Nuclear Power and the Environment

RSC Publishing

It is often forgotten that the human species has evolved in an environment surrounded by natural sources of radioactivity. These sources are as diverse as cosmic ray particles from space, potassium-40 in igneous rocks and the radioactive decay products of radon, a gas emanating from the land beneath our feet. Indeed, for many people, the so-called ‘‘radon daughters’’ pose the largest health risk incurred by breathing air indoors. However, in the public mind, artificial radioactivity is far more important, and since the cessation of atmospheric nuclear weapon testing this is primarily the radiation associated with the nuclear fuel cycle. This has already caused major pollution issues and continues to have the potential to do so, unless handled with great compe­tence. The early years of nuclear power saw great enthusiasm for building nuclear power stations stimulated by lavish but unfulfilled promises of cheap electricity for all. This was followed by a period of disillusionment as the true costs of building nuclear power stations, generating the power and subsequent decommissioning became fully recognised, and the majority of investment went into fossil fuel sources of power. However, recent years have seen an increasing acceptance by politicians and the general public of the inevitability of damaging levels of climate change unless greenhouse gas emissions are curbed, and one of the few effective ways of doing so is through the adoption of nuclear power as a primary means of energy generation.

This volume is designed to provide an overview of some of the most important aspects of this field of science. In the first chapter, John Walls maps the technical and societal context in which nuclear power has existed since the first construction of experimental reactors. This serves to highlight many of the important issues which are taken up in later chapters, including issues such as the availability of uranium as a nuclear fuel, the consequences of fuel reprocessing, the economics of power generation and the costs of decommissioning. Other issues not explored elsewhere in depth within the volume, such as public attitudes to nuclear power, are also touched upon. The issue of nuclear fuel cycles and their by-products and consequences

Issues in Environmental Science and Technology, 32 Nuclear Power and the Environment Edited by R. E. Hester and R. M. Harrison © Royal Society of Chemistry 2011

Published by the Royal Society of Chemistry, www. rsc. org

for the environment are expanded upon in the second chapter by Francis Livens, Clint Sharrad and Laurence Harwood. In particular, this chapter highlights the limitations posed by the availability of uranium as a fuel, and the advantages and disadvantages of fuel reprocessing. The latter was developed originally largely to generate plutonium for military purposes but has gained a rather poor reputation because of discharges to the environment, and most countries now plan to store rather than reprocess spent fuel.

One of the major drivers of public opinion on nuclear power is the occurrence of nuclear accidents. Some, such as Windscale, Three Mile Island and Chernobyl, are well known to all but others occurring in the former Soviet Union were kept secret from the general public, yet have generated contamination which persists to this day. In the third chapter, Jim Smith describes the causes and implications of these accidents and puts the topic into context. Both major and minor accidents and planned releases of radioactive materials have led to land contamination and have generated low-level wastes which need to be stored safely. In the fourth chapter, Jon Lloyd, Francis Livens and Rick Kimber outline the issues raised by such contamination and describe some of the consequences and the available remediation techniques. Perhaps the greatest Achilles’ heal of nuclear power generation is the fact that decommissioning of nuclear sites is required at the end of their active life, although interim ‘‘storage’’ may be used to allow cooling of the radioactivity by decay of the shorter-lived radionuclides. In Chapter 5, Anthony Banford and Richard Jarvis describe the legacy of contaminated nuclear sites and the approaches taken towards decontami­nation, and their positive and negative attributes.

The sixth chapter, by Katherine Morris, Gareth Law and Nick Bryan, deals with the geological disposal of higher activity wastes. This is currently a topical issue for many countries who have declared policies of con­structing deep geological repositories for high and intermediate level waste with a view to safe storage on a timescale of at least a million years. The many considerations which go into the siting and design of such a reposi­tory are considered in this chapter. In the seventh chapter, by Joanna Renshaw, Stephanie Handley-Sidhu and Diana Brookshaw, the pathways of radioactive substances in the environment are described. This highlights how the chemistry of the actinides and fission products determines their behaviour in the environment which, in turn, influences their mobility and ultimate potential to cause exposure of humans and other biota. Chapter 8, by Brenda Howard and Nick Beresford, describes how radioactive sub­stances translocate into biological organisms and the resultant dosimetry, and in Chapter 9, Richard (Jan) Pentreath describes the human con­sequences of exposure to environmental radioactivity. For many years, radiological protection was based upon the concept that measures adequate to protect human health would also be protective of the non-human biota. This paradigm has now shifted to one in which assessments are made of the dose to representative animals and plants and the likely consequences of those doses.

Overall, the volume provides a selective but broad overview of current issues in this long-standing but increasingly topical field, which we believe will be of immediate and lasting value, not only to practitioners in gov­ernment, consultancy and industry but also to environmentalists, policy­makers and students taking courses in environmental science, engineering and management.

After the receipt of chapters from authors but before proof correction, the Japanese tsunami caused damage to the Fukushima nuclear plant which went into partial meltdown. At the time of production of this volume this situation was continuing with very little definitive information available. Where possible, authors have included this in their chapters but it is clear that a more complete view of the incident will only emerge well after the production of this book.

Ronald E. Hester Roy M. Harrison

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