Merged nuclear power safe?

[MattusMaximus]

But *I* have received no formal science education since I did my A-levels, where I took biology, and I haven't done physics since I was 16, 7 years ago. Why is it that I understand basic nuclear physics but reporters who are supposed to be just as educated as me do not?

Because you are concerned about getting it right, as opposed to getting it first. Sadly, many in the media place their priority on the latter, I think.

 

[MattusMaximus]

Not being an expert I'm a little concerned that things tend to be appearing to be getting worse rather than better. Shouldn't the cores actually be cooling down?

First, you should be concerned - it is a serious situation. However, the severity of the situation is basically limited to the immediate area around the Fukushima site. So, in that sense, concern should not give way to the hysteria & panic being spread by too much irresponsible reporting.

Second, some of the cores at Fukushima have cooled down and been completely shut off. The updates I'm watching seem to indicate the bulk of the trouble is with the remaining one or two that haven't been successfully cooled down.

Hard to tell the real situation with so many conflicting reports going round though.

I agree. In their rush to "get it first" as opposed to "get it right", the media has more than contributed to that problem. No wonder the public is freaked out.

The BBC saying that the Japanese have increased the 'safe level' for plant workers from 100 to 250 milli sieverts which doesn't sound good to me.

Regardless of what the BBC is saying, there is no doubt that it is going to really suck for the plant workers and others on that site trying to clean up this mess.

 

[armageddonman]

http://www.cnn.com/2011/US/03/16/japan.west.coast.fears/index.html?hpt=C2

Well, looks like Germans are not alone in their idiocy.....

 

[bobdroege7]

Yes, and I keep seeing/hearing people go on and on about how Fukushima "is now a 6 on the INES", but I can find no confirmation of that beyond some speculation in an article in Germany (which I think has been misrepresented on Wikipedia). The last estimate I saw from the proper authorities is that Fukushima is still a 4 on the INES.

Anyway, if anyone wants to know more on that point, I updated my blog last night about it. Also, if anyone can find actual, reliable confirmation that the INES rating of Fukushima has indeed gone up, I'd like to see it.

So this isn't happening

"Significant release of radioactive material likely to require implementation of planned countermeasures. "

They are evacuating the area, which would be a planned countermeasure consistent with 6 severity accident.

Those hydrogen explosions indicate that containment has failed, the containment buildings are no longer containing the accident.

It's been worse than TMI since the power was lost and the cores have become partially or fully uncovered, and TMI was a 5.

It doesn't do any good to underestimate the severity of this accident any more than it does to overestimate it either.

 

[Last of the Fraggles]

So this isn't happening

"Significant release of radioactive material likely to require implementation of planned countermeasures. "

They are evacuating the area, which would be a planned countermeasure consistent with 6 severity accident.

Those hydrogen explosions indicate that containment has failed, the containment buildings are no longer containing the accident.

It's been worse than TMI since the power was lost and the cores have become partially or fully uncovered, and TMI was a 5.

It doesn't do any good to underestimate the severity of this accident any more than it does to overestimate it either.

Has the bit in bold actually happened?

 

[Aepervius]

@bob that is not quite correct.

INES 5:
Impact on People and Environment
Limited release of radioactive *material likely to require i*mplementation of some planned* countermeasures. No, not as far as I read from the Japan report
Several deaths from *radiation. None

Impact on Radiological Barriers and Control
Severe damage to reactor core.No, not as far as we were told
Release of large quantities of radioactive material within an installation with a high probability of significant public exposure. This could arise from a major criticality accident or fireNo

As far as I can tell none of that apply, so sorry, but from what the japanese autorithy said, it is still a 4.

 

[Aepervius]

Has the bit in bold actually happened?

There was a short spike of 400 mSv/hour, but to call that *significant* would be using a very conservative definition.

That one seem to be more applying:
Minor release of radioactive material unlikely to result in implementation of planned countermeasures other than local food controls.

