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Old 03-12-11, 09:21 AM   #1
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Default 8.9 Quake, Tsunami & Nuclear Accident In Japan

Japanese official says pumping system caused nuclear plant blast - CNN.com
Old 03-12-11, 10:27 AM   #2
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Default Re: Nuclear Accident In Japan

"...Boric acid will also be added to the salt water to fight a possible elevation in nuclear reaction, Mr. Edano said..."

Rings a bell...
Old 03-12-11, 12:19 PM   #3
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Default Re: Nuclear Accident In Japan

Talk to us BG....not meaning to put you on the spot, but would appreciate your thoughts and prognosis.
Old 03-12-11, 01:59 PM   #4
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Default Re: Nuclear Accident In Japan

Reports of iodine being readied for distribution...

Hot tip out of "Ablaze" by Piers Paul Read:
Quote:
don't drink that stuff in your first aid kit
Russian equivalent from same book: a tumbler(!) of vodka in the morning
Old 03-12-11, 03:43 PM   #5
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Default Re: Nuclear Accident In Japan

OK. How many idiots are there who contend that nuclear energy is clean energy? Disasters such as Chernobyl are one thing. History is yet to determine whether Japan may witness such a tragedy.

But, at the end of the day, nuclear plants produce "spent" material that will continue to be highly radioactive beyond our lifetimes.

Is this the clean energy we want or need?
Old 03-12-11, 05:22 PM   #6
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Default Re: Nuclear Accident In Japan

Made a trip out to the island today so I haven´t been keeping up...

What surprises me most about this event is the fact that the Japanese are considered to be safety conscious and yet their plant´s primary coolant system only had (in this order) primary (grid) power feeds, diesel generator and short term battery backup. We had more backup systems on our naval reactors at sea. Primary coolant flow through the core is required even after reactor shutdown or a scram event like what most certainly occured in this case. Even when in a shut down condition there is a residual amount of fission occuring and heat produced that must be dissapted.

Boric acid is one of the chemicals that can be used to help shut down the fission chain by flooding the core volume surounding the fuel plates with neutron absorbing agents.

If the fuel plates are breached this reactor will not see service again. If the primary vessel containment is breached this facility will become a serious cleanup problem and potential health danger to the nearby community. How big a danger will depend on what kind of secondary containment systems are built around the reactor.

This is not a Chernobyl type event by far as we are dealing with U235 here (if I heard the report correctly) which is much less dangerous than the U238 breeder type reactor used by the Soviets. U238 can continue to fission in the absence of coolant (H2O). U235 will not.

A theory exists that the best way to deal with this kind of plant emergency (at this point) is to simply void the entire primary coolant system. The water void will momentarily accelerate the heat damage to the core rendering it a total loss but in the absence of coolant it should completely shutdown. Water cooled reactors are safer as the coolant (water) is also a moderator, serving to slow down the neutrons from fission to a kinetic energy level where they can produce another fission event. In the absence of water the neutrons from fission are traveling too fast to cause another U235 atom to fission and will simply escape, streaming out from the reactor core and the core will cool down on its own.

This is possible in a U235 core but not in a U238 breeder core as U238 does not require ¨slow¨ neutrons to fission.

Plant engineers and utility owners would probably be slow on the draw of such a measure as it will render the reactor core, vessel and likely the primary containment a complete loss.

Will try and catch the news tonight to see what has happened.
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Old 03-12-11, 06:22 PM   #7
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Default Re: Nuclear Accident In Japan

I'd say, based on two other articles I read, that you sure know your stuff, BG. And I'd like to add that your explanation was more concise and straight forward.
I gather the back up systems were thwarted by the tsunami. I don't know enough but logic would tell me that even an increase in the number of power back-ops wouldn't necessarily nake a difference if they wer all drowned in sea water muck for 30 minutes. These folks are in a really tough situation, may their best be good enough.
Old 03-12-11, 06:33 PM   #8
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Default Re: Nuclear Accident In Japan

You know you're seeing the waning years of a mainstream media in decline when bloggers do a better job reporting/informing than they do.

Fukushima Explosion Update: Core Presumed Intact As Sea Water Used To Bring Temperature Down, Radiation Level At 1015 Microsieverts/Hour | zero hedge

On The Japanese Quake and Tsunami in [Market-Ticker]
Old 03-12-11, 10:04 PM   #9
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Default Re: Nuclear Accident In Japan

Wheels are really coming off now...

Posted March 13, 2011 15:41:00 AEDT (Sydney time)

"...the government is warning that meltdowns may have possibly occurred at two reactors...

