The development and welfare of modern societies depend to a large extent upon the contribution of technology and industrial processes, such as the generation and widespread use of electricity. These processes are, in general, associated with the production of wastes, some of which are unavoidable, unrecyclable and hazardous. Such wastes require careful management to ensure adequate protection of humans and the environment. The timescales over which such protection is required can extend, in the case of wastes containing toxic chemical elements or long-lived radioactive isotopes, well beyond the lifespans of current or forthcoming generations, i.e., many thousands of years into the future. Hence there is an ethical imperative to care about future generations and to act in such a way as to preserve, as much as possible, their options to enjoy and benefit from the Earths resources. Such a concern for the protection of human health and the environment in a developing world has been illustrated by the concept of "sustainable development" put forward by the World Commission on Environment and Development, "the Brundtland Commission", in 1987 . This concept, which is principally an ethical one, was defined as "satisfying the needs of the present, without compromising the ability of future generations to meet their own needs".
The concept of "sustainable development" was chosen as the main theme of the United Nations Conference on Environment and Development in Rio de Janeiro in 1992, and was therefore extensively discussed. It is appropriate that the principles of this concept be applied to complex environmental issues such as the ones resulting from the production of potentially harmful wastes. Current environmental protection policies are increasingly concerned with issues of a global nature related to long-term consequences of, for example, ozone depletion and climate changes. In this context, an evolving environmental consciousness, coupled with the emergence of strong ethical concerns, indicate the importance attached to morally correct human conduct . This trend should contribute to the adoption of public policies integrating both technical and ethical considerations to maximise the benefits and limit the potential adverse effects of industrial development now and in the future. It is therefore welcome that ethical issues are currently being integrated into the environmental debate.
This debate, however, is affected by the judgmental nature of ethical values which are themselves influenced by the professional, cultural and social backgrounds of the participants. As a result, a balanced and objective understanding of environmental or health impacts is often difficult to separate from the interests of those involved in the debate, particularly those who may be directly affected and those who have an obvious interest. It is, therefore, of some importance that the discussion of ethical and other considerations be approached with an open mind and involve a broad spectrum of public representatives in order to create the conditions for a sound analysis of all the relevant aspects. This Collective Opinion is intended to contribute to that analysis by presenting the view of the national representatives comprising the Radioactive Waste Management Committee of NEA, having considered carefully the results of the Workshop referred to above.
In the management of wastes having a long-term potential for harm, interest focusses on two classes of ethical concerns.
The first is the achievement of "intergenerational equity" by choosing technologies and strategies which minimize the resource and risk burdens passed to future generations by the current generations which produce the wastes. It is a fact of life that each generation leaves a heritage to posterity, involving a mix of burdens and benefits, and that todays decisions may foreclose options or open new horizons for the future. This is unavoidable, but our actions and decisions will be more acceptable if appropriate degrees of equity or justice are respected, and we do not unduly restrict the freedom of choice of future generations. In the case of nuclear energy production and the management of radioactive wastes, as with various other aspects of industrial activity, the balance between the benefits which are enjoyed by present and future generations through sustained technolo-gical development, and the liabilities which may be imposed on future gene-rations over a long period, must be carefully scrutinized. As radioactive wastes already exist, as a result of past and current activities, the issue of waste management has to be faced regardless of the future of nuclear energy. The objective is to manage the wastes in such a way that potential future impacts are kept at a level that is acceptable both ethically and in terms of safety. In the context of financial provisions for future liabilities there are real concerns whether the value of an invested monetary provision will compensate a society faced, many generations later, with the physical task which the provision was intended to fund. The preferred strategy is to accomplish key tasks of technology development and repository siting within the timescale of current generations.
The second concern is the achievement of "intragenerational equity" and in particular an ethical approach to the handling, within current generations, of questions of resource allocation and of public involvement in the decision-making process. The form of this process is shaped to some extent by national institutions and political factors, and it was not therefore included in the NEA Workshop background papers, but the need for public involvement was emphasized in the workshop discussions and its importance in making key decisions, such as the timing of waste disposal actions, is clear. When considering resource allocation, risks from radioactive wastes must be kept in perspective with competing projects in the area of human health and environmental protection. Also relevant in this context is the consideration of equity and fairness for communities which are judged to be affected by the construction and operation of a centralised national facility such as a geological repository for long-lived wastes.
Consideration of these concerns leads to a set of principles to be used as a guide in making ethical choices about waste management strategy: