Nuclear Open Thread

Fukushima Open Thread 2

The last Open Thread dedicated to the Fukushima Daiichi crisis is getting overloaded, so here is a new one. Same rules apply:

The Open Threads on are a general discussion forum, where you can talk about whatever you like — there is nothing really ‘off topic’ here — within reason. Please use this particularly comment thread to post anything on the Fukushima Nuclear Accident that is NOT directly related to the content/intent of the other threads (which are usually about status updates, engineering details, specific perspectives, etc.).

The sort of things that belong on this thread include general enquiries, soapbox philosophy, meandering trains of argument that move dynamically from one point of contention to another, and so on — as long as the comments adhere to the general topic of nuclear energy, climate change mitigation, energy security, and the Fukushima crisis.

Please follow the commenting rules, although the ‘stay on topic’ rule obviously does not apply as strictly here.

Finally, a suggestion. There are often multiple trains of discussion going on, and a comment stream is not really the best way to manage this (a PHP forum would be preferable for this purpose — but we make do with what we have — this blog/website is not primarily intended as an undirected/unmoderated usenet-style listing). In lieu of this, I recommend that you preface your comment with a bold category word, so people can quickly ascertain what you are talking about, e.g. <b>radiation health physics</b> or <b>nuclear insurance</b> or whatever.

By Barry Brook

Barry Brook is an ARC Laureate Fellow and Chair of Environmental Sustainability at the University of Tasmania. He researches global change, ecology and energy.

236 replies on “Fukushima Open Thread 2”

re Tsunami Height

As I understand it, you cannot judge the risk of a certain height tsunami along a coast based on the height a historical tsunami was at another adjacent beach or area of the shoreline.

The height a tsunami winds up being, or how far it comes ashore, is highly dependent on the conformation of the ocean floor leading up to the shoreline. So it apparently can easily be the case that one area of the shoreline historically gets 20 ft. tsunami’s every X number of years – while a short distance down the coast it may be literally impossible to get a wave of even half that size.

In other words, it is apparently like most things in this world – not as simple as one might wish, and not as easy to pin blame on folks if a monster hits, unless you know for certain that the particular area of coastline really is prone to those.

So if, for example, the US coastline has periodically seen 20 ft tsunamis, well, it may be that siting a nuclear plant at the specific locations that have actually gotten waves that big in periodically really would be bad… but it could also be that plenty of locations are situated such that they NEVER get even 10 ft tsunamis… So should plants sited there be required to be prepared for 25 or 30 ft tsunami’s, as you’d have to for the locations that get 20 footers?

I would say no – it would be a huge waste of money and resources that could be better spent elsewhere, rather than using rate payer (tax dollars, out of your pocket), beefing up for something that as best we can tell isn’t possible at that location.


A metor impact into the ocean could create a tsunami anywhere. Some NPP called submarines are already tusnami proof.


Thanks for your thoughts. Anyone else on the subject? Is there anyone working in the industry who knows how risk assessments work?


re Tsunami Height
@Rational Debate
I had the same question regarding local tsunami behaviour. Given 33 m was experienced at Sanriku, what were the characteristics of the energy initiating the tusanmi (location, volume displacement, …) and what was the height at Daiichi? I will put that question to prof. Bilham via Roger Pielke.


re Tsunami Height

Risk assessment according to French engineers is based on historical records. Take the worst known event in the past 1000 years and add some margin.

Dreaming about very unlikely natural events such as “A meteor impact into the ocean could create a tsunami anywhere.” is interesting if you are a Hollywood movie writer. Pointless for design guidance.

Of course, human-generated events are a different matter (negligence, deliberate attacks, terrorism…)


Thanks Francois. Good to know how it is done in France. Is there any international regulation on this or is it up to each individual state (or even up to the commercial companies)? Any British experts?


re Tsunami Height

The IAEA is publishing a lot of safety standards. Not sure if they cover tsunamis and the likes.


LNT query

Is there any scientific body that has rejected the LNT theory? I don’t have the knowledge to asses this on my own, so I’d like to know if there’s any scientific review (peer reviewed or from a scientific body) suggesting that the LNT is wrong. Thanks.

I take the chance to thank everybody here, from Barry Brook for this blog and the detailed and rigourous coverage of the Fukushima event to all commenters for your instructive feedack and updates (I hadn’t even heard of the LNT before!). Thanks.


radiation and LNT
@DV82XL: Thanks for a great analogy. If I had the opportunity to exploit your counter-LNT approach tomorrow I would omit the last bit “we could confidently assert that jumping rope should be banned on all school playgrounds since statistically anyone making 100 one-foot jumps would die.”
I think your example is a bionomial distribution, where for the case of surviving 100 trials of rope skipping with 99% probability of survival on each trial I get a mean of the distribution = 36.7% survive, 63.4% die.


Question for Barry if I may. If I understand you correctly, you do see a broad scientific consensus on climate change. But what is the current status of scientific research into the effects of man-made radiation? From what I can glean, studies of the same event, e.g. Chernobyl, come up with health effects that are orders of magnitude apart. Is scientific consensus in this area still lacking and, if so, why?


Cup, in short, the problem is chronic lack of good data at low radiation doses — and the difficultly of measuring tiny effects which require enormous sample sizes. There have been some excellent reviews in the primary literature on this problem, however, and I’ll see if I can dig one up. In general they tend to support a threshold — or indeed hormesis — much more than a no-threshold model, but in the absence of really strong information, the ‘null’ model (the LNT) has, historically, been ‘preferred’.

More details on this BNC post: Radiation – facts, fallacies and phobias

…and this excellent review paper by Prof David Wigg:


Atlantic and Tsunami disaster preparedness

@Eric Moore, on 28 March 2011 at 9:04 PM said:

So could someone enlighten me on the measures taken on the East coast of USA and the UK plants regarding Tsunamis.

In the US, the USGS identifies Tsunami risk zones.
On the Pacific coast, Tsunami risk zones have Tsunami evacuation route signs.

On the Atlantic coast the Hurricane Storm surge from Katrina was as high as 28 feet. Since the storm surges from relatively frequent hurricanes are higher then the the highest recorded Tsunami on the US Atlantic coast one plans for the more common and more devastating Hurricane Storm surges,


Thanks Harrywr2

Still would quite like to know about the UK in terms of Tsunami risk and nuclear power. Any UK risk experts?


There are many anti-radiation who claim that since it is possible for a single gamma ray to damage a single cell which in turns mutates into a cancer cell, any radiation is bad.

Is this LNT or something else? The people who use the argument i stated rarely ever cite % or odds. They just say that since it is possible any increase increases are harmful.

Technically their argument seems plausible, but without the numbers it is out of context and only useful for FUD not real preventative action.


radiation and LNT

“for the case of surviving 100 trials of rope skipping with 99% probability of survival on each trial I get a mean of the distribution = 36.7% survive, 63.4% die.”

Exactly right, Steve. DV82XL fell into a common probability trap ;-) Try to explain that to the average public…

Now let’s forget about theory. People are scared about radiation, and we all have to live with this fact. Take cellphones for example: people are scared of radiation from base stations, but they are willing to carry a cellphone which is using exactly the same transmission power.