...chief cabinet secretary Yukio Edano says it is possible the radioactive cores of the two damaged Fukushima reactors have already started to melt.

"We do believe that there is a possibility that meltdown has occurred, it is inside the reactor, we can't see," he said.

"However, we are acting assuming that a meltdown has occurred and with reactor No. 3, we are also assuming the possibility of a meltdown as we carry out measures."...

...Japan's US envoy insists there is no evidence the stricken nuclear reactor has gone into full meltdown, but acknowledges there has been a "partial melt" of a fuel rod.

"We do not see evidence of that at this time," ambassador Ichiro Fujisaki said.

"What our government has announced is that it was a blow-up of the outer building.

"There was a partial melting of fuel rod. There was a part of that... but it was nothing like a whole reactor melting down," he added..."

Partial meltdown likely at 2nd reactor - Google Search
Old 03-12-11, 11:16 PM   #10
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Default Re: Nuclear Accident In Japan

Hey, just curious.... what do ya do with 3 or 4 nuclear reactors in melt down

Gorilla Glue.... .................

Oh wait, maybe the whales will get a break .........
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Last edited by wessongroup; 03-12-11 at 11:22 PM. Reason: after thought
Old 03-13-11, 08:19 AM   #11
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Default Re: Nuclear Accident In Japan

"...It is essential to develop and install adequate instrumentation qualified for the radiological and accident conditions in order to diagnose the threats to the core cooling and confinement functions as well as to monitor radiological conditions inside the plant...
Quote:
"...chief cabinet secretary Yukio Edano says..."...there is a possibility that meltdown has occurred, it is inside the reactor, we can't see,"..."
...92. Systematic assessment of the implementation of defence in depth is performed throughout the lifetime of the plant, and account is taken of operating experience and significant new safety information from all relevant sources...insights about deficiencies from incidents or investigations (e.g. from operating experience...); consideration of equipment ageing; and the general extension of knowledge...

...4.2. LOW POWER AND SHUTDOWN CONDITIONS

109. As the main efforts were initially devoted to postulated incidents and accidents occurring mainly under full power conditions, the implementation of the different levels of defence was for a long time less systematic, and is partly still so, for low power and shutdown conditions..."

© IAEA, 1996

Found on
The Automatic Earth: March 13 2011: How Black is the Japanese Nuclear Swan?
Old 03-13-11, 08:21 AM   #12
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Default Re: Nuclear Accident In Japan

Quote:
Originally Posted by Bajahowodd
OK. How many idiots are there who contend that nuclear energy is clean energy? Disasters such as Chernobyl are one thing. History is yet to determine whether Japan may witness such a tragedy.

But, at the end of the day, nuclear plants produce "spent" material that will continue to be highly radioactive beyond our lifetimes.

Is this the clean energy we want or need?
Obama can direct Susan Rice to have the UN create a resolution that all nuclear power plants will be dismantled within two years and the IAEA will enforce the resolution. That should take care of your concerns.
Old 03-13-11, 09:42 AM   #13
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Default Re: Nuclear Accident In Japan

No doubt nuclear is dirty, dangerous, and expensive.

Assertions we should not employ it ignore the complete analysis: what are our realistic alternatives?

Coal, and complete dependence on foreign oil...Liquified Natural Gas?

Let's hear it for clean, safe, and cheap aspects of those.


The Oil Drum: Net Energy | The Energy Return of Nuclear Power (EROI on the Web-Part 4)
Old 03-13-11, 12:18 PM   #14
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Default Re: Nuclear Accident In Japan

I know that this all sounds scary and articles putting out info about radioactive cesium detected near the site of the plant explosion brings out the anti-nuke crowd in force. The reality is that these are thermonuclear reactors using U235 fuel plates as I previously posted. In the worst case scenario of a complete primary containment breach, the release of radioactive contamination into the atmosphere will most likely be minimal, barring some really dumb move by Japan to try and "save" the plants. Radiation levels will likely be higher near the site but let's not get too excited by some press headlines. It also important to understand the difference between radioactivity and radiation.

Radioactive byproducts of fission such as cesium give off radiation and their potential for causing harm is greatest if ingested, Simply being exposed to some radioactive cesium at a distance is no different than being exposed to the sun or other daily forms of radiation we experience on a daily basis. If the Japanese do a good job of site containment and cleanup I see no reason for long term health risks to the community such as what happened at Chernobyl.

The key to getting these sites under control is to:

1) Get coolant flowing through these cores again if possible.

