The International Atomic Energy Agency has served as a vehicle for the sharing of knowledge and experience on the peaceful uses of nuclear energy since it was established by the United Nations General Assembly in 1956.
Initially that sharing concentrated on the development of nuclear technologies and their implementation in nuclear power reactors and the production of nuclear fuel. It was soon realized that the processing, storage and disposal of radioactive waste would be an integral part of that development, and the IAEA held its first Scientific Conference on Disposal of Radioactive Wastes in Monaco in 1959. Decommissioning of nuclear facilities, including radioactive waste management, is an important component of a country’s nuclear energy policy.
The first IAEA publication in the field of decommissioning of nuclear facilities was issued in 1976 [1]. In the last 30 years, over 40 technical documents, conference proceedings, Technical Reports, Safety Series and Safety Standards Series publications have been issued covering specific aspects of decommissioning, such as technologies, safety and environmental protection, national policies and regulations, monitoring programmes, characterization of shut down facilities, and design and construction features to facilitate future facility decommissioning. The majority of early publications addressed decommissioning technologies, specifically decontamination and disassembly techniques and the management of resulting waste. These publica-tions were prepared in the early 1990s and mainly reflected decommissioning experience gained on a relatively limited number of smaller research reactors or prototype facilities [2, 3]. At that time, only feasibility studies or preliminary plans to decommission larger nuclear facilities were generally available.
Experience in the decommissioning of a wider range of nuclear facilities has become available over the last 15 years, and this has altered the decommis-sioning picture somewhat. In many countries, the dismantling of major prototype and power reactors and of research and development facilities has been viewed by the operators and governmental decision makers as an opportunity to demonstrate to the public that decommissioning can be conducted in a safe and cost effective manner. These decommissioning efforts have also allowed the further testing and optimization of decontamination and disassembly techniques, the evolution of new technologies, the improvement of management aspects, and the creation of a ‘decommissioning service market’
including specialized contractors and suppliers. These developments have been reflected in a number of recently updated IAEA publications, e.g. Refs [4–6].
It is currently recognized that, to a large extent, the liabilities associated with decommissioning should be identified at the design stage and regularly re-examined during the operational period. This topic has been the subject of an IAEA report that reviewed best practices worldwide in the area [7]. Many older facilities, however, were commissioned before the benefits of this guidance were realized. In the coming decade the rate at which large commercial power units are retired is expected to rise steadily as about 150 reactors commissioned in the 1970s begin to reach the end of their operational lives and are permanently shut down. Additionally, the closure of redundant support facilities, such as research laboratories, pilot plants, and fuel manufacturing and reprocessing plants, is expected to continue. It is inevitable that the rate of facility closures will increase in the future and add to the inventory of shut down facilities requiring eventual dismantling. The IAEA has recently published a study summarizing the status of the decommissioning of nuclear facilities around the world [8]. Figure 1 is from that study and shows the anticipated costs of the decommissioning liability by five-year periods.
As these facilities lose their capacity to generate power or support other nuclear energy activities, they are often seen only in terms of their decommis-sioning liability. This is the liability associated with the owner’s responsibility to
Years
Millions of US dollars 2001–2005 2006–2010 2011–2015 2016–2020 2021–2025 2026–2030 2031–2035 2036–2040 2041–2045 2046–2050
FIG. 1. Decommissioning liability by five-year periods [8].
keep the facilities in a safe condition and to eventually safely demolish them and dispose of the waste. In practice many such facilities and associated sites have significant potential for redevelopment.
Examination of the role of nuclear facility decommissioning in the move towards sustainable development suggests that this potential for redevel-opment should not be ignored. Sustainable develredevel-opment implies the need to combine economic development with conservation of natural resources such as land. In the case of decommissioning, the recycling of land implied by redevel-opment of a site offers a valuable means of avoiding the need to obtain further greenfield sites1. Sustainable development also implies economic development with maintenance of social and community integrity. Both of these benefits can be attained by the sensitive and organized redevelopment of sites to provide continuity of employment and new production opportunities. Finally, the principles of sustainable development suggest a more transparent and partici-pative decision making process than has been the practice to date in many aspects of nuclear development. This presents a challenge to the nuclear industry to learn new ways to consult with and engage a wider range of interested parties and be able to accept their inputs as legitimate. Experience to date with redevelopment both inside and outside the nuclear field suggests that successful engagement with interested parties can be a key factor in promoting outcomes that are both profitable for the operator and recognized as responsible and worth while by the wider community.
Some aspects of the potential for reuse and recycling of materials, equipment, buildings and sites when they reach the end of their useful life have already been considered in earlier Technical Reports [9, 10] and other IAEA publications [11, 12], notably the control of risks arising from potential residual radioactive contamination. This report will extend that work to consider a wider range of redevelopment and reuse issues. It will address specifically the way in which opportunities for redevelopment can influence decommissioning planning and promote rapid, effective and economic decommissioning. Actions that can be taken throughout the life of the facilities concerned to increase their redevelopment potential will also be discussed. Specific instances of reuse of sites as an integral part of the decommissioning process will be also presented.
1 For the purposes of this report, a greenfield site is a site that has been granted unrestricted release from regulatory control and where buildings have been demolished and no further productive use is planned.