Yeah the explosion looks just like what happened at reactor #1. Walls and roof missing on reactor #3 now.

They're going to be just fine people. LGBR assured us of it.

I wish to address the concerns many of us have over the growing problems with the Japanese nuclear reactors. Japanese engineers have confirmed that hydrogen explosions have occurred and radiation has been detected outside of the reactors. I spoke with these engineers this morning, and they assured me that I have a very large penis.

:lol:

Damnit, I told them if they'd leave it alone it would take care of itself. :cool: suntan

Containment vessel undamaged. But the building looks more damaged than the #1 reactor building after it's explosion.

Looks like there are injuries.

That's ok, with all the radiation they'll grow their arms and legs back in no time.

Live Earthquakes Map

edit: AccuWeather.com - Weather News | Winds at Japan Power Plants Should Send Radiation out to Sea

http://vortex.accuweather.com/adc200...typpacwind.jpg

:chill: Nothing to see here folks.

TEPCO is holding a news conference:

Called ambulance for guy with a bruise but he didn't go to hospital.

7 people missing.

Water level of reactor core 1800mm? This is the value that was measured at 11:35 AM.

jomo any chance of a typhoon hitting japan??

Nah, although I wouldn't rule it out due to the ****ty luck they are having.

**** with this luck, a radioactive typhoon...

Vid of the explosion today:

http://www.youtube.com/watch?v=pIZKlaEZMLY

OH NO NEGLIGIBLE RADIATION!

****! ****!!!!!

you guys are ****ing worse than the yellow journalists we have as News Sources

My dream of wanting a house on the beach is no longer...

Looks fine to me.

copy/paste

What in the hell is going on here?

In the aftermath of the recent earthquake and tsunami in Japan, two nuclear power stations on the east coast of Japan have been experiencing problems. They are the Fukushima Daiichi ("daiichi" means "number one") and Fukushima Daini ("number two") sites, operated by the Tokyo Electric Power Company (or TEPCO). Site one has six reactors, and site two has four. The problematic reactors have been #1 and #3 at site one, which are the oldest of the ten.

In short, the earthquake combined with the tsunami have impaired the cooling systems at these reactors, which has made it difficult for TEPCO to shut them down completely. Reactor #1 is now considered safe after crew flooded the reactor with sea water. Reactor #3 is undergoing this process as this is being written (6:00PM CST/11:00PM GST on March 13th).

Can this cause a nuclear explosion?

No. It is physically impossible for a nuclear power station to explode like a nuclear weapon.

Nuclear bombs work by causing a supercritical fission reaction in a very small space in an unbelievably small amount of time. They do this by using precisely-designed explosive charges to combine two subcritical masses of nuclear material so quickly that they bypass the critical stage and go directly to supercritical, and with enough force that the resulting supercritical mass cannot melt or blow itself apart before all of the material is fissioned.

Current nuclear power plants are designed around subcritical masses of radioactive material, which are manipulated into achieving sustained fission through the use of neutron moderators. The heat from this fission is used to convert water to steam, which drives electric generator turbines. (This is a drastic simplification.) They are not capable of achieving supercritical levels; the nuclear fuel would melt before this could occur, and a supercritical reaction is required for an explosion to occur.

Making a nuclear bomb is very difficult, and it is completely impossible for a nuclear reactor to accidentally become a bomb. Secondary systems, like cooling or turbines, can explode due to pressure and stress problems, but these are not nuclear explosions.

Is this a meltdown?

Technically, yes, but not in the way that most people think.

The term "meltdown" is not used within the nuclear industry, because it is insufficiently specific. The popular image of a meltdown is when a nuclear reactor's fuel core goes out of control and melts its way out of the containment facility. This has not happened and is unlikely to happen.

What has happened in reactor #1 and #3 is a "partial fuel melt". This means that the fuel core has suffered damage from heat but is still largely intact. No fuel has escaped containment.

How did this happen? Aren't there safety systems?

When the earthquakes in Japan occurred on March 11th, all ten reactor cores "scrammed", which means that their control rods were inserted automatically. This shut down the active fission process, and the cores have remained shut down since then.

The problem is that even a scrammed reactor core generates "decay heat", which requires cooling. When the tsunami arrived shortly after the earthquake, it damaged the external power generators that the sites used to power their cooling systems. This meant that while the cores were shut down, they were still boiling off the water used as coolant.

This caused two further problems. First, the steam caused pressure to build up within the containment vessel. Second, once the water level subsided, parts of the fuel rods were exposed to air, causing the heat to build up more quickly, leading to core damage from the heat.

What are they doing about it?

From the very beginning, TEPCO has had the option to flood the reactor chambers with sea water, which would end the problems immediately. Unfortunately, this also destroys the reactors permanently. Doing so would not only cost TEPCO (and Japanese taxpayers) billions of dollars, but it would make that reactor unavailable for generating electricity during a nationwide disaster. The sea water method is a "last resort" in this sense, but it has always been an option.