 

[MattusMaximus]

Yes, and I keep seeing/hearing people go on and on about how Fukushima "is now a 6 on the INES", but I can find no confirmation of that beyond some speculation in an article in Germany (which I think has been misrepresented on Wikipedia). The last estimate I saw from the proper authorities is that Fukushima is still a 4 on the INES.

Anyway, if anyone wants to know more on that point, I updated my blog last night about it. Also, if anyone can find actual, reliable confirmation that the INES rating of Fukushima has indeed gone up, I'd like to see it.

So this isn't happening

"Significant release of radioactive material likely to require implementation of planned countermeasures. "

They are evacuating the area, which would be a planned countermeasure consistent with 6 severity accident.

Those hydrogen explosions indicate that containment has failed, the containment buildings are no longer containing the accident.

It's been worse than TMI since the power was lost and the cores have become partially or fully uncovered, and TMI was a 5.

It doesn't do any good to underestimate the severity of this accident any more than it does to overestimate it either.

Did you miss the part where I asked for "actual, reliable confirmation"?

 

[Nosi]

More than likely, yes, that's exactly what they think. If Dutch journalists are anything like ours in Finland, the young generation will have a degree in journalism, social sciences, and/or humanities, the older generation will mostly be dropouts. It's highly unlikely that they have received any science education after they left high school/gymnasium.

Exactly. I left school (junior college) qualified for starting a journalism career with a shiny AA degree and I know pink squat about nuclear reactors. Plop me near one, I might be able to find the bathroom but that's it. Then again, I'm honest.

 

[Aepervius]

@bob anyway the evacuation CANNOT be taken as a counter measure, as they use it in a preventive measure. You are just blowing hot air here, jsut like the french guys.

 

[Eddie Dane]

Sorry that I have to say this, but this is ignorant on several levels.

The containment building is designed to contain the radiation and contamination, but it is a rather large structure with many piping penetrations which are sealed with materials that range from robust to rather flimsy.

I say flimsy because I know what I am talking about having acually sealed such penetrations at a BWR-6 plant simular but probably a bit more robust than the ones in Japan.

A BWR-6 has a drywell and a Containment building rated at 30 and 15 psi, if memory serves.

When you don't have emergency cooling capacity for an extended period of time following a shutdown, the pressure in the reactor vessel rises, until a set pressure is reached, which caused valves to open to relieve that pressure, from the reactor vessel to the containment building. The suppression pool actually, a large pool of water at the bottom of the containment building.

The hydrogen explosions indicate that the containment system is no longer "containing" the core elements.

This is way beyond what the containment system is designed to be able to withstand. The emergency cooling and containment systems are simply not designed to handle this without electrical power.

These systems are designed to prevent a meltdown, not contain one after the fact.

I'm far from an expert, but a thirty centimetre thick concrete + steel containment vessel sounds flimsy to me.

As I recall, modern reactors have vessels that are metres thick.
Mostly to stop impacts from rockets etc. but still.

Is this thing expected to be as effective as the vessel at Three Mile Island?

 

[DC]

I'm far from an expert, but a thirty centimetre thick concrete + steel containment vessel sounds flimsy to me.

As I recall, modern reactors have vessels that are metres thick.
Mostly to stop impacts from rockets etc. but still.

Is this thing expected to be as effective as the vessel at Three Mile Island?

what vessel are you talking about?
neither the vessel (30mm) nor the containment (1.5m) is meters thick. Maybe the concrete surrounding the 2 is. But where did you get that from?

 

[KoihimeNakamura]

He said 'modern' reactors.

 

[Bluespaceoddity]

Please have a look at this animation from Dutch television.

It shows what went wrong (loss of coolant, emergency coolant injected), but also shows what would happen in case of a meltdown.

The reactor vessel is on 30 cm thick (according to this news item).
The reactor building has a hole in it.

based on this information, it looks like a meltdown would result in quite lot of radioactive material escaping the building, not just causing a huge molten mess in the reactor vessel as many here claim (if I remember correctly).

Can those in the know enlighten me?

