What’s so difficult about dealing with radioactive waste?
The short answer is that scientifically and technologically it is very well understood, but the societal aspects are seemingly intractable at first sight, particularly with respect to the higher activity, more hazardous radioactive wastes – (almost) nobody wants it in their backyard! Even in the few countries which are near to implementing solutions for these difficult wastes, it has taken decades to get to that position, which has provided long-term careers for many of those involved, including the author of this article!
For example, Finland, which is nearest to having a geological disposal facility in operation, has just celebrated its 40th anniversary since taking its “decision-in-principle” to dispose of its spent nuclear fuel in the Finnish bedrock. Finland is also the country which has stuck most closely to its original programme, set out originally in 1978, always maintaining that the first disposal will take place in the 2020s. It has served as a useful benchmark and exemplar of how to manage relationships between the implementor, regulators, local communities and political decision makers.
This article will provide a basic overview of radioactive waste issues, what long-term management options have been considered, how different countries are dealing with it and what is happening at the international level. We will keep the science to a necessary minimum, explaining why things are done the way they are.
Policies and strategies in radioactive waste
Whether you are in favour or against nuclear power, the simple fact is that radioactive waste exists! Even if the nuclear industry closed down tomorrow, radioactive waste will continue to be generated for many years to come. Moreover, it is internationally recognised that there is a need for nations embarking on a new nuclear programme to have policies and strategies for dealing with operational and decommissioning radioactive wastes and spent nuclear fuel at the earliest stages. These policies and strategies are most often based on the guidance of the International Atomic Energy Agency (IAEA) which brings together practitioners, such as myself and colleagues, from across the globe to develop such advice and transfer knowledge.
Implementation of these policies and strategies is usually the responsibility of a national Waste Management Organisation (WMO). Most countries with nuclear programmes have such organisations and personal experience demonstrates that developing relationships between WMO’s and sharing best practices is an important enabler for progress. Such best practice covers scientific, technical, societal and financial (“polluter pays”) aspects.
Origins
So where does radioactive waste come from? In summary, from nuclear power plants and associated fuel cycle facilities, research and development activities, and industrial and medical uses of radioactive material. Nuclear power is, of course, the biggest contributor but there is also another group of radioactive materials which a country may need to consider and that is naturally occurring radioactive materials, or NORM. These materials arise in the natural environment and are present in substances such as coal ash, certain mineral ores, and oil and gas exploration wastes. We will discuss these more in a further article.
Nuclear industry
The World Nuclear Association reports that there are about 440 commercial nuclear power reactors in operation around the world supplying about 10% of its electricity; and there are a further 220 smaller, research reactors. About 200 commercial and prototype reactors, and 500 research reactors, plus several fuel cycle facilities are shut down and undergoing decommissioning. About 60 new reactors are under construction, with a further 110 being planned. In addition, there are nuclear-powered ships and submarines, and nuclear weapons production facilities. As well as generating electricity, enabling nuclear research and medical isotope production, and providing marine propulsion and defence capability, they all have one thing in common: they produce liquid, gaseous and solid radioactive wastes.
At very low levels of impact, these wastes may be discharged into the environment without cause for concern. At higher activities, gaseous and liquid wastes may be treated and converted to a solid form, ready for disposal.
Dealing with radioactive waste
If we look at the solid radioactive wastes, these are usually classed as very low level, low level, intermediate level and high level; in addition, there is also spent nuclear fuel which can be regarded as a waste or a resource, depending on the policies and practices of the country concerned. Unfortunately, these classifications are not the same across the globe, but for the purposes here, in very broad terms, they can be grouped into lower or higher-activity wastes.
Again in broad terms, when it comes to disposing of suitably conditioned radioactive waste, the lower activity wastes can be disposed of in “near-surface” repositories and higher activity wastes in deep geological disposal facilities. By near surface, we usually mean engineered facilities at or near the surface, or at most a few tens of metres below, and here there are very many examples of such repositories in operation around the world. In general terms, the radioactivity levels in these facilities will decay to normal background levels in about 300 years
Deep geological disposal means putting the waste more than several hundred metres underground either in mined facilities or deep boreholes. This solution applies to those wastes which will remain hazardous for many hundreds of thousands of years such as spent nuclear fuel, vitrified high-level waste from spent fuel reprocessing, plutonium-contai wastes and other long-lived wastes (with half-lives greater than 30 years).
Both of these concepts have been studied in a number of countries for many years. Mined facilities are now being constructed in Finland, Sweden and France, each of which appears to be successfully addressing the societal issues associated with consent-based siting. The deep borehole concept remains to be adopted as the preferred solution but several countries are considering it. Many other countries have adopted policies for deep disposal either in national or multinational facilities and are at various stages of selecting suitable sites.
So What is the Answer?
But why “disposal”? Why not long-term storage, disposing at sea, firing it into space, disposing in ice-caps, …? Can it be “dumped” on so-called poorer nations, or sent to Antarctica? Long-term storage, in effect, just passes on the problem to future generations; international treaties, safety considerations and cost prevent the more esoteric options from being adopted.
In summary, all countries which have looked at the various options in detail conclude that radioactive waste should be disposed of and not indefinitely stored, with geological disposal being seen as the right answer for higher-activity wastes.
As a number of countries are showing, it is possible to implement disposal solutions. The science, technology and resultant safety are well understood, and the societal aspects are able to be addressed with the right approach.
Countries new to nuclear, or those with NORM issues, will be developing their own policies and strategies for dealing with radioactive waste. A key message is that the experiences of other countries may help them develop and implement these successfully.
Written by John Mathieson
John Mathieson has some 47 years’ experience in the nuclear industry, primarily involving the areas of radioactive waste management and decommissioning. John worked 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, including help establish a number of Waste Management Organisations.
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, and is a Board Director and Secretary of Waste Management Symposia Inc. which runs the annual Waste Management conference in Phoenix, USA.