To avoid this, TEPCO first took steps to bring the cooling systems back online and to reduce the pressure on the inside of the containment vessel. This involved bringing in external portable generators, repairing damaged systems, and venting steam and gases from inside the containment vessel. These methods worked for reactor #2 at site one; reactors four through six were shut down before for inspection before the earthquake hit.

In the end, TEPCO decided to avoid further risk and flooded reactor #1 with sea water. It is now considered safely under control. Reactor #3 is undergoing this process.

Is a "China Syndrome" meltdown possible?

No, any fuel melt situation at Fukushima will be limited, because the fuel is physically incapable of having a runaway fission reaction. This is due to their light water reactor design.

In a light water reactor, water is used as both a coolant for the fuel core and as a "neutron moderator". What a neutron moderator does is very technical (you can watch a lecture which includes this information here), but in short, when the neutron moderator is removed, what happens to the fuel core depends on its design.

An LWR has a design with a "negative void coefficient". This means that if the neutron moderator is removed, the fission reactor will slow and eventually stop. Some other reactor designs (such as the one at Chernobyl) have a "positive void coefficient", which means that if the moderator is removed, the fission reaction speeds up and becomes self-sustaning.

An LWR design limits the damage caused by a meltdown, because if all of the coolant is boiled away, the fission reaction will not keep going, because the coolant is also the moderator. The core will then only generate decay heat, which while dangerous and strong enough to melt the core, is not nearly as dangerous as an active fission reaction.

The containment vessel at Fukushima should be strong enough to resist breaching even during a decay heat meltdown. The amount of energy that could be produced by decay heat is easily calculated, and it is possible to design a container that will resist it. If it is not, and the core melts its way through the bottom of the vessel, it will end up in a large concrete barrier below the reactor. It is nearly impossible that a fuel melt caused by decay heat would penetrate this barrier. A containment vessel failure like this would result in a massive cleanup job but no leakage of nuclear material into the outside environment.

This is all moot, however, as flooding the reactor with sea water will prevent a fuel melt from progressing. TEPCO has already done this to reactor #1, and is in the process of doing it to #3. If any of the other reactors begin misbehaving, the sea water option will be available for those as well.

What was this about an explosion?

One of the byproducts of reactors like the ones at Fukushima is hydrogen. Normally this gas is vented and burned slowly. Due to the nature of the accident, the vented hydrogen gas was not properly burned as it was released. This led to a build up of hydrogen gas inside the reactor #1 building, but outside the containment vessel.

This gas ignited, causing the top of the largely cosmetic external shell to be blown off. This shell was made of sheet metal on a steel frame and did not require a great deal of force to be destroyed. The reactor itself was not damaged in this explosion, and there were only four minor injuries. This was a conventional chemical reaction and not a nuclear explosion.
http://i.imgur.com/rCSr2.jpg
You see what happened in this photo. Note that other than losing the sheet metal covering on the top, the reactor building is intact. No containment breach has occurred.



At about 2:30AM GMT on March 14th, a similar explosion occurred at the reactor #3 building. This explosion was not unexpected, as TEPCO had warned that one might occur. The damage is still being assessed but it has been announced that the containment vessel was not breached.

Is there radiation leakage?

The radiation levels outside the plant are higher than usual due to the release of radioactive steam. These levels will go down and return to their normal levels, as no fuel has escaped containment.

Here is a chart showing the effects of various radiation poisoning levels. For perspective, note that this chart starts at 1 Gy, equivalent to 1 Sv; the radiation outside the problematic Fukushima reactors is being measured in micro-Svs per hour. The highest reported levels outside the Fukushima reactors has been around 1000 to 1500 micro-Svs per hour. This means that one would have to stay in this area for four to six weeks, 24 hours a day, without protection in order to experience the lowest level of radiation poisoning, which while unpleasant is not normally fatal. And this level will not stay where it is.

Also note the chart of normal radiation exposure levels from things like medical x-rays and airline flights.

There have also been very minor releases of radioactive reactor byproducts like cesium along with the steam. This material is less radioactive than the typical output of coal power plants. It is significant mainly as an indicator of the state of the reactor core.

I read that there's a plume of radioactive material heading across the Pacific.

In its current state, the steam blowing east from Japan across the pacific is less dangerous than living in Denver for a year. If it makes it across the ocean, it will be almost undetectable by the time it arrives.

What's this about fuel rods being exposed to the air?

When the coolant levels inside the reactor get low enough, the tops of the fuel rods will be exposed to the air inside the containment vessel. They have not been exposed to the external atmosphere and the containment vessels are all intact.

Can this end up like Chernobyl?

No, it cannot. for several reasons.

* Chernobyl was designed with a positive void coefficient. This means that when the neutron moderator was removed, the reaction got stronger. The Fukushima reactors have a negative void coefficient, which means that if you remove the neutron moderator, the reaction slows and eventually stops.

* Chernobyl's core was built on top of a tank of water. This was meant to cool the core if it melted through the containment vessel. Instead, it caused a tremendous steam explosion which tore the facility apart. The Fukushima reactors do not have this and will therefore not explode like that, even if the core melts through the containment vessel.

