Fukushima reactor core battle continues Tokyo Electric Power Co (TEPCO) has battled furiously today to prevent critical overheating of the core of the Fukushima nuclear plant's No 2 reactor. Following the failure of back-up diesel generators designed to maintain coolant flow, it fell to an emergency "fire pump", to keep the situation under control. This unorthodox …
i'm seeing some conflicting reports on this right now: nikkei.com mentions that all 3 reactors that were having trouble are now under 100ºC (article uploaded at 1:44am, japan time), but nhk is still reporting issues with the no.2 reactor (according to a press conference that happened shortly after midnight).
i'd really, really like to see this settled (preferably not the worst case scenario way) as soon as possible..
Something as important as nuclear fuel rod cooling would warrant a few 55gal drums of diesel fuel from the carrier, if only out of a sense of kinship from one nuclear powerplant to another, right?
But I did read (elsewhere) that, essentially, someone wasn't paying attention to the pump. In the fog of miscommunications that really could mean anything in this case, one possibility certainly being "they couldn't scrape up the necessary fuel in time to keep it going" in the probably hideous logistics environment which is currently northern Japan.
Then again, if your diesel generator or pump has been recently submerged under umpty-something thousand gallons of seawater, getting your paws on a few 55 gallon drums of fresh diesel for it is the least of your problems in getting it going again.
Once it's sucked seawater though it's fuel system, it's pretty much screwed. You'd be looking at a complete strip and clean of the fuel system as a minimum here. Oddly enough this is one of the places where an old skool carb fed petrol engine wins. I've personally started up petrol engines after complete submersion after nothing more than emptying the carb float chamber and then spinning it over with the plugs out to spit out any water. It helps here that the petrol engine will stall as soon as water reaches the electrics, whereas a diesel will keep running 'til it gets water instead of fuel and / or air, or "way too late" as we like to call it.........
There was no need for any US ships to bring in fuel or anything else for the sites. The offer was turned down for US Milt. asst.... Japan's Gov asked for asst a few hours after the quake and Clinton then had the USAF scramble up some planes for coolant + fuel and readied it for drop shipment to the sites. It was all set and ready to go but the Nippon Gov . they retracted their request for help .
So - thank God - we are not talking about a second Chernobyl, just about a few billion Euro down the drain.
I'm so happy that economics never, ever seem to be a consideration in nuclear power play ...
shame on you for Mr. Page's premature triumphalism and for the cheap shot at the end of this article.
Because disasters in oil refineries just cost pennies to fix. Because an oil spill just takes a couple of days to clean up with no effect in the environment. Because fires in oil facilities are extinguished in moments and leave nothing bad behind.
Yea, clearly economics in nuclear energy is all messed up buy they are absolutely perfect for oil.
FFS, people can someone put into perspective the brilliant work of whoever designed the plant.
It was designed 40 years ago and it has survived a 9 on the Richter scale and most of it is still in place after a several m tsunami.
And that is a plant designed _BEFORE_ Chernobyl.
If the release after an event on this scale is this small all I can say bring it on, I would not mind having one in my backyard as it is clearly safer than having a petrochemical refinery. All those are still burning, right?
or - let's talk about a cheap and greedy design that exposed the underlying cheapness and greediness and utter lack of even superficial technical knowledge of the hypocrites who had commissioned this design.
That, plus a failed and criminal war against the Afghan people brought down a thoroughly despicable regime.
Could never happen in the free west.
Let's simply pray and hope that the containments hold.
BTW - the 9 was measured at the epicentre, on site the quake's strength was below specification.
"That, plus a failed and criminal war against the Afghan people brought down a thoroughly despicable regime."
i cant' quite see how this quake will topple the merkin political system (thats is the corrupt regime to which you refer?) but what the hell, if it brings the merkin people blinking into the light of freedom from tyrany, i am all in favour.
Seeing as how the Bank of Japan injected $85.5 billion into their economy yesterday, I suspect a few billion Euro is really neither here nor there when compared to the effects on the local area of a Chernobyl type event.
The 'cheap shot' at the end of the article wasn't that cheap and fully deserved by most of the 'journalism', I hesitate to use that word based on the quality of the coverage, employed to cover the events in Japan.
