"it managed a mere 16mm into the 5" thick concrete"
Not enough melted for it to reform into a critical mass. Same situation here. In China Syndrome, it goes critical again. It puts out whopping energy levels and there is nothing that can stop it.
The constant output of some low/med radiation is a concern. One assumes some part of a pressure vessel has a small crack from which steam is escaping. They need to locate and plug it. Nasty work.
I noticed in the recent TEPCO site incident reports that a quake last summer caused pond coolant to be displaced over the floor, and drip into a sump which ultimately lead to a small radioactive discharge into sea. This "leak" roughly corresponds with since they been spraying the ponds to refill them. So I wonder if displaced pond water is again the reason for a discharge to the sea.
Same situation here
Does anybody actually know for sure that the fuel rods have actually melted in this way or could it just be that they have overheated and damaged their casings?
The constant output of some low/med radiation is a concern. One assumes some part of a pressure vessel has a small crack from which steam is escaping. They need to locate and plug it. Nasty work.
I believe that this has been decreasing for the last couple of days now that they have been able to power up a lot of the onsite cooling pumps. They also suggested that the breach was in the torus at the base of the reactor which should be a lot easier to fix than if it is part of the main pressure vessel. I guess, until they can get in there they won't know for sure.
Buzz and mjb obviously aren't watching the same news channels as me because both report high levels of radiation in the air, a breached containment vessel for reactor 2 and continued releases of radioactive today from reactor 3 resulting in another evacuation of workers. Whilst the Japanesse PM reported contamination in a wide area. The good news was limited to the lights working again in the control room.
I find it fascinating how the pro nuclear folk deny that this is serious - potentially very serious.
No one actually knows how bad the damage is but it is clear that the situation is not under control in any meaningful way. We might get away without major release of radioactivity but we might not. There were far more fuel rods on site than there should have been, there is no proper cooling of the fuel rods and cores, containment has been breached. The cores are in an unknown state
I find it fascinating how the pro nuclear folk deny that this is serious
I'm not sure who the "pro nuclear folk" are - maybe linking to an article that's not all "doom and gloom we're all going to die" makes me one. I haven't seen anyone deny that it's serious, but to quote the BBC article -
[i]"Even under this worst case, though, the direct health consequences of the nuclear accident would be very small compared with the thousands already killed by the earthquake and tsunami, let alone the continued suffering of the survivors"[/i]
The Japanese first commenter on the BBC article puts it well:
...the media craze about the Fukushima plant in the US and European countries has nothing but amazed me. People thousands of miles away are more hysteric than we here in Japan. It is hard to remain objective in the middle of the disaster and I am very grateful for this so far one and only voice that I have found in the media that is calm and tries to put things into perspective
Personally I've always thought that it's a really bad idea to build nuclear reactors in areas prone to earthquakes such as Diablo Canyon and these Japanese ones. However, it appears from this incident that I may have been wrong; if minimising loss of life is your main criterion then preventing people from living in an earthquake zone should be your priority and the nuclear plant is almost an irrelevance.
Edit: I see that none of this is important any more, Elizabeth Taylor's death has pushed it off the BBC front page.
Depends what you think "control" means. There appears to be a modicum of control over the reactor temperatures, and the outcome looks somewhat better than it did, but still very uncertain. So I agree - not in control at this time.
high levels of radiation in the air
What is "high"? Enough to make the staff leave the site for a period to avoid breaking their dose limits. But without them on site, the situation is even less controlled. A nasty situation for the staff.
Whether it constitutes a health hazard beyond the site is unclear. There are already precautionary measures to avoid consumption of food from in the area; good. But I also read that there elevated levels in Tokyo's tap water - "twice the recommended safe level". If true or false, that could cause panic amongst a large population.
Whether it constitutes a health hazard beyond the site is unclear. There are already precautionary measures to avoid consumption of food from in the area; good. But I also read that there elevated levels in Tokyo's tap water - "twice the recommended safe level". If true or false, that could cause panic amongst a large population.
Lower than in cornwall I'd imagine.
The good news was limited to the lights working again in the control room.
The bad news was they were all flashing red.
Any way what ever the long term outcome is there is a skeleton staff of about 150 in there dealing with trying to mitigate a potential disaster. Hats off to them.
You might find radon gas dissolved in cornish water but a I doubt there's much thyroid cancer causing [url= http://www.nytimes.com/2011/03/24/world/asia/24japan.html ]radioactive iodine[/url]
That was the first Google result so you don't have to look far when you know what to look for.
Quite likely this has been posted already (it was on another thread a few days ago) but if not, this chart translates the levels of radiation being quoted into laymans terms.
Program just started on Radio 4 about what's the future in the UK of nuclear for those interested.
