Joint Research Centre - European Commission

JOINT RESEARCH CENTRE
The European Commission's in-house science service
European Commission

Nuclear Fuel Cycle Simulations

Institute for the Protection and the Security of the Citizen

Action: 53201

Acronym: NUSIM

Summary:

JRC has developed methods (based on Monte Carlo techniques) to simulate the behaviour of NDA instruments used in nuclear safeguards. Physical models of most of the neutron devices have been also generated and validated. The simulation technique has become a valid and valuable tool to replace measurement every time the experiment is impossible (for instance due to lack of reference materials) or simply too cumbersome. The first application of modelling in the field of safeguards has been the calibration of NDA instruments, but recently an important new application avenue has been developed to describe nuclear installations and plants in connection to process monitoring techniques.

The back-end of fuel cycle is gaining more and more interest as far as final disposal of spent fuel approaches the operational phase. Measurement and evaluation techniques are required to confirm the inventory of nuclear material in spent fuel (mostly based on coupling measurements with burnup calculations), to detect partial defect in fuel assemblies (such as the Cherenkov Viewing Device) and to develop methods to re-establish the Continuity of Knowledge in dry storage containers in case of fault of C/S measures.

TAME laboratory developed a software tool that continuously monitors nuclear material flow through a reprocessing plant based on syntactic pattern recognition analysis. This JRC process monitoring tool aims at a verification of the consistency and coherency of plant operation with safeguards requirements, and so at near real time accountancy. This allows timely comparison of the operational reports of the facility and the inspector's observations.

Process monitoring and in particular solution monitoring is only possible if the plant is well equipped with active remote monitoring stations and with integrated regular re-calibration checks of passive components. Therefore the TAME laboratory continues research on mass/volume measurement with the aim to further increase practicality of tank calibration methods.

Concerning the new applications on nuclear security, PhyMod is focussing in the field of detection and activities will cover the improvement of metrology (through better discrimination of real and innocent alarms), testing and qualification of detection equipment and training.

Proliferation Resistance & Safeguards by Design. In the year 2009, the activity of the Proliferation Resistance and Physical Protection Expert Group PR&PP activity will evolve along two main lines, on one hand, the demonstration case study initiated on 2007 on the Example Sodium Fast Reactor, will be finalised and disseminated and lessons learned will be extracted by the group to improve the PR&PP methodology and the Implementation Guide. Secondly, according to indication of the GIF policy group, the PR&PP EG will establish closer collaboration with GEN IV designers in order to initiate their PR evaluations of GEN IV nuclear system. Specific activities are defined by the PR&PP group on a yearly basis and IPSC will contribute to the activity of the PR&PP Expert group and agreed deliverables that will be defined for 2009. Depending of resources available, it is further planned to strengthen participation in PR&PP of GIF, to continue to contribute to the INPRO project of IAEA mainly in the area of proliferation resistance and to extend the collaborations with US-Doe labs behind PR&PP commitments. In the area of safeguards by design, EC supported, in 2008, together with US-DoE the organisation of an IAEA workshop for launching a multi-annual task for designing guidelines to designers of nuclear systems to facilitate the application of international safeguards. The activity will be continued in 2009 and will benefit from input and interaction with other JRC actions.

Systems Analysis for Security Applications. Classic systems analysis/risk assessment techniques and related tools need special tailoring and development for a suitable application to a security environment. JRC ASTRA-3, Fault Tree analysis code has been especially developed for security related applications involving the need to model high probabilities values and non coherent tree which can be used to model mutually exclusive actions (e.g. different ways of attack). In 2008 ASTRA-3 was updated and internally extensively tested. The documentation will be finalised in 2009 and a distribution policy will be identified. Research activities will be carried out in targeted areas such as the simplification and treatment of large trees. The participation to the international activity aiming to promote the development of an exchange format for Probabilistic Safety Assessment (PSA) plant model (Open-PSA) will be ensured, this will also provide a workbench for further ASTRA-3 testing and developments. Other systems analysis techniques will be considered and explored for security application. The contribution to EC-US DoE bilateral SCORES project aiming to develop and apply a decision analyses model for rating the effectiveness of a nuclear operator accountancy systems will be ensured, depending on available staffing resources and profiles. The use of game theory for nuclear safeguards inspections will be explored.

Networking is an essential asset in a knowledge growing society. JRC was among the founders of the European Safeguards Research and Development Association (ESARDA) and of the European Safety Reliability and Data Association (ESReDA). Support and contribution to both associations will be ensured. The scope of activities of ESARDA is broadening. The ESARDA web site operated by JRC is becoming a repository of knowledge in the area of safeguards and past ESARDA proceedings and bulletins are fully accessible on line. During 2009 the ESARDA Symposium will be held in Vilnius (LT). The publication of the Bulletin will continue regularly and special issues will be planned, when needed, under the supervision of the editorial committee. The creation of the peer reviewed section in the Bulletin has contributed to raise the scientific and quality level of the contributions.