Security, Safety, and Safeguards (3S) Risk Analysis for Small Modular Reactors

Small modular reactors (SMR) are increasingly emerging as efficient and effective methods to meeting growing energy demands worldwide. Because the global community has a growing aversion to cost and schedule overruns traditionally associated with the current fleet of commercial nuclear power plants (NPP), SMRs are attractive, viable alternatives because they offer a significant relative cost reduction to current-generation NPPs. In addition, popular claims for SMRs indicate certain benefits for safety and security that seemingly challenge long-established regulatory regimes and procedural norms. Yet, the new physical layouts, procedural design, and increased digitization of proposed SMRs may challenge traditional approaches to nuclear security, safety, and safeguards (3S)-related risk. Research emerging from Sandia National Laboratories (Sandia) offers three useful conclusions for evaluating risk complexity in safety, