When the wind changes, what happens then?
The Japanese government has declared an emergency at a second Japanese nuclear plant: Fukushima No. 2, seven miles away from Fukushima No. 1, which lost cooling after Friday's devastating megaquake in northeastern Japan. Japan's Kyodo News reports that on Saturday morning, Tokyo Electric Power Company (TEPCO) released news …
When the wind changes, what happens then?
that's why they talk about a *radius*
is this a tech forum ??
"safety can be assured"
Ah, I doubt if I'm the only one who reads that as 'We're fucked'.
If the problem is caused by a lack of power getting to the coolant systems, then presumably the relief valve 'door opening' mechanism is also without power...
...id hate to be the one that has to manually open the valve 'doors' / gate / shutters / lid / zip / whatever it is!
RayBan's and sock-barometer on stand by.
"notified the industry ministry that the failsafe system at the No. 2 plant stopped functioning .."
clearly not FAIL safe
the systems acted as they should have, shutting down the normal nuclear reaction, by inserting the control rods fully, which results in the fuel producing about 95% less heat .. but does stop the production of electricity from the plant
the trouble is that the 5% heat produced now needs to be drawn off by water flush, and the electrical power from the outside is cut off, so those water pumps can't run ..
They should have had a few large diesel generators available to run the water pumps and other electrical required, however it was not anticipated that the electricity from outside sources would be unavailable
there is a serious possibility of a core meltdowns
that they did have diesel generators but these failed after (?) hours.
Plant no. 1 had diesel backup, but that generator (or generators) was wash away by the tsunami. Given that plant no. 2 is "only" seven miles away, it is possible they planned to use plant no. 1's backup generator(s), or that the plant had its own which was likewise damaged or destroyed.
They worked for an hour before stopping working due to being damaged by the tsunami.
They had also batteries, but these last only eight hours.
They will probably release the pressure into the atmosphere before a meltdown can happen. This would however release radiation.
Good idea to have diesel generators on hand.
According to various other sources online, that's exactly what they have. Unfortunately, the diesels in question survived the earthquake, but were damaged by tsunami floodwaters.
In addition to the diesels, it sounds like they have battery back up (not sure if we're talking large-scale UPS or something like small scale DC systems) for the basic control systems (I assume that includes opening relief valves).
IIRC, nuke plants are not usually "black start", so they will require external power to start up.
I'm not a nuke physicist/technician/etc, but I'd imagine that the pumps required to circulate coolling water in a multi MW reactor would be rather large. Pulling a 10kw Honda generator out of the toolshed isn't going to cut it.
They also referenced a final emergency water cooling system, to be used as a last resort. Sounds like that's the "hit the big red button and you trash the plant, but it won't go critical" option. The blowing off of pressure is the "buy some time so we can restart this thing" option.
... only that they were unusable because they too got damaged.
It'd be fairly silly to suppose that there would't've been gensets, simply relying on the grid to keep a reactor safe. No backup gensets for a system that requires power to remain safe? I would consider that criminal. In fact the power that's left to run the cooling systems comes from batteries, with a capacity of some eight hours. Trouble is, restarting the reactors (even just for powering the cooling systems) won't be possible until after a day or two.
The first plant has diesel generators but they are not working. The news didn't say why. I should think that this plant would be the same.
Is it me or, despite the number of failsafes, generators etc, is it just not a very smart idea to use nuclear power generation in an area that suffers from massive earthquakes and subsequent tsunamis? It is, after all, quite a dangerous game at the best of times.
Sod that....have you seen the price of diesel these day??
No shock there... I've seen it myself at GEC Marconi in the late 80s. Nobody bothers looking after the backup generators properly, assuming that even if they have been ignored for 5 years that they will work for the few days they may be required for...
Unfortunately it doesn't work like that...
My understanding of the word failsafe is it means it fails in a safe way, not that it's safe from failure (ie can't fail).
From my reading the initial failure did happen safely, but subsequent failures didnt have a failsafe...
if they are finding caesium and iodine outside the plant these elements are only released if the core has been exposed to the atmosphere and the rods have ruptured.
they have a history of not quite telling the truth where incidents are concerned.
i an glad we have no reactors of this kind in our country they were always thought of as a liability but they were cheaper at the time than the ones we use.
As has been said its not a fail safe if the heat cant be removed from the core.
They had diesels, but those were drowned by tsunami. They should've thought of that though...
I'll get my hazmat suit, thanks
I've seen several installations over the years where the emergency generators have been located in the basement of the buildings ... often below ground. Mostly this is done for convenience since a decent, building or hospital sized, generator is LARGE - you also need to fuel them during a prolonged power outage and they make a lot of noise.
We had a large hospital locally that announced that they were just fine and running on emergency power after a recent hurricane - only to close about 6 hours later when they ran out of fuel for the generators.
The tendency is to make backup plans that fulfill the need to have a backup plan on record that functions during a "test" - in reality there are very few places that are prepared for a real disaster.
