Long-lived radioactive wastes are not only produced in nuclear power generation and nuclear weapons programmes. The largest inventory is in the form of spent reactor fuel – 130,000t is stored at around 400 facilities worldwide, and this is growing at the rate of 10,000t/year – but in addition, medical isotope production, medicine, research and industry all produce waste that has to be isolated for up to 100,000 years.

It is the responsibility of current generations benefiting from nuclear technology to manage this waste.

Another hazard that may arise in storing nuclear materials is that of security. Highly enriched uranium and plutonium are fissile materials, which can be used to make nuclear explosives. This problem is being increased by the disarmament currently underway in Russia and the USA. Hundreds of tonnes of plutonium and thousands of tonnes of highly enriched uranium will become available for other purposes as these surplus weapons are dismantled.

Society must face the challenge of ensuring that the weapons-grade materials are converted into forms that are unsuitable for use in bombs and are safeguarded permanently from misuse by states or by terrorist groups. Terrorists could, it is feared, also spread radioactive materials using conventional explosives in a so-called “dirty bomb”. The aim must therefore be to safeguard all sensitive nuclear materials by making them inaccessible to such groups.

The challenge is to maintain safety and security by permanently isolating the long-lived radioactive materials. This isolation can be achieved for long periods by building, maintaining and guarding strong and secure surface storage facilities. However, this leaves a legacy to future generations.

The ideal solution would be to remove the material permanently from Earth (such as by ejection into space) or to change it to a less harmful form. The former option has been considered periodically since the 1970s and it has always been found to be too risky and too costly. Transforming long-lived radionuclides to shorter-lived ones is possible by transmutation in a reactor or a particle accelerator. This has also been studied for 30 years, and the consensus is that it is a complex and immensely costly process. It cannot get rid of many of the more problematic radionuclides, nor does it do away with the need for geological disposal.

Today, the single solution that is judged by scientists as being capable of removing the hazards of radioactive waste without placing undue burdens on future generations is deep geological disposal. This view is enshrined in the legislation of countries such as the USA, Sweden, Finland, Japan and Switzerland and is the chosen approach in many others. Although some countries have re-opened the question of whether real alternatives are available, no one has developed a scientifically feasible, sustainable and ethically justifiable alternative.

Deep disposal programmes

Virtually every waste disposal programme in the world has experienced delays – often very significant delays – in its schedule for disposal of spent nuclear fuel or high level waste. The USA had the earliest proposed operational dates for a geological repository, partly because it planned immediate disposal, rather than a cooling period of 30-50 years. The Nuclear Waste Policy Act of 1982 set out a strategy leading to geological disposal. Following years of field work and expenditure of several billion dollars, early this year the US president approved the Yucca Mountain site for a repository. The Department of Energy aims at disposal by 2010.

There are bound to be legal delays, but the USA may still be the lead nation, although two countries are following close behind. In Sweden, an early decision to close down nuclear power meant that a definite final waste inventory could be planned. Finland has successfully nominated a site for spent fuel disposal, so that there could be three operating repositories by around 2020.

In other countries, such as Japan and Switzerland, there is no need for deep disposal before about 2050. In others, such as the UK, Spain, Canada and the Netherlands, decisions on geological disposal are wide open and implementation, if it happens, may be a hundred years off.

All of these countries mentioned have run waste disposal research programmes of various intensities and for many years. Other countries, such as Taiwan and South Korea, that rely strongly on nuclear power have just begun disposal studies. Numerous smaller countries with limited nuclear facilities will have problems finding sufficient resources to develop appropriately scaled national R&D programmes.

A repository in every country?

Most countries should be able to find suitable disposal sites. Repository designs are flexible and the degree of sophistication of the engineered barriers can be altered depending on the varying geological environments. However, the availability of a worldwide choice of regions would make it easier to choose sites in stable, simple geological and hydrogeological settings so that the uncertainties in long-term safety assessments are reduced. The Pangea project performed studies to identify such regions and investigate their safety performance (see Pangea Technical Report PTR-01-01: Siting a High Isolation Radioactive Waste Repository – Technical Approach to Identification of Potentially Suitable Regions Worldwide by J H Black and N A Chapman).

