What’s so difficult about dealing with radioactive waste?
Last month we gave an introduction to the issues of dealing with radioactive waste. We looked at where it came from and gave a brief overview of the various options for the longer lived varieties, which includes spent nuclear fuel and high level waste from the reprocessing of spent fuel. This article explores those options in more detail and explains why they may have been discounted in favour of geological disposal.
In 2003 the British Government set up the independent Committee on Radioactive Waste Management (CoRWM) to advise on the options for dealing with the country’s higher active radioactive waste. They started with a “blank sheet” and drew up their long list of options.
These included indefinite storage, variations of disposal on land, injection of liquid wastes into rock strata (which has been practiced in Russia), disposal at sea (which was the practice for some higher active wastes until this was banned under the London “Dumping” Convention), sub-seabed disposal, disposal in ice-sheets (with the heat of the waste sinking it to the bottom of the ice), disposal in subduction zones (i.e. where the Earth’s tectonic plates collide and the waste would be carried into the Earth’s mantle), disposal in space or propelled into the sun, and dilution and dispersal into the environment. (Note the distinction between “storage”, which is emplacement with the intention to retrieve, and “disposal”, which is emplacement without the intention to retrieve).
Geological Nuclear Disposal
The CoRWM eventually recommended, inter alia, to the British Government that geological disposal was the “best available option” for dealing with higher activity waste. More recently, the US Blue Ribbon Commission on America’s Nuclear Future also undertook a study into various options and in 2012 recommended that the US develop a deep geological facility. These conclusions also concur with the views of the International Atomic Energy Agency (IAEA), the European Union and the Nuclear Energy Agency of the Organisation of Economic Co-operation and Development (NEA). Indeed, virtually all countries which have highly active waste have selected geological disposal as their policy.
Selecting the policy is one thing but implementing it is another and we will look at the global status of that in the future.
So, what’s the problem with the other options? Notwithstanding the public acceptance aspects, the issues are:
- Storage is just that! By definition it is an interim solution. Indefinite storage would require waste to be retrieved, repackaged and re-stored. This would pose undue financial, environmental, security and health burdens on future generations, and requires stable societies for thousands of years to be entrusted to look after it.
- Injection of liquid waste into rocks is technically feasible with the right geological environment, as the Russians have shown, but there is no clear proof of concept and there are significant health, safety, security and environmental risks.
- Disposal at sea is now banned, as mentioned above, and also breaches one of the fundamental principles of waste management, dealing with it within our own borders.
- Sub-seabed disposal also breaches international law and there are risks to future generations depending on future climate change scenarios, plus environmental concerns.
- Disposal within ice sheets is actually a patented idea! However there is no proof of concept and environmental and safety concerns dominate, particularly with global warming and the melting of ice caps.
- Subduction zone disposal, again, is just theoretical and breaches international treaties. Moreover, there is even the risk of the waste reappearing through volcanic activity!
- Disposal in space, again, would contravene international treaties and be technically challenging requiring many space missions, none of which could be allowed to fail. There is the further risk of the waste returning to Earth if it did not adopt the correct trajectory. The costs would be prohibitive and would far outweigh any benefit.
- Dilution and dispersal has little going for it as it would mean discharging the radioactivity straight into the environment. This would breach international treaties and would be quite risky.
So having concluded that disposal is the right solution, where should the facilities be?
In the next article we will look at the international aspects of disposal and why we can't send it to Antarctica or a “third world” country.
About the Author
John Mathieson is a non legal technical advisor on nuclear energy related issues in a number of key international markets.
He has some 36 years’ experience in the nuclear industry, primarily involving the areas of radioactive waste management and decommissioning. John works with the International Atomic Energy Agency and the European Commission, participating in expert missions, technical meetings and working groups. He has worked on projects assisting many overseas governments to develop financing, decommissioning and radioactive waste management strategies and infrastructures. John Mathieson has a BSc (Hons) in Physics and an MSc in Radiation and Environmental Protection from the University of Surrey.
He is a Member of the Society for Radiological Protection, a Member of the American Nuclear Society, and is a Board Director and Secretary of Waste Management Symposia Inc. which runs the annual Waste Management conference in Phoenix, USA.