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LLW challenges and developments FINAL pptx
- 1. International Atomic EnergyAgency LLW disposal: trends, developments and challenges P. Ormai IAEA, Waste Technology Section International Workshop on the Safe Disposal of Low Level Radioactive Waste, 3-5 Febr. 2015, Montrouge, France
- 2. International Atomic EnergyAgency Topics • Introductory remarks • Trends in LLW disposal • Latest developments • LLW disposal challenges • IAEA’ involvement
- 3. International Atomic EnergyAgency Source of information • DISPONET network (meetings, web site) • WES projects (ISAM, ASAM, PRISM, PRISMA, HIDRA) • TC national, regional, inter- regional projects • Document preparation • Member States reporting (Joint Convention) • IAEA data bases IAEA activities WES: Waste and Environmental Safety Section DISPONET: International Network for the Disposal of Low-level Radioactive Waste ISAM: Improvement of Safety Assessment Methodologies for Near‐surface Disposal Facilities ASAM: Application of Safety Assessment Methodologies for Near Surface Waste Disposal Facilities PRISM: Practical Illustration and Use of the Safety Case Concept in the Management of Near-Surface Disposal PRISMA: Application of the Practical Illustration and Use of the Safety Case Concept in the Management of Near-Surface Disposal HIDRA: Human Intrusion in the context of Disposal of Radioactive Waste
- 4. International Atomic EnergyAgency 1. TRENDS Long road from the beginning to the current disposal practices What makes the differences? Not only the looks! Several disposal facilities were entered into operation before current regulatory standards took effect and IAEA requirements and guidance, SA methodologies and recommendations for QM systems became available. Tumble tipping
- 5. International Atomic EnergyAgency LLW disposal by now is a matured practice • Coherent safety regime • The safety principles and safety requirements to be applied in all RWM activities including disposal are established (SF-1, GSR Part 5, SSR-5) • There is a great deal of experience in LLW disposal • Good operation records • more than 100 LLW repositories are in operation all over the world • some of them have already been safely closed down • Commensurate with the diverse range of wastes, a diverse range of disposal solutions have been implemented and proposed for the broad range of LLW
- 6. International Atomic EnergyAgency • Many ways to design disposal facility: different geometries, different configurations, different materials • Different disposal systems have been developed, but no unique design – several types suitable for different conditions • Repository type/design depends on: • overall disposal strategy in the country (how many facilities?) • political decisions • legislative restrictions • waste inventories • nature of the site (host media) and its surroundings • social acceptance • climate
- 7. International Atomic EnergyAgency Trench type disposal facilities NTS - Area 5 (USA) Peña Blanca (USA) Richland (USA) Ezeiza (Argentina) Vaalputs (South Africa) L’Aube (France) El Cabril (Spain) 7 Australia
- 8. International Atomic EnergyAgency Engineered near-surface disposal concepts La Manche, France El Cabril, Spain Mochovce, Slovakia L’Aube (CSA), France Rokkasho, Japan Beilong, China NorthWest, USA Dukovany, Czech 8 Drigg, UK
- 9. International Atomic EnergyAgency Subsurface facilities, geologic repository SFR, Sweden Olkiluoto, Finland Bátaapáti, Hungary Morsleben, Germany 9 LOVIISA - Finland HIMDALEN - Norway
- 10. International Atomic EnergyAgency • There is no “best” design for a LLW disposal facility • The design should reflect the circumstances and the level of hazard or risk • Technical options based on compliance with national policies, available funding and public sensitivities. • Appropriate selection and optimization of technical options is important in terms of safety, economics and efficiency • Available technologies must be assessed. Lessons learnt on disposal option selection
- 11. International Atomic EnergyAgency Evolving recognitions (1) • Adaptive approach is preferred • Meeting safety requirements should be commensurate with the hazard associated with the waste and the longevity of the hazard (graded approach). • Disposal facilities adapted to particular waste streams (VLLW, LLW, ILW, DSRS, NORM). • Safety case, safety assessment • SA cannot, itself, adequately demonstrate the safety of the disposal system • A holistic view is needed, with a broader range of arguments and activities to justify disposal of RW (safety case) • Decision making at different stages in the facility lifecycle, using the Safety Case • Understand the processes (colloids, complexing agent, corrosion, gas generation, sorption of nuclides onto barrier materials)