Yeah well, this is just paper money, not real savings being liberated.
In a sense, a tsunami of nicely printed paper. Once the new "riches" have sloshed through the economy you are still at the same point than you were at the beginning.
So yes, one reactor may still kick the bucket. However that's one in three - and even if it does go down, it will quite likely not be the nukapocalypse mainstream press is alluding to. I think that under these circunstances Lewis' account is still pretty close to the truth, much closer than the Beeb will get you anyway.
so yes, one still left standing (http://www.theregister.co.uk/2011/03/16/fukushima_wednesday/) ...
I come to the register because - up to now - I had faith that writers als well as commentators had a firm grasp of the technology discussed. (I admit that I did not expect sneak reviews of an article, but well, one lives to learn)
Having a firm grasp means that one knows ones half-times when talking about radionuclids and that one knows a micro- from a milli-something. So far, you might think yourself entitled to feel superiour to the BBC.
Having a firm grasp however also means not jumping to conclusions on the third day of a highly critical procedure that is bound to run for about a week before it can be called safely concluded even in normal times. You might therefore reconsider your attitude toward the BBC (for historical reasons a very trusted source of news in my country + it seems they were right)
Even if this desaster might - hopefully - end without much loss of life, the economical viability of nuclear energy will be in grave doubt.
What's this cheap shot at the end of the article everyone is talking about? It currently ends with, "If the No 2 reactor's core does melt down, its steel containment vessel is designed to safely trap radioactive material."
It's not like it ends with something crass like, "If the No 2 reactor's core does melt down, its steel containment vessel is designed to safely trap radioactive material, thereby depriving doommongers of a Chernobyl-style catastrophe."
An old Japanese man interviewed some time after the end of WWII said that even though the Japanese officials kept trumpeting about their great victories in the pacific he knew they were losing the war because each victory was closer to Japan than the last. I was reminded by this when hearing japanese officials saying how the problems in their nukes were being overcome, each intervention seems more desperate than the last.
Were I religious I would pray.....
Yep, the Japanese authorities have it all under control - that's why they're asking for help from international sources. Personally I wouldn't fancy being inside that control room since so far it makes a Godzilla movie seem tame. I especially liked the cheery part about the roof being blown off constituting 'cosmetic damage'. Hopefully we don't move to the next stage 'collateral damage'. Oh what's that, we're already there?
The roof demolition was unfortunate but it occurred outside the pressure vessel designed to hold the reactor through a meltdown: the structural integrity of the important parts was not affected at all. The vast majority of "radioactive material" released was a nitrogen isotope with a half-life in seconds. This is really the most worry-free nuclear-plant accident I can imagine, and given the unprecedented size of the quake and tsunamis, it was a brilliant performance on the part of the engineers and technicians. Bravo!
RMBK design reactors (what was built and exploded at Chernobyl) are graphite moderated: essentially big blocks of graphite full of nuclear fuel, and they did not have a high-strength steel containment vessel surrounding the core.
The Fukushima reactors are light water designs: the cores are not full of flammable material and they do have high strength steel containment vessels.
What happened in Chernobyl that made it a type 7 nuclear disaster was that not only did the core explode, but that set the graphite on fire. So you had burning carbon mixed up with nuclear fuel & bi-products.
I am not saying the JP reactors are cute and cuddly as kittens... a light water reactor that loses cooling for too long will melt down. However in the case of a melt down in a light water reactor, you do not get towering clouds of radioactive smoke like you can get from a melt down in an RMBK. There is no obvious way for the melted fuel to disperse in the manner that happened at Chernobyl.
The situation at Fukujima I & II is not good, far from it, but even in the worst case a Chernobyl scale disaster is pretty unlikely.
I feel that you are right on the money here :) You must have read the Chernobyl Disaster wiki; what a fascinating read. I hope you are absolutely correct and that no unforeseen physics or materials get included in the melt that breaches the containment vessel.
Colby in California
Had a read of that article yesterday myself. Being honest I found a lot of it hard to follow but from what I've been able to understand the Fukushima reactor and the Chernobyl reactors are very different beasties.
As for the whole nuclear debate, is *now* really the right time, when people are risking their lives trying to bring the reactors under control?