Fears (and inconsistency) are a fact of human psychology. Maybe educating the masses will help in the long term, but that is a long and difficult path.


Anybody following this story with any interest may recall the explosion of the supression pool to unit No. 3 (the one that used MOX fuel). I think most of us realized that this was a reactor breach, although I don’t think I have heard anybody actually confirm that. I don’t believe there can now be any doubt: Plutonium detected in soil at Fukushima nuke plant (Kyoto reports):

From a TIME magazine blog back when MOX was being explained:
there are four kinds of carcinogenic isotopes released when a nuke plant blows: iodine-131, cesium-137, strontium-90 and plutonium-239. Plutonium is not only the most lethal of the four (“extraordinarily toxic” is how Dr. Ira Helfand, a board member for Physicians for Social Responsibility, describes it), it also hangs around the longest. It’s half life is a whopping 24,000 years, and since radioactive contamination is dangerous for 10 to 20 times the length of the isotope’s, that means plutonium emitted in Fukushima today will still be around in close to half a million years.



Ms Perps, no one with any scientific training would countenance 99% of Caldicott’s stated opinion, yet I fail to see why you focus on dismissing statisticians and the role of statistical analysis in scientific inquiry.
In Professor Brooks own words:

“Topics: My research methods focus primarily on the statistical analysis, interpretation and computational modelling of complex systems, long-term data, and meta-analysis of large-scale databases. Scenarios for future impacts are
modelled at global, regional and local scales, to provide a robust scientific underpinning for scientific management and government policy.

The link is:


Thank you for the response and link:

“I’ll have to do a post about Pu at some point soon. It’s a metal guys, not a demon.”

That quote certainly helps to clarify how to evaluate information provided on this site. A bullet is just metal also. Whether it is on the shelf or just left the barrel of a gun pointed at someone’s body changes the seriousness with which the material should be rationally viewed.

I look forward to your post on Pu, at some point.


@ Darren Addy:

But what is the actual concentration of plutonium detected? We’re not told. It’s possible to detect these things at remarkably dilute concentrations.

It could be from nuclear weapons fallout, or even naturally occurring extremely rare plutonium-244. But we’re just not told any real information here, which is typical of the no-details scientifically illiterate media reporting we usually see.

Even if plutonium was released from a reactor’s fuel, it could be from any one of the reactors, even without MOX fuel. All uranium-fueled reactors form some plutonium nuclides within their fuel.

All domestic tap water typically contains measurable Pu at a concentration of something like 0.1 fCi/L – yes, that’s f as in femto as in 0.1 * 10^-15 Ci/L. And that concentration is quantitatively measurable. The maximum acceptable threshold for municipal drinking water is something like 5000 fCi/L.

By the way, plutonium is not as dangerous as some people imply that it is.


Luke Weston, on 29 March 2011 at 5:21 AM said:

@ Darren Addy:

But what is the actual concentration of plutonium detected? We’re not told. It’s possible to detect these things at remarkably dilute concentrations.

It could be from nuclear weapons fallout, or even naturally occurring extremely rare plutonium-244. But we’re just not told any real information here, which is typical of the no-details scientifically illiterate media reporting we usually see.

Even if plutonium was released from a reactor’s fuel, it could be from any one of the reactors, even without MOX fuel. All uranium-fueled reactors form some plutonium nuclides within their fuel.

All domestic tap water typically contains measurable Pu at a concentration of something like 0.1 fCi/L – yes, that’s f as in femto as in 0.1 * 10^-15 Ci/L. And that concentration is quantitatively measurable. The maximum acceptable threshold for municipal drinking water is something like 5000 fCi/L.

By the way, plutonium is not as dangerous as some people imply that it is.


The media is not to blame – Tepco and the authorities are the ones who are not giving detailed data to the press to report. In fact, I think the press has shown remarkable restraint. If this crisis was a political issue they would have an endless parade of “experts” giving their take on the situation.


In the wake of Japan’s nuclear crisis at the Fukushima Dai-ichi Generating Station (FDI), the credit-rating company Moody’s announced today that it was reviewing long-term ratings for eight Japanese electrical utilities for possible downgrades.

“Moody’s believes that this nuclear crisis could impact the electric utility sector significantly and result in a fundamental reassessment of the use of nuclear power in Japan, perhaps resulting in earlier than anticipated decommissioning of some nuclear plants and the potential cancellation or indefinite postponement of some new nuclear generation. These developments are likely to result in accelerated decommissioning costs, increased capital expenditures for higher cost replacement generation, lower reserve margins, and higher operating costs at existing nuclear plants as a result of increased scrutiny, more stringent safety procedures, and longer required maintenance outages.”


@Frank Kandrnal
You must be a very fast reader. I’m impressed. I’ll be warned to not waste any carefull formulations on your comment in the future. Just short clear text like:

“You must have missed it. Retorical tricks do not support an argument. They merely undermine the dialog.”


… plutonium is not as dangerous as some people imply that it is

Would that they would merely imply … for their sakes.

As I said in a Guardian comment thread March 25,

The Japanese government is certainly monitoring plutonium, and so are independent entities doing nuclear weapon test ban enforcement.

Every life the Japanese nuclear sector has saved has cost the Japanese government hundreds of millions of dollars in lost natural gas revenue, so if any plutonium from Fukushima had been detected, you would certainly have heard.

Plutonium is a good deal less “toxic” than radium. To make a watch dial light up, radium emits alpha rays; this is the source of its so-called toxicity. Plutonium emits a lot less of them, and here, too, the harm it can do, if inhaled or ingested, is entirely due to alpha rays.

If going to the beach without sunblock, beware of sun poisoning.

… without the above version’s emphasis.

Since then we have heard of plutonium at Fukushima, but not in amounts out of line for deposition from nuclear testing. Plutonium-243 has a half-life of 4.956 hours, so after … how long has it been? 17 days, 408 hours? So if any of that came from the reactors, it will be down exp-57-fold from the equilibrium that existed the moment before they shut down. No possibility of detection there.

There would also have been an (even smaller) equilibrium level of plutonium-245, and its longer half-life, 10.5 hours, means it’s down only 500 billion-fold. Still not useful.

If you are the Canadian province — that is the correct spelling, by the way, not “provence” — of Ontario, the Darlington public hearings are continuing this week and the next. I went, as above said, and accentuated the positive, but very briefly.

You may well be able to do better; you may be one of those extroverted technical people who looks at his listener’s shoes rather than his own. Go.


> we’re just not told any real information here

True problem.

Try over here instead:
Press Release (Mar 28,2011)
Detection of radioactive material in the soil in Fukushima Daiichi Nuclear Power Station

On March 28th 2011 … analysis of plutonium contained in the soil collected on March 21st and 22nd at the 5 spots in Fukushima Daiichi
Nuclear Power Station. As a result, plutonium 238, 239 and 240 were detected as shown in the attachment….

‹Results of the analysis›
-Plutonium was detected in the soil …
-The detected plutonium from two samples out of five may be the direct result of the recent incident, considering their activity ratio of the plutonium isotopes.


The first 2 attachment PDFs at that press release are site maps with locations identifying soil samples taken.
The third one is results. Sounds like they’re comparing what they found to what was found after some particular nuclear test — I’d GUESS the Chinese atmospheric tests?

