Japan: where the wind blows and spent fuel

If I hear another ‘expert’ on the tv news channels say that Fukushima is not as bad as Chernobyl I shall scream. For godsake there’s been multiple explosions, hundreds of thousands of people have been evacuated from the vicinity of the plant, large amounts of radioactivity have been released into the atmosphere, three reactors are in meltdown (one of them, No.3, uses fuel with a high concentration of plutonium), and equally worrying, today there’s been a fire and explosion at the spent fuel pool of reactor No.4. With regard to this latest incident, ‘TEPCO says the holes in the wall of the outer building at reactor 4 have left the spent nuclear fuel pool exposed to the outside air.’ (reports Reuters). This spent fuel is just as dangerous as the reactors.

Thus far, Chernobyl has been the world’s worst nuclear accident, rating a 7 on the International Atomic Energy Agency (IAEA) scale of 1 to 7, which gauges the seriousness of nuclear accidents. What’s generally acknowledged to be the world’s second worst nuclear accident also took place in the former Soviet Union, at a plant called Mayak, in the southern Urals. At the time a shroud of secrecy surrounded the Mayak plant and it wasn’t marked on any maps (when Gary Powers was shot down in his U2 spy plane in 1960, his mission had been to try and find out what was going on at Mayak). Thus what happened there became known as the ‘Kyshtym disaster’, Kyshtym being the nearest known town at the time.

The nuclear plant at Mayak was built between 1945 and 1948. During the early years of its operation they used to chuck nuclear waste into a nearby river (I’m not making this up). In the early 1950s they built a storage facility for the waste. The storage facility soon began to overheat (this heating effect is caused by the decay of the waste) and so they added a cooling system. In September 1957 the cooling system failed on a tank containing about 70 tons of waste. As the waste heated-up there was an explosion. No one was injured by the blast. However, over the next 12 hours or so a highly radioactive cloud drifted towards the north east, reaching some 350 km (about 220 miles) from the plant. It was a sparsely populated area, containing around 10,000 people. Following the explosion, people in the effected area “grew hysterical with fear with the incidence of unknown ‘mysterious’ diseases breaking out. Victims were seen with skin ‘sloughing off’ their faces, hands and other exposed parts of their bodies”. Due to the secrecy at the time, no one knows how many people died in the Kyshtym disaster. The area is still highly contaminated, more than 50 years later. The Mayak plant is still in operation today and is now one of the biggest nuclear facilities in the Russian Federation.

The Fukushima Daiichi plant has six reactors, and a further two that are still under construction. Spent fuel rods from the reactors are put in cooling pools (where it takes about five years for the heat and radioactivity to diminish to more managable levels). According to today’s Washington Post there are 1,760 tons of spent fuel stored at Fukushima Daiichi. The spent fuel is kept on site because it’s highly toxic and there’s not really anywhere else it can go (some countries re-cycle spent fuel; however, this is a very expensive process and it’s far cheaper to mine natural uranium, and turn it into reactor fuel). When the earthquake struck, Fukushima Daiichi reactors 4, 5 and 6 were not in operation, having been shut down for maintenance. However, as well as the problems with No.4′s cooling pond, reactors 5 and 6 have also suffered problems with water circulation in their cooling pools (today, TEPCO have said that the spent fuel pools of 5 and 6 are at around 84° celisus – normal temperature is 40°).

Not like Chernobyl??? Fukushima could make Chernobyl seem tame by comparison.

But let’s hope to God it doesn’t come to that.

Editing in: another interesting World Have Your Say programme, from the BBC’s World Service. Well worth a listen:

World Have Your Say – Radiation levels rise in Japan following third blast

Share
This entry was posted in Science and tagged , , , , , . Bookmark the permalink.