Wednesday, 23 March 2011

Nuclear Energy and Plate Tectonics

As the worlds attention has switched from Japans threefold disaster, perhaps it is time to reflect on the possibility of this disaster happening elsewhere, and to review the effects of the only other nuclear disaster besides the atomic bombs, to have been as threatening.

There have been many articles of late, speculating on the future of the worlds nuclear industry, and in reality, the likelihood of this disaster happening again is low. Nuclear remains one of the safest fuels even including the disaster at Chernobyl. This graphic from new scientist shows the deaths associated with each fuel type per 10 billion KwH of energy:

The impacts of coal, both in terms of extraction and the resultant deaths from poor air quality and pollution, are far greater than Nuclear, a recent study suggests that in the US alone, 13 200 people die every year through inhaling particulates largely produced by burning coal. In total, the UN estimates that 9000 people will have been killed by the chernobyl Meltdown. Pripyat is still evacuated, besides a few illegal re-settlers who returned to the area a few years after the 1986 catastrophe. The surprise fuel source in this graph is hydro, but the anomaly is explained by a year of severe flooding in China that caused a mass failure of dams.

So., does this mean nuclear is the way forwards? Probably not, but we do need to consider that the recent disasters in Japan have been disproportionately represented in the press. The lesson that needs to be drawn here, is that whatever we build, create or try to manage, we wont win against forces of this size. This earthquake knocked the axis of the earth off by 16cm, it moved an entire island 2.5m closer to the states, and created a wave detected thousands of miles away. Luckily, the Tsunami was not as powerful as the 2004 wave, and did not cause extensive damage outside of Japan. 

Also worth considering, is the likelihood of this happening again, as discussed in the New Scientist article distributed in class today, this was a disaster that would have been managed if only one of the disasters had occurred. Japan is no stranger to earthquakes, and widely used nuclear as it has virtually no fossil fuels of its own. So, how many other nuclear power stations are at risk? This fantastic map shows all earthquakes over 4.5 and the location of all reactors. The full map can be viewed here and is interactive:

It is clear that the potential risks are low for the vast majority of reactors, most are not in regions prone to large earthquakes. A blog from the Guardian highlights the risk as being connected to the age of the reactor, and there is some mileage in this. The older the reactor, the more degraded the concrete and casings, and the higher the possibility of the risk. Out of 442 active reactors, 60 were built before 1975, putting them at a higher risk of fault. Possibly of some concern, if we lived in tectonically active region, Hinckley point B1 was built in 1976 and B2 in 1978, in fact our newest power station is Sizewell B, completed in 1995, making it already 16 years old, in an industry where plants were originally predicted to last for forty years.

The map does show some potential threats. Japan is clearly the most active tectonically and with the largest volume of reactors, but there are others in a similar situation. This up close map of the US shows more detail on the links between tectonic activity in the states and reactor locations:

Those most at risk are in California Diablo Canyon and San Onofre, built to withstand a 7.5 and a 7 respectively, however, as little as two weeks ago, a new report highlighted they may not be as quake proof as first thought as a new fault system has been discovered near by. Diablo is built under half a mile from a new fault zone, and Onofre would be susceptible to both quakes and tsunami's both of which are common in California. The next "big one" is overdue and will of course, eventually come, does this mean we shouldn't build nuclear power plants? However, in terms of planning, it is probably not possible to plan for all these hazards, tsunamis hold potential to travel thousands of miles, so you cannot just manage your own coastline, you need to account for all others that could affect you! In terms of the Pacific, thats 21 countries that need to co-operate, manage and monitor not just earthquakes, but landslide risks, volcanoes and asteroids. No easy feat.
It does have to be pointed out, that magnitude 8 and over quakes occur very rarely, see last weeks New Scientist for a theory on linked or coupled mega quakes, and by no means, as far as I am aware, there are no risks of impending nuclear doom and Hinckley is certainly not at risk!

But, for your AS course, you do need to know about Chernobyl as it really represents worst case scenario for Nuclear, and with this type of energy experiencing a world wide renaissance, there has been much coverage and publication of images associated with the Chernobyl meltdown. Here are a few with some explanation:

Taken a few days after the diaster at reactor four, this image shows Chernobyl just before the decision was made to install the sarcophagus (See the Telegraph photo essay for more)

This photo is of a pig born near Chernobyl after the blast, the worst potential effects are to developing foetus' in the womb, and over 60 000 children experience problems associated with the metldown

What about the machinery used in the recovery efforts? It is too irradiated to use, and now sits in a field around 15 miles from the site as you need an NBC suit to go near it:

The problem of Chernobyl is ongoing, the sarcophagus was a hastily put together concrete tomb in 1986, that by 1988 already showed signs of structural stress, original predicted to last for fifty years, it was repaired in 2005, and is due to be replaced by the New Safe Confinement due for construction in 2013. The sarcophagus currently contains The sarcophagus locked in 200 tons of radioactive lava, 30 tons of highly contaminated dust and 16 tons of uranium and plutonium.In 1996 it was deemed impossible to repair the inside of the sarcophagus as radiation levels were estimated to be as high as 10,000 röntgens per hour (normal background radiation in cities is usually around 20-50 microröntgens per hour). The new structure should be more effective and last for 100 years:

Of course what a lot of the press has focused on for the last few days has been the risk of Fukushima releasing radiation into the atmosphere as Chernobyl did, and this radiation moving in the jet streams and coming down over other areas (like wales)

It is important that we do not allow the nuclear threat to overlook the far more significant disaster, the earthquake and tsunami. This image shows the degree of flooding is clearly shown in this before and after photograph of the Sendai region:

Besides the alteration to our axis, and the States-ward movement of Japan, the earthquake was pwoerful enough to shift the Whillans Ice Stream in Antarctica by half a metre, known as a slip event, it poses little risk, and it normally moves around a meter per day.

Here is a fact based round up of the disaster to date:

  • According to the Japanese foreign ministry, 128 countries and 33 international organizations have offered assistance as of Tuesday.
  • Economy Minister Kaoru Yosano told Reuters in an interview last week the total damage to the world's third-largest economy could exceed $250 billion, the equivalent of 2-3 percent of gross domestic product.
  • At least 14,722 buildings have been completely destroyed, the National Police Agency of Japan said on Tuesday.
  • At least 760,000 households in 10 prefectures were without running water as of Tuesday, the Health Ministry said, down from
  • A total of 9,199 people were confirmed dead by Japan's National Police Agency as of 1400 GMT on Tuesday, while 13,786 were reported missing
However, one of the worst damaged roads has already been repaired:

This really represents the difference in levels of development and recovery, Japan's earthquake was over 100 times more powerful than Haiti, yet in Haiti less than 5% of the rubble has been cleared and only 5-10% of the houses needed have been built. The situation is still dire, with much of the population in increasingly unsafe and dangerous refugee camps:

This photo was taken in January of this year, lets hope that it improves soon:


  1. Great post!
    If you wanted an interesting debate you might say that Chernobyl was the biggest contributor to the fall of the USSR, thus reducing the chance of a nuclear war, ironically making the world much safer. It's worth mentioning that many of the higher numbers for the disaster assume all cancer was caused by the accident. As the area around it was one of the poorest areas of an badly run communist state, that seems unlikely.

  2. Hi Zeonglow! interesting perspective, I hadnt thought of it in those terms, but what a fantastic synoptic link between the nuclear industry and world safety!