* Chernobyl used graphite as a neutron moderator. Graphite is flammable, and when the reactor exploded, the radioactive graphite burned and ended up in the atmosphere. The Fukushima reactors use water as a neutron moderator, which is obviously not flammable.


The news said this was the worst nuclear power accident since Chernobyl, though.

It's the only nuclear power plant accident of its type since Chernobyl. It's easy to be the worst in a sample size of one.

Is this like Three Mile Island?

There are similarities. The final effect on the world is likely to be similar: no deaths, minimal external contamination, and a tremendous PR disaster for the nuclear industry due to bad reporting by the media.

How can I keep up with developments?

The western media has been very bad about reporting this event, due to a combination of sensationalist reporting, ignorance, and the use of inexact or unexplained terminology.

One of the safe sources of information is the TEPCO site, which has been posting press releases on a regular basis. Unfortunately, this site is often unresponsive due to the immense traffic it is receiving.

The important thing to remember is that most of the "experts" appearing on the news are engaging in speculation. Very few of them are restricting themselves to what they can be sure about, and those that are have often been misrepresented.

Great wall of text captain obvious

he's basically calling you a moron Golbez

because you're part of the sensationalist problem

OH **** RADIATION ISLEAKING OUT AND W"ERE ALL ZOMBIE ALIEN MUTANTS

you heard it here first from GOLBEZ!!!!!

Just like the deepwater horizon.

No leak here!
Oh, well there may be a leak, but it's only 300 barrels per day!
Maybe we shortchanged it a bit. 500 barrels per day!
New estimates show 1,200 barrels leaking per day!
...3,000...10,000....50,0 00...

No way it could be worse than reported, right?

Thanks Walking, that was a good article.

I don't know if this has been posted before, but it shows before/after arial photos of the damage.

ABC News - Japan Earthquake: before and after

AWWWWWWWWWWWW!!!!!!!!!!!! !!!!

Nuclear Energy Regulation doesn't work like Oil Drilling Regulation.

The more you knew.

Please, elaborate.

As we all know, governments are very forthcoming when reporting on disasters and always promptly report worst case scenarios.

At least I know which buildings to buy in those areas.

yeah japan and the united states are so similar in politics, culture, and government that oil drilling regulations in the united states have to be identical to nuclear regulations propagated by nuclear energy treaties on a world level that are then run through individualized national governments for rules that require a local touch.

keen observations

are you jomo?

Japan's nuclear power operator has checkered past | Reuters

*In 2002, the president of the country's largest power utility was forced to resign along with four other senior executives, taking responsibility for suspected falsification of nuclear plant safety records.

*In late 2006, the government ordered TEPCO to check past data after it reported that it had found falsification of coolant water temperatures at its Fukushima Daiichi plant in 1985 and 1988, and that the tweaked data was used in mandatory inspections at the plant, which were completed in October 2005.

*And in 2007, TEPCO reported that it had found more past data falsifications, though this time it did not have to close any of its plants.

yeah thanks for linking me incidents that are 4 to 8 years old to try and establish that at this very moment, big scary corporate boogey men from japan are going to contaminate the world with radiation

this is all probably wrong

but it feels so right

DON'T WORRY! NOTHING TO PANIC ABOUT. NO RADIOACTIVE MATERIALS HAVE BEEN RELEASED FROM CONTAINMENT!

http://www.nytimes.com/2011/03/14/wo...lume.html?_r=2

:lol:

how? the writer explains that basically nobody in the western media has any primary sources from which to draw conclusions, indicating that almost everyone the news calls in as "experts" are merely speculating on information.

it also explains how technology/standards/engineering has improved/changed since chernobyl in regards to safety and mitigation of runaway fission.

++ on reading comprehension, though. try again.

no **** ... they already reported radiation leaks ... and they stated it is going to be pretty bad

please tell me more about how the gubmet is hiding information about the radiation leak... the truth is out der

Zero chance of this happening right now... simply put the surface temperature of the water in the northern hemisphere is too cold to sustain a tropical revolving storm (aka typhoon, hurricane, cyclone etc).

Thanks, good post.

Gow et al, I think the reasons some of us were concerned about this, despite your insistence that the containment vessel was completely reliable include:
1) People can make mistakes, even groups of particularly clever people, like designers of containment vessels.

2) Organizations don't always fully disclose scary information. Several sources described the information flow from the folks running the plant as sporadic, or in some cases inconsistent.

3) When we hear that the containment vessel is completely reliable, and then hear that radiation levels are rising outside, we tend to think that these things conflict. If it had been explained in advance that they were going to be venting X type of material, which would likely raise nearby radiation levels to Y amount, and that this is still safe because of yada yada, then I think there would be less concern.

4) Buildings don't normally blow up. When they do, we tend to think that things are not going according to plan, and that other things (like the integrity of the containment vessel) might also not be behaving as expected.

Hey Walking_Man, can I get a link to the source on that? I'd like to send a few morons some real information.

Lucky bus at about 1:05

http://www.youtube.com/watch?v=EZMqVTPhHzI