Thanks, but not precisely. I was 20 years old when Chernobyl happened, so got to experience the thing as a fairly aware young adult. I'd have made the same comments about RMBK 5 or 10 or 15 or 20 years ago.
Graphite core was recognized even before that as a dangerous design.
BTW: guess where the USA built graphite core reactors? At Hanford, to breed plutonium for bombs, they were approx very first generation reactors. Hanford Nuclear Reservation is acknowledged by the USA federal gov't as being contaminated all the way to groundwater and in need of remediation. AFAIK USA & western democracies moved away from graphite very early, not many were built outside the USSR.
I think we need to collectively extend the idea of 'defense in depth' of reactor designs to include millennial disasters like Japan's earthquake - thus not merely strong containment vessels but hardened backup power sources and coolant sources. As Lewis and Lester have pointed out, not a lot of people have died from reactor failures: however, serious reactor failures have the potential to kill a lot of people and poison a lot of land.
What Lewis & Lester have avoided is the problem of measuring contamination and the total effect of a nuclear accident. Hot spots around Europe have been found years & decades after Chernobyl that isotopically can be tied to Chernobyl. It's like measuring weather - we can only measure a sample of the the space or area... it is known that such measures cannot tell the whole story... else we could predict the weather accurately... the actual degree and distribution of contamination in Japan will not be known for some years. It may be as Lewis & Lester claim that there is nothing to see here, but equally because we know a fair amount of leakage has occurred and we do not have the ability to say exactly where that stuff went, there is no reason to believe Lewis and Lester are correct.
How many coal miners are killed yearly while supplying product for power plants? How many workers are killed in the petrochemical industry yearly? Contrast that with the number of people who have been killed as a result of a nuclear power plant. Given that the reactors have been through conditions far more extreme than imaginable and that a significant number of problems cooling the rods down were directly attributed to human error, I still contend that nuclear power is far safer than all the alternatives.
FFS! If you must make comparisons, compare like with like. How many miners are killed digging out uranium or get cancer because of the job's exposure to abnornally high levels of background radiation? If you had a choice, would you prefer to have a job that meant you got coal dust or uranium dust in your lungs? What about the mortality rates for those who reprocess spent nuclear fuel or enrich it? And if you want to compare rates with power production, what are the death rates for those who work in gas/coal/oil fired power stations or hydro plants? How do those stack up against nuclear power stations?
BTW if you think "nuclear power is far safer than all the alternatives" - WTF? - no doubt you'd choose to live next to a nuclear power plant (or reprocessing plant) instead of a nice cuddly wind farm or even a coal mine.
Will it be OK to store a few tons of radioactive waste in your garden or the same amount of coal ash?
at about 6h10 a blast sound was heard from inside the No.2 reactor. it looks like it happened inside the suppression pool, and it might have been damaged (and thus be leaking contaminated water) -- this is nothing more than speculation at the moment though. also, the pressure inside is decreasing and the radiation levels are at 882 micro sievert. some workers from the No.1 reactor have been temporarily evacuated.
this is what i managed to understand with my broken japanese.. it's not 100% reliable info, but i tried my best :P
http://en.wikipedia.org/wiki/Fukushima_I_Nuclear_Power_Plant
"The plant consists of six boiling water reactors. These light water reactors have a combined power of 4.7 GW, making Fukushima I one of the 25 largest nuclear power stations in the world."
The reactors for Units 1, 2, and 6 were supplied by General Electric, those for Units 3 and 5 by Toshiba, and Unit 4 by Hitachi. All six reactors were designed by General Electric. Architectural design for General Electric's units was done by Ebasco. All construction was done by Kajima. Since September 2010, Unit 3 has been fueled by mixed-oxide (MOX) fuel, rather than the low enriched uranium (LEU) used in the other reactors. Units 1–5 were built with Mark I type (light bulb torus) containment structures, Unit 6 has a Mark II type (over/under) containment structure.
Yes, you could design a nuke plant to completely withstand a massive tsunami, but it seems to me the designers figured it was pretty much going to be trashed by such an event anyway. This blog (now picked up by MIT) sets out how things are supposed to work and the observed issues and responses seem to match what the designers said would happen in this sort of exceptional circumstance.
http://mitnse.com/
I suppose they could have built the plant up in the mountains, but maybe if they'd done that, there would have been a massive avalanche that swallowed the plant whole instead. Monday's Experts and all that.