Brief excerpt — click the links to the TEPCO press release above to get the full texts. Again, this is from their press release of March 28th

“Result of Pu measurement in the soil in Fukushima Daiichi Nuclear Power Plant
1.Result of the measurement
… Activity ratio of Pu-238 detected in site field and solid waste storage against Pu-239 and Pu-240 are 2.0 and 0.94 respectively. They exceed activity ratio of 0.026 which resulted from the atmospheric nuclear test in the past, thus those Pus are considered to come from the recent incident.”

Long-term trends of plutonium fallout observed in Japan — 4 June 2007.


A comprehensive data set of plutonium deposition samples collected monthly (partly quarterly), from 1957 to 1997, by the Meteorological Research Institute (Tokyo until March 1980 and Tsukuba since April 1980), Japan is reported, together with information on the geochemical and meteorological factors controlling the plutonium fallout. The maximum fallout rate of 239,240Pu during the sampling period was observed in June 1963, after the 1961–1962 period of US/former USSR atmospheric nuclear weapons testing. Annual 239,240Pu deposition decreased in the period from 1963 to 1967 according to the stratospheric residence time of nuclear debris. From 1968 to 1984, the level of 239,240Pu deposition was mainly controlled by stratospheric fallout from atmospheric nuclear weapons testing in China. After 1985, the 239,240Pu fallout showed no decrease, which may be attributed to resuspension of deposited plutonium. In May 1986, the Chemobyl radioactivity was observed in rain and air samples in Japan. The Chemobyl-defived Pu isotopes, which are characterized by higher 238Pu/239,240Pu and 241Pu/238Pu activity ratios than those of the nuclear-test-derived 239,240Pu , were detected in deposition samples in Japan. However, the level of Chemobyl 239,240Pu in Japan was very low compared to that in Europe.”


Quotes “Richard Lahey, who was General Electric’s head of safety research for boiling water reactors when the company installed them at Fukushima.”

the article continues:

“The latest setback engineers face is the discovery of highly radioactive water in and around the turbine building at reactor two. Radiation detectors measured the level at 1,000 millisieverts per hour and as workers are allowed an exposure of 250 millisieverts a year, raised from 100 millisieverts before the crisis, they could only be in the contaminated area for 15 minutes before reaching the maximum dose.

Engineers cannot resume work on connecting the power to reactor two until they have drained the water pools and scrubbed the area clean, an effort now underway.

Officials at Tepco, who run the plant, say it is not clear where the radioactive water came from, but it escaped from the reactor core, either directly through a breach in the containment vessel or through a crack or hole in pipework.

Lahey believes that molten fuel inside reactor two has begun to leak out of its containment vessel, meaning it may be too late to save that reactor.

… “They are doing all the right things now, but this is a tight horse race,” Lahey said.”


Why has TEPCO waited until now to figure out what they will do with the radioactive water at the plant? Could they not have been constructing lined holding reservoirs or bringing in large casks or lead-lined tanks? IMHO they are inept in developing contingency plans AHEAD OF TIME.


Kudos to DV8 for challenging the LNT theory. This is clearly an issue that could use some unbiased research but most of the researchers start with their blinkers on, allowing them to see only the harmful effects of radiation.

Here is a presentation by Y.C. Luan showing there are positive as well as negative effects following exposure to ionizing radiation:

Luan invites other researchers to examine his findings with an open mind but it is hard to get research dollars for research that might support such an unfashionable idea.


Plutonium origins

Plutonium-238 irradiated with fission neutrons has a 3.669-millibarn cross section for absorbing one and then losing two.

This of course yields the isotope plutonium-237, which has the sort of half-life we’re looking for: 45.2 days. Source of plutonium other than Fukushima cores are many times longer ago than that, but those cores’ shutdown is much less time ago, so it could only come from them.

And their run times were several times 45 days, so when the earthquake hit, it would have been very near equilibrium, i.e. decaying at almost exactly the rate the (n, 2n) reaction was producing it.

(How fire can be domesticated)


Steve Darden wrote:

radiation and LNT
@DV82XL: Thanks for a great analogy. If I had the opportunity to exploit your counter-LNT approach tomorrow I would omit the last bit “we could confidently assert that jumping rope should be banned on all school playgrounds since statistically anyone making 100 one-foot jumps would die.”
I think your example is a bionomial distribution, where for the case of surviving 100 trials of rope skipping with 99% probability of survival on each trial I get a mean of the distribution = 36.7% survive, 63.4% die.

The health risk from radiation is not about probabilities, it’s about the response of our immune system. We live on a radioactive rock. We have biological defenses against normal background radiation. Elevated levels causes damage to our cells (and regulatory functions) and can lead to stress conditions that give rise to hormetic effects (boosted immune system response). Above these levels, the body’s immune system can’t keep up, and you get what is the nuclear energy equivalent of a runaway chain reaction (or criticality event within your core) … aka cancer. Damage from different radiogenic isotopes seek out different biological structures in the body: lymph system, bone, muscle, etc. So different structures of the body are impacted by radiation in different ways (age and a compromised immune system also plays a role).

I think the jumping rope analogy (and LNT hypothesis) captures this fact pretty well. Jump rope for 20 minutes, you’ll get a good workout. Stress to your body makes your bones stronger, muscles grow, circulates blood to vital areas providing an overall “healthful function.” Jump rope for 40 minutes, you are experiencing higher levels of stress, and your bones, body, respiration (and ability to recover quickly from the exercise) may be compromised. Jump rope for an hour with a risk factor of some sort or another, and you may develop a pain in your chest, get a headache, or pass out from exhaustion. Jump rope for a longer period and you may die. 5% of people in 50-65 year age rage may die after 90 minutes of skipping rope, 15% of people in same age range after two hours, and so on.

We can try and simplify the LNT risk assessment model so it makes almost no sense whatsoever. This is called a “straw man argument.” Most knowledgeable people don’t do this, and make some room for a precautionary outlook based on a detailed knowledge of human physiology, risk factors, dose rates and time of exposure, isotopic type, medium, and concentration, and a great deal more …

I find much of this discussion misleading … since radiation (of any kind and level) is not supposed to leave the power plant in the first place. If someone spits in your food at a restaurant, nobody asks “does that person have a cold” before they decide to react. The are repulsed by it regardless of the condition or amount of the spittle contained in your food.


The crisis at Fukushima should not be minimized. But on the subject of radiation here is an article published by the BBC a couple of days ago by Wade Allison.

Viewpoint: We should stop running away from radiation
By Wade Allison
University of Oxford
(Wade Allison is a nuclear and medical physicist at the University of Oxford, the author of Radiation and Reason (2009) and Fundamental Physics for Probing and Imaging (2006).)


The relevance of LNT to the events in Japan, and the broader question of nuclear energy has nothing to do with containment. It is a given that every effort should be made to keep radiation and radioactive material out of the environment. Where it does have an impact is on how the aftermath of an incident like this one is handled by the press and the authorities.

There as been too much of a radiophobic reaction by both to very small increases in the background. Hysteria about detecting particles from this event in Europe and North America and the reaction in Japan to minor increases in radioisotopes in foodstuffs plays to public perceptions of danger that official acceptance of LNT have generated. That is the problem: panic without cause.