... should they have thought about? One of the biggest earthquakes ever measured happened in a place and way that led to an unprecedented tsunami which went further inland (and therefore higher up) than anything that could reasonably have been planned for.
There is the precautionary principle, then there is the insane level of not doing anything "just in case". Shit happens - live with it.
The corollary to that is that an occasional meltdown is acceptable, it just has to happen under a big enough tsunami and quake mix. I don't think so.
But then I've been saying for a while that the feature I most want in this sort of thing is that it fails in a safe way, like, oh, it doesn't need power to cool down. Design the thing such that you can just turn it off and it's off. That's not at all limited to nuclear but since that does tend to go boom most spectacularly it's also most important there.
Though I'll grant that the problem with this particular plant may also stem from it being an old design and newer designs might do better, or that say a stand-by airlift capacity of a couple MW in gensets might help, even though they still need power to cool down. I'd still vastly prefer they didn't.
Honestly, if all reasonable efforts turn out to not have been good enough then we're still stuck with a meltdown, so they were not enough and that's all there is to it.
After reading around a bit, though, it appears that even if the reactor core melts it will still be contained safely. That is, we won't get an actual Chernobyl-or-worse meltdown, just a melty core safely contained in its concrete-and-steel bottle. If that holds up then, yes, kudos for solid engineering as the /GAU/ appears to've been 8.2 and not 8.8^W8.9^W9.0. Maybe a bit sloppy about the gensets but, well, indeed, shit happens. I still wouldn't call an actual meltdown acceptable in any way or form, but it appears that's not going to come to pass. Which is just as well.
Huge crack opens up in the sea floor off Japan... and then the wind "safely" blows the radioactive gases ... yes, you guessed it... out to sea. Now all we need is a darkened freighter/research vessel to get things rolling...
Oh yeah, old movie plots in real life!
Since that mountain spar town in Iran (Ramsar, Mazandaran) has 200 times average background radiation and people are fine there, can anyone give an indication of how much radiation this process might vent relative to normal background radiation level extremes (low and high) and how it's likely to disperse?
From the major news outlets no one seems willing to discuss the finer points of radiation in any scientific way.
Interesting discussion of the "radiation risks" from a working nuclear plant. Basically the rules are so tight its more or the less safest place to be. Having the drains from a hospital going past your house being one of the most dangerous places to be.
Obviously its different once "stuff gets out", but this might serve as a handy reference.
(Paris - since even she knows the importance of "containment").
basically, unless the fuel rods have broken, the radiation will be negligible and disappear in seconds. If the fuel rods have broken, the radiation will be low to negligible but last longer
of course nobody will tell you this on the news, they will just say "radiation - we're dooomed, doooomed I tell you!"
That areas of the world that have high levels of NATURAL raditon have lower levels of birth defects and cancer! It was a few years ago when I read the study, and who knows how well the sample data was vetted.
If the population there has a high tolerance then it's probably going to be no biggie, it all depends on how bad this gets tbh, releasing radition will be the better of the two ills if it comes to that.
>>>> From the major news outlets no one seems willing to discuss the finer points of radiation in any scientific way.
Since when have the major news outlets ever discussed the finer points of anything? They're too far up their own arses and puffed up with self-importance to do any proper reporting.
In a few days they'll move on from Japan to "report" breaking news and rolling bollocks about the next major disaster: Britney loses an ear-ring, Jordan shags/does not shag washed-up footballer/pop star/actor, trendy shiny thing becomes uncool, megacorp drops old logo, etc.
Paris icon because she's got lots of direct experience of in-depth probing.
They're superstitious Earth-worshipping Greenies and don't understand science. These people think like small children. If they hear the word "radiation" they think "death ray". Society will go backwards unless we have better technology
I'd rather take my risks with a 40 year old reactor than bring my family up in a low-carbon yurt in winter.
The name of the location and the reaction you get if you visit the place.
How much of the troubles at the Japanese power plants is due to not following the safe route of shutting the thing down, instead of trying to save money avoiding having to restart the plants later.
I truly hope all of this doesn't end in tears.
But until well and truly cooled it still needs power to keep the coolant (water) going. Then wait for the thing to settle so that it might be restarted. The reason it can't be restarted right away is called "Xenon poisoning", I believe. The difference appears to be on the order of one to two days, well more than the eight hours the batteries last.
So they have 1) a reactor that no longer produces power but still needs cooling and therefore power to run the cooling, 2) a grid failure so no power from there, 3) (for not very clearly explained reasons) unusable gensets so no power from there either, and 4) eight hours of battery time to run the cooling and after that the coolant (water) will stop to circulate and start to boil off.
They might conceivably have been better off not shutting down the plant, or not as the case may be, but it's a bit late for that now.
I wonder if it wouldn't've been possible to drive a couple of fire trucks down there and just pump water in, but probably not.
Loosing *all* cooling water pump power while all your reactors are shut down.
