Tokyo Electric Power Company, which operates the plant, said the amount of radioactive iodine-131 found 330 meters south of the plant's water outlet was 127 times the legal limit. The amount 16 kilometers south of the plant was 16 times the limit.

Wednesday, March 23, 2011 10:34 +0900 (JST)

http://www3.nhk.or.jp/daily/english/23_17.html

[jfchandler]

NHK:

Cities Continue to Record Above Normal Radiation Figures

Radiation levels in many areas of eastern and northern Japan continue to be higher than normal.

Municipalities and other institutions are measuring their radiation levels.

According to measurements taken by 9 AM Wednesday, 6.09 microsieverts per hour were observed in the city of Fukushima, 65 kilometers northwest of the quake-damaged Fukushima Daiichi power plant.

In the town of Onagawa, about 160 kilometers northeast of the plant, the figure was 1.3 microsieverts.

In Kitaibaraki City, located south of the Fukushima plant, the radiation level was 1.45 microsieverts.

In Mito City, further south, the figure was 0.33 microsieverts.

Radiation levels were also higher than usual in other cities, including the prefectural capitals of Yamagata, Tochigi, Gunma, Saitama, and Tokyo.

Health authorities say one hour of exposure to the radiation at Fukushima city, which showed the highest reading, would equal one-100th of the amount of radiation received in a single stomach X-ray.

Wednesday, March 23, 2011 12:58 +0900 (JST)

http://www3.nhk.or.j...lish/23_22.html

Edited March 23, 2011 by jfchandler

[jfchandler]

So these 'x times something tiny' mean absolutely squat, and is part of the normal scaremongering. What we need is the real numbers -and- the hard part, how much radiation is absorbed short and long term in the human body. This is hard, converting between Bq/Kg and mSv/year for spinach means you need to know what part just 'passes through' the body once, and what part is incorporated long-term.

It is unlikely that veggies will be grown again right outside the reactor site perimeter, but at current levels it is likely that a rainy season followed by a good plowing will be enough a bit further out. Iodine will be undetectable in a couple of months anyways.

Jd, here's the actual information from the government earlier today, and it's hardly, as you put it, right around the plant's perimeter... The sampling they did was 40 Km away...

Japan's science ministry says radiation exceeding 400 times the normal level was detected in soil about 40 kilometers from the troubled Fukushima Daiichi nuclear power plant.

The ministry surveyed radioactive substances in soil about 5 centimeters below the surface at roadsides on Monday.

The ministry found 43,000 becquerels of radioactive iodine-131 per kilogram of soil, and 4,700 becquerels of radioactive cesium-137 per kilogram about 40 kilometers west-northwest of the plant.

Gunma University Professor Keigo Endo says radiation released by the iodine is 430 times the level normally detected in soil in Japan and that released by the cesium is 47 times the norm.

While acknowledging that Japan's current radiation exposure standards, by various accounts, are quite conservative, those levels of cesium 40 Km from the plant don't sound like "squat."

[jfchandler]

NHK - Govt. releases estimate Wednesday saying damage expenses from the major earthquake and tsunami, including the Fukushima reactors crisis, could top $300 billion -- exceeding estimate earlier this week from the World Bank.

[elcent]

NHK - Govt. releases estimate Wednesday saying damage expenses from the major earthquake and tsunami, including the Fukushima reactors crisis, could top $300 billion -- exceeding estimate earlier this week from the World Bank.

Switzerland estimated it at 700 - 800 billion $$$ over a week ago.

[Jdietz]

47 times nothing is still nothing. If there's a biologist in the room I would love to get an opinion on how:

4,700 Bq/kg Cs-137 in soil translates into crop radiation level, and subsequently what added yearly dosage an average human can expect when eating these crops.

Here's a couple of quotes so far I hope to get things back in perspective. Though like I said, I would love to be educated by a nuclear biologist, if you're here, please raise your hand!

Levels of caesium-137 detected in spinach in Japan over the weekend stood at an average of 350 becquerels per kilogram, well below the European Union's limit of 1,000 becquerels for dairy produce and 1,250 for all other food items.

"Becquerels are like atoms," said Pradip Deb, senior lecturer in Medical Radiations at the School of Medical Sciences, Royal Melbourne Institute of Technology University.

