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Probabilistic Performance Assessment vs. the Safety Case Approach

  • François Diaz-Maurin (a1) (a2) and Rodney C. Ewing (a1) (a3)

The “safety case” approach has been developed to address the issue of evaluating the performance of a geologic repository in the face of the large uncertainty that results for evaluations that extend over hundreds of thousands of years. This paper reviews the concept of the safety case as it has been defined by the international community. We contrast the safety case approach with that presently used in the U.S. repository program. Especially, we focus on the role of uncertainty quantification. There are inconsistencies between the initial proposal to dealing with uncertainties in a safety case and current U.S. practice. The paper seeks to better define the safety case concept so that it can be usefully applied to the regulatory framework of the U.S. repository program.

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1.Swift, P.N., in Geological Repository Systems for Safe Disposal of Spent Nuclear Fuels and Radioactive Waste (Second Edition) edited by Apted, M.J. and Ahn, J. (Woodhead Publishing, 2017), pp. 451473.
2.Ewing, R.C., Tierney, M.S., Konikow, L.F., and Rechard, R.P., Risk Anal 19, 933 (1999).
3.U.S. NRC, An Assessment of Accident Risks in U.S. Commercial Nuclear Power Plants (U.S. Nuclear Regulatory Commission, Washington DC, USA, 1975).
4.Bredehoeft, J.D., England, A., Stewart, D., Trask, N., and Winograd, I., Geologic Disposal of High-Level Radioactive Wastes: Earth-Science Perspectives (U.S. Department of the Interior, U.S. Geological Survey, Alexandria, VA, USA, 1978).
5.Campbell, J.E., Dillon, R.T., Tierney, M.S., Davis, H.T., McGrath, P.E., Pearson, F.J., Shaw, H.R., Helton, J.C., and Donath, F.A., Risk Methodology for Geologic Disposal of Radioactive Waste: Interim Report (Sandia National Laboratories, Albuquerque, NM, USA, 1978).
6.Cranwell, R.N., Guzowski, R.V., Campbell, J.E., and Ortiz, N.R., Risk Methodology for Geologic Disposal of Radioactive Waste: Scenario Selection Procedure (Sandia National Laboratories, Albuquerque, NM, USA, 1990).
7.OECD Nuclear Energy Agency, Disposal of High-Level Radioactive Wastes: Radiation Protection and Safety Criteria, Proceedings of an NEA Workshop, Paris, 5-7 November 1990 (Nuclear Energy Agency, Organisation for Economic Co-operation and Development, Paris, France, 1991).
8.OECD Nuclear Energy Agency, Disposal of Radioactive Waste: Review of Safety Assessment Methods, A Report of the Performance Assessment Advisory Group of the Radioactive Waste Management Committee (Nuclear Energy Agency, Organisation for Economic Co-operation and Development, Paris, France, 1991).
9.Rechard, R.P., Risk Anal 19, 763 (1999).
10.U.S. Environmental Protection Agency, Title 40 Code of Federal Regulations Part 191, Environmental Standards for the Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes; Final Rule (1985), pp. 3806638089.
11.OECD Nuclear Energy Agency, The Nature and Purpose of the Post-Closure Safety Cases for Geological Repositories (OECD NEA, Paris, 2013), p. 53.
12.IAEA, The Safety Case and Safety Assessment for the Disposal of Radioactive Waste (International Atomic Energy Agency, Vienna, Austria, 2012), p. 120.
13.OECD Nuclear Energy Agency, Post-Closure Safety Case For Geological Repositories: Nature and Purpose (Nuclear Energy Agency, Organisation for Economic Co-operation and Development, Paris, France, 2004), p. 54.
14.Hedin, A. and Andersson, J., SKB’s Safety Case for a Final Repository License Application (OECD Nuclear Energy Agency, Paris, France, 2014), p. 8.
15.Freeze, G., Voegele, M., Vaughn, P., Prouty, J., Nutt, W.M., Hardin, E., and Sevougian, S.D., Generic Deep Geologic Disposal Safety Case, Rev 1 (Sandia National Laboratories and Argonne National Laboratory for U.S. Department of Energy, Used Fuel Disposition Campaign, 2013), p. 356.
16.MacKinnon, R.J., Sevougian, S.D., Leigh, C.D., and Hansen, F.D., Towards a Defensible Safety Case for Deep Geologic Disposal of DOE HLW and DOE SNF in Bedded Salt (Sandia National Laboratories, Albuquerque, NM, USA and Livermore, CA, USA, 2012), p. 62.
17.Weiss, W., Ann ICRP 41, 294 (2012).
18.Metlay, D., in Prediction: Science, Decision Making, and the Future of Nature (Island Press, Covelo, CA, 2000), pp. 199228.
19.Rechard, R.P. and Voegele, M.D., Reliab Eng Syst Safe 122, 53 (2014).
20.Scheidt, C., Li, L., and Caers, J., editors, Quantifying Uncertainty in Subsurface Systems (Wiley & the American Geophysical Union, New York, N.Y., 2018).
21.Garrick, B.J. and Kaplan, S., Risk Anal 19, 903 (1999).
22.Reset Steering Committee, Reset of America’s Nuclear Waste Management Strategy and Policy (Stanford University, Stanford, CA, 2018).
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MRS Advances
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  • EISSN: 2059-8521
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