March 12, 2011
Nuclear explosion in Japan
There's been a nuclear explosion in Japan.
The Fukushima reactor has blown up after the earthquake and the following tsunami.
As that article asks, what is actually going to be the effect of this? Are we about to see another Chernobyl type disaster? Or are nuclear reactors really as safe as their manufacturers say they are?
So, as far as we can tell at the moment, the radiation coming from the Fukushima explosion is 1/3,600,000 th of the radiation from the Chernobyl explosion. This isn't quite right for a number of complicated reasons (for example, we don't know how far the Japanese radiation will spread, what the total release will be and so on) but it does give an idea of the relative magnitude.
It is 0.00002% of the Chernobyl levels of radiation.
Another way of saying the same thing is that if you were standing at the reactor now you would, in one hour, receive the usual permitted level of radiation for an entire year. About half what you would get if you had a medical CT scan (which is 2,000,- 2,200 micro sieverts). This is of course a very, very, much lower level of radiation than at Chernobyl, where workers got in minutes amounts that killed them.
We just don't have enough information at present but we most certainly are going to find out. Is nuclear power safe or not?
September 21, 2007
What to do About Nuclear Proliferation?
Or, more importantly, what to do about the stocks of plutonium that we have?
The amount of plutonium stored at Sellafield has nearly doubled in the last decade to 103 tonnes. A quarter has been separated for foreign countries and companies. Prof Boulton said: "Just over 6kg of plutonium was used in the bomb which devastated Nagasaki, and the UK has many thousands of times that amount. We must ensure this very dangerous material does not fall into the wrong hands."
The society does not raise specific concerns about the security or safety regime at the Sellafield store. But it says the consequences of a security breach or accidental dispersal of the material are so severe that changes must be made.
It says the best option is to convert the plutonium into mixed oxide (MOX) fuel pellets. "If the government builds a new generation of nuclear power stations, the entire stockpile could be burnt as MOX fuel in these new reactors," the report says.
Yup, we should build new nuclear plants so as to reduce the risks from nuclear materials.
May 05, 2007
Iranian Nuclear Reactor Advertisement
Something of a flurry over the pond about the Iranians running an advertisement looking for bidders to come and build two nuclear reactors. Claudia Rosett picks it up for the newspapers, Eye on the World has the ad itself, Protein Wisdom as well, more and more.
Everyone seems to think that this will aid Iran in production of a nuclear bomb and that therefore this is an extremely bad idea. However, it doesn't actually help them get a bomb very much and they have a perfect legal right to own and operate such reactors.
Here's the thing. Operating a nuclear reactor doesn't get you very far in trying to build a bomb. It's neither necessary nor sufficient in fact.
Depending upon which path to a bomb taken, there are however two things which are neccessary.
If you want to build a uranium bomb (the easier of the two) running a reactor is in fact entirely a distraction. You want highly enriched uranium (80% or so) and you don't get that out of a reactor. Rather, you get that from an enrichment plant, which the Iranians have already said they are building themselves. (You feed the reactors they are looking for on 3%, or low enriched as well.)
If you're looking for a plutonium bomb then yes indeed, you do want a reactor. However, a light water reactor, pressurised, as they are asking for, is not the type which you would optimally use to create the plutonium. In fact, one of the various offers to North Korea is that they'll be given one of these reactors as long as they close down the one they have, which is optimal for producing plutonium. Further, you can't simply take out the fuel rods and then get the plutonium. For that you need a reprocessing plant....something which they've not tried to build and which no one, not even the Russians, will sell them (it's been mooted and then rejected).
The odd thing then is that by advertising that they want to buy these reactors Iran is actually suggesting that they really do want to have nuclear reactors, not bombs.
Or maybe it's all show....a pretty cheap thing really, buying an advertisement.
April 22, 2007
Chernobyl Radiation Exposure
So it looks like the Soviets did indeed seed the clouds to stop radiation getting to Moscow and so on.
This is a little odd though:
Alan Flowers, a British scientist who was one of the first Western scientists allowed into the area to examine the extent of radioactive fallout around Chernobyl, said that the population in Belarus was exposed to radiation doses 20 to 30 times higher than normal as a result of the rainfall, causing intense radiation poisoning in children.