Even if a national repository is technically feasible, it may still be ruled out by economics. A deep geological facility for long-lived radioactive wastes can cost several billion dollars, no matter how small the volume of wastes that need to be disposed, and it is inconceivable that each country with such wastes will be able to provide adequate resources.

Some countries have only a single reactor; some have no power reactors but still produce long-lived wastes from medical research and industry. For such countries, shared geological repositories are essential.

For other countries, complex geology, intense land use, or economic optimisation will justify pursuing international options, even if national disposal were possible. Switzerland, Belgium, Hungary, Slovakia and Taiwan are among the countries that have a “dual track” approach, in which international options are kept open while a national option is also being considered.

The argument that geological disposal is the only sustainable solution to managing long-lived wastes, because it does not pass on problems to future generations who may have neither the resources nor the capability to handle them, applies in any country and to any size of programme. It is perhaps an even more cogent argument for those countries, including several European countries with small nuclear power programmes, where pressure on resources is already evident.

It is important for the nuclear industry, and for the wider interests of environmental safety and nuclear security, that the radioactive waste management community demonstrates that waste from “small users” and countries with limited resources can be properly managed. Providing such solutions will also give the smaller programmes the confidence to make best use of their nuclear power facilities and to have greater flexibility in choosing future power generation options. In short, there should not be a two-tier system for disposal of hazardous wastes, and hence for the application of nuclear technologies. It is in everyone’s best interests that equivalent technologies are available on equivalent time scales to all those countries that need them.

In recent years there has been an active debate on shared repositories. These are labelled “international” or “multinational”, with the latter term preferred by those who do not wish to presuppose a necessity for overarching international controls. The term “regional” is used to describe repositories shared by geographically close countries. Shared repositories can have definite advantages, as described below.

Sharing the benefits

In the area of safety, in particular long-term safety, there is no difference in principle between a multinational repository and a national project. There is no need to tighten the rigorous safety requirements set for national disposal facilities and it would not be ethical to seek regions or countries where less stringent measures could be acceptable: both must provide the same internationally agreed, high level of safety over very long timescales.

The technical challenges in implementing a safe international repository are equivalent to those in leading national programmes. Safety depends upon the complexity of the disposal system and especially on the predictability in spatial and temporal terms of the geological environment. The long-term containment of waste materials will be easier to achieve and to demonstrate in a simple, stable geological environment chosen without the restrictions imposed by political boundaries.

Issues concerning operational safety are also relevant – in particular to the host state. The optimum situation is when the host country has nuclear technology capabilities and would itself be capable of implementing a safe repository. Otherwise, know-how must be transferred from others.

As regards security, international facilities may have advantages, even compared with the inherent safeguard advantages of a national deep repository.

• Many countries with spent fuel may not have repositories soon, or ever.

• Host countries can be identified that have good safeguards.

• Control becomes even more international than through the current IAEA regime.

• Repository sites can be selected in regions that are extremely remote and more amenable to surveillance.

The supreme importance of ensuring full safeguards for fissile materials may be one of the more powerful arguments for a potential repository host state. An international repository in a country acceptable to all nuclear weapons states could help the political process of reducing nuclear weapons. It could also provide a commercial source of financing to address non-proliferation.

The issue of environmental protection would become simpler if there were a worldwide choice for a disposal site. Nuclear power can only help limit CO2 emissions if there is cost-effective disposal. An international repository can contribute here. Nationally, small, crowded or geologically complex countries with limited sites find it difficult to implement any new and large industrial project. A host country with remote areas far from the public may find a less contentious site. There is a definite potential for using a well-funded repository implementation project as a vehicle for improving facilities and conditions in inhospitable areas.

Nevertheless, a major international repository, with its necessary transport and site infrastructure, will obviously have a significant environmental impact – comparable perhaps to a mining project. To compensate for this asymmetric burdening of host and client, the host would receive appropriate benefits.