> A radiological incident in Taiwan revealed
> chronic radiation is always beneficial to humans-2

Maybe. Citing the actual paper will get you a rather different summary than citing that PowerPoint show, which makes claims beyond what’s been published in the journal. Stay with the journal, is better.

Try here:

But that’s about gamma — and look at the citing papers, the effect claimed is explicitly _not_ about alpha radiation, and we know beta’s not good either.

And those are published in a journal that is a dedicated single-subject journal for the idea.

If there’s an effect, it’s relatively smaller than the forcings so much disputed in the climate change area and any health effect is going to be very hard to pull out statistically. It’s interesting, not convincing. I don’t see anyone publishing a convincing study showing any health effect either good or bad at the low levels of natural variation.

Heck, when I was in grade school in the 1950s, I took bundles of household beans up to the local nuclear lab (an electron-beam facility, a beta source) and got the staff there to irradiate them for me, and sho’ nuff, the low-dose beans sprouted better and grew faster than the controls, while the middle and high-dose beans looked poorly and devastated respectively.

But I hadn’t discovered hormesis. I”d discovered what was quite familiar, that irradiation reduces the levels of bacteria and fungi on the outside of the seeds. Using radiation to preserve food from decay is pretty well understood by now.

Question: what do people who believe a little more radiation will improve their health do to get that additional exposure?

Would you expect to be able to show an effect?

“Norway’s permissible radiation level in meat is five times that of the European Union.
Since the Chernobyl disaster in 1986 publication of radiation levels in livestock has been an annual ritual in Norway….”

Eat more reindeer? It’s available. Or more whale meat, probably, though I don’t know that that’s been tested.

The issues are mostly concern about bioaccumulation of types of radiation sources not found in nature.


Water flows to the lowest point accessible. We’ve seen day after day of helicopter drops and water spraying from trucks onto the reactor buildings and SFP. Why is it a surprise that a besement of a nearby building would be filled with radioactive water.

The presence of radioactive water does not necessarily mean it came from a RPV or primary containment.

IMHO, ther has been way too much jumping to conclusions based on fragments of facts.


MODERATOR: Sorry, the above post came out a bit garbled. Please delete if you want.

Cl-38 in leaked reactor water.

William Fairholm, on 27 March 2011 at 1:51 AM said:

In thread 10+ days of crisis at the Fukushima Daiichi nuclear power plant – 22 March 2010

The more I think about it the crazier it seems. The neutron
cross-section of Cl-37 is 430 millibarns, which isn’t small, but isn’t large

You’re right, the cross-section is not especially large, and if the Cl-38 were
produced by neutron activation of the salt in the seawater by some ongoing
fission in the reactor, I don’t see how it can be there without also seeing
Na-24, with half-life of 11 hrs, and many other activities from other
impurities in the seawater, too.

I tried to think of some route, to get Cl-38 alone, or possible excited Ar-38.
But I can’t come up with anything plausible with single neutrons at thermal
fission energies: eg the (n,3n) reaction on Ar-40, which is about 1% in air
and seawater at sea level, has a cross-section in the microbarn range. You’ld
need 3 GeV protons on U or Pb to get even a few millibarn cross-section for
producing Cl-38 directly. And those kinds of energies are out of the question,
they could only be from cosmic rays, and the flux is essentially zero.

I did have a thought, though. I imagine that it’s possible to get some buildup
of Cl-38 in a BWR during normal operation if there’s any influx of Cl-37 from
salt somehow dissolving into the coolant water, coming from anywhere in the
system, since there’s a high thermal neutron flux when the reactor is at full
power? And if that’s the case then it must be necessary to clean the Cl-38
out continuously, or else the coolant will become very radioactive, which
would be very undesirable.

So if that’s true, then there must be a system to clean out the Cl and Na, and
I’ld suppose that that cleanup system is not operating right now, or at least
that it wasn’t working for many days.

Now there’s clearly been a huge decrease of thermal neutron flux since the
reactors were scrammed at t=0. And borated seawater was injected a day or so
later. But there are still some faster neutrons around, from spontaneous
fissions, for example, fissions of any Pu-240 that had built up in the fuel.

There’s also been a huge increase of the Cl-37 concentration in the coolant

The faster neutrons, those which are absorbed by the 10-B thermal absorption
definitely have smaller effective activation cross-sections on Cl-37 than
thermal neutrons. But not a zero activation cross-section.

So maybe it’s possible that the Cl-38 concentration in the coolant water has
actually built up to higher levels than normal due to the lack of cleaning the
huge inflow of salt with the seawater?

I’ld need to look at rate equations and cross-sections to make some kind of a
real estimate of the concentration of Cl-38 to be expected, given it’s
half-life. But if the equation has a positive overall coefficient then I
suppose that it may be possible … then it wouldn’t mean any re-criticality
of the fuel has occurred, and possibly the Cl-38 might not be so strange.

But if that’s the case, then they must see other activities in the water,
especially Na-24.


I’m not certain if this info has already been posted to this thread, if so my apologies. I’m moving a post over per Moderator request from the 26 update thread.


Barry & others re Plutonium.

Let’s not forget that Pu is also present from fallout. It seems pretty overblown for all the excitement, Kyodo report, etc., when the fact of detection isn’t even passed along with the concentrations – which was equivalent to that already present in the soil from weapons testing apparently.

I haven’t double checked the attachment’s but do note that they are there if you would like to check the actual reported amounts yourselves.

Press Release (Mar 28,2011)
Detection of radioactive material in the soil in Fukushima Daiichi Nuclear Power Station

On March 28th 2011, as part of monitoring activity of the surrounding
environment, we conducted analysis of plutonium contained in the soil
collected on March 21st and 22nd at the 5 spots in Fukushima Daiichi
Nuclear Power Station. As a result, plutonium 238, 239 and 240 were
detected as shown in the attachment.

We will continue the radionuclide analysis contained in the soil.

‹Results of the analysis›
-Plutonium was detected in the soil of Fukushima Daiichi Nuclear Power
-The density of detected plutonium is equivalent to the fallout observed
in Japan when the atmospheric nuclear test was conducted in the past.
-The detected plutonium from two samples out of five may be the direct
result of the recent incident, considering their activity ratio of the
plutonium isotopes.
-The density of detected plutonium is equivalent to the density in the
soil under normal environmental conditions and therefore poses no major
impact on human health. TEPCO strengthens environment monitoring inside
the station and surrounding areas.
-We will conduct analysis of the three additional soil samples.

attachment1:Result of Pu measurement in the soil in Fukushima Daiichi
Nuclear Power Plant(PDF 80.9KB)
attachment2:Fukushima Daiichi Nuclear Power Station Sampling Spots of Soil
(PDF 112KB)
attachment3:Fukushima Daiichi Nuclear Power Station Regular Sampling Spots
of Soil(PDF 135KB)


Some folks on other threads have been talking about some of the various isotopes detected, such as Ag-108, wondering where they’re coming from.

I would caution also that depending on the sampling methodolgoy, and the detection method used, and the relative abundance of various isotopes, it can sometimes be all too easy to accidentally identify an isotope incorrectly.

I suspect that the horrific EQ & Tsunami damage to the region (27,000+ dead or missing – god knows how many injured) with the nuclear plant crisis on top of it has got to make those sorts of errors more likely rather than less, unfortunately.

