Japanese Quake and tsunami

[rasorinc]

they are using fire engines there to spray down now.

[SamSam]

The problem might also be that they had a tsunami that may have wrecked all infrastructure, including concrete plants or roads and bridges needed to get materials to the area. It might also be a problem that everyone within 20 kilometers are under mandatory evacuation orders. It might also be that burying is a truly last ditch, no return policy with huge consequences.

[kroberts]

Originally Posted by Ad Hoc

Paul

My house is!!...it is designed to a greater quake than the "great Hanshin Earthquake" as it is called here. The big one that hit Kobe (where I live) in 1996, that was a 7.4 if i recall.

I have treid to find a link showing you the spec's..but they are all in Japanese. But it is a house built by Asahi Kasei Homes.

And yes, it's bloody expensive...but they all are here....never sure why, since they are all made this way...but that is another story!

So your house can withstand the quake. Can it withstand the 60 mph wall of water filled with buildings, cars, boats and drowning people?

I don't live in an area where a tsunami is even theoretically possible. I don't live in an area where a hurricane is even theoretically possible. But I have talked to somebody who lost his hurricane-proof house to Katrina. He said his house was built to withstand 100+ mph winds no problem. What it couldn't withstand was a 100 mph trash dumpster coming through the upstairs wall.

One thing we get near me is floods. Cities typically build to a 100-year standard, sometimes a 200 year standard. Only some of those towns haven't been there 100 years, so they're guessing. So what that means is they try to figure out the highest water level that area has seen in the past however-many-years, and then they build the dike that high.

The anticipation is that they won't have to worry about floods for that many years, but what it REALLY means is that statistically speaking they will probably get a breach in half that many years. Also statistically speaking, if I made my 100 year dike, a month after I finish I could get the 1000 year flood. That's just how it happens sometimes.

Now, taking that further, it seems to me that Japan built this reactor to withstand more than had ever happened on that site in their recorded history. It seems to me that Japan's recorded history is probably a bit longer than the USA's recorded history, and the thing that took it down was more than they had ever gotten before. I don't think we can fault them for the way they built the reactor.

[Fanie]

Our TV announced a restriction on stuff imported from Japan due to the possibility of radiotion contamination. Pathetic as it seems you can do nothing about how little people know about radioactivity. As if the whole of Japan got radiated and the effect is permanent.

[SamSam]

Originally Posted by kroberts

Can it withstand the 60 mph wall of water filled with buildings, cars, boats and drowning people?....I don't think we can fault them for the way they built the reactor.

I wonder. Tsunami is a Japanese word, after all, those and earthquakes are not unknown to them. It's possible they may yet be faulted for the way they built the reactor. Maybe they can be faulted for the design of it. Maybe they can be faulted for the location of it. Maybe they can be faulted for the way they built the emergency backup systems for it. Maybe they can be faulted for their management of the reactor and the way they maintained it.

They built it and now it's causing a huge problem. If they are not to blame that it's now a smoking, radioactive heap, maybe they are to blame that they built it at all in the first place.

[Boston]

while I agree that the environmental concerns are the most important and now that you have a smoking pile of ruins its boiling down to how to mitigate the damage best. But I think the primary reason for nuclear is to enrich fuel which also just happens to be the stuff needed to make a bomb out of. Anyone feel like explaining the different types of fuel cause I'm not so clear on whats what that powers these reactors. Thanks. I know at least in this country the DOD ( department of defense, formerly known as the department of war ) has got its fingers in anything nuclear so its pretty clear that at least some of the responsibility lies at the feet of the gov. who's DOD was in charge, to some degree or another. The decision to build on reclaimed land and so near the sea is one I"m sure that will be reviewed till eternity.

[Submarine Tom]

Interesting that some feel blame has to be laid.

What a shame the plant wasn't properly designed, especially with all the knowledge available here on this thread. Where were you when we needed you? Imagine if you had been involved in the immaculate design and it somehow failed, I wonder if others would then blame you! Why does it feel so good for some to blame others?

-Tom

[rasorinc]

General Electric designed and I think built the reactor vessels.

[hoytedow]

Originally Posted by Submarine Tom

Interesting that some feel blame has to be laid.

What a shame the plant wasn't properly designed, especially with all the knowledge available here on this thread. Where were you when we needed you? Imagine if you had been involved in the immaculate design and it somehow failed, I wonder if others would then blame you! Why does it feel so good for some to blame others?

-Tom

I could not agree more. Besides GE designed it. GE is all green now for political reasons. Go blame them.

[SamSam]

Why shouldn't blame be laid? There is a big problem causing harm to who knows how many people. An "Act of God" caused the earthquake, an "Act of God" caused the tsunami, a human failure of some sort caused the plant to be in the condition it is.

It is a shame the plant wasn't properly designed. Whatever is responsible, to blame, for it's present state of dis-repair, should be looked at so it can be dealt with when the next nuke plant is built somewhere, or the present ones can be strengthened. Considering the environmental mess failure can cause, if it's not economically feasible to build one that can withstand the forces of nature, it seems it shouldn't be built, yet it was and here we are.