2) Get a neutron absorbing chemical pumped into the cores or

3) Get the coolant removed from the primary coolant loops, completely exposing the fuel plates and allowing the core to shutdown in the absence of a moderator.

I would try to flood the entire reactor compartment area with a boron compound chemical agent, perhaps even try to dump a load of hafnium based metal pellets on top and then vacate the primary coolant loops. I think it is a given that there is significant core damage so trying to limit overall plant damage in the hopes of a rebuild should be abandoned at this point. Keeping the fuel plates partially exposed will further promote fission and only build up more dangerous pressure inside the vessel and fuel plates. Removing the moderator completely from the core will certainly melt down the core plates but they will subsequently shut down the fission activity, dissipating the heat and ultimately the pressure.

There will be no China Syndrome type event by such a method as some may fear. Once the fuel plates are breached the U235 density will not be sufficient to keep a critical fission event sustained to make that happen, even if it somehow melted into the water table.

I have yet to really dive into all the press coverage of this event but I am still amazed at the fact that they had such a limited backup plan for what is truly the most critical design element of the reactor; to keep coolant flowing through the reactor core. I have seen nothing yet that talks about any system design element that would allow for emergency gravity flow of a neutron absorbing agent into the core, in the worst case scenario such as this (if the primary coolant loops or vessel have been breached).

All that I can imagine is that the quake damage was so severe that the primary coolant loops themselves (there should be a minimum of two and preferably four) were somehow damaged to a point that pumping coolant by any means became impossible. However looking at news images of the site I just don't see that kind of quake related catastrophic damage to the plant.

There is a serious design problem here IMHO, but what do I know?



Any injuries / fatalities are tragic but unfortunately it comes with the territory of producing energy. Sum up all the accidents and deaths that occur at coal/oil/gas fired power plants and refineries each year.

No simple answer if we want to keep the lights on and cars moving...
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Old 03-13-11, 02:14 PM   #15
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Default Re: Nuclear Accident In Japan

Agree all should remain clam... as there is not too much anyone can really do...

Think your correct... infrastructure for many, many systems must have been significanly damaged... surprised how much is still standing ...

Just another view on issues associated with this topic, which much be taken into account...

The Health Physics Society's position statement first adopted in January 1996, as revised in July 2010, states:[13]

In accordance with current knowledge of radiation health risks, the Health Physics Society recommends against quantitative estimation of health risks below an individual dose of 5 rem in one year or a lifetime dose of 10 rem above that received from natural sources. Doses from natural background radiation in the United States average about 0.3 rem per year. A dose of 5 rem will be accumulated in the first 17 years of life and about 25 rem in a lifetime of 80 years. Estimation of health risk associated with radiation doses that are of similar magnitude as those received from natural sources should be strictly qualitative and encompass a range of hypothetical health outcomes, including the possibility of no adverse health effects at such low levels.

And the races goes on... Juda... !!!
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Old 03-13-11, 02:59 PM   #16
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Default Re: Nuclear Accident In Japan

Quote:
Originally Posted by dusty
Obama can direct Susan Rice to have the UN create a resolution that all nuclear power plants will be dismantled within two years and the IAEA will enforce the resolution. That should take care of your concerns.
Gee. I didn't expect sarcasm. I like to reserve that for my personal use.

This thing is still playing out. But, regardless of the final outcome, which I fervently hope is best case, there are still two major issues with Nuclear power.

I mentioned the waste disposal issue. Folks have been playing around for years about the site in the California desert, with the continual concern about the potential for water contamination.

Then, there's the seeming best case scenario that finds the Japan at risk plants shut down with little or no harm to the environment, but unable to be rehabilitated.

Bottom line is that I have no magic recommendation for sourcing energy. Just have to wonder, however, using a risk/ benefit analysis, where nuclear stands in the choices. Seems to me that a catastrophic failure, combined with the other issues I mentioned, puts nuclear farther down the list. Especially in regions of the world where there is clear evidence of seismic events.

I'm guessing that whenever these Japanese plants were penciled out, a 9.0 temblor was not part of the equation, given that the facility has to be cost effective. And then, there's that "low-bidder" thingy.
Old 03-14-11, 05:43 PM   #17
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Default Re: 8.9 Quake, Tsunami & Nuclear Accident In Japan

looks like we get to see a whole new level of "radiation" ..... before I die...

and I thought it was only Toyota cars... can Seppuku be far off....
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Last edited by wessongroup; 03-14-11 at 06:11 PM. Reason: after thought
Old 03-14-11, 08:35 PM   #18
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Default Re: 8.9 Quake, Tsunami & Nuclear Accident In Japan

The more I read about what is going on over there the more I get the sense that the Japanese made a huge mistake in the first 48 hours by attempting to shut down the cores using methods that would minimize the overall damage to the plant (from what I have read) in hopes of minimizing overall economic losses.