Background is about 3mSv, so he's saying that children received 60 to 90 mSv. No, I'm not an expert on radiation exposure so I've no idea whether that would indeed trigger intense radiation poisoning. But given that a CT scan is 10 mSv, that implies that 6 to 9 of them will trigger intense radiation poisoning.
Which seems a little unlikely, doesn't it?
April 03, 2007
Chernobyl Estimates Again
Gaah, again, people are over estimating the deaths from Chernobyl.
Air pollution in major cities may be more damaging to health than the radiation exposure suffered by survivors of the 1986 Chernobyl disaster, according to a report published today.
The study suggests high levels of urban air pollution cut short life expectancy more than the radiation exposure of emergency workers who were sent into the 19-mile exclusion zone around the site straight after the accident.
Two explosions at the Chernobyl reactor killed three people immediately and more than 30 died from acute radiation poisoning, but the radioactive plume released from the reactor spread over most of Europe and is estimated to have caused up to 16,000 deaths.
Estimates actually range from hundreds of thousands (various loonie green groups) to a few hundred (the IAEA, the international authority on such things). Of cancers still to come the IAEA estimates some 3,000 deaths total. If Chernobyl is going to be used as a comparator then wouldn't it be a good idea to actually use the correct numbers?
The latest study follows a report last month from the Royal Commission on Environmental Pollution which said air pollution was responsible for 24,000 premature deaths in Britain every year.
I don't doubt this at all. It's actually been one of the points that some people have been trying to get across for years: other forms of energy generation also pose health risks, quite possibly higher than those of nuclear.
The health risks associated with air pollution and passive smoking appear more severe. Pollution in central London increases mortality due to heart and lung disease by 2.8% compared with Inverness, Britain's least polluted city, while living with a smoker increases mortality by 1.7%, the study found.
That number will be used by the anti-smoking brigade, just you watch. Despite there being other studies (a huge on in California for example) which shows no such thing, we'll soon be hearing about the dangers of passive smoking as a justification for the ban in pubs. But this is about sharing a house with one, not about having a pint or two in a smoky atmosphere. But the statistic will move from describing one situation to the other, don't doubt it for a moment.
In the journal BMC Public Health, Dr Smith writes: "Populations still living unofficially in the abandoned lands around Chernobyl may actually have a lower health risk from radiation than they would have if they were exposed to air pollution in a large city, such as nearby Kiev."
Never been to Kiev but if it's anything like Moscow I can well believe it. Rather shows how safe nuclear is really, doesn't it?
Dr Smith said the aim of the report was to put health risks from radiation in context with more familiar threats. "We can all face such risks just going about our ordinary daily lives," he said.
Quite. Everything always involves trade offs. So, given climate change and the point made here that nuclear is actually less damaging than urban air pollution, let alone the emissions from things like coal fired power stations, why aren't we already building a new generation of nukes?
March 10, 2007
Uranium in the DRC
Via Instapundit this at the BBC.
There's two entirely different stories being mixed and matched here.
1) The mining of uranium. Yes, the Congo has vast reserves. Yes, it's where the materials for the Nagasaki and Hiroshima bombs came from. However, what is mined in the DRC (and I'm not at all sure that any of the mines are currently open, in fact I'm reasonably certain that they are not open at all) is uranium ore. It might be that they have a capability to produce yellowcake, the next stage, but even if there are mines open and producing that would be it. This is the same stuff that Joe Wilson was sent to Niger to report on. It's also the same stuff that turned up in a shipment at Rotterdam.
It's a concentrate of uranium oxide(s). This is the raw material and it contains about 0.7% U 235, which is the material you want to run a reactor or to make a bomb. For a reactor you concentrate it up to 3-4 % (or sometimes 20% for a research or isotope producing reactor) and for a bomb you want much higher numbers, like 80%.
Now, the thing about this is that the factory needed to do this is extremely expensive, massively so. $10 billion is a reasonable estimate. It's actually what we're worried about with Iran and North Korea. Sure, have a nuclear power plant all you want, use as much 3% enriched uranium as you want, but we'll take the fuel rods back so you can't get the plutonium....and please, don't go building that $10 billion factory because we're not sure you'll stop enrichment at 3%.
But the connection between all of this and the DRC? As above, I'm pretty sure that there is no uranium mining currently going on in the DRC.