Buzz and mjb obviously aren't watching the same news channels as me because both report high levels of radiation in the air, a breached containment vessel for reactor 2 and continued releases of radioactive today from reactor 3 resulting in another evacuation of workers.
I am, i just choose to read further than the attention grabbing headlines. Did you see the expert calmly explaining to the BBC reporter deparately trying to get a story that the high radiation levels reported (400mSv/hour) were a short term spike recorded by a sensor on top of the reactor building and that by moving to the next building they dropped markedly, by the time you reached the plant perimeter it had dropped to the equivalent of 3 years background dose (8.5mSv/hour) and by the time you got to the edge of the evacuated zone it was negligible.
I find it fascinating how the pro nuclear folk deny that this is serious - potentially very serious.
Where did i say it wasn't serious? Of course it's serious, it just hasn't turned into the appoclyptical event that the media wanted it to.
it is clear that the situation is not under control in any meaningful way.
The fact that 3 of the reactors are now back on mains power, have their sensors and cooling pumps back on line and have reached a state of cold shutdown suggests that at least some of this situation is under control does it not?
You might find radon gas dissolved in cornish water but a I doubt there's much thyroid cancer causing radioactive iodine
Of course you realise that it is very easy to prevent radiation poisoning from iodine 131 by simply taking iodide tablets (which the the Japanese government have given out to everyone in the area). You must also know that it has a half life of only 8 days so there are no real long term issues with it .
(which the the Japanese government have given out to everyone in the area)
Which the Japanese government admitted they didn't give out to the surrounding are quickly enough (3 days delay I think) as well.
no real long term issues with it .
Unless of course you have managed to consume some in the those 8 days or the output from the plant has been continous for the last 10 days or so which could potentially mean 3 weeks of radioactive iodine in populous.
Which the Japanese government admitted they didn't give out to the surrounding are quickly enough (3 days delay I think) as well.
My understanding (and i may be wrong here) is that they have only handed them out to save time in the future should things get worse. The radiation levels outside of the cleared zones have never been high enough to require the pills to be taken. Interestingly several countries around the world are now havng to make announcements to tell people to stop taking anything they can find with iodine in it (wound cleaner, salt etc.) as they panic over the news reports!
Unless of course you have managed to consume some in the those 8 days or the output from the plant has been continous for the last 10 days or so which could potentially mean 3 weeks of radioactive iodine in populous.
This highlights the point i'm trying to make, you haven't looked at this any deeper than the sensationalist headlines. If you had have done you would know that the output from the plant hasn't been continous and levels of radiation received by the public outside of the exclusion zone so far seems to have been neligible.
This highlights the point i'm trying to make, you haven't looked at this any deeper than the sensationalist headlines. If you had have done you would know that the output from the plant hasn't been continous and levels of radiation received by the public outside of the exclusion zone so far seems to have been neligible.
Again, you have what the nuclear authorities want you to read.
I'm pronuclear, but I'm suspect of any government when it comes to something that has this potential a scale to cause widespread contamination.
Who says that Liz Taylor wasn't killed off by the Japanese government to take their story of page 1.
Again, you have what the nuclear authorities want you to read.
I think i'd probably trust the Journal [i]Science[/i] to give a balanced overview:
http://www.sciencemag.org/content/331/6024/1502.full?rss=1
http://www.sciencemag.org/content/331/6024/1504.full?rss=1
Oh dear, #3 has done what the STW pro-nuclear brigade said it couldn't.
Edukate me - what exactly has it done (which the BBC doesn't appear to be reporting)?
Oh dear, #3 has done what the STW pro-nuclear brigade said it couldn't.
What? Kill thousands of people?
It looks like some workers have received radiation burns from water in the vicinity of the containment. Surely this radiation would be reported by their portable Geiger counters before they entered? I hope they are going to be OK. They need to find where the pressure vessel is leaking and stop it pronto or it will be increasingly difficult to work the problem.
Did you also read an account from one of the original designers who, at the time, complained that the design of the pressure vessel was too small? Not widely reported.
I have already read a TEPCO report that a previous earthquake revealed a route by which water displaced from cooling pools could escape to the sea. It would not surprise me if another route exists given the chaos surrounding re-filling the pools by hosing and helicopters (pretty desperate measure). I would also like to know where all the seawater they put into the reactor ends up.
And I read another report that neutron bursts had been detected near the site which, given that pressure vessels are structurally intact, suggests that cooling fuel rods in the cooling pools may have starting reacting when the water evaporated away! Surely storing spent fuel in a way that could start a chain reaction is dangerously against the rules? Pure speculation mind you.
The truth will out eventually and it will be vital lessons learned for the uranium reactor industry.
Sites evacuated again today due to 1000 times the level.