I've worked in one of those same reactors, GE Mark 1s, 4 times. Inside and outside the torus, inside and outside the drywell, up on the fueling floor and outside at the cooling pumps. I've seen how they're built and I've talked to people that built them, way back before drug testing. They're roughly 40 years old, past their prime, it's debatable whether they will be re-licensed when their time is up, it's debatable whether it's economically feasible to pump in millions for repair.

There might be one not far from where you live, but don't worry about it, no one's to blame if anything happens.

[kroberts]

@SamSam,

There's a huge difference between post-failure examination and assigning blame.

Name even one thing you have accomplished in your life that cannot be broken. Are you saying we should blame you if anything you ever did comes apart?

I find that point of view extremely fatalistic. Why should anyone do anything at all in a world like that? We should all be chasing after dinner, beat it on the head with a rock a few times, and then eat it raw while it's still quivering.

Japan's punishment for the failed reactor is inherent in the failure of the reactor. It's possible some gross negligence will be found, and if that sort of thing caused huge additional harm then I can definitely see going after whoever did it, but I definitely do not think people should crawl under a rock and hide for the rest of their lives.

[cthippo]

Originally Posted by Boston

while I agree that the environmental concerns are the most important and now that you have a smoking pile of ruins its boiling down to how to mitigate the damage best. But I think the primary reason for nuclear is to enrich fuel which also just happens to be the stuff needed to make a bomb out of. Anyone feel like explaining the different types of fuel cause I'm not so clear on whats what that powers these reactors. Thanks.

Sure.

The key property of a nuclear fuel is the ability to sustain a nuclear chain reactions. In order for that to happen, when the nucleus is hit by a neutron it must split, or fission, and release at least one neutron in the process. Since not all neutrons will find another nucleus to hit, it really needs to release more than one neutron to keep the reaction going. Only a handful of elements and isotopes of these elements have this property, specifically Uranium 233, 235, Plutonium 239 and 240, and Thorium. U233 is produced from Thorium, but no one has ever been able to get a Thorium fueled reactor to work (though India is trying), so we'll discount those for the moment. Plutonium does not naturally exist on Earth, but is still a viable nuclear fuel, but we'll come back to that in a minute.

Natural uranium when it comes out of the ground consists of 99.3% U238 and about .7% U235 with a tiny amount of U234 in there as well. U235 is capable of sustaining a nuclear chain reaction, but U238 is not. It is possible to build a nuclear reactor that "burns" natural uranium and some commercial reactors of this type (notably the CANDU) have been built. The challenge with natural uranium reactors is that they produce relatively little power for their size and require expensive heavy water for the moderator. Another design using natural uranium is optimized for plutonium production and uses graphite as a moderator and is frequently gas cooled. Examples of this design are the Windscale piles in the UK and Yongbong in North Korea.

Most power reactors use uranium which has been enriched, a process by which the U235 content has been increased relative to the amount of U238. The by product of this process is depleted uranium which contains less than natural amounts of U235. Enriching uranium is an extremely difficult and expensive process requiring massive industrial facilities. Commercial reactor fuel is typically enriched to 3-5% U235, though some research reactors use fuel enriched up to around 30% and naval reactors, which require extremely high energy densities, can use fuel up to 90% enrichment. By contrast, weapons grade uranium is typically enriched to at least 85% U235.

When nuclear fuel is produced it is "canned" into fuel rods or assemblies of various shapes depending on the type of reactor it's going to be used in. Uranuim is an Alpha particle emitter, and alpha particles can be stopped by something as thin as a sheet of paper, so the cladding serves to stop the radiation of the unused fuel. When the fuel is in the reactor the uranium atoms split, releasing energy, but the remnants of those atoms (called daughter particles) are themselves more radioactive than the parent uranium. The cladding of the fuel elements keeps those reaction products safely contained. The raw fuel that goes into the reactor is very safe to handle, but the spent fuel that comes out is extremely radioactive and dangerous. The spent fuel is placed in pools to allow the residual radioactivity to die off so that it can be safely handled (or stored forever since no one can agree on a permanent way to dispose of it).

The other usable nuclear fuel is plutonium which does not naturally exist on Earth, but is a byproduct of "burning" uranium in reactors. During the cold war fuel was irradiated in specially designed reactors (Hanford in the US, Windscale in the UK) to produce plutonium. Plutonium is present in all spent reactor fuel, but these reactors were designed in such a way as to maximize it's production. once the fuel was removed from the reactor it was allowed to "cool" for a period of usually 90 days during which the short lived and thus highly radioactive daughter particles decayed. The fuel was then dissolved in nitric acid and the plutonium was precipitated out of the solution and purified in a process known as Plutonium / URanium EXtraction or PUREX. The finished plutonium could then be used either to fashion nuclear weapons or made into fuel for reactors. In the post cold war era the entire industrial base for plutonium production and finishing in the United States has been dismantled and removed, leaving an environmental mess that will go on for decades. Plutonium reactors have a number of advantages over uranium fueled ones, but proliferation concerns have put them somewhat out of favor in the last couple of decades. Currently the economics of the fuel cycle argue against commercial reprocessing and I'm not sure if any country is reprocessing commercial nuclear fuel.

