BACKGROUND OF EUROPEAN COMMISSION (EC) ACTIVITIES IN DECOMMISSIONING

Decommissioning is the final phase in the life cycle of a nuclear installa-tion and is to be considered part of a general strategy of environmental restora-tion after the final suspension of industrial activities. At present, over 110 nuclear facilities (nuclear power plants, fuel cycle facilities, particle accelerators and nuclear research installations) within the European Union (EU) are at various stages of the decommissioning process and it is forecast that at least a further 160 facilities will need to be decommissioned over the next 20 years (within the present 15 EU member States). Enlargement of the EU would contribute to a rapid increase in the number of nuclear facilities to be decom-missioned (at least 50 facilities).

Since 1979, the EC’s Directorate-General for Research has conducted four successive five-year research and development programmes on the decom-missioning of nuclear installations performed under cost sharing contracts with organizations within the EU. The main objective of these programmes was, and still is, to establish a scientific and technological basis for the safe, socially acceptable and economically affordable decommissioning of obsolete nuclear installations.

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* The views expressed here are those of the authors and may not necessarily reflect those of the European Commission.

These programmes were carried out by public organizations, research institutes and private companies in the member States under shared cost con-tracts and through concerted actions. The main objectives of these activities were to strengthen the scientific and technical knowledge in this field, with a particular view to enhancing safety and environmental protection aspects, and minimizing occupational exposures and dismantling costs as well as radioactive waste arisings.

Since 1979, more than _€60million have been spent on:

— Development of decontamination and dismantling techniques for differ-ent kinds of nuclear installations;

— Technologies for waste minimization, such as melting of steel compo-nents;

— Development of decommissioning strategies and management tools;

— Development of remote handling systems for high activity components (TELEMAN programme);

— Development of planning and management tools for decommissioning projects

In the beginning of the 1990s, four pilot decommissioning projects were chosen to compare the differences in the approach of a:

— fuel processing plant (AT1 in La Hague),

— gas cooled reactor (WAGR in Windscale),

— boiling water reactor (KRB-A Gundremmingen in Germany),

— pressurized water reactor (BR3 in Belgium).

Five years ago, a WWER type reactor (Greifswald in Germany) was added to this list of pilot decommissioning sites.

The WAGR dismantling, for instance, served as a bridgehead for the future dismantling of graphite gas cooled reactors. It was an extremely impor-tant textbook case, which rightly used the most modern techniques, thus enabling the choice of the scenario that is best suited to lower the doses received by the operators, the costs and the volumes of the wastes.

Operations to remove the reactor internals were undertaken with the use of innovative dismantling techniques involving amongst others:

— Computer controlled remote dismantling machine using stereoscopic television cameras to assist in the dismantling process;

— Acoustic cleaning of electrostatic pre-filters;

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— Ultraviolet laser to decontaminate vital parts of the machine before maintenance;

— Video gamma camera to identify and sort radioactive materials and hot spots.

The dismantling of the BR3 in Belgium concentrated successfully on developing dry and underwater cutting techniques for the high activity core internals. The Greifswald decommissioning project, one of the largest in the world, started the stage 3 dismantling of five commercial WWER-440 reactors in Greifswald and one WWER-70 reactor in Rheinsberg. The remote con-trolled dismantling of the first reactor pressure vessel and reactor internals, using a newly developed robotic system, will start in 2001.

In KRB-A (Germany), a 250 MW(e) boiling water reactor, the disman-tling of the core internals, the heat exchanger, the activated concrete bio-shield and the reactor pressure vessel was finished.

The AT1 reprocessing plant in France has successfully completed its decommissioning period and the site is currently being cleaned up for further use.

Within the EC programme, two databases on decommissioning have been created:

— EC DB TOOL for collecting technical performance data;

— EC DB COST for collecting data on waste arisings, doses, etc.

Both are now being merged into one database, EC DB NET, which is available on the Internet (so far only for members of the project group).