ETA:

http://nos.nl/video/225894-wat-gebeurde-er-precies-bij-de-explosie-in-reactor-2.html

I think it may be important to add to your summary that the video also shows that one of the explosions in reactor 2 occurred in the "condensatievat", what bobdroege7 just described as: "The suppression pool ... , a large pool of water at the bottom of the containment building." and has also been identified as "Torus" in some cut aways of the building posted earlier in these threads.

That corresponds with information from Japanese TV where it is given as one of the possible explanations for why the "Containment Integrity" of reactor 2 is still listed as "Suspected Damaged" in JAIF's status estimates. Either the "suppression pool" or the pipes and seals leading in/out of the "suppression pool" may have been damaged in the explosions. Explosions possibly resulting from the venting of Hydrogen gas rich materials from the interior of the reactor in efforts to alleviate pressure increases after the fuel rods were insufficiently cooled etc as described in the video...

Any of the JREF experts - I'm not- can probably tell you more about that in their continued effort to share accurate information ...

JST 19:00
http://www.jaif.or.jp/english/news_images/pdf/ENGNEWS01_1300273535P.pdf

These experts may also offer a comment on the design of the storage pools inside these buildings and explain what the conditions may be for fuel rods in these facilities outside the main "reactor containment vessels" based on the current state of these buildings and the stated availability of coolant ....

 

[bobdroege7]

I'm far from an expert, but a thirty centimetre thick concrete + steel containment vessel sounds flimsy to me.

As I recall, modern reactors have vessels that are metres thick.
Mostly to stop impacts from rockets etc. but still.

Is this thing expected to be as effective as the vessel at Three Mile Island?

I think they are more than 30 centimeters, more like three feet, but I was talking about the penetration seals, which are smaller openings to allow pipes to penetrate.

Those holes are sealed with materials ranging from two part cured expoxies of various densities to reinforced rubberized fabrics attached with hose clamps.

They are not designed to take high pressures.

 

[dudalb]

Are you sure it wasn't microsieverts? Living in 0.6 mSv per hour for a while would either make you very sick or turn you into Spiderman.

Depends on the dosage you get. If you get a lot you turn into the Incredible Hulk......

 

[bobdroege7]

@bob anyway the evacuation CANNOT be taken as a counter measure, as they use it in a preventive measure. You are just blowing hot air here, jsut like the french guys.

Yeah right,

If the rad levels are 60 mrem per hour at the site boundary, evacuation of the surrounding area would be considered the required countermeasre, just because they did it beforehand as a preventative measure doesn't mean it is not required now.

A reading like that at the site boundary would also indicate the release of a significant amount of radioactive material.

If significant has to be 0.1% of the core load, then no, we don't have reliable information to assess that.

But then again, the spent fuel pool was reported to be on fire, then put out, then on fire again.

And that is not contained.

Maybe the French guys know something about commercial nuclear power and the design and construction of the emergency safety systems involved.

I used to maintain these systems, I am not blowing hot air.

 

[dudalb]

They don't, but look at my anti-radiation crystals (only €449/piece, or €2499 for a family-size pack of five! Order now and get yours before the Wind of Death decimates your neighborhood!)...

Sad thing is, you know that Scam Artists are going to come up with something like this...and that people will buy it.

 

[BenBurch]

This is a very serious event. Just about as bad as can happen with a BWR of that vintage if indeed containment is breached and actual core material has leaked.

Not nuclear devastation, but significant contamination that will be in the 100 billion range for remediation.

They will now have to sink coffer dams all around the site to limit groundwater and ocean contamination, and likely an evacuation zone in the immediate vicinity of the plant will be semi-permanent.

If we have a fuel fire, then this will get a lot worse.

 

[dudalb]

so organising 4000 people to send this letter to Obama on 4 days wasn't lobbying?

That none of the technologies they support is anywhere near ready for prime time seems to evade them.
This is a prime example of one trend that scares me:The whole "If Ideology conflicts with reality, then reality must be disposed of" mentality.