- 12. International Atomic EnergyAgency Evolving recognitions (2) • Effective governance in disposal programmes is vital (transparent decision making, adaptive, flexible, collaborative approach) • Public participation in environmental impact assessment (EIA) ensures an open, balanced process and strengthens the quality and credibility of a project's review. • Important idea of translation of ‚siting’ to ‚hosting’ a repository whereby a local community is empowered • While the safety is the unchallengeable priority, the cost implication of the disposal has come to the forefront in most of the disposal development programmes • Cost (assessment): in relation to optimisation and improved efficiency • The notion of the best (‚optimal’) disposal solution is elusive Deciding what would be an optimal solution is complicated by many factors (e.g., policy constraints, and public acceptance, siting constraints, the specific waste streams, resources available) • Continual improvements in disposal are imperative
- 13. International Atomic EnergyAgency Continual improvements • A number of countries have already initiated or planning R&D studies: • for increasing knowledge and confidence in safe operation • enhance and strengthen the plausibility and robustness of disposal safety case (enhancing confidence in safety case) • deepen and strengthen stakeholder confidence • Priorities of a R&D programme • improve knowledge of waste characteristics • information on time development of the EB structures • EB degradation and structural stability • reduce identified uncertainties • confirm the assumed performance of the disposal system • optimise the system by increasing performance and robustness of performance of the disposal system in cases of failures • stay abreast of international developments and best practices on SAs and SCs
- 14. International Atomic EnergyAgency ‚Matured’ disposal facilities Facilities in design or construction phase Disposal facility need refurbishment and / or safety upgrading 2. LATEST DEVELOPMENTS
- 15. International Atomic EnergyAgency Expansion, disposal optimization (driver: cost) • France • enable a safe industrial disposal of large components • filling optimization of cell • rubble recycling • UK • volume reduction program • disposal of high-volume low activity waste (VLLW) at appropriately licensed commercial hazardous waste landfill sites • Sweden • extension of SFR • extra tunnel for the RPVs • Hungary • Optimizing the tunnel filling ‚Matured’ disposal facilities
- 16. International Atomic EnergyAgency Current projects and future plans Talmessi, Iran Vrbina, Krško (Slovenia) Dessel (Belgium) Wolsong, Korea Radiana, Bulgaria Switzerland Russian Fed., Brasil Jordan, Turkey, Pakistan, Bangladesh Phillipines, Malaysia, Ghana: plans for borehole disposal is in progress Kinkardine,Canada Konrad, Germany Saligny, Romania Lithuania
- 17. International Atomic EnergyAgency 3. CHALLENGES A. continuous or recurring challenges B. new challenges C. challenges remained from the past • safety • regulatory • engineering • economic • societal
- 18. International Atomic EnergyAgency A. Continuous or recurring challenges Issues for ‚mature’ disposal facilities: • maintain safe operation – maintain the public confidence • optimise management route - integrated view • re-licensing • handle new waste streams • expansion (add new disposal units) • prepare for closure – demonstration of safety concept • preserve memory • Issues for new disposal facilities • Siting (stakeholder interaction), licensing,… • ‚Evergreen’ topics for LLW disposal • Demonstration safety (SA, safety case) • human intrusion • managing uncertainties • managing ‚hotspots’, inhomogeneity (ASAM project) • Derivation and verification of WAC • Monitoring / surveillance programme
- 19. International Atomic EnergyAgency B. New challenges • New types of waste, new regulations or guides, new events • With the expanding nuclear industry and the increased age of nuclear plants, some categories of waste that were of minor importance in the past are now becoming significant and require adequate attention. Examples are: • LLW from decommissioning and dismantling of old nuclear installations • radioactive graphite from nuclear reactors, amount to over 3,000 tonnes per reactor (14C and 36Cl) • chemotoxic or biotoxic materials possibly present in various types of wastes • sodium and sodium/potassium alloys, which arise from the decommissioning of liquid metal fast reactors (LMFR)
- 20. International Atomic EnergyAgency END POINT Decay storage Surface trench Tailing dam Engineered surface facility Intermediate depth facility Geologic repository BOSS DSRS Short-lived Long-lived SHARS B1. Disposal of DSRS Disposal options for DSRS vary depending on the activity levels and types of radionuclides in the sources. Borehole disposal is not a new concept • In the former USSR: „RADON” facilities • USA: Greater confinement boreholes (e.g. Nevada test site) • South Africa – Pelindaba • Western Australia – Mt Walton “Intractable Waste Facility” • Russian Federation: large diameter borehole (LDB)
