Thursday, November 14, 2013

Windscale's Fatal Race for the Bomb

The Windscale Reactor
In the 1950s, Britain was pressured to develop its own nuclear bomb, in the hope to become a nuclear partner to the United States. As a nuclear power, Britain would retain its status as a superpower and a partnership with the U.S. could give them access to vital nuclear science.

The Windscale reactor, Britain's first ever nuclear reactor, was build to produce plutonium, the essential fission material for the bomb. Political pressure for an urgently needed success and the risks they had to take to meet the deadline had their inevitable effects on the security.

Britain cranked up the production of plutonium and tritium to keep up with the United States who by then already had their own hydrogen bomb. The aluminium cooling fins of the fuel cartridges had been reduced to dissipate less heat. The resulting higher temperature increased reaction in the core, producing more of the badly needed fission material they needed to produce Britain's own hydrogen bombe.

Not designed to operate under these conditions, the graphite core increasingly suffered from so-called Wigner energy, which caused sudden local heat releases at irregular intervals. On 10 October 1957, some of the refitted cartridges, containing enriched uranium and lithium-magnesium, caught fire and overheated the reactor's graphite core. The operators increased the airflow in an attempt to cool down the reactor, causing the fire to spread throughout the reactor core. The fire was eventually extinguished after 48 hours by pumping water into the fuel channels.

In contrast to modern closed-circuit water-cooled reactors, the Windscale design used airflow to control the reactor core temperature, evacuating excessive heat through a large chimney into the air. Consequently, the fire caused a release of nuclear material across Britain and Europe, making it both the first and worst ever nuclear incident in Western Europe, rated 5 on the 7-point INES scale (Chernobyl in Eastern Europe rated 7). The air-cooled core design, used for the first time in Windscale, has been abandoned since.

The truth about the cause of the Windscale incident was kept secret for political reasons. It was one of the more sinister episodes of the Cold War race for the bomb, and hardly mentioned in history. The dismantling of Windscale's iconic chimney started last September. More about this technically challenging work on the Sellafield website which includes the complete demolition program, and on World Nuclear News. The BBC website has some historical images of Windscale.

There's an excellent BBC documentary about the Windscale nuclear disaster that you can watch here below or alternatively via this youtube link.

5 comments:

P/K said...

Very interesting story... once again showing the madness of the nuclear arms race, which proved far more risky than they made believe us. We have been very lucky that all those near-accidents never turned into real disasters....

Fred said...

I was too young to remember the Windscale incident, even had it been made public at the time. But I do remember the Chernobyl incident because I was running an agricultural company in Britain at the time. The evening before the announcement that there was contamination affecting animals in North Wales, I was at a cocktail party where one of the senior civil servants from the Ministry of Agriculture was present. I heard then of the problem. Rain had carried the contamination over a thousand miles and dumped it on the hills of N.Wales, affecting the sheep over 300 hill farms.

In the event every sheep was scanned before entering the food chain. The flocks of young animals were brought down to lower altitudes, where less rain had fallen, to minimise exposure. I remember it as an eerie feeling that something nasty had arrived, as if from outer space.

After that I was travelling by plane and the person next to me was employed in the French Nuclear Industry. I mentioned that I thought Nuclear power stations were a bad idea. He stoutly denied this and quoted the perfect safety record of the French installations. His point was that with the right design and the right operatives the system was safe. Since the French will be building a new Nuclear station in England, I hope he is right!

Dirk Rijmenants said...

Well, every country has its stories about irresponsible use or dealing with nuclear problems. During the Chernobyl disaster, there's was a curious episode, involving our national weatherman, sort of a TV icon, with his famous hand-drawn weather cards he kept using.

The national meteorological institute had determined that the radioactive cloud would come over Belgium and particles would settle on crops and people's vegetable gardens (not to mention livestock that ate the crops). When our famous weather man was preparing to tell this on the evening news, he was ordered by the staff of the national TV (certainly on order from above) to keep this the whole event silent and tell that there the clouds would pass over.

Having the government keeping such information from its citizens was a pretty big disgrace and our weatherman wasn’t happy at whole, but he obeyed. Who knows what other things happened behind our backs in the past, both civil and military, causing of some of today’s health statistics?

Making safe nuclear plants isn’t technically that difficult. The problem, which already starts at the design, is that commercial profit is a primary goal to construct those reactors.

Fred said...

Why is profit a problem? I can't imagine any company building anything without it!

What may be a problem is reducing maintenance, training and other aspects necessary to run a safe plant in order to increase profits. This is the sort of thing that left-wing people often accuse companies of and I suppose it probably happens. One could certainly point to several industrial accidents where this could have been a cause. But then nothing is perfect (unfortunately) in this world and those who expect it to be are in for a big surprise.

My experience of hazardous plants is that people who work there are conscious of the dangers and take special care. The risk of getting hurt in such a plant is probably less than getting run over on the way home -- but now we are getting back to an older bone of contention between us!

Dirk Rijmenants said...

Fred, I don't see any bones of contention here. I'm pro nuclear energy (there's hardly any alternative to our energy-hunger) and believe it can be exploited safely.

However, commercial profit can lead to excesses. Just look at Fukushima and how TEPCO already before the disaster constantly had walked off the edges. They had been warned before, but its management, with a culture of striving for max profit, had no ears. Other plants in nearby, even harder hit coastal regions, did withstand the Tsunami perfectly.

Just to say that profit is OK, but not at the cost of security. Nuclear plants, at least most of them, are indeed statistically far safer than you crossing the street, but try to tell that to the Ukraine mothers and their children, and in 20 years to those who lived in the Futaba region. They’ll have other statistics.

If there’s one thing that I learned, it is that people are most creative in finding new and original ways to screw things up. It’s a talent that advanced us in many ways, but also kicked us in the butt, once in a while. Aren’t we humans great!