Anyhow, keep in mind that spent fuel rods in intact fuel bundles aren’t the only thing stored in the spent fuel pools. There typically might also be control rods, damaged fuel rods, used incore detectors, highly irradiated RPV QC coupons, irradiated reactor internals, and so on. All of these could be sources of various radionuclides.

Then from within the reactor core, there is not only the fuel, but of course zircalloy cladding, stainless steel, control rods, various instrumentation, iconel, any impurities in your water, and so on.

For some more detailed information at least on species, and just as an example see:

Note the Cl-38 that some of you were really wondering about:

There are numerous water activation products and activated water impurities in the coolant (Table 2–4). Among those nuclides, only a few nuclides are radiologically significant in reactor operation. The following activities have been studied in detail: H-3, N-13, N-16, F-18, Na-24 and Cl-38. The chemistry of nitrogen activities and their transport behavior in the steam/condensate systems in a BWR has become an interesting and important subject of investigation under hydrogen water chemistry conditions(1).

There are many other pages there that I suspect you’ll find of interest too.


It could be just me, but the claims that chronic radiation can be beneficial to humans, on the surface at least, sound awfully similar to the claims made by PG&E about hexavalent chromium in water being beneficial.



To answer a q. above:

A few go to “health mines” in Montana that have elevated radon. There are 3 or 4 of these. There are some in Germany and the Czech Republic also.

A few put natural (equilibrium) U-ore under the bed or in the office in small quantities i.e. few tens of grams..

Natural sources, basically…


@Rational Debate:

There are many other pages there that I suspect you’ll find of interest too.

Excellent link, thanks! So it seems Na-24 and Cl-38 do have to be dealt with by the reactor water cleanup system, and the rate equation I need is equation (2-3) there.


Since there is so much panic and forceful calls going on for closing down nuclear energy, I am wondering if there are distinctive differences between the Iodine and Cesium that has drifted around the world and the Plutonium now detected in terms of ease of travel. What can we predict? Is it too heavy to lift up in a light breeze, a strong breeze, a strong wind? Is it too heavy to get into winds that travel across the Pacific to land in the US? If it did travel, is it any more dangerous as a carcinogenic than Iodine and Cesium 137 or about the same? It is spoken of – by Helen Caldicott, for instance and thousands of others like her, as the ultimate threat, capable of condemning everyone to Leukemia in 5 years’ time if they so much as inhale one particle.



I’ve never heard of PG&E claiming that hexavalent chromium is beneficial before. That sounds pretty laughable. Got any references or pointers to read up more about that?

Radiation hormesis and the failure of LNT to agree with the empirical evidence isn’t a matter of “claims” – look at the empirical evidence.

The Nuclear Shipyard Worker Study…

The Taiwan Co-60 contamination in the buildings…

Extremely high natural geological background in places like Ramsar,..

The 2008 study which was published in Health Physics regarding radon exposure in Worcester county, Massachusetts…

There is a heap of empirical data out there that seems to indicate that LNT isn’t reality.


It’s not about LNT vs hormesis, its about the existence or nonexistence of a threshold below which ionizing radiation is harmless.

The hormesis issue is quite separate.


Hank Roberts, on 29 March 2011 at 12:14 PM:

With regard to the major radiation accident in Taiwan,
I cited Luan’s paper (as a .pdf) in an earlier post, so rather than keep posting the same old thing, this time I used his Powerpoint presentation that is aimed more at the general public than scientists.

In North Carolina, regulations permit 5 Rem/year for deep dose radiation and 50 Rem/year for weakly penetrating radiation (e.g Alpha and Beta).

The main problem with Alpha and Beta radiation is ingested material. In this situation Alphas are particularly dangerous which is why they are accorded a Q factor of 20.

Some years ago my employer had 20 Curies of Tritium. No, that is not typo. We were very concerned about treating individuals who ingested dangerous doses. The recommended treatment was to ingest beer until the Tritium levels fell to safe levels. This could take some time!

As a radiation worker my exposure to radiation was recorded for many years and I was well aware that there could be beneficial as well as harmful effects. Nevertheless, I always worked to keep my dosage to a minimum as the effect of ionizing radiation at low levels is not well understood.


Re: PG&E and hexavalent chromium

As I said, “on the surface” they seemed similar. So the devil is definitely in the details and language.

A couple references:

But in the interests of keeping the discussion on topic, I’ll let you have the last word if you want and won’t defend the analogy.


Caroline Webb,
You sound like my sister who lives in London. Recently she has been approaching a state of hysteria owing to the alarmist stories concerning radiation from Fukushima published in the British newspapers.

I have been wondering how to reassure her and the best I have been able to come up with is the following:

Q1. How many people in Japan died because of the March 11 tsunami?
Answer: More than 10,000.

Q2. How many people in England died?
Answer: None

Q3. How many people died as a consequence of nuclear fall out following the tsunami hitting 11 nuclear reactors in Fukushima?
Answer: None

Q4: How many people in England will die from radiation attributable to Fukishima?


It feels like Basil Fawlty has issued a new directive ‘don’t mention coal’. For example the word ‘coal’ doesn’t appear once in this news item on a takeover battle by mining company Rio, but it’s really 100% about coal. Obviously not a polite subject to be brought up at the dinner table.

I suspect the psychology of don’t-mention-coal applies differently in Australia compared to Germany for example. Aussies simply haven’t thought that hard about the cost and limitations of renewables. Perhaps carbon tax will be viewed as an indulgence payment as George Monbiot once suggested. As in we depend on coal but we’re paying the fine we’re cool. In Germany however I suspect most people know their energy mix is financially and physically unsustainable. However for now and a few years more they will tell themselves it will get better.


Scale of disaster in terms of just how high and how much water, how far inland. From stories at:

Tsunami flooded 100 square kilometers of city land

A survey has found that a quarter of the land ravaged by the March 11th tsunami was in cities and towns. The damage to urban areas is likely to greatly hamper reconstruction of these communities.

The semi-public Geospatial Information Authority says the tsunami flooded a total 443 square kilometers of land in the 4 prefectures of Aomori, Iwate, Miyagi and Fukushima.

Roughly a quarter of these areas, spanning 101 square kilometers, were commercial and residential parts of cities and towns.

Higashi-Matsushima City in Miyagi Prefecture had 63 percent of its land flooded by the tsunami.

The waves also swept through about half the town of Otsuchi in Iwate, and about 46 percent of Ishinomaki City and Yamamoto Town in Miyagi.

It will be a great challenge for these municipalities to clear space for temporary housing and rebuild vital infrastructure.

Tuesday, March 29, 2011 09:58 +0900 (JST)


GPS wave recorders off coasts recorded tsunami

A government study has found that dramatic changes in tide levels in the sea off northern Japan continued for about 6 hours after a massive tsunami struck on March 11th.

The land ministry survey relied on 7 floating GPS wave recorders installed off the Pacific coast from Aomori to Fukushima Prefectures. The Port and Airport research Institute analyzed data from the recorders.

One recorder about 20 kilometers off Kamaishi City, Iwate Prefecture detected tsunami waves right after the massive quake began.

