Decontamination Techniques Used in Decommissioning Activities

admin — Wed, 16 May 2007 15:52:45 GMT

Decontamination is a major decommissioning activity that may be used to accomplish several goals, such as reducing occupational exposures, limiting potential releases and uptakes of radioactive materials, permitting the reuse of components, and facilitating waste management. The decision to decontaminate should be weighed against the total dose and cost. This document presents both proven and emerging techniques which may be used to accomplish the goals stated above. The planner must familiarise himself or herself with these techniques to integrate decontamination with other decommissioning activities.

At its thirteenth meeting on October 20-23, 1992, in Rome, the Technical Advisory Group of the NEA Co-operative Programme for the Exchange of Scientific and Technical Information Concerning Nuclear Installations Decommissioning Projects established a Task Group on Decontamination in order to prepare a state-of-the-art report on decontamination in connection with decommissioning. The work focused on decontamination for dose reduction as well as for waste decategorisation or for conditional or unconditional release of materials. The decontamination of both metallic and concrete surfaces was considered.

During its early meetings, the group developed a questionnaire, which was sent to decommissioning project managers. The information requested in this questionnaire covered the technical and economical aspects of the selected decontamination techniques. Project managers were asked to complete a separate questionnaire for each specific application of a given process, including actual data on the efficiency of the process as well as data on operating and investment costs.

This overview of decontamination techniques is intended to describe some of the critical elements involved in choosing techniques to address practical decontamination problems.

This overview of decontamination techniques is based on the results of the previouslymentioned questionnaire, which was received, reviewed and summarised for this report by the Task Group. The information presented here is not exhaustive, but does represent the state-of-the-art, for the techniques mentioned, as of June 1998. This overview is intended to describe some of the critical elements involved in choosing techniques to address practical decontamination problems.

The Decommissioning and Dismantling of Nuclear Facilities

admin — Wed, 16 May 2007 15:45:06 GMT

As nuclear facilities around the world continue to age, many countries will be increasingly faced with the task of taking them out of service (decommissioning) and dismantling them. In particular, they will also have to address the related issues of the release and/or reuse of materials, buildings and sites, and of radioactive waste management. Appropriate provisions will have to be made in terms of policy, financing and management. Depending on the path chosen, decommissioning and dismantling (D&D) of nuclear facilities may take a few years or several decades, especially for the larger ones. This range of possible timescales entails specific issues for decision making, and also has a wider impact by way of such issues as the sustainability of nuclear power and preservation of the well-being of local communities.

The NEA Radioactive Waste Management Committee (RWMC) has long recognised that D&D and waste management are intimately related and, since 1982, has been involved in various projects concerned with technical matters such as dismantling of plants and decontamination of materials. As these technologies have become mature, however, the broader aspects of managing D&D have come to the fore. These involve safety, societal and regulatory matters together with issues of costs and funding, all of which require informed dialogue between institutional and non-institutional parties. The RWMC has traditionally provided neutral ground for such wide debates, and has done so again in the field of D&D.

This report is intended to provide, in non-specialist terminology, a concise overview of the status of D&D of nuclear facilities and associated issues in NEA Member countries. The report draws upon a database of fact sheets produced to a standard format by individual Member countries that can be accessed online from the NEA website. In the context of this report, the term “nuclear facility” includes all facilities associated with the production of nuclear power, from mining of uranium, through fabrication of nuclear fuel, nuclear power plant operation, fuel reprocessing and waste management, including related R&D facilities, and research and demonstration reactors.

European

Decontamination Techniques Used in Decommissioning Activities

The Decommissioning and Dismantling of Nuclear Facilities