Geoscientific Research and Links to the Regulatory Framework for the Development of the Safety Case

Transcription

1 Julie Brown PhD, PGeo Son Nguyen PhD, Peng Integration Group for the Safety Case Paris, France October 6-8, 2015 e-doc: nuclearsafety.gc.ca

2 Content (CNSC) Context Early regulatory involvement The CNSC s Coordinated Assessment and Research Program Examples of (current and future) research projects Informing CNSC s regulatory framework 2

3 CNSC Overview Regulates the use of nuclear energy and materials to protect the health, safety and security of Canadians and the environment and to implement Canada s international commitments on the peaceful use of nuclear energy; and to disseminate objective scientific, technical and regulatory information to the public - 3

4 Context CNSC s regulatory framework provides expectations for the development of the safety case for geological disposal in Canada CNSC is conducting a Coordinated Research and Assessment Program (CARP) that supports the regulatory framework 4

5 Reasons for Early Regulatory Involvement Formal application comes after long periods of research and development in scientific, technical and social aspects Regulatory responses are required in a relatively short period of time for a formal application International guidance recommends regulators be actively involved early in the process before a formal application Atomic Energy Control Board (since the late 1980s) and CNSC (since 2008) have conducted and continue to conduct CARP 5

6 CNSC Involvement Pre-licensing Phase - CNSC Outreach Activities CLC visit CNSC (HQ) CNSC visit CLC CNSC Open House SASKATCHEWAN Communities in Step 3 Preliminary Assessments 3 MANITOBA 5. Ignace 9. Manitouwadge 10. Hornepayne 11. White River 13. Blind River 14. Elliot Lake 20. Huron-Kinloss 21. South Bruce 22. Central Huron ONTARIO QUEBEC 8 Communities not identified for further study 1. English River First Nation 2. Pinehouse 3.Creighton 4. Ear Falls 6. Nipigon 7. Red Rock 8. Schreiber 12. Wawa 15. The North Shore 16. Spanish 17. Arran-Elderslie 18. Saugeen Shores 19. Brockton

7 CNSC s Coordinated Assessment and Research Program Independent regulatory research Review key technical documents related to deep geological repository projects International collaboration Ensure that CNSC s regulatory framework is fit for purpose, based on international best practice and regulatory research 7

8 Objectives of the CARP Provide well-informed recommendations to decisionmakers and stakeholders on the safety of geological disposal Disseminate objective scientific and regulatory information Clarify regulatory expectations to proponents through CNSC s regulatory framework and ongoing dialogue 8

9 CNSC Research on Long-term Performance of Barriers PERTURBATIONS Excavation Heat generation Transport by groundwater Transport by gas Geological events Climate change Barrier performance GOAL Protection of people and the environment at all times CNSC RESEARCH Experimental/theoretical studies on thermo-hydro-mechanicalchemical processes in barriers Natural analogues Paleohydrogeology Safety assessment 9

10 Current Projects Thermo-hydro-mechanical modelling DGR scoping model HE-E experiment Rock model Seal model DGR updated model DECOVALEX SEALEX modelling SEALEX experiment IRSN collaboration UoT lab work Queen s lab work Independent Advisory Group Dating of fracture infill Natural analogues modelling Natural analogues Safety Assessment 10

11 A report to the (CNSC) By Mostafa Fayek, Univ. Manitoba and Julie Brown, CNSC 11

12 Definitions 10 4 Distance (metres) Anthropogenic analogues 0 Laboratory Experiments Time (years) 12

13 Analogues for Engineered Barriers (1) Source term: (UO 2 + fission products and actinides) - uraninite (UO 2.x + Pb) from uranium deposits U deposits similar to Yucca Mountain 44 Ma rhyolitic tuff, unsaturated zone, semiarid climate Nopal I Uranium Deposit, Peña Blanca, Mexico Yucca Mountain Peña Blanca Study Area Chihuah ua San Antonio Mexico City 13