From an economics point of view, shared repositories are attractive. Deep geological repositories have life-cycle costs in the billions of dollars, even for small countries with low projected waste volumes. The Swiss estimate of life-cycle costs for disposing of HLW or spent fuel from a 120GWe nuclear programme is around $3 billion, for example. A large part of the costs of any deep repository is fixed independently of the inventory, since it covers exploration, shaft sinking, infrastructure and complex permitting and licensing procedures. The marginal costs of excavating more disposal volume underground are relatively small, so savings are possible if small countries combine their efforts.

Savings are equally possible if a large disposal programme were to accept wastes from foreign sources – and a country accepting foreign wastes would clearly receive enormous direct economic benefits.

There would also be financial benefits for the countries paying for wastes to be disposed abroad. Economies of scale allow lower unit costs (and excellent geological conditions can obviate the need for very expensive engineered barriers).

For society in general, it is better not to use resources to duplicate expensive technical work in different countries.

Obtaining sufficient public acceptance will be a major challenge. It could only be achieved in the host country if the economic and infrastructure benefits are very clear, and the safety, security, environmental and ethical aspects are clearly seen to be taken extremely seriously by all parties. A serious host country will not allow itself to be “bought”; there must be also a clear perception that the host country is undertaking a service which helps less advantaged countries fulfil their moral responsibilities for their waste in an ethical manner. A serious customer nation will insist on being assured that the highest standards of safety and environmental protection are applied to any facility accepting its waste. Switzerland, for example, has built such safeguards into its new Nuclear Law.

The ethical principles espoused by the waste management community concern, among other matters, intragenerational and inter-generational equity. This involves adequate protection of all persons and of the environment now and in the future, irrespective of national boundaries. Clearly, an international repository must and could be implemented in accord with such principles. In particular, the level of safety required for populations around any repository cannot be a function of the facility location.

Notwithstanding these indisputably positive arguments, public acceptance for accepting foreign wastes will be extremely difficult to achieve in any potential host country. Public attitudes towards shared repositories may be changing, however. Recent results suggest that supporters in Europe of regional repositories, although still in the minority, are increasing in numbers.

Although there are few technical or economic stumbling blocks, it has been politically impossible for some countries to support a joint repository, especially if they were to be considered as a potential host. In some countries, such as Sweden, Finland and France, legislation ensures that foreign waste cannot be imported for disposal and in others – for example Australia – import has been explicitly stated to be against government policy. However, in international agencies such as the IAEA and the European Commission, it is increasingly acknowledged that shared disposal facilities are inevitable. Some countries, most notably Russia, are openly considering plans for importing waste for storage and possibly disposal.

National programme issues

Countries with repository programmes may be afraid that international programmes will mean they have to accept foreign waste – by choice or compulsion. In Sweden, for example, opponents of national programmes have used such arguments, despite the existing Swedish legislation ruling out waste import.

A further concern in some national programmes is that the prospect of a politically easier or economically better external solution may slow national development. But this argument is irrelevant in countries where national geological repository preparations are not in any case being made. It is also not very important in those countries that have chosen a “dual track” strategy, investigating both national and international disposal options.

For those countries fully committed to national disposal, these concerns are very real. They can, however, be countered by their firmly emphasising the national strategy, without denying the needs of others for shared solutions.

A national programme that has decided not to develop a deep geological repository of its own has a limited range of waste management options available to it. It can store its wastes indefinitely within its own borders, or it can store its wastes at home or abroad until an international solution is available. If the latter, it must either participate in the international development or wait for a disposal service to be offered.

Will the political leadership in any country support any suggestion of hosting a shared facility, knowing that this will inevitably raise strong opposition? Here lies the impasse in developing an international site and history does not give much cause for optimism. The UK and France did accept foreign wastes for disposal, but the policies were reversed to reduce opposition to national nuclear reprocessing industries. In some countries where the proposal to host a repository began to be debated, politicians rushed to express disapproval, despite significant support in scientific and business circles. In Russia, one of the few countries where government agencies support the import of waste for storage and possible disposal, public opposition has grown. In some circles there has even been strong opposition by national programmes to the issue of multinational repositories being a subject for discussion.

A lost cause?