A tsunami as high as 6.7 meters was observed by the recorder about 25 minutes after the quake. The tide level then fell by about 10 meters in about 30 minutes.

Researchers say the data may correspond to powerful drawback waves that swept buildings and vehicles into the sea.

Drastic changes in tide levels continued for about 6 hours, with 1- to 2-meter waves repeatedly observed.

The researchers say the data is vital, because most coastal tide observatories were destroyed by the tsunami and failed to yield any data. The data will be used to devise future counter-disaster measures.

Tuesday, March 29, 2011 11:49 +0900 (JST)

and finally:

Tsunami raised water levels over 40km inland

Japan’s Land Ministry has found that the tsunami on March 11th ran more than 40 kilometers upstream from river mouths.

The ministry collected data of water levels from major rivers in the affected areas and calculated how far the waves traveled upstream.

The records show that the water of the Kitakami river in Miyagi Prefecture rose by 11 centimeters about 49 kilometers inland nearly 3 hours after the earthquake.

The Tone river rose by 30 centimeters at a point more than 44 kilometers from the estuary.

The ministry believes the waves would have reached further upstream if all the floodgates had been open. 6 of the 9 gates located 18 kilometers from the shore were closed when the tsunami hit one of Japan’s longest rivers.

The tsunami caused severe destruction along a river several kilometers inland from the coastline.

Tuesday, March 29, 2011 02:22 +0900 (JST)


re post by Frank Kandrnal, on 28 March 2011 at 8:56 PM

Frank, for your hypothetical system, please tell me how you switch over all the necessary valves in order to transition from the normal operating configuration into the decay heat turbo driven system. (by he way, you might look up the BWR Reactor Core Isolation Cooling System).


I would like to ask the experts a question that I raised before , but which was not answered. It was a hypothetical question:

What would have been expected to happen had no attempts been made to cool the reactor cores with extraneous water? (I am not asking about the spent fuel transfer pools which were not in containment.)

I had understood (before this incident) that all the water in the reactor vessel would have turned to steam which should have escaped through automatic pressure release valves, leaving a dry reactor vessel. The loss of (unfiltered) steam would have allowed some volatile radioactive substances to escape (as happened anyway). Lack of fluid in the reactor vessel would have led to oxidation of zircalloy (assuming an adequate oxygen supply) which might or might not have “caught fire” and a total melt of fuel rods which would have dropped to the bottom of the vessel. What then? Would the hot fuel have been contained or not? Would pressure from hot gasses continue to allow the release of radioactive materials through pressure release valves for a time or would the pressure be insufficient to activate such valves?

In the design of this type of reactor, was a total core meltdown supposed to be containable? If so, is it reasonable to suggest, with the benefit of hindsight, that attempted sea water cooling made the radiation release to the environment worse rather than mitigating it? If the design wasn’t meant to cope with the consequences of total meltdowns, are more modern LWR designs? (I’m not talking of passive cooling etc, but of a total failure of cooling).

Finally, we have been led to believe that fourth generation designs, operating at pressures not much greater than atmospheric, will be safer and will require less expensive containment. Does this conclusion require re-evaluation?


I’ve been trying to think of a way to convert nuclear energy directly into electricity without heat/steam/gas/electric generators.

There was some talk recently (months ago) of using photomultiplier/photo-electric cells to convert decay energy into electricity. That would be much more efficient than current nuclear plants or even 4th generation nuclear though total power output would probably not be up to city demand requirements.


SHould have put a “bold face label” in my previous comment like “5th generation nuclear”.

(I think it would be 5th generation).


Douglas Wise: The way I understand it is that a complete core melt (a la Three Mile Island) would have been bad from the point of view of radiation release (note – if correctly contained, not so much release of radioactive material!), and also from the fact that the reactor itself would be completely unsalvageable.

The crews at Fukushima are trying to prevent a major release of radiation, of course, but that’s a comparatively remote possibility. However, they want to salvage as much of the reactor as possible. For example, the less damage the fuel rods receive, the more likely that some of the fuel pellets may be able to be reprocessed into usable fuel rods.

That said, I’d say that there’s not much that’s less than a complete write-off at the moment . . . .


Prices will rise, with or without tax: Garnaut

Professor Ross Garnaut says a price rise from a carbon tax will be small compared to the recent surge in power prices because of an over-investment in electricity networks.

Can someone who has more knowledge on such matters decipher this for me? It makes no sense. Over-investment in energy technology in Australia?!


konst: There was some talk recently (months ago) of using photomultiplier/photo-electric cells to convert decay energy into electricity.

You mean like photovoltaic cells – aka solar cells?

Hmmmmm. Seems to me we already have the engine for that in the form of this big yellow thing that comes up in the morning and goes down in the evening.

Maybe we could use that and bypass a lot of the capital cost (and risk)?


Douglas Wise’s query of 29 March 2011 at 6:51 PM strikes me as a very important “baseline” issue. It is so crucial that it must have been extensively discussed by designers at GE (etc.) and by regulators at the NRC (etc.). It would be useful to understand the expert consensus, if any, on the fate of an uncooled BWR core in its containment vessel.

Johno — your response to Douglas Wise (29 March 2011 at 7:43 PM) seems to be speculative. It would be helpful if you would cite the authorities that back up your view.


Nuclear Photoelectric Powerplant
@ JM, on 29 March 2011 at 10:45 PM,

Well the sun don’t shine 24/7 and the sun’s energy is too diffuse to use in a practical way as an energy source for a city.

No I don’t mean solar cells. Solar cells operate on specific frequencies of sunlight.

Photoelectric cells operate at various energies/frequencies to match what the radioactive elements emit.
Those radioactive elements emit 24/7/365. No need for huge back up storage systems.


@ Douglas Wise
An NRC study on Reactor Safety
(Severe Accident Risks: An Assessment for Five U.S. Nuclear Power Plants — Final Summary Report (NUREG-1150, Volume 1) included Peach Bottom 2, a GE BWR with a Mark 1 Containment Structure, the same containment as the affected units as Fukushima. The relevant scenario here is Loss of Offsite Power (LOSP). Figure 4.6 on page 4-14 of the report indicates that the conditional probability of early containment failure for this scenario has a mean value of somewhere between 0.6-0.7.

While I agree that the highly contaminated water is a difficult issue to resolve, it appears likely that a decision not to continue to cool the reactor would have had much more severe consequences.


i have been following this blog since the original post that was trying to reassure me and didn’t, the one that was then, by barry’s own words, proven wrong.

last night i posted my responses on my own blog. the gist: i am concerned when i don’t see a deeper willingness to consider assumptions and predictions when the prediction proves wrong, and things keep getting worse at fukushima.

i don’t see a way to distinguish between error in a local prediction and errors in the overall thinking and prediction about the role of nuclear. i am desperately wishing for some humility.

anyone who wants to read more, please go to


I think others have mentioned the document containing Pu soil measurements –

It seems to me that the concentrations of Pu in the soil around the site are unremarkably low – note that the MEXT standard levels for “ordinary domestic soil” are:

Pu-238: 0 – 0.15 Bq/kg
Pu-239/240: 0 – 4.5 Bq/kg

The highest amounts detected of each nuclide were (5.4 +- 0.62) x 10^-1 Bq/kg for Pu-238 and 1.2 +- 0.12 Bq/kg for Pu-239 and Pu-240.