"A litre of milk has billions and billions of atoms … and this is just 350."

One more thing about the radioactive Iodine, if you can store the produce for 80 days, it'll be gone. (10 half-life periods)

Edited March 23, 2011 by Jdietz

[jfchandler]

NHK video shows a special Japanese construction crane, normally used to pour concrete for high-rises, is using its 50 meter long arm to pour seawater into the spent fuel rods cooling pool at Fukushima Daiichi Reactor No. 4 on Tuesday.

[jfchandler]

Me too, Jd... That's why I posed the question...

But the other thing to consider is...the future there likely isn't going to involve exposure from a single food or drink or source, but from a multitude of various sources that will be collectively additive, although they may also have different uptake levels.

Interestingly, one of the reasons Cabinet Secretary Edano gave earlier today for why the govt. is imposing the various restrictions now, even though the levels right now generally aren't imminently hazardous, is that the levels "are likely to continue for a long time."

47 times nothing is still nothing. If there's a biologist in the room I would love to get an opinion on how:

4,700 Bq/kg Cs-137 in soil translates into crop radiation level, and subsequently what added yearly dosage an average human can expect when eating these crops.

Edited March 23, 2011 by jfchandler

[elcent]

and like this ...

[slapout]

Radiation dosage/exposure was explained to me, in the workplace, exposure to human is cumulative, while fallout onto the plants and thus soil is contamination. I 131 has a short half life whereas CS 137 does not.

Both types mentioned are used in operations in various business worldwide.

I am not familiar with terms being used for measurement in today's world but the fallout of CS 137 and subsequent contamination of the surrounding area would require massive cleanup in the real world.

The very few times I have heard of CS 137 rupture and contamination, the local was relative small (1 or 2 acres) but the clean up cost was huge. Even structures are affected, although there are practical ways to sanitize them the soil/edible plants, livestock, etc are a different matter.

[Jdietz]

Here is a reference about the Cs-137 contamination in Germany after the Chernobyl disaster. Note that emissions of that disaster where orders of magnitude greater than the 'controlled' venting currently going on.

http://www.environme...s_E1/cs_e1.html

During the months directly after the Chernobyl fallout food sources growing or raised outside as well as meat from herbivorous wild animals was contaminated at a higher rate with radiocesium. While the radiocesium contamination in agriculturally produced plant and animal foods has declined since the last few years to pre-Tschernobyl levels, comparatively high levels of Cs-137 can still be found in berries, mushrooms and the meat of game animals from certain forested areas.

These differences in Cs-137 contamination are caused by the fact that the transfer of radiocesium from Cs ion fixing clay minerals in the soil to the crops growing there is low and the high nutrient content, and the high pH-value of agriculturally used soils also inhibit transfer. In contrast this transfer to plants in forests, esp. on forest soils with thick humus layers is relatively high. In addition dynamic biological processes (deposition of litter, decomposition, etc.) occur in forest ecosystems along with purely physical processes (adsorption, fixation,etc.), both of which have a complex influence on the vegetation and wild animals.

We have been investigating the long term behaviour of radiocesium in undisturbed ecosystems with emphasis on "forest products" since 1986.

Edited March 23, 2011 by Jdietz

[Jdietz]

NHK World: Black smoke seen at the #3 reactor seems to be fading.

"The smoke is dwindling but it is not gone yet"

"Radiation level at the measuring point hasn't changed"

Edited March 23, 2011 by Jdietz

[jfchandler]

That's an interesting document, Jd, and very pertinent to the question I posed earlier... talking about how the cesium from Chernobyl was generally spread and deposited over Europe, and Germany in particular, via rainfall...

As regards to cesium 137, it seems to be saying the uptake levels aren't high in agricultural production settings... though they don't say how much or little not high.

I can't quite tell what that web site is, or who/what is the source of that article.

[Jdietz]

It seems to be a private German company, specialized in Radioactive Cesium research. I have no idea about their political leaning.

http://www.environme...logy/Rad-E.html

Radioecology: Protection & Surveillance & of the Environment and Research

Environmental Studies is engaged in radioecology research on soil, plants, game and complete ecosystems since 21 years. We are specialists on the behaviour of radiocesium.

Also from the studies:

This research was conducted with funds of the Federal Ministery for Environment. Nature Protection, and Reactor Safety.