Yes, my initial homebrew attempt at reactor site design made me wonder why such plants are not built high up, but my guess is that a reliable source of nearby water is a vital design component, and the proximity to the sea in this case seems to have been useful for emergency cooling. A mountain top nuclear power plant is probably a lot harder to access (everything needs to be airlifted) and you couldnt easily guarantee water when you really needed it.
I'm bored programming shit. Nuclear power plant design seems to be where its at. Where do I sign up? Ill bet after this General Electric and the japs will design and build plants verging on sci-fi levels of safety (I'm already impressed / jealous at the fantastic job they appear to have done already, I hope the guys who designed it get medals).
and no personal slur intended, but from the sowtware industry you do not have even the beginnings of a glimmering of an inkling of the meaning of the word reliability.
you drop a bollock on one of these designs and there aint gonna be a 'patch tuesday' comming around any day soon to dig you out of the hole.
Nuclear plants in the mountains would be much worse in disasters. Any local fallout of radioactive particles would be carried in the run-off from the mountains and would have the potential to contaminate a massive area. Also, the elevated position would spread any such fallout wider to start off with.
You pays your money, you makes your choice.
... as with so many (and not just in Japan) is the arrogance of the government. There should have been a request for help days ago - that must have been clear to almost everyone. If, as I seem to be hearing, the key to preventing the escalation of the problem from "loss of emergency cooling" to "we're going to have a meltdown" (which I know doesn't have the apocalyptic meaning some would ascribe to it, but which is *very* bad PR), was "we need some pumps with power plants and some fuel", then that request should have been made early. Indeed, as I understand it, the request was made by the people on the ground, but someone in a ministry somewhere reversed it.
Once this is all over, it would be good to see a proper investigation so that heads can roll - and I doubt that many at the real-work end will be found wanting.
I'm just glad to see they're asking for help now, rather than waiting till it's too late.
Good on them for that. It's no reflection on the staff on the ground of course, nor on Japan's tech capability. Sometimes events spiral a bit and it's helpful to have an outsider look at the situation. While some countries would be more inclined to pull an iron curtain round and secretly hide their tech, this is the proper way to go about it. Other countries, take note !
OK, so the outer containment vessel is going to contain the melted fuel rods. That's nice. But how long will each nuclear mausoleum remain dangerously radioactive? Tens of thousands of years? Long enough for many more 9.0 earthquakes and tsunamis to hit? Can they be "cleaned-up" without risk of contaminating the surrounding area or reducing the life-span of the poor sods assigned to do the clear-up? How much will it cost to police and maintain the failed sites? No answer? Thought not...
The steel containment vessel surrounding one of the reactors at Fukushima has been breached. The last line of defense is gone, the material inside the core including the fuel rods are now freely interacting with oxygen and igniting. Radioactive materials are melting. Emergency workers who have desperately brought sea water in to the reactors and risked their lives these past 3 days have been pulled from the plant.
They have left.
I wanted to believe that the plant and its amazing design would make it. But I think this disaster is going to win. I think this is a terrible tragedy for the Japanese people, and the world. Nuclear energy is also a triumph, don't read me wrong. But, I think Mr. Page spoke too soon.
There is an AMAZING article on Wikipedia about the Chernobyl disaster. If you are finding yourself compelled by this natural disaster at the Fukushima plant in Japan, read about the accident at Chernobyl. And pray for the Japanese :) http://en.wikipedia.org/wiki/Chernobyl_disaster
Colby in California
http://www.world-nuclear-news.org/RS_Possible_damage_at_Fukushima_Daiichi_2_1503111.html
(via http://mitnse.com/)
"Confirmation of loud sounds at unit 2 this morning came from the Nuclear and Industrial Safety Agency (NISA). It noted that 'the suppression chamber may be damaged.' (...) Also known as the torus, this large doughnut-shaped structure sits in the centre of the reactor building at a lower level than the reactor. It contains a very large body of water to which steam can be directed in emergency situations. The steam then condenses and reduces pressure in the reactor system. One effect of this is that the water and steam in the torus will exist alongside a range of gases produced by the nuclear processes in the reactor.