If they were not able to get power to primary coolant pumps by any outside method in the first hours or if the primary coolant loop(s) were breached, seawater should have been pumped in as fast as they could get a mobile diesel generator onsite. The fact that they waited several days to start pumping seawater in will probably be seen as a major bad decision in retrospect.

I really am amazed at how poorly they were prepared for a catastrophic event. If the tsunami could take out diesel generator backup and the only option left was a couple of hours of batteries, they have some serious DC design issues.

I know for a fact that US based plants (where I have visited) are much better prepared for such situations to ensure core integrity and plant safety. Something tells me that nuclear plants around the world are reviewing their own backup plans as we speak...

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Old 03-14-11, 08:55 PM   #19
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Default Re: 8.9 Quake, Tsunami & Nuclear Accident In Japan

Before supposedly "semi-retiring" (hah) a few years ago, I was responsible for business operations in Latin America and Asia Pacific and had an office a few blocks from Tokyo Station.

I have been trading emails with some former associates, one of them a senior executive at Mitsubishi. He has contacts everywhere and has given me an update on what he has foiund out. It is of particular concern to him because he has a lot of family that live near the Fukushima plant. They came through the earthquake and tsunami fine, but were within the evacuation area.

First off, (and I hope BG chimes in here to take care of any misinformation) the media that are saying this is a potential Chernobyl are ill informed at best. The idiot Russians did not have any containment structure at all so when it went, it went all at once.

Worst case is that this might be a 3 Mile Island incident because they are very similar in design, with the Fukushima plant being a bit newer design. These have 2 containment structures like 3 Mile.

The latest designs use convection cooling which is supposed to continue to work regardless of any power or other issues. BG will certainly know a lot more here.

Oh, and Bajahowood, just so you know. In Japan most of the contractors that work on a project like a nuke plant belong to the same "Keiretsu", or business consortium. The winning bidder is usually the one most politically connected on that particular project and seldom the lowest bidder. The winning "Keiretsu" has their reputation (honor) on the line. In Japan this is more important than anything, including profits. I have a lot of confidence that the plants were built to the highest standards known at the time.

I do agree with the cost versus probability issue though. I also share your concerns about the waste, but the reality is that there are hundreds of nuclear plants around the world and the technology for building them safely has come a long way since "The China Syndrome". As BG will confirm, the US Navy has been using nucler reactors on ships since the 1950's and I don't recall a single incident or a single person being killed.

Interesting tidbit: Number of people killed in nuclear accidents last year-0
Number of people killed by power generating wind turbines in just the USA-44

I don't claim to be smart enough to know if we should have nuclear generating plants at all, but I do know one thing, if you shut them all down anytime in the next 20-30 years, which is how long it will take for a viable alternative.....buy a lot of candles.
Old 03-14-11, 09:22 PM   #20
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Default Re: 8.9 Quake, Tsunami & Nuclear Accident In Japan

Chernobyl used a breeder fuel type reactor that uses the more common form of uranium - U238, which will continue to fission even in the complete absence of water. Thermonuclear plants use a refined form of uranium - U235, which requires a moderator (water) which along with its coolant duties also slows neutrons down to a thermal level.

Neutrons (one of the byproducts of fission) streaming out from fission in the core are the same neutrons that will collide with other uranium atoms, making them instable and fission. In a U238 core, neutrons from fission can immediately collide and cause another fission event. In a U235 core, the neutrons must collide on average 5 to 7 times with large water molecules to slow down to thermal speed where they will "hang around" long enough in a U235 nucleus after collision to be able to cause another fission event.

Take all the water (coolant) out of a U238 core and it continues to fission. Take all the water (coolant / moderator) out of a U235 core and it will suffer some core damage from the heat but shutdown when all the neutrons radiate out as they are going too fast to cause another fission.

The real problem here is where the core remains partially covered with water (as at 3 mile island) where fission continues and pressure builds from overheating along with core damage.

As an interesting side note, more than 25 years after the Chernobyl event and in spite of the entire plant being encased in concrete, Chernobyl continues to fission away under all that cement, rock and rebar weight. It is slowly and methodically deteriorating the concrete encasement, requiring a "Plan B" that will need to be implemented, probably sometime in the next ten years.

A friend and former classmate is working as part of a multinational team trying to come up with that "Plan B"...
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