The interest shown by the IAEA, the OECD/NEA and the EC in the development of a common understanding of the decommissioning process led to the creation of a list of ‘Standardized Decommissioning Cost Item Definitions’ (INCOSIT), another project under FP-4, to ease worldwide com-parability and transferability of data on decommissioning. With this set of stan-dardized decommissioning cost items it should be possible to create a common tool for the calculation of whole decommissioning projects, regardless of the type of reactor or the chosen method of dismantling. Under FP-5, a benchmark exercise on the decommissioning costs of WWER reactors will be executed.

Similar activities, using the same list, are currently being conducted in the IAEA and OECD/NEA.

With the support of the EC, conferences, workshops and seminars were held on:

— Melting of dismantling steel,

— Decommissioning strategies,

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— The use of databases,

— Dismantling techniques.

Under the 4th Research Framework Programme of the EC (1994–1998), a 20 year period of EC funded research activities in the decommissioning field was concluded, which has been qualified as essential in that sector. It can be stated that most of the dismantling techniques and technologies involved in the decommissioning process have reached industrial stage. A large number of final reports and publications on various aspects of decommissioning are available at our EC service or from the relevant authors.

The activities in decommissioning which are supported in FP-5 are clearly shifting from research on technology to:

— dissemination of results from former research activities,

— exchange of experience and provision of training,

— collection of relevant data from decommissioning projects,

— development of decision-supporting and management tools,

— integration of the needs of the candidate countries.

The current work programme in nuclear fission research supports the creation of networksto:

“exchange information between national and Community sponsored research; promote exchange and feedback between the research and user communities; achieve consensus or a common understanding on key tech-nical/scientific issues; identify research needs and develop strategies for how they can be addressed, promote training activities within a specific area, etc.”¹

And in the ‘Communication of the Commission on the European Research Area (Oct.2000)’, which will be created within the period of FP-6 (2002–2006), the EC proposes ‘European Networks of Excellence’ around spe-cial areas of interest.

For this purpose the EC decided to support the creation of a ‘Thematic Network on Decommissioning’ (www.ec-tnd.net) as an effective instrument for facilitating these objectives. This network is in line with the EC’s current and future intentions of interconnecting individual, national and European initiatives in a certain field and has the ability to serve as a forum for

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1 Nuclear Energy Work Programme, 1998 to 2002, Official Journal L26 (1999).

extended exchange of experience and the integration of future members from Eastern Europe. It will involve research facilities, the decommissioning indus-try, ongoing and future decommissioning projects as well as authorities and regulators.

It is foreseen to provide free access to the EC DB NET database for the members of the network, with the objective on one side to disseminate col-lected experience from different decommissioning projects, but also to receive more data to improve the usability of the database. An extended set of data and a large number of clients are indispensable conditions for a long lived database.

Besides the Thematic Network and the database, some other projects which deal with innovative remote dismantling techniques or cost estimation for the decommissioning of WWER nuclear power plants receive substantial financial support from the EC. There is also support given to the organization of training courses and to the creation of a compendium on the state of the art in decommissioning, taking into account experience gained in this field during the last two decades.

Recently, other services of the EC, such as the Directorate-General for Energy and Transport, in continuation of the Directorate-General for Environment, have also contributed with studies and projects on decommis-sioning but with an emphasis on safety and regulations, environmental impact assessments and the economic implications as major topics. As an example, the recent “Study on the Methodologies for the Calculations and Financial Planning of Decommissioning Operations”, carried out by an international consortium, shed light on the impact of the main driving factors involved in the strategic decision making on decommissioning.

2. THE ENLARGED EU

The process of enlargement of the EU has also brought in new demands to the EC in the nuclear area. As part of the negotiations for accession, the Council, with the help of experts from the member States and the relevant services of the EC, started a safety review process of nuclear installations, including those whose closure was already planned upon the request of the EU.

These nuclear power plants receive specific treatment by the EC, which has allocated funds, directly or through international financial institutions, to support measures oriented to immediate pre-decommissioning activities, and also to compensate for the effects of early closure on the energy systems and the economies of the affected countries.

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