"The pressure in the pool was seen to decrease from three atmospheres to one atmosphere after the noise, suggesting possible damage. Radiation levels on the edge of the plant compound briefly spiked at 8217 microsieverts per hour but later fell to about a third that.
"In line with the theory that non-condensed gases in the torus will be released fairly promptly and not replenished at the same rate, it is possible that the radiation release - at least via this route - will dimininsh and stabilise.
"A close watch is being kept on the radiation levels to ascertain the status of containment. As a precaution Tokyo Electric Power Company has evacuated all non-essential personnel from the unit. The company's engineers continue to pump seawater into the reactor pressure vessel in an effort to cool it."
"A message recieved from Tepco at about 5pm said the primary containment vessel around the reactor and secondary containment provided by the reactor building 'show no significant change.'"
So yes, more radiation has leaked this time - but still it's irradiated water. The reactor's containment remains in place, and the cooling work continues.
I've been in Tokyo for 10 years and I'm getting on the next plane out of here.
TEPCO and the government is full of it. Most foreigners I know here are either packing or already gone.
Some went south and now are leaving the country, some other are going straight back to their home country.
At each press conference, the government + TEPCO gang carefully adds a little bit more bad news. Rationing the ugly bits to avoid panic, and now not even willing to answer what's the risk for metropolitan areas being affected by radiation contamination.
They are relying on the Japanese population ability to adapt, and perhaps there is nothing else that they can do. I can take the aftershocks, I can even risk another big quake in Tokyo.. but there is no messing around with radiations.
I hope that I'm wrong and that I can come back soon.. but foreigners here are smelling the BS and aren't willing to take it.
Another explosion at the Fukushima Daiichi2 early Tuesday. "Now we are talking about levels that can impact human health," Chief Cabinet Secretary Yukio Edano
Radiation reading at 0831 local time (2331 GMT) rose to 8,217 microsieverts / hour from 1,941 about 40 minutes earlier. -TEPCO
Japan's nuclear safety agency said it suspects Tuesday's blast may have damaged the vessel that holds reactor 2
Tokyo is recording raised levels of radiation but these have not yet reached anything considered unsafe.
Agree with others who have noted that the media coverage of the technical aand safety aspects of Fukushima has largely been a pile of shite, swallowing and regurgitating official reports and industry connected "experts" glib reassurances without question or any real analysis.
And others who have noted the official Japanese govt methodology, to dish out the bad news bit by bit, so we don't choke on it all right away.
So much misinfo put about by"expert" commentators; like our own Prof Beddington on the Today programme this morning:
http://news.bbc.co.uk/today/hi/today/newsid_9425000/9425087.stm
"Now don't you worry children, trust us experts, no dangerous, nasty radioneucleuotide things are gojng anywhere near population centres, like Tokyo, that's just not going to happen, ever. 30 clicks is fine, I'd take my grandkids there no problem." That's all OK then.
So it (probably) won't be a Chernobyl, but remember exactly how bad that was, and Japan is about as densley populated England, so any long term contamination in the region will have a proportionately much greater impact than in the relatively sparsely populated Ukraine. With Chernobyl, the Russians only lost it on one of the reactors, and spent hundreds of lives in order to help sort it out / clean up. Fukushima looks like it could well involve three reactors.
Bring back Raymond Burke - or was that Biddy Baxter. Neither could do a worse job than some our our own beebs "science correspondants" - and they're both dead already!
I think I should add this: in a BWR, during a melt down, apparently the temp cna get high enough that the metal making up the fuel rods can burn. This is a few hundred or thousand Kg of material, compared to many many many thousands of Kg of graphite in Chernobyl RMBK.
Still, there is a large amount of fuel in the rods (order of magnitude or so in the core compared to Chernobyl) - so if the rods did or do burn, it seems reasonable to expect the smoke should be that much more contaminated given it's smaller volume... with the vagaries of air flow that might result in more intense contamination where the smoke settles to ground, depending on how much it diffused.
The result is still a crap shoot as far as I can tell.
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