Is it a lost cause to advocate international or regional repositories? Even those countries or organisations that have opposed opening the issue now acknowledge that shared disposal must come, for safety, environmental and economic reasons. The commonly heard reservation is that one or several national deep geological repositories must first “show the way”. In practice national facilities will, in any case, come first. But preparations for international disposal should start now. Technical, public and political confidence in the use of nuclear technologies in small countries depends upon having safe multinational disposal routes available. Where might these be?

The prime candidate at present is Russia. The advantage for Russia, apart from the obvious economic gains, is that resources would become available for urgently required clean-up programmes. Other countries do not favour Russia’s proposals, mainly because they doubt the authorities would implement environmentally suitable solutions to the highest international standards. In the USA, whose assent is needed for any international repository scheme, there are further political hurdles preventing a Russian solution. With goodwill and a concerted action programme, however, an acceptable Russian solution could be possible. Extreme measures, such as effectively ceding a part of their territory to international control may be needed. The IAEA could play a key role in such an approach; its original charter shows that such concepts are not new.

A regional solution may also become popular, for example in East Asia or Europe. In fact, although some individual members of the current EU are opposed to shared repositories, officials in Brussels recognise that this could be a sensible approach. The planned increase in EU membership involves a number of candidate countries that would be obvious partners in disposal projects. Existing members would do well to support such initiatives technically and politically.

The new Arius association, whose mission is the promotion of international and regional facilities, has submitted an expression of interest to the European Commission in co-ordinated studies aimed at investigating the potential for regional repositories in Europe.

If or when geological disposal becomes a widespread technology, past studies may be picked up to allow suitable countries to host a repository. The Pangea project identified suitable areas in Australia, Southern Africa, South America and China. Of these, only Australia was studied in any depth, and the technical findings made the case for safe and environmentally friendly disposal clear. Politicians in such countries will, however, hardly promote such proposals unless there is clear support and encouragement from the developed nuclear nations.

The way ahead: Arius

In February 2002, a small group of organisations from five countries inaugurated a new association to support the concept of sharing facilities for storage and disposal of all types of long-lived radioactive wastes. The new body is called Arius (Association for Regional and International Underground Storage).

A key objective is to explore ways of making provision for shared storage and disposal facilities for smaller users, who may not wish to – or may not have the resources to – develop facilities of their own. Consequently, the initial membership of the Arius association is predominantly from countries with smaller nuclear programmes, although it also includes industrial organisations that are interested in promoting the international disposal concept. The members of Arius in its first year are from Belgium, Bulgaria, Hungary, Italy, Japan and Switzerland.

As Arius develops, it plans to undertake a number of studies that are aimed at answering some of the principal questions surrounding international solutions. These include:

• Feasibility of regional storage of long-lived waste in Europe.

• Issues affecting transport to international storage facilities.

• Feasibility of regional repositories in Europe. An expression of interest for a European Pilot Study for Regional Repositories (EPSRR) has been submitted to the EC.

• Feasibility of international repositories outside Europe.

• Treaties, agreements and liabilities affecting the import/export of waste.

• Regulatory and licensing processes for international facilities.

• Economics of shared storage and disposal facilities.

• Public attitudes to the import and export of wastes.

The key research components of Stage 1 of the proposed EPSRR project are:

• Radiological safety implications of shared facilities – developing a basic safety concept for a multi-functional repository that could accept a wide range of long-lived wastes and studying transport issues.

• Social factors – evaluating data nationally and Europe-wide and polling.

• Economic aspects – comparing costs and studying models for economic management of shared repositories.

• Legal and political – examining boundary conditions that would control the feasibility of building multinational repositories in Europe.

The output of the Stage 1 feasibility study will be a range of options for developing one or more shared repositories, together with an implementation proposal to allow the enlarged EU to decide whether to move forward.

Stage 2 of the project would begin with a period of consultation with all European countries that choose to participate and a parallel research exercise to identify regional siting possibilities, potentially leading to consideration of specific locations. This stage of the project will involve mainly scientific research studies, including:

• Considering specific European geological environments in interested member states that may be suitable for a multi-purpose repository.

• Developing formation-specific and environment-specific safety concepts for such repositories.

• Applying multi-attribute analysis techniques to compare siting environments, locations and repository design concepts from technical, safety and social viewpoints.