The used up fuel isn't contained in the same area as the reactor (it's up in the roof of the containment building IIRC). One of the exposions seems to have exposed this pond, which evaporated, or something... Anyway, I'm guessing that burning fuel rods without containment is very, very bad.

One definitely doesn't want radioactive stuff to burn into the air.

As for actual effects, they are really difficult to predict in any meaningful way at this point.

Direct exposure doesn't happen from this type of contamination. The concentrations are too small, the isotopes of incorrect kind. People don't just burn up or stuff. Very few people have ever been affected in this way.

There are two major factors - inhalation and ingestion. The immediate problem is Iodine. Body stores Iodine in thyroid. If radioactive version enters body it accumulates there and stays in body, irradiating from inside. The counter to this is Iodine pills which saturate the thyroid so it doesn't absorb any more. Due to quick decay, Iodine stops being a problem in a few days.

Bigger problem is Caesium with half life of ~37 or so years. After being blasted into atmosphere it falls on earth where it's absorbed by plants. Plants are then eaten either by animals or people and they enter body this way. With adequate infrastructure, this can be contained by destroying affected plants and animals. The affected area in this case is considerably smaller even in worst case, in case of Chernobyl it was basically entire Europe. There are some other isotopes, but they typically aren't important.

The contaminated area however cannot be left alone. Just like TMI, a large surface area must be cleaned, mostly to prevent accumulation of these contaminants (water, erosion). And picking up and packing several square meters of land is big task. This is also the reason why US fleet retreated - there is no point in contaminating entire carrier. Even if minimal, regulation classifies that as radioactive material and must be disposed. Would be a shame to throw away a perfectly good carrier.

This is supposedly from Tokyo, 200km away. Geigers are not calibrated, but 20 is often normal background. Another chart I've seen is from KEK facilities some 100km S and they correlate with this. The peak is 10 times background and it settles at some 3 times. So far, both of these are perfectly in accordance with what has been reported about explosions.

Simple fact is, stuff is leaking into air and being near the fires is bad. But overall, the scale here is much lower than anything Chernobyl related. Back then, 3 days later, the geiger was 50-80 (vs. 20) at 4000km away for a week or until major rain. It was just bordering on where one could still keep up counting. The difference is that back then, the reactor core blew up in the air and rest of it melted in graphite fire. Here, even if breached or overheating, is still in one piece and at least mostly contained. The other positive is that there is mostly water around, so most of the fallout will end up in the ocean where it dillutes.

So far, the reports that were given are quite accurate. Similar to in nature to TMI, just bigger, but not of global scale that Chernobyl was.

50 employees stay behind to stave off disaster.

This is going to be a movie or an anime. 100% guaranteed. Here's hoping that all 50 make it out alive with very little if any side-effects.

Nope...just think about it. They evacuated people within a 12 mile radius of the plant. Those workers are right at the center of it.

Their death is pretty much certain...which was confirmed by a nuclear engineer on a news report I saw earlier.

Yea I agree about the workers being F'd. I mean we (US) had a helicopter miles out days ago and we were scrubbing our people down and brought them back to a carrier even further away.

What I got from this article is that if the plant goes down and the generators fail => radioactivity IN YOUR FACE!

True, but again, scale.

This reactor generates ~3,000,000,000 Watts (3GW) of thermal power under normal operation, about a third of which is converted into electricity by a steam engine. No matter how you look at it, this is huge. And when hit by earthquake and tsunami combined, there will some side effects.

Meanwhile, the refinery is still burning => benzen in your lungs. Of course, nobody bothers to report that.
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Lets scale backwards. What if Japan only operated on nuclear plants? Could Japan have contained all the plants that could have get broken? How much damage the radiation from all those plants could have caused to the Japanese?

Lets scale backwards. What if Japan only operated on nuclear plants? Could Japan have contained all the plants that could have get broken? How much damage the radiation from all those plants could have caused to the Japanese?

Pre earthquake, they got 28.9% of their power from 55 plants. If that was 100%, they'd need 190 plants (55/.289). One in 55 is now FUBAR, so if they had've had 190, that would be ~3 FUBAR plants.

http://www.iaea.org/...miupdate01.html
Japanese authorities also today informed the IAEA at 04:50 CET that the spent fuel storage pond at the Unit 4 reactor of the Fukushima Daiichi nuclear power plant is on fire and radioactivity is being released directly into the atmosphere.[/quote]


This is a solid link. Informative and detailed updates every 3 hours or so.

As far as the situation goes, I am still of the opinion that all things considered the plant is performing well. With the exception of the plant having been bombed, it's been through literally the worst case scenario. Even though it is leaking radiation, the amounts are significantly less than a CT scan, and are on the order of about 3 times a chest x-ray. Obviously not good, but when compared with the potential for disaster this really isn't as bad as it could be, and I am thoroughly impressed.

Maybe I'm skewed by the risk vs. reward for nuclear power, but I think people are far too scared of the word radiation.

Lets scale backwards. What if Japan only operated on nuclear plants? Could Japan have contained all the plants that could have get broken? How much damage the radiation from all those plants could have caused to the Japanese?

The problem isn't containment. The plant is pretty much contained. The problem is containing it without losing the plant.

When compared to the damage of the earthquake and tsunami that caused the problem, the damage from the plant is nil. The plant could turn into a hydrogen bomb and cause less damage than the earth quake and tsunami.

The thing is that the human body deals much better with a short radiation spike (like from a CT scan or X-ray image) than prolonged exposure, even if both events average out to the same equivalent dose.

Add to that that the immediate radiation isn't even the worst thing once amounts of radioactive materials begin to accumulate in the food cycle. External alpha radiation is practically harmless but once anything with alpha decay enters your body (either by breathing in dust or eating contaminated food) you have a very, very big problem.




I'd like to point you into the direction of reading about the Goiânia accident. The nuclear material involved there is extremely tiny and localized compared to what we talk about in that reactor (and now a pretty big radius around the reactor) and have a look at the damage caused to get a feel for the dangers of radiation.

[quote name='owl' timestamp='1300250643' post='4786350']
Lets scale backwards. What if Japan only operated on nuclear plants? Could Japan have contained all the plants that could have get broken? How much damage the radiation from all those plants could have caused to the Japanese?

The problem isn't containment. The plant is pretty much contained. The problem is containing it without losing the plant.
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The problem isn't contained. The containment of at least one reactor is probably cracked and no one knows what is happening inside the reactors. More containment breaches, if they haven't already happened, are a distinct possibility. Let's not even talk about the situation of the spent fuel rods being stored on top of the reactors.

The whole situation at the plant is very far from controlled. This is a catastrophe in progress with desperate and highly unusual attempts to prevent an even bigger catastrophe and as it stands it is difficult to guess how it will end.

Anyway, the whole plant is already lost. Even if it were technically feasible (if extremely expensive) to salvage anything here, who would want a reactor which has already proven to be of a problematic design?

The thing is that the human body deals much better with a short radiation spike (like from a CT scan or X-ray image) than prolonged exposure, even if both events average out to the same equivalent dose.

Add to that that the immediate radiation isn't even the worst thing once amounts of radioactive materials begin to accumulate in the food cycle. External alpha radiation is practically harmless but once anything with alpha decay enters your body (either by breathing in dust or eating contaminated food) you have a very, very big problem.

I am aware of that. Maybe my expectation that after such an issue they would not perform a very thorough cleanup including testing of foodstuffs is expecting too much though. I would certainly hope that would be the case. :-/