Where on the planet could such a ridiculously improbable even take place?
*Mine will have a copy of John Howlett's "Maximum credible accident" in it.
BTW If I were going for the nuclear option today I'd go molten flouride Thorium hands down.
You are the manager of nuclear plants 1,2,3,4,5
There is an earthquake/Tsuanmi/natural disaster. Some of the generating plants are damaged.
You have minutes to decide: which plant to you keep running in order to supply power to run the emergency cooling pumps in the other reactor cores.
Nuclear war declared on Greenpeace & whales.
The news coming from the BBC and the news on Japanese TV seems to be different and randomly changing .. I presume from the language barrier/technical nature of the subject involved. Japanese TV is saying "not much as happened" and then the BBC is saying "the sky is falling".
Although i know it's the standard image used for "nookeler disaster (TM)" I think, on this occasion, the use of the mushroom cloud image to illustrate this story in your highlighted headlines banner (or whatever you call it) at the top of the page, is a bit insensitive, given Japan's previous historical association with things nuclear.
> This is blasphemy! This is madness!
THIS IS EL REEEEEEG!
Has anyone else noticed the BBC rolling out a load of nuclear experts with the word 'Grim' in their surname?
was the glory of steam travel forgotten so quickly? You have an energy source for pumps - steam.
Send Bishop, it's the only way to be sure. Mostly.
a by-product of nuclear fission and released as fuel rods break down under intense heat and pressure. If they do have "A Big Red Button" then they better push it now and start praying. Better to trash the plant, (it's been operational since 1971!), than risk the lid popping off and releasing even more cesium-137 and other nasties. Either way the poor sods haven't got a chance with that one. And with 9 other reactors, (not all operational), in the vicinity and a fairly dense local population 100km would seem a sensible, minimum, exclusion zone. If you are going to put nuclear facilities on the coast, and who doesn't, then apart from building them to withstand seismic shock, you've got to ensure sea water ingress just can't happen to any part of the facility. Large-scale nuclear accidents are relatively few, but when they do happen the potential impact ain't so good.
I know this may seem like a daft question, but why do nuclear power stations exist in a country that is in one of the most active earthquake zones on the planet? It seems like its asking for trouble, especially with so much potential for an environmental disaster if an earthquake damages a reactor, as is happening now.
Because getting cheap & plenty power over yonder any other way is somewhat problematic. Or at least it was when they started building the things. It might possobly be different now.
Japan is one of the most earthquake- and tsunami-aware countries in the world. Considering its geography, the bad luck of such an unprecedented incident (an 8.9 hasn't been felt in Japan in recent history, so no serious information to work with) has been tempered significantly with planning. It's just that, in this case, even the best-laid plans go awry, especially when you get big tsunamis right after the quake: not giving people a lot of time to head for high ground.
To answer your question, people have been researching seismic isolation and other earthquake-mitigation strategies for decades. Japan and California keep trying out new ways to keep the shakes from toppling buildings and the like, and considering the magnitude of the quake, it seems it's been helping. Japan knows it has to live with earthquakes, so it plans for them (think of this: the Akashi-Kaikyo Bridge crosses a seismic fault line). Odds are the nuclear plants were built with seismic isolation. It wasn't so much the quake that's putting the plants on the brink but the flooding from the tsunami (blame that on lack of data: Japan hasn't had to deal with a tsunami this big in recent memory; California has that problem every so often as well).
Japan (it's an island, right?) has to import most raw materials, so if they used coal-fired plants, their harbors would always be full of coal haulers.
It was a tradeoff between constantly importing coal and the risk of an accident. I'm sure the engineers in the '60's and '70's did their best, after all, most of them knew very well what 'what's the worst that can happen?' really meant.
You do remember WWII, right? One of the first things that the Japanese did was to sieze sources of raw materials.
In fact, there was a very serious political debate about introducing all things nuclear into Japan, and earthquakes (and tsunamis) were in fact mentioned by the opponents to this idea...
Unfortunately, being an island state, with its relatively dense population, high energy demands and no natural fossil or renewable energy sources, Japan had little economically viable choice... Especially considering its less than friendly neighbors, getting a fuel pipe wasn't an option either (and such a pipe wouldn't survive an earthquake or tsunami either).
Of course, it would have been wiser to use a more inherently safe reactor design there... but such designs are only available recently - and the plant in question is 40 years old.
No local coal or gas resources.
Japan is the single largest importer of Australian coal (not sure whether that be fuel coal or coking coal or Old King Cole) so I would be guessing they already handle a shitload of the stuff.
Would there be any left for other buyers if Japan relied soley on coal? Or would they have to buy all of it?
were given two or three rad exposure badges to use serially as one badge would have meant they could nto have done the overtime they were expected to do.
SO, yes a number of staff have been exposed to way beyond the legal limits but the onsite "Homers" could still tick the OK safety checklist when reviewing the rad exposrure meters.