H. H. Over on behalf of H. Weisshaeupl JRC Information Day in Romania on 11th May 2006

1. Nuclear Safety Research at the JRC/IE H. H. Over on behalf of H. WeisshaeuplJRC Information Day in Romania on 11th May 2006

2. High Flux Reactor • Multi-purpose research reactor • tank-in-pool, light water cooled/moderated, 45 MW • irradiation at: reactor core, reflector region, poolside • horizontal beam tubes, gamma irradiation facilities, hot cells labs (NRG) • The Programmes • At the service of medicine • Radio-Isotopes production • Boron Neutron Capture Therapy (BNCT) • At the service of reactor technology • Nuclear Safety (study of ageing materials) • Waste (study of transmutation and thorium cycle) • New reactors for the future (HTR, Fusion reactors, etc.) • At the service of research and industry • Neutron diffraction applications in materials science • Neutron radiography, gamma irradiation, activation analysis, etc

3. Nuclear Safety at IE ACCIDENT PREVENTION: Integrity of the Reactor Coolant System ACCIDENT MITIGATION: Integrity of the Confinement System • with investigation on: • material’s degradation • (irradiation, corrosion, thermal fatigue) • in-service inspection • structural integrity • preventive maintenance • with investigation on: • accident analysis • (test interpretation, code validation) - ‘severe accidents’ • accident management • system interaction • Horizontal activities: • probabilistic & risk assessment methodologies • data management & dissemination • training

4. 10 years of networking at Petten • Scope: • Mark 10 years of achievements in the European Networks (1993-2003) • Learn from the best scientific and technical achievements • Look at new R&D challenges in FP6 and beyond • Round table (industry, universities, R&D providers,DG-RTD, DG-TREN) • Establish possibilities and structure for future network actions

5. European Networks • EUROPEAN NETWORKS for a common understanding and harmonisation on key issues in nuclear reactor safety • strong Integration element • with hands-on research in key competence areas and reference laboratories • Key words: • Sharing/exchange of knowledge • Training & Education • Benchmark-Exercises and Workshops • Support to Harmonisation • General Deliverables: • Contribution to Best practices / Guidelines • Contribution to Code & Standards • Contribution to harmonized conclusions on safety assessment methodologies and procedures • (Web-based) Platform for virtual dissemination and learning • specific reports on emerging issues on demand

6. Ageing Materials Evaluation and Studies • Study RPV materials and other (internals) on irradiation embrittlement and thermal ageing • non-destructive ageing monitoring techniques • annealing and re-irradiation studies • AMES has taken major initiatives, including: • Kick-Off of the European Plant Life Assessment Forum (EPLAF) at Minatom 1999 • key role in defining the new Tacis/Phare projects on irradiation embrittlement • 20 participating organisations

7. European Network on Inspection Qualification • Assessment and qualification of Non Destructive Testing systems • Inspection qualification schemes • harmonisation of codes and standards • risk-informed inspection • The ENIQ-led European Non-Destructive Evaluation Forum (ENDEF) has elaborated a strategy on measures to improve in-service inspection in VVER and RBMK reactors • 64 participating organisations

8. Network for Evaluating Steel Components • NESC I Spinning Cylinder • NESC II MPA Pressurized Thermal Shock • NESC III Dissimilar Weld • NESC IV Multi-axial loading (ORNL Beam) • Thermal Loading • 25 organisations Benchmarks VVER Issues HTR Issues Training Dissemination Harmonisation NESC I Validation of entire structural integrity process through large-scale testing NESC IV

9. Network on Neutron Techniques Standardization for Structural Integrity • 39 organisations • To employ neutron based testing methods for gaining improved understanding on residual stresses and material degradation • To harmonise the corresponding experimental methodologies • Technical tasks: • pilot study on residual stress analysis with neutron diffraction, X-ray diffraction, computational analysis • study on stress relief heat treatment for novel repair welding methods • study on thermal ageing effects based on Small Angle Neutron Scattering

10. IASCC issues in LWR PWR + BWR: Baffle/former bolts support pins rod cluster control assemblies tip Core shroud top guide and core plate AMALIA test facility (Ageing of Materials under Load and and Irradiation-Assisted stress-corrosion cracking) Studies on stress corrosion cracking in NPP: autoclave with pneumatic loading device and a water chemistry preparation loop for fracture toughness testing, equipped with a device for bending tests of mini and standard Charpy-size specimens

11. Experimental Facilities (outside HFR) Implantation of simulated defects in components Fracture testing of steels Ultrasound measurements for detection of defects Impact testing and degradation monitoring lab Thermal fatigue rig for pipe test pieces Microstructural analysis

12. The way into FP 6projects related to structural integrity JRC-IE has adopted a new integrated approach to its R&D for safety of ageing nuclear plant, bringing together the established European networks with new groups in SAFELIFE