This report reflects the views and opinions of the contractor and need not necessarily correspond to those of the sponsor

Edited March 23, 2011 by Jdietz

[jfchandler]

Add on this... Seems like we're talking in general about multiple years in length...

Pterydium aquilinum has the longest effective halflife of Cs-137, 23.8 years. For the other plants the values range between 2.9 and 8.4 years. The half-lifes of the individual plant species correspond relatively well for the 3 sample plots. Raspberry always has the shortest effective halflive with an average value of 3.6 years. The leaves of Athyrium filix femina and Vaccinium myrtillus always have longer halflives, on average 7.2 and 7.0 years respectively.

The effective half-lifes were calculated for the time period 1989 to 2000. However, Cs-137 activity did not decrease uniformly in the plants. For all species investigated except P. aquilinum the rate of activity reduction was relatively quick from 1989 to about 1994. During a distinct slowdown in reduction (for ex.blackberry and raspberry on F1, D.carthusiana on B1 and B2), no change (for ex. V. myrtillus on B1 and B2 and L. sylvatica on B2), or an increase of Cs-137 activity (for ex. P. aquilinum on F1 and raspberry on B1). Due to the brevity of the investigation period and the small changes in Cs-137 activity these trends are statistically not significant.

This research was conducted with funds of the [German] Federal Ministery for Environment. Nature Protection, and Reactor Safety.

http://www.environme...s_E4/cs_e4.html

Edited March 23, 2011 by jfchandler

[Jdietz]

I was just reading the same studies, the good news is that in most plants, the effective half-life is a lot shorter than the specific half-life of the Cesium-137 involved (due to earth-binding and absorption)

Edit: Note that we are talking specifically about Cs-137, the other compounds (especially I-131) will be mostly gone in a month or two and undetectable in 3 months.

Also: the full editor is borked.. superscript not working at all..

Edited March 23, 2011 by Jdietz

[jfchandler]

Right, that's why I've only been talking about cesium as a longer-term concern... Because the presence of the iodine is short-lived...

You know Japan is quite big on mushroom production, including some very fancy and expensive gourmet varieties, like Matsutaka mushroom...

Seems like mushrooms and berries are likely to be a problem, if the German/Chernobyl experience is any example.

[jfchandler]

The Japanese govt. now has a newly revised English language web page with links to the various radiation monitoring reports gathered together... prefecture reports, 20 Km reports, and drinking water reports...

http://www.mext.go.jp/english/radioactivity_level/detail/1303962.htm

[jfchandler]

My favorite post of each day...the daily 20 Km radiation monitoring reports for areas 20 to 30+ kilometers away from the Fukushima Daiichi plant.

Peak levels appear to be down from the day before... High reading is 95 microsievert per hour at monitoring location #33, followed by 75 uSv per hour at location #32... No readings above 100 uSv, unlike the past few days.

[elcent]

Are there any magic tricks that we don't get iodine-129 readings? http://www.epa.gov/r...ml#affecthealth

Where do iodine-129 and iodine-131 come from?

Both iodine-129 and iodine-131 are produced by the fission of uranium atoms during operation of nuclear reactors and by plutonium (or uranium) in the detonation of nuclear weapons.

Top of page

What are the properties of iodine-129 and iodine-131?

Radioactive iodines have the same physical properties as stable iodine. However, radioactive iodines decay with time

Iodine is a nonmetallic, purplish-black crystalline solid. It has the unusual property of 'sublimation,' which means that it can go directly from a solid to a gas, without first becoming liquid. It sublimes to a deep violet vapor at room temperature. This vapor is irritating to the eyes, nose and throat. Iodine dissolves in alcohol and in water. It melts at 236 °F.

Iodine reacts easily with other chemicals, and isotopes of iodine are found as compounds rather than as a pure elemental nuclide. Thus, iodine-129 and -131 found in nuclear facilities and waste treatment plants quickly form compounds with the mixture of chemicals present. However, iodine released to the environment from nuclear power plants is usually a gas.

Iodine-129 has a half-life of 15.7 million years; iodine-131 has a half-life of about 8 days. Both emit beta particles upon radioactive decay.

A great site to visit for further info on health impacts

Edited March 23, 2011 by elcent