- 21. International Atomic EnergyAgency BDC concept: safety philosophy ‘Borehole facilities offer safe, simple, economic alternative for all DSRS Easier’ disposal derives from the small volume and nature of the waste No decrease in safety standards, these to be set by national authorities, backed up by international guidance, as usual South Africa Demo
- 22. International Atomic EnergyAgency International Atomic Energy Agency June 2010 / 22 WAC conformity checking: Radiological characterization of large size waste packages Source: Lucien Pillette-Cousin, AREVA TA Handling weight : 100 - 300 tons, diameter: 2- 4 m height : 15 - 20 m B2. Management of bulk waste Criteria for optimizing large component management include safety, technical, socio-economic, economical issues
- 23. International Atomic EnergyAgency • Transport to disposal site • abnormal load • special arrangement • special vehicle • road logistics
- 24. International Atomic EnergyAgency International Atomic Energy Agency June 2010 / 24 Disposal • New configuration of the disposal unit Long term safety aspects: • avoid ‚’hot spot’ • provide mechanical stability of the cell (grouted with a cementitious material) • high pH reduces corrosion rate
- 25. International Atomic EnergyAgency Operational shortages • no WAC • no QA/QC • lack of appropriate monitoring • insufficient inventory record keeping • lack of expertise • lack of resources • lack of safety culture • handling DSRS • waste characterisation facility degradation (erosion, inadequate cover, deeply rooting plants or burrowing animals, subsidence) waste package degradation (corrosion, effects of gas formation, biodegradation of certain waste types) No adequate infrastructure Facility evolution C. Challenges remained from the past Causes of safety concerns
- 26. International Atomic EnergyAgency Requirement 26: Existing disposal facilities The safety of existing disposal facilities shall be assessed periodically until termination of the licence. In the event that any requirements set down in this Safety Requirements publication are not met, measures shall be put in place to upgrade the safety of the facility, economic and social factors being taken into account.
- 27. International Atomic EnergyAgency JC Article 12. EXISTING FACILITIES AND PAST PRACTICES „Each Contracting Party shall in due course take the appropriate steps to review: …the results of past practices in order to determine whether any intervention is needed for reasons of radiation protection …” PAST PRACTICES CORRECTIVE ACTIONS • Modernisation, refurbishment, infrastructure development • Change of design (capping system, drainage system, etc.) • Additional EBs • Waste retrieval
- 28. International Atomic EnergyAgency International Atomic Energy Agency June 2010 / 28 Some countries still are at the very beginning of the upgrading process. Some countries have successfully solved their problems and are assessing the obtained results. Upgrading of waste disposal facilities Managing historic LLW sites and upgrading of waste disposal facilities is performed or planned in a number of countries.
- 29. International Atomic EnergyAgency Lessons learnt: To make all reasonable improvements in order to upgrade the safety of existing facilities may prove to be a much more complex task than had initially been expected. Some issues remain, mainly concerning: • Selection of a solution to achieve safety; • Long term safety considerations — the existing facilities should be upgraded so as not to create future problems. • Technical procedures for safe retrieval and sorting of waste; BUT it should be and can be done! 29
- 30. International Atomic EnergyAgency Guidance for waste management following an accident or incident Disposal of radioactive waste resulting from a nuclear accident Predisposal Management of Radioactive Waste in the Aftermath of Severe Nuclear Accident: Challenges, issues and lessons learned Report on environmental remediation after a nuclear or radiological accidents: approaches, tools, techniques, and equipment A series of reports are being drafte which primarily focus on technical, economic and socio-political aspects of waste management after emergency situation Advance planning for waste management in the aftermath of nuclear accidents New priority / challenge
- 31. International Atomic EnergyAgency IAEA’ Assistance IAEA adjusts its support to specific Member State needs: • Support newcomer countries on disposal • Support non nuclear countries with limited inventory of waste on disposal • Support enhancing knowledge on disposal (e-learning, training) • Peer review on disposal plans • Support on implementing a borehole disposal for very small inventories • Demonstration of BDC concept • Information exchange and research cooperation on any emerging trends and needs for Member States with advanced programmes • manage large volumes of waste as may arise after a nuclear accident • Share experience on post accident related waste disposal
- 32. International Atomic EnergyAgency Thank you for your attention