Is it just me, or are those levels unsurprising/underwhelming? We’re talking almost 2 seconds/kg between Pu-238 decays.


NPP, the baseload argument doesn’t work. Have a look at the demand curves. Nighttime demand is about 1/2 that of daytime so there is no need to run generators full whack 24 hours a day.

The only reason why we do is that coal (and nuclear) fired plants can’t be cycled over that timescale. This is also the reason for “off peak” electricity, the surplus power would otherwise be lost.

Further you suggest that sunlight is too “diffuse”. Rubbish. How diffuse do you think decay heat is? Very. Essentially you have no more energy out of it than you do out of natural uranium.

(This also has an impact on your very silly suggestion of using photomultipliers – photomultipliers are amplifiers, a small signal comes in and is amplified by power supplied to the device so that its output is large enough to drive a detector of some sort.

In other words, most of the output from a photomultiplier comes from external sources, it just happens to track the input signal.)

As for photoelectric cells I think you’re equally confused. I suggest you start with Einstein’s original paper on the subject – which is an absolute masterpiece BTW – it might help you a bit.

The facts are that sunlight is not diffuse or you wouldn’t be able to see your hand in front of your face at noon, and that decay heat is.

No. If you’re going to use radioactive sources for energy generation you’ve basically got to use fission. Maybe fusion in the future, but they’ve been saying that for 50 years now and we’re no closer


And, gad, history surfaces.
has a link to
Sep/Oct 2002 No.9 Nuke Info Tokyo p2

“… Industrial Safety Agency (NISA) announced at a press conference that TEPCO had falsified voluntary inspection reports and concealed it for many years. TEPCO admitted the stated facts at the press conference later in the same day. According to the agency, TEPCO has falsified the inspection records and attempted to hide cracks in reactor vessel shrouds in 13 units of the 17 nuclear power plants owned by TEPCO, including Fukushima I (6 reactors), Fukushima II (4 reactors), and Kashiwazaki- Kariwa (7 reactors). However, the agency maintained that there should be no problem regarding the safety of the nuclear power plants. Ironically, the safety assessment by the agency was based on TEPCO’s calculation.
The TEPCO’s wrongdoings were exposed as a result of a whistle-blowing by a former engineer at General Electric International Inc. (GEII) in information given to the then Min- istry of International Economy and Industry (MITI) (the former body of the Ministry of Economy, Trade and Industry, METI) on July 2000. The tip-offs revealed the falsification of inspection records regarding cracks in a steam dryer, as well as the attempt to hide the repair work for the cracks by the editing of video tapes. This insider’s information was never taken seriously by the then MITI (after Janu- ary 2001, the NISA took over administrative authority from the METI) and the case was left virtually untouched for two years. “We needed a time to protect the status of the whistle-blow- er and we didn’t know whether we had the right to investigate the case,” said the agency after the press conference on August 29. On the con- trary, it was found later that the METI leaked the whistle-blower’s name to TEPCO, which clearly suggests the Ministry failed to support the person who blew the whistle on corporate corruption. While TEPCO had not taken any appropriate measures against the insider’s tip- offs, it set up a special joint inspection group in conjunction with GEII on May 2002 to inves- tigate the case, suspecting that there might be more falsification cases in the company.
It has been confirmed that there are 29 cases of falsification, which were related to dam- age in many parts of the reactor pressure vessel such as core shroud, jet pump, access hole cover, feed water spurger, on-core monitor housing and others. The NISA and the TEPCO published interim reports on September 13 and 17 respectively, which addressed the 29 suspected cases in more detail. Regarding the cracks detected in the core shroud, according to the report, they had been already found at Fukushima I Unit-1 and Unit-4 in 1993, where the cracks in the middle part of the shroud at Fukushima I Unit-2 in 1994 were reported officially as the first case. The magnitude of the cracks in Fukushima I Unit-2 turned out to be far greater and more serious than the ones announced by the official report. It has also become clear that reactors in Fukushima I Unit 1, 3, and 5 have cracks in each shroud, so the claim that no cracks were found in the core shrouds and that they were replaced as a “preventive measure” is completely false.
It is reported that cracks were found in the core shrouds of Fukushima II Unit 2, 3, and 4 and Kashiwazaki-Kariwa, 1 and 3, which is composed of the anti-stress collision crack material (SUS316L) after 10 years of their operation.
It is now clear that there were more than 29 falsification scandals.
On September 20, other damage cover-ups in the re-circulation pipe system were revealed in TEPCO’s eight nuclear reactors, as well as Onagawa Unit-1 of Tohoku Electric Power Company and Hamaoka Unit-1 of Chubu Electric Power Company. In addition, other cracks in the core shroud were found at Ona- gawa Unit-1, Hamaoka Unit-4, Tsuruga Unit-1 (Japan Atomic Power Co., Ltd), and Shimane Unit-1. As has been pointed out, this series of cover-ups showed the scandal was not merely TEPCO’s particular problem but involved most of the nation’s electric companies.
Electric companies have made most data falsifications during voluntary inspection. There have been a growing number of damage cover-ups and data falsifications around 1994 when electric companies had started shortening the time for a periodical inspection having learned from the “success” experience in the U.S….”



I am extremely grateful for your link. I find it fascinating that Fukushima events, consequences and probabilities had been studied well in advance by a theoretical analysis of what could have happened to Peach Bottom 2.

This is, in some ways, very reassuring. It also tends to explain why the plant operators are acting as they are. Simultaneously, it demonstrates that there were lessons that could have been learned (hindsight) that were not learned.

The link deserves a great deal more attention and I have, as yet, been unable to assimilate all the information contained. It may still defeat me, given my lack of technical expertise. However, it is the single most valuable cite that I have looked at. Thank you, once again, and I will attempt to study it in more detail in the near future.


there are reports about the conditions of workers in the plant in the news today.,0,319767.story

i was really shocked when i read this first. and i must say, if only a single word of this is true, then we are either facing a problem that is much more serious than any of us thought (because conditions are so problematic, that they can t handle it in a different way) or we experience incompetence of epic proportions.

i come from a military background, and my first thoughts when i heard about the “heroic 50” workers left on the plant, was about shifts, objects and how to accommodate them.

with 6 reactors and 3 shifts, we would get a rather tiny group of 3 people. (this could explain how stuff could go out of control, while focus was elsewhere).

i was expecting the army moving in, with containers and decontamination vehicles. i would expect a shuttle service to off-site accommodation for the workers, where they can decontaminate, refresh and get supplied.

obviously nothing of that sort is happening. this is quite unbelievable!


If seawater injection to primary circuit had not been possible then they would have attempted to flood only the drywell and retain and cool the near full core melt in-vessel. If that had also failed the core would have melted through the vessel into the bulb space below which is designed to arrest core meltdown but I am not sure if it would contain a full core meltdown. It possibly could but you would get loads more volatile fission products in the environment and it goes against the defense in depth strategy to retrench to the next layer of safety – the full core melt retaining in the drywell is your absolute last layer of defense! Beyond that there is possibly lead or tin metal entombment (experience from Chernobyl would be used, eg no initial clay entombment but go direct to metal entombment).