A special type of plutonium reactor known as a breeder produces more fuel than it consumes. This is accomplished by irradiating depleted uranium placed around the outside of the reactor and then re-processing it to remove the created plutonium. Many countries have experimented with breeder reactors but currently only Japan and Russia have commercial breeder reactors in service. The breeder concept is attractive to nations such as Japan and India which have limited Uranium reserves because once the initial charge is loaded, they only require cheap, non-fissionable U238 fuel.

EDIT: To clear up a question I missed from Boston, I don't believe that commercial fuel has been re-processed into plutonium for weapons, at least not in the west. The Russian RBMKs (of which Chernobyl was one) were designed to produce plutonium as a secondary goal to producing electricity.

Someone mentioned the RBMKs as a distinct reactor type. They are in fact boiling water reactors, but of a relatively uncommon design due to the secondary goal of plutonium production. Most BWRs are water cooled and water moderated meaning that the water both transfers the heat out of the reactor and also serves to slow down, or moderate, the neutrons flying around inside the fuel. Slow neutrons work better than fast ones for power production and so most reactors use some sort of moderator in their design. The RBMK design instead uses graphite as a moderator because it absorbs fewer neutrons than water does which increases plutonium production. After the explosion at Chernobyl the burning graphite in the core of the reactor caused the accident to be worse than it would have been otherwise. Another design element which contributed to the severity of the accident at Chernobyl was the lack of a primary containment structure to mitigate the release of radioactive particles.

[Ad Hoc]

Originally Posted by kroberts

So your house can withstand the quake. Can it withstand the 60 mph wall of water filled with buildings, cars, boats and drowning people?

Not sure how much coverage you get where you live, but the video images you may have seen, taken by people with the cameras etc, they took them on buildings which were made of steel. The foundations are made from steel reinforced concrete (proven to be the most earthquake resistance structure by many institutions worldwide), and the frames of the buildings are steel. All those buildings survived. There is one telling BBC report by a journalist of a waste land with a single house remaining, this was built as described above, where a mother rushed to give her children to their cousins, in their steel made houses, just as she was washed away...the house remained intact.

The houses you see washed away were built from wood. Most houses in Japan are built from wood; but that is another story.

My house is built with steel reinforced concrete and steel frame. So, to answer your question, yes, from the evidence shown, it probably would. Would yours?

Originally Posted by kroberts

It seems to me that Japan's recorded history is probably a bit longer than the USA's recorded history,.....

Japan’s recorded history is not a “bit more”, it is significantly more. America as we know it today has a recorded history at best of some 400 years at best, and that is being generous. Japan has a recorded history, going back over 2 thousand years. I used to live near the oldest wooden structure in the world, it is 1500 years old. It has a very detailed account of who built it, why, with what money, etc etc…all perfectly recorded and preserved.

The tsunami that hit has is now shown to be a one in a 1000 year event. The last that occurred of a similar magnitude that hit Japan was in 869. See plenty of records.

http://www.bbc.co.uk/news/science-environment-12740649

Originally Posted by kroberts

There's a huge difference between post-failure examination and assigning blame.

Agreed.

Since the principal “cause” was simply triggered by the loss of the generator, from the tsunami, to provide power for the cooling pumps. The fact the rest of the structure withstood a major quake, (the largest ever recorded in Japan) and more than it had been designed too…seems to be over looked by many. This fact must be applauded.

[ancient kayaker]

Originally Posted by Submarine Tom

... What a shame the plant wasn't properly designed ... -Tom

True. There have been 7 earthquakes of magnitude 8 or more in Japan since 1891, so a M8 ‘quake is hardly a 100 year event, closer to a once in a decade event. While a M9 ‘quake is unprecedented since measurements have been kept, the Alaska 'quake was magnitude 9.2 and happened in 1964 shortly before construction started on the Fukushima plant.

However it was the tsunami and its aftermath that did the worst. Tsunamis are not hourly events even in Japan, unlike 'quakes, and last week’s tsunami has been described as a once-in-1000-years event which is hard to predict. But tsunamis and their potential for massive destruction were known in Greek times. Even with the limited knowledge of the day it was constructed, someone should surely have questioned the wisdom of siting the plant so close to the coast; there are large lakes in the area that could have supplied the cooling water.

At the very least the backup generation facilities should have been designed to the same standard as the other structures.

[ancient kayaker]

Originally Posted by kroberts

@SamSam,

There's a huge difference between post-failure examination and assigning blame ...

1) the folk on this forum are entitled to express an opinion
2) like an aircraft crash, a post-failure examination is mandatory after this event
3) it would be nice to think that, like aircraft, nuclear facilities will be safer in the future but ...