2) However, there was a research reactor in the DRC. A visit to it is ably described by Michaela Wong in In The Footsteps of Mr. Kurtz. This was (from memory) a research reactor and used the 20% enriched uranium. This again isn't good enough to use in a bomb (although it could make the basis of a pretty nasty dirty bomb).
There's no particular reason to think that people building a uranium enrichment plant would be interested in the small amounts of this material that could be taken from a research reactor. It's not a large amount, and while it would aid a bomb making program, it wouldn't aid it very much.
However, those (unlike Iran and North Korea) that did not have such capabilities might well be interested in the material. They wouldn't be able to make an atomic bomb but they could a dirty one.
As to sales of this material on the black market? Sure, could happen. But it's worth noting that many if not most of the buyers out there are actually people from the various agencies trying to soak up exactly this type of material. They pay top dollar for it too:
In 1992, Kazakhstan rebuffed efforts by Iran to buy beryllium from a storage site that also contained more than 600 kilograms of highly enriched uranium, enough to make dozens of nuclear bombs. Two years later, Washington secretly flew the fuel out of the country to prevent Iran and other would-be nuclear powers from acquiring it.
The gossip is that $30 million changed hands for that 600 kg.
Story 1 I really don't think is a problem, Story 2, well, certainly there's nothing new there and I would be amazed if the actual buyer of that material (if anyone has indeed bought it) didn't have a desk somewhere in or around Langley.
December 17, 2006
Russian Nuclear Fuel for Iran
Sorry, I don't get what the problem is here:
RUSSIA is to begin supplying Iran with nuclear fuel early next year despite mounting concern in the West that this could accelerate Tehran’s plans to build a nuclear bomb.
Why would this accelerate a bomb program?
Spent nuclear fuel produced at the Bushehr plant is to be sent back to Russia for storage and the process will be monitored by the International Atomic Energy Agency. But there are fears in America that Iran will find ways of siphoning off spent fuel containing plutonium, which could be used for a bomb.
This is actually what we want Iran to be doing!
Look, they have a right (whether they should or not is a different matter. They do.) to civilian nuclear power. What we're all worried about is that they'll build a bomb. But to build a bomb they must do one of two things. Either they must enrich uranium to HEU or, they must process plutonium out of used fuel rods.
Now, originally, the Russians were going to build an enrichment/recycling plant for the Iranians (I was actually told this in the offices of Atomenergoexport a decade or more ago). They've dropped that idea. They are providing already enriched fuel and will take back the spent rods for processing.
This is what we actually want to happen: that Iran gets civilian nuclear power without building the rest of the infrastructure that would enable them to build a bomb. So what's the problem?
Yes, I know that Iran is also working on cascades for enriching uranium, but that's a very different matter. This particular deal is just what we want.
Or is it that people would prefer it weren't the Russians making money out of this?
December 13, 2006
Faced with climate change of this speed, where do we stand on wind farms? Is it any longer tenable to wring our hands about intrusive pylons when the very survival of the countryside we care so much about is at stake? More to the point, does the man from Lewis, whose moorland view is about to be disturbed, have the right to stand in the way of an energy producer, which is one of the only currently available sources that is free of carbon emissions?
Err, needs to be said, again, that windmills are not free of carbon emissions. Actually, over the full cycle, the have very much the same emissions as nuclear. Which means that exactly the same argument could be made about the siting of a nuclear plant or of a waste disposal centre.
I have a feeling that people wouldn't accept that with reference to nuclear (Suck it up for the planet!) so why should they for wind?
October 26, 2006
Nuclear Waste Disposal
The Boy Mili does mean well I'm sure but he inevitably gets things wrong.
Local councils will be invited to volunteer to have an underground nuclear dump sited in their area in return for multi-million pound investment by the Government, David Miliband, the Environment Secretary, said yesterday.
Sigh. A multi-million pound investment by this lot is a debit, not a credit, to the life of an area. But the basic idea of offering a bribe is sound. It's just that it should be to the people of the area, not some level of government and not in the form of 'investment'. Cold hard cash please.
So you want to stick the waste under some village in Swaledale or something? There's 100 people living there? £ 500,000 each and away we go. Be a damn site cheaper and a great deal fairer too.
October 12, 2006
The Great Leader
The evil Kim Jong Il. Hobbies include huntin', shootin' and fission.