I will try to find some references on in vessel corium arrest and retention for BWRs, its a long time ago that I read those…


Sod, don’t you read your own links? Your link says 400 workers with reinforcements that have come in. Daiichi 5 and 6 require only skeleton crew. So 400 for 4 reactors.


How about this?

No fears about a zunami or emissions to the atmosphere. Cooling water always “behind the wall”, just open the hatch.

And what is most interesting – could they be built outside the sea frontier of some country? Put a dozen of those in the bottom of North Sea and wire them to Denmark. Just as an example.


Reading that 2001 report, all the info we have been reading about how the containment should behave is based on theory, not on the actual condition of these reactors — is that right?

When I read

“The magnitude of the cracks in Fukushima I Unit-2 turned out to be far greater and more serious than the ones announced by the official report. It has also become clear that reactors in Fukushima I Unit 1, 3, and 5 have cracks in each shroud,…”

and look at how at the time they put bolts on the outside to hold the pieces tight — I wonder what the heat did to those patches? Or was anything else done since?


“Sod, don’t you read your own links? Your link says 400 workers with reinforcements that have come in. Daiichi 5 and 6 require only skeleton crew. So 400 for 4 reactors.”

of course i read my links. the first claim was about 50 workers. now they are more.

there are 6 reactors and we really need to keep the 2 that are less problematic from going out of control. if you want, count them half, but please don t ignore them.

with 400 people (about battalion size) i would expect about 20-25% to be pure logistics, there to support the rest without being involved in the actual work at all.

that still leaves you with only around 20 workers per reactor.


but the more important points are other ones. do you understand the meaning of “no running water” in such a contaminated environment?!?


Has some interesting information about robots being sent over from the US. Apparently these were developed in the wake of TMI.

The article paints a picture of chaos and confusion on the ground with the head of Tepco being MIA for days. One of the more concerning parts, if true, is this:

“Lyons said US flights were only going within 2.5 miles of the plant, because of the elevated radiation levels.”


@ Tom Keen I think Garnaut has a valid point. The big rush by power companies to get general price increases started about 2007 when carbon pricing was on the agenda. Coincidence or what? I heard one power co. exec list a string of minor reasons for hefty increases as if one reason wasn’t enough. State governments who often own or milk these companies then gave the nod to their pricing tribunals. Perhaps the ACCC should investigate them for collusion.

In my opinion the electricity price rises were largely a pre-emptive grab for a pound of flesh before Federally imposed carbon pricing arrived. The States ganged up against the Commonwealth. This view was reinforced yesterday when a power co. exec denied repeatedly that aluminium smelters get a special deal. Of course they do … on direct orders of State governments.


U.K Guardian article today seems to have a reliable source commenting on meltdown fears.

Japan may have lost race to save nuclear reactor

Fukushima meltdown fears rise after radioactive core melts through vessel – but ‘no danger of Chernobyl-style catastrophe

“Richard Lahey, who was head of safety research for boiling-water reactors at General Electric when the company installed the units at Fukushima, told the Guardian workers at the site appeared to have “lost the race” to save the reactor, but said there was no danger of a Chernobyl-style catastrophe.”

“The indications we have, from the reactor to radiation readings and the materials they are seeing, suggest that the core has melted through the bottom of the pressure vessel in unit two, and at least some of it is down on the floor of the drywell,” Lahey said. “I hope I am wrong, but that is certainly what the evidence is pointing towards.”

Excerpts copied, please read the whole article.


Apologies, I posted the call for help on the wrong thread, best put here.

help … the ExternE report … a million pages or so keeps referring to mECU/kWh as an externality cost. Even google doesn’t know what an mECU is … I get plenty of hits but no definitions. Anybody know? Looks like life cycle analysis jargon.


@ David Kahana or others, re Cl-38 in samples

I’m not sure just what protocol or equipment (or even the time delay getting samples to the equip) would be over in Japan, but ran across this comment on another site and figured I’d toss it up for whatever it might be worth. It sounds plausible on the face of it to me (& we’ve all seen/used peak summing software), but I haven’t been directly involved in measuring super hot & relatively complicated effluents like this. (for folks reading who may not be familiar with some of the verbal shorthand, I’m meaning hot in terms of radioactivity here, not temp)

Anyone know enough to knock it (or support), please share!

Frankly errors of this nature sound far more likely to me than any chance of re-criticality – not to mention as others already have that then we’d be seeing other isotopes also that weren’t in the sample results, and the relative abundances don’t seem plausible, etc.

So the comment from someone else on another site was:

I am quite convinced that the chlorine-38 number was due to the same error as the spurious I-134 activity.

It takes time for them to get the samples to the gamma spectrometer. That gamma spectrometer uses smart software to identify peaks in the spectrum, using a database with the kind of stuff that may be present in a nuclear power plant.

But there are lots of peaks. Because of the high count rates, there will also be accidental summing peaks of two strong gamma energies. The program then identifies some small spurious peak as Cl-38.

What is more, the program will calculate numbers for the time the sample was taken. It corrects for decay. In the case of these rather short-lived isotopes, those corrections may be as large as a factor 1000.

Such extrapolations backward are nonsense of course, but the lab guy just takes the computer output for granted.

I do not think there ever was any Cl-38 in the spectrum.


@Geoff Russel
I guess it might be an externality correction unit, a means to calculate with otherwise incompareble externality costs. But i have no idea how big it would be. mECU would be one on thousand. It would then be the costs payed by others than producer or consumer after some standard. Some steady currency or precious metal or so.

We do the same thing with milk. Not all cows give the same quality milk, so the farmer gets payed price per kilo ECM. Thats where the guess is from.


Double breaches at Fukushima Daiichi No. 2?
Former US Navy Reactor Operator Will Davis blogs at Atomic Power Review. Yesterday he offered analysis of the evidence for reactor leaks at Daiichi No. 2. What can we infer when we observe a volume of contaminated water exiting the “controlled area” – which volume is almost as large as the volume of water being injected for core cooling?
If the inference is correct, then I have to agree with Will’s point that it is time for “a good solution applied vigorously”.


Double breaches at Fukushima Daiichi No. 2?
Barry Brook tweeted the link to this article, which was originated by anonymous poster KBMAN on daily Kos. I’ve not posted anything at BNC on the KBMAN diaries as thought Barry would post something if he found the source credible. But we know Barry is just wee bit busy, so check it out, see what you think.
I’ve done a quick survey of KBMAN’s credentials and other writing on nuclear topics. My judgement is the writer is not a crank, he looks to know his subject, and intellectual integrity looks solid. I’ve assembled some KBMAN resources here, and here. Yes I know he is posting in an odd place to find informed commentary, but don’t let that stop you:-)


Double breaches at Fukushima Daiichi No. 2?

Nuclear chemist Cheryl Rofer retired from Los Alamos National Laboratory, where she worked from 1965 through 2001 on the nuclear fuel cycle, management of environmental cleanups, and other topics. [more bio details at the end of this post]. She posts at the British Medical Journal group blog and at her own group blog Phronesisaical.

Is There a Leak at Fukushima #3? is especially relevant to my concerns re: reactor leaks. At the time of writing Cheryl thought that any leak must be small as RPV pressure is holding.


Leave a Reply (Markdown is enabled)

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s