Available online at www.sciencedirect.com Nuclear Engineering and Design 238 (2008) 1093–1099 Development of severe accident management guidance (SAMG) for the Canadian CANDU 6 nuclear power plants Thinh Nguyen a,∗ , Raj Jaitly a , Keith Dinnie b , Ron Henry b , Don Sinclair c , David J. Wilson c , Michael O’Neill d a Atomic Energy of Canada Limited (AECL), 2251 Speakman Drive, Mississauga, Ontario, Canada L5K 1B2 b Nuclear Safety Solutions Limited (NSS), 700 University Avenue, Toronto, Ontario, Canada M5G 1X6 c New Brunswick Power Nuclear, P.O. Box 600, Lepreau, New Brunswick, Canada E5J 2S6 d Ontario Power Generation (OPG), 889 Brock Road, Pickering, Ontario, Canada L1W 3J2 Received 5 August 2006; received in revised form 1 June 2007; accepted 20 August 2007 Abstract This paper discusses the severe accident management guidance (SAMG) development process undertaken for the Canadian CANDU 6 nuclear power plants (NPPs); the customization process of the generic CANDU SAMG for the Point Lepreau NPP is presented. Examples of severe accident management (SAM) guidelines related to containment pressure control are included in this paper. This paper also provides an overview summary of the severe accident analysis program at Atomic Energy of Canada Limited (AECL) that complements the SAM guidelines development process for the CANDU 6 NPPs in Canada. These analyses provided insights into the accident progression and basis to develop the SAM guidelines. Crown Copyright © 2007 Published by Elsevier B.V. All rights reserved. 1. Introduction The CANDU ®1 reactors contain both inherent and engi- neered safety features that make them particularly resistant to severe accidents. However, should a severe accident occur despite these safety features, procedural lines of defense are available in the accident management (AM) program. The emergency operating procedures (EOPs) or similarly named documents, which are developed from the extensive and com- prehensive set of accident analyses, provide adequate coverage for design basis accidents. Because of the Canadian regulatory requirement to cover dual failure accidents (Hurst and Boyd, 1972) (e.g., loss of coolant accident coupled with unavailability of the emergency core cooling system) as part of the design basis set for the CANDU reactor design, the symptom-based EOPs also cover accidents that would be considered severe accidents elsewhere in the world. ∗ Corresponding author. E-mail address: nguyenth@aecl.ca (T. Nguyen). 1 CANdian Deuterium Uranium (CANDU) is a registered trademark of AECL. Recently, the Canadian nuclear industry has agreed that there is a need to review and, where necessary, develop and implement appropriate additional measures to mitigate the effects of events beyond the current design basis. The development of severe acci- dent management guidance (SAMG) for the Canadian nuclear power generation industry represents an important step in the evolution of nuclear safety assurance in Canada (Fluke et al., 2005). This Canadian SAMG development task is being under- taken by a consortium consisting of Atomic Energy of Canada Limited (AECL) and Nuclear Safety Solutions Limited (NSS), under contract with the CANDU Owners’ Group (COG) on behalf of the Canadian nuclear utilities. The SAMG development for the domestic CANDU plants began with the development of a generic set of guidelines and basis documents covering all three general types of CANDU designs in Canada: Pickering (multi-unit stations), Bruce/Darlington (multi-unit stations), and CANDU 6 (single- unit station). The general SAMG approach developed by the Westinghouse Owner’s Group (WOG) was followed, suitably modified to take into account the unique CANDU design fea- tures. The second phase of the SAMG development was the customization of the station specific SAMG for all domestic CANDU plants based on the generic SAMG. This paper pro- 0029-5493/$ – see front matter. Crown Copyright © 2007 Published by Elsevier B.V. All rights reserved. doi:10.1016/j.nucengdes.2007.08.005