14 Analogues for Engineered Barriers (2) Source term: test experimental dissolution rates over geological time-scales, radiolysis, criticality, radionuclide transport Uranous Oxide Uranyl Oxide Hydrates Nopal I Natural Analogue Uraninite (8-(8-3 3 Ma) Ma) Uraninite Uraninite (synthetic (synthetic UO 2 ) U 2 O) Ianthinite Schoepite /DehydrateSchoepite /Dehydrated d Becquerelite Argonne Drip Experiments Dehydrated Schoepite Schoepite Becquerelite Becquerelite Becquerelite (U 6+, U 5+, U 4+ ) Ca(UO 2 ) 6 O 4 (OH) 6 8(H 2 O) Uranyl Silicates Soddyite Boltwoodite Uranophane (3.8 ( Ma) Soddyite Uranophane, Boltwoodite Na - Boltwoodite Uraninite (U 4+ ) UO 2 Weathering Products Uraniferous Fe Oxyhydroxides (>300 (>300 ka) ka) Opal Opal and and Calcite Calcite (54 ka) (54 ka) Geologic Time Fayek et al (2006) Time (weeks) Murphy (2000) 14

15 Kiggavik Deposit, Nunavut, Canada 1 Image of core samples from the End Uranium Deposit, Kiggavik, Nunavut, Canada. Area 1 shows uranium minerals along a fracture, and areas 2 and 3 show secondary uranium mineralization within a clay-rich matrix. 15

16 Scientific Recommendations Anthropogenic analogues are deemed important for building public confidence in DGR concepts - therefore, researchers should attempt to be part of excavations to document artifact preservation and the soil encapsulating the artifacts Other recommended research: - analogue studies in near-field and far-field chemical environments - natural analogues for secondary traps for radionuclides, including microbial activity - natural analogues for site-specific matrix diffusion quantification - natural analogues for transport, including colloids and microbial activity 16

17 Implications of Analogues for Safety Case Development Analogues could constitute powerful arguments in support of the safety case at all stages National analogues may build more public support for a deep geologic repository because of geographical and cultural familiarity Analogues which are site-specific are even more powerful; for example: natural tracers and past glaciation Integrate natural analogue information with other studies (e.g., hydrogeology, rock mechanics) including laboratory experiments in order to take into account all temporal and spatial scales 17

18 Fracture Research in Southern Ontario Investigating fracturing and fracture-filling minerals: - stability of the geosphere in southern Ontario - contribution to regional geology - absolute age dating of fracture-filling minerals - support seismic hazard assessment Two year project initiated in September 2015 in collaboration with the University of Ottawa - preliminary field work, identification of potential field areas 18

19 Field Area Southern Ontario Map from Barnes et al. GSA poster 19

20 Fracture Research Example Barnes et al Current focus northern extension of the Clarendon-Linden fault, which is seismically active in northern New York state 20

21 Heater Experiments at Mont Terri Interaction of the Engineered and Geological Barriers HE-E experiment HE-E: Thermal(H)-Hydraulic (H)- Mechanical (M) experiment in bentonite and Opalinus clay 21

22 HE-E :Thermal-Hydraulic Evolution of Buffers Relative Humidity Temperature 22

23 HE-E: Some Lessons Learned RH (%) N2-3Heater N2-3C N2-3M N2-3H Postclosure duration (yrs) Re-saturation can take a very long time depending on T-H-M processes in buffer and host rock and their interaction What are the safety implications of very long re-saturation times? 23

24 Informing the Regulatory Framework (1) Updating the regulatory framework: analyze the issue consult with stakeholders - discussion paper - draft document finalize and publish 24

25 Informing the Regulatory Framework (2) Existing Regulatory Document: - Assessing the Long-Term Safety of Radioactive Waste Management (G-320) Need for guidance on siting - previous guidance was published in 1987: Geological Considerations in Siting a Repository for Underground Disposal of High-Level Radioactive Waste (R-72) 25

26 nuclearsafety.gc.ca facebook.com/canadiannuclearsafetycommission youtube.ca/cnscccsn twitter.com/cnsc_ccsn CNSC Copyright 2013