13. Analysis and Management of Nuclear Accidents • SEVERE ACCIDENTSto integrate the knowledge on severe accident phenomenology into common databases and reference analytical computer tools and to support conclusions for accident management measures • SA research results in a better understanding and evaluation of this very unlikely event - risks connected reduced • DESIGN BASIS ACCIDENTS (DBA)(limited effort)to support the transfer of knowledge, data and tools in some key issues of VVER-DBA safety based on JRC previous programs and expertise LOBI test facility

14. Networks on Severe Accident Research • PHEBUS-FP (integral in-pile tests) • European dissemination networks on:= Core degradation and fission product release= Circuit and containment aerosol behaviour= Containment chemistry • Over 30 participating organisations (incl. USA, Canada, Japan, S-Korea) • test interpretation, code validation and bench-marking, dissemination of the results:for improving accident mitigation Cadarache / F

15. The PHEBUS FP Test Matrix Contributions from JRC: Defining the test matrix / pre-test calculations for test planning / review and quality assurance of the Test Reports / contribution&coordination of the Dissemination Reports / Deputy Program Manager / promoting European participation (Dissemination Work-Shops) / etc.

16. Potential hydrogen explosion within a NPP containment as consequence of a SA • REACFLOW: 3D reactive gas flow code for turbulent combustion, deflagration and detonation of highly reactive gas mixtures in large, complex enclosures • Full scale simulation of the containment of a PWR: Without two external walls Non-nuclear application

17. Hydrogen Explosion in a Tunnel Following a release of H2 from a bus tank at 350 bar- pressure distribution on a temperature iso surface of 350 K

18. Probabilistic and Risk Assessment Methodologies & Reliability and Availability aspects

19. Methodological Developments • Reliability of passive safety systems • to develop new methods how to quantitatively assess reliability on passive safety systems in the lack of statistical failure data • PSA for Aging reactors • to cross-compare existing approaches in Europe and USA for including aging from active and passive components in PSA • PSA Quality Guide • to develop an international Guidance on how to verify quality level of a PSA study (together with IAEA) • PSA and RI-ISI (together with ENIQ) • to develop a Guidance on how to make best use of available PSA results for RI-ISI application • Quantification of uncertainty and sensitivity analysis • Comparative Energy Risk Assessment • to enable consistent and fair cross-comparisons of different energy systems in terms of risk and sustainability • Previous • Benchmark exercise on Expert Judgement Techniques in PSA Level2 • Benchmark exercise on Safety Evaluation of Computer Based Systems

20. Knowledge Dissemination • Mapping nuclear safety related practices and methods as used in the Enlarged EU • to provide all interested parties with status of top level safety documents and risk informed approaches http://www.energyrisks.jrc.nl

21. Safety of new Reactor Designs • Safety analyses and comparisons of a range of new reactor designs • Material and fuel issues related to HTRs • participation in: • Generation IV (GIF) • INPRO (IAEA) • OECD/NEA • MICANET“strategy for R&Dkeeping the optionfor nuclear fissionenergy open” • Co-ordination of theHigh Temperature Reactor Technology Network (HTR-TN)with technical support via irradiations of fuel, graphite and structural materials Schematic of the capsule used for irradiation exposures on HTR fuel pebbles in the Petten HFR

22. New Reactor Designs(VHTR, GFR, LFR, SCWR, SFR) Main activities: • Irradiations (HFR) • HFR-EU1, HFR-EU1bis, HFR-EU2, PBMRwith: fabrication, commissioning, analysis, … • Out-of-pile tests (GIF related) • (De-)Carburization tests for HTR components • High T material tests • Tests at supercritical water conditions • Corrosion tests (H2 production processes) • Analytical work • Neutronic/Thermal-hydraulic safety studies & design • Proposals for System safety improvements • HTR fuel database

23. Casks for high level nuclear waste design principles for high level waste packages: acceptance criteria associated for their structural integrity and functioning against loads that may occur under transport, storage, handling and the long-term deposition

24. SAFECASK: CASKS FOR HIGH-LEVEL RADIOACTIVE WASTE Waste packages constitute an important part in management of radioactive waste to ensure that there is no release of hazardous radioactive nuclides. The objective of SAFE-CASK is to develop design and assessment methods for nuclear waste packages and to provide scientific support to policy DG’s in this area. Decay of waste radiotoxicity with time, reduced need for monitoring Geological Disposal Casks • Very long functioning (100 000 years) • Cask constitute first barrier in multi-barrier system • Design account for very long processes (including climate change) Transport Casks • Short times • Cask primary barrier • Design against accident scenarios (dynamic loads, fire etc) Intermediate and Long-term Storage Casks in near- or sub-surface facilities • Intermediate times (50-500 years) • Cask primary or secondary barrier • Design against accident scenarios • Waste retrievable

25. On-line Data Information Network – ODIN (https://odin.jrc.nl) ODIN architecture Investments for hard- & software ~ 1 MEuro