Most countries have experienced difficulties in finding acceptable sites for the storage or final disposal of high level radioactive waste. It seems highly unlikely that the UK will implement a policy of deep underground geological disposal for many years. As a result, there is an opportunity to consider whether, given the present pace of technological development, it is likely that an alternative solution could be found within the next 100-1000 years, which would be preferable on ethical grounds.

Some possibilities are:

• Transmutation of high level waste to short-lived isotopes.

• Advances in medicine that would reduce or eliminate the risk of radiation-induced cancers.

• Transfer of high level waste to uninhabitable regions of the solar system.

The use of monitorable, retrievable, surface storage (MRSS) with a design life of, say, 2000 years would provide the necessary time for one or other of these developments. There is, of course, the possibility that within this time frame the world order would collapse completely collapse due to some catastrophe (major nuclear war or an asteroid strike), leaving a small population eking out an existence at survival level. In that situation, the hazard presented by high level waste would appear trivial.

The merit of MRSS as an interim solution is also dependent to some extent on the likelihood of the need for a large re-expansion of nuclear power within the next 50-300 years, in order to meet the demand for new energy sources.

These will become essential as the finite supplies of fossil fuels become depleted, or considerations such as global warming necessitate a reduction in the rate at which they are consumed. Thus at some future time, the re-expansion of nuclear power is likely to be necessary. This would have a five-fold effect on the management of high level waste. These factors are as follows:

• Future generations within the next few hundred years would have a much larger amount of high level waste to manage than that accumulated in this generation and thus would have a powerful incentive to find the optimum solution.

• The continued use of nuclear power would ensure that rigorous regulation of the whole of the nuclear industry would be maintained.

• The stock of plutonium from the operation of existing power stations would provide a valuable energy source for future generations (for example, if used as the initial charges for a programme of fast breeder reactors, it could provide a fully sustainable source of energy) and thus could, at least in part, satisfy the requirement for equity between generations.

• The strong likelihood that the plutonium would be required in the relatively near future would render continuous reprocessing of irradiated fuel, using the existing capacity, the most economic way of providing this resource for future generations. At the same time, it would simplify the management of high level waste, as the half-lives of nearly all the other isotopes present in the waste would be much less than that of plutonium.

• Storage of the accumulated plutonium in a single, high security facility should, in UK conditions, avoid the possibility of any of the material being acquired by terrorists; the non-plutonium bearing high level waste would be an unattractive target for terrorists.

All of these factors should assist in securing public acceptance of the MRSS concept in this generation.

It is visualised that, in the UK, the various activities leading to the production of plutonium and high level waste, together with their use, storage and disposal would occur in the three phases shown in Table 1.

As much of the opposition to nearly every proposal for the management of high level waste purports to be based on ethical considerations, the principal need is to examine the validity of the current arguments.

The ethical aspects

Since the time of Aristotle and Plato, there have been many different schools of ethics, often with a conflict of views between contemporary schools. The present generation is no exception. There are two main schools: the deontological school, which considers the rights of the individual, both in the present and future generations, to be paramount and the utilitarian, which is more concerned with the greater good of the greatest number, both in this and subsequent generations.

Looking back over three decades, it appears that the opponents of nuclear power, notably in the USA, realised that the ideas of the deontological school could be used to provide an ethical basis for their opposition. Moreover, because of its concern for future generations and the extremely long term problems presented by high level waste, the views of the deontological school provided an ideal means for demanding extremely rigourous requirements and then demonstrating that it was unlikely that they could be met, leading to the conclusion that the use of nuclear power should cease as soon as possible.

The ideas of the deontological school also appear to have influenced those responsible for drafting the IAEA’s “Principles of Radioactive Waste Management”, which have been central to developing the regulations

A major weakness in the position of the deontological school, which undermines the moral high ground claimed by the opponents of nuclear power, is its failure to consider the right of the underpriveleged members of this generation compared with (by inference) the average members of future generations.

A further weakness of the arguments of the opponents of nuclear power in this respect is the very clear precept of the deontological school that, if this generation depletes a scarce resource (such as fossil fuel), it should provide a replacement for future generations. Thus, in the absence of proof that non-nuclear renewable energy sources would be able to replace fossil fuels in a way that will be acceptable economically and environmentally, there should be no objection on ethical grounds to the continuation of the use of nuclear power, reprocessing the fuel (both proven technologies) and stockpiling the plutonium as a future energy source. It should be noted that, on ethical grounds, the replacement energy sources should have as low a cost as possible consistent with other constraints, until such time as there is no scarcity of resources for improving the lot of the least priveleged members of society.

In spite of these deficiencies in the ethical arguments, it seems that the purveyors of deontological ethics have been successful in persuading the general public in most countries that high level waste presents a more serious hazard than the nuclear power stations which produce it; as a corollary, in several countries, the further use of nuclear power is now uncertain. This is possibly due to the emphasis on the longevity of the high level waste, although paradoxically, opinion polls show that in general, members of the public take little interest in possible events much more than 100 years ahead.

An alternative ethical model

The deontological school of ethics, although very concerned about the welfare of future generations, has little to say about how scarce resources should be used to benefit the poorer sections of the present generation, possibly to the detriment of future ones. The scarcity of resources for such purposes is shown by the inability of most of the developed countries to contibute the promised 0.7% of the GNPs to UN aid programmes; the average is less than 0.3%. The utilitarian school, however, would in principle seek to use scarce resources to provide an optimum distribution of benefits between the present and future generations, taking into account the current disparities in factors such as the provision of health care and opportunities for education within the present generation, on a world-wide basis.

