When spent fuel is removed from the reactor core, it is a pulsating mass of radioactivity, containing uranium, plutonium, cesium, strontium, technetium and neptunium among other elements. If unshielded, it would kill a person standing three feet away in seconds. Even after decades of radioactive decay, a few minutes’ unshielded exposure could deliver a lethal dose.
While the spent fuel only accounts for around three per cent of the volume of all waste from a nuclear facility, it holds 95 per cent of the radioactivity and is deemed to be high-level waste. Certain radioactive elements, such as plutonium, will remain hazardous to humans and other living beings for hundreds of thousands of years. Each 1000-megawatt nuclear power reactor produces about 30 metric tonnes of such high-level waste a year.
After being removed from the reactor, the spent fuel rods are stored in pools at the nuclear facility to cool down. The spent fuel rods remain hot because fission energy continues to be released as the radioactivity decays, so the pools contain boric acid to slow the process down. It should spend between 6-18 months cooling before being removed to a permanent disposal site. As yet none has been permanently disposed of, as no-one knows how best to safely store such dangerous material, or where. A consequence of this is that many nuclear facilities have had to enlarge their storage pools to accommodate all the high level waste produced since they started generating electricity.
As fuel pools were not designed for more than temporary storage, there are many hazards associated with them. According to the Nuclear Information Resource Service, these include the potential for loss of coolant, which could result in spontaneous combustion of the fuel, or in some circumstances, nuclear meltdown of the pool.
Another distinct possibility is that facility managers lose track of how much waste they have and it simply goes missing. In 2002, a decade after the Dominion reactor in Connecticut, was decommissioned; the US Nuclear Regulatory Commission was informed that two spent fuel rods were missing. A subsequent inquiry concluded that the fuel had most likely been cut into segments and sent to a low-level radioactive waste dump, which would afford inadequate protection against high-level waste. The operator was fined around $300,000.
If the spent fuel is reprocessed to rescue the plutonium, then stockpiles of plutonium build up. Again, the security risk is all too apparent. In 2003-4 British Nuclear Group admitted that the reprocessing facility’s fuel inventory didn’t add up and that 30 kilograms of plutonium could not be traced. ‘Some years there is an apparent gain, some years there is an apparent loss,’ a BNG spokeswoman said at the time of the inventory, which has been kept since 1970.
Guidelines issued by the International Atomic Energy Agency (IAEA) say that material unaccounted for must not exceed three per cent of the amount that is processed. 30 kilograms would represent around 0.1 per cent of that amount at Sellafield. That means around 900kg of plutonium could go missing before the world’s nuclear regulator became alarmed. Yet it takes only around 10kg of plutonium to make a bomb. According to the Oxford Research Group, a ‘dirty bomb’ of such magnitude would devastate a city centre.
The Committee of Radioactive Waste Management (CoRWM) has recently said that these stockpiles of waste should be stored underground. In the process, it ruled out such options as putting it on the ocean floor or flying it into the sun. CoRWM is well aware that any chosen site will meet a high level of public opposition. In America in 1987, Yucca mountain in Nevada was designated as the final repository for the 700,000 tonnes of nuclear waste accumulated from their civil nuclear power programme. It has been the subject of a legal wrangle ever since. Recently, the US Environment Protection Agency was defeated in court for ‘arbitrarily’ guaranteeing the waste would be safe for 10,000 years. The US National Academy of Sciences told the court the figure should be 300,000 years. In Sweden, by comparison, a guarantee of one million years is demanded.
Once a site has been identified, the waste must be delivered by road or rail – another hazardous journey. In a study for Greenpeace, nuclear expert John Large, of Large & Associates, concluded a terrorist attack on a routine transport of nuclear waste in the UK could spread radiation over 100 kilometres. As the train routes pass through several large towns and cities, such as London, Bristol and Edinburgh, tens of thousands of people could be exposed to radiation.
Yet local authorities along the nuclear road and rail routes are not required to have in place any emergency plans, or a strategy of how to inform the public of what best to do in the event of accident or attack.
Once at the chosen site, the fuel will be buried some 500 metres below ground in specially – prepared flasks that can withstand corrosion. Considering how long the waste will remain radioactive, an element of wishful thinking needs to take place to believe this can be successfully achieved. Five thousand years ago the English Channel didn’t exist. 10,000 years ago a volcano erupted near Yucca mountain. Geology changes in ways that can’t be predicted. The climate is changing; sea levels are set to rise. To think this is a problem we can leave to future generations to resolve is not only morally repugnant, but presupposes they will be in a position to do so. A fuel crisis is looming now. It is a distinct possibility that future generations could find themselves with mountains of radioactive waste to dispose of and little energy with which to achieve the job. Any renaissance in the nuclear industry will simply compound the problem we face now.
Another area yet to be decided on is whether the repository should be sealed or left accessible for future generations to monitor. There is an inherent security risk associated with doing this. Who is going to guard the repository and its contents? It is all too evident what happens when a country becomes politically and economically unstable from what is known about Russia, where plutonium routinely goes missing.
In 1997, former Russian National Security Adviser General Alexander Lebed stated on American television that the Russian military had lost track of more than 100 suitcase-sized nuclear bombs, any one of which could kill up to 100,000 people. With resource wars over oil, gas and uranium a distinct possibility, no nation in the global economy can guarantee economic stability, at which point the stockpiles of nuclear waste would become vulnerable to theft.
Despite all this uncertainty, a price has been put on the cost of disposing of the waste in the UK. This has risen from an original figure of £52 billion to around £70 billion in the past few years. In America consumers have been charged one cent per kilowatt-hour of electricity used to pay for the eventual disposal of nuclear power waste. This has raised in the region of $18 billion, of which $6 billion has already been spent investigating the suitability of Yucca mountain as a final repository.
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This article first appeared in the Ecologist June 2006