Justice requires that future generations should not be made worse off than our own, but it does not require that they should be made better off than our own, bearing in mind that justice also requires some redistribution of resources in this generation. The moral obligation of the developed countries to reduce the risk of malnutrition and hunger in the developing countries is equally vital.

In relation to high level waste, the utilitarian ethics school would seek to reverse the tendency to overregulation, regarding this as self-defeating. In addition, it would take into account the disparity in the cost of a DUGD facility compared with an MRSS facility of equivalent capacity with a design life of, say, 2000 years (a factor of at least one order of magnitude) and the fact that the DUGD concept is not necessarily the optimum solution. Thus deferring an attempt to establish a DUGD facility would lead to a substantial saving of scarce resources. Utilitarian ethics would require that this saving should be divided partly between schemes to improve the present conditions of the most deprived members of society, preferably on a global basis, and partly on the development of methods for ultimate disposal of high level waste, for the benefit of future generations. The latter could include transmutation, and cancer research, as well as the development of a more realistic basis for the design of a DUGD facility, aimed at making the risk from a DUGD commensurate with those from other sources (including non-radioactive, non-biodegradable, toxic waste disposal facilities). Meanwhile, MRSS could provide a satisfactory solution in the following sets of conditions:

• World order is maintained and technological progress continues to accelerate at the present rate.

• World order breaks down and the technological basis of civilisation is lost. These conditions are assumed to last for about 500 years.

• World order is maintained but the rate of technological progress is reduced.

In the first and third scenarios, the future population will be at least as competant as we are in managing the high level waste. In the second scenario, there will be several factors tending to reduce the relative importance of the hazards of high level waste.

In the first scenario, there is a great difference, in terms of lives saved, between the benefit obtainable by spending a given sum on improving healthcare in the developing countries now or on seeking near-zero risk from high level waste disposal, even in scenario 2 conditions. For example, £100 million spent in this generation on seeking to maintain the radioactive hazard from drinking water in scenario 2 conditions, at the levels currently contemplated, might save about 20 lives over 1000 years. The same sum spent on helping the poorer developing countries to provide clean drinking water could save the lives of at least 500,000 children in the under 5 age group in this generation alone.

Other aspects of intergeneration equity

It is quite likely that within three generations, the UK will need its accumulated stock of plutonium as a low-cost, sustainable source of energy. Thus later generations, in the not-too-distant future, could receive a substantial direct benefit; a further benefit could result from the experience gained by this generation in the design, construction and operation of nuclear power stations, if this experience could be recorded in a suitable form. As these generations would benefit from the plutonium separated from the high level waste held in MRSS, this should more than offset the detriment from the latter.

Intermediate generations would incur costs in monitoring the MRSS and ensuring the security of the plutonium stocks. These costs would be offset to some extent by the reduction in CO2 emissions due to this generation’s nuclear power programmme, enabling them to use more fossil fuels within a given emissions quota.

A new ethical approach

There should be an acceptable compromise between the deontological and the utilitarian schools of thought.

There is a need to reconsider the ethical basis for high level waste management. In an era where there are great differences between living standards in the developed and developing countries, but resources to reduce the differences are scarce, it should be generally acceptable, on ethical grounds, to allocate a higher proportion of those resources to the certain needs of the under-priveleged in the present generation and less to the possible needs of future generations. This view has previously been put forward, notably to the NEA Radioactive Waste Management Committee, but the Committee excluded the intergenerational and intragenerational equity aspects, as it believed that these were too dependent on national political factors. Nonetheless, there was some debate in discussion sessions. The Committee stated: “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,” but did not pursue the matter further.

The International Commission on Radiological Protection (ICRP) has said that its fundamental principle is that radiation exposures of individuals and of the public as a whole should be kept as “low as reasonably achievable, economic and social factors being taken into account”, particularly where it is not certain that the exposures will occur. The ICRP also provides recommendations concerning the optimisation on radiological protection; these recoommendations are based on the utilitarian system of ethics rather than the deontological one. The ICRP emphasises that its recommendations are confined to protection against ionising radiation, and that its risks need to be treated with care rather than fear; its risks should be kept in perspective with other risks. The ICRP comments that all those concerned with radiological protection have to make value judgements about the relative importance of different kinds of risk and about the balancing of risks and benefits.

Public acceptance

There are a number of factors that are likely to affect the public acceptance of the MRSS concept, including fear of inadvertent interference or deliberate interference by terrorists and separation of the plutonium, to be stored under high security arrangements, from the high level waste itself, should allay the fearr of deliberate interference with the high level waste; inadvertent interference could be prevented by design.

With the passage of time, the storage building may deteriorate and monitoring for leakage may be neglected

Continuation of a nuclear power programmme, or at least the expectation that a re-expansion was likely, and an MRS programmme would ensure that a regulatory body, covering its costs by fees from its clients, would remain in existence, unless world order broke down. Attention should be drawn to the longevity of ancient Egyptian and Roman buildings (2000-4000 years) with little or no maintenance and to the provision that would be made in the design to detect and arrest any activity leached out by condensation.

Environmental changes and other external hazards could lead to the release of radioactivity

Major environmental changes, such as a large rise in sea level, could be foreseen in time to transfer the high level waste to another location. The designers of nuclear power stations have demonstrated to the UK regulatory authorities that the risks from other, less predictable external hazards (such as earthquakes) can be reduced to an acceptable level; for a MRSS, the technical problems would be simpler.

Concern that further work on alternative methods of disposal would be abandoned

Given the ‘breathing space’ provided by an MRSS with a design life of over 1000 years, there would be ample time to determine whether technological developments (transmutation; advances in medicine that would reduce the hazard to one of the chemical toxicity or reliable space transportation) would provide alternative solutions to DUGD.

Table 1: Phases in the use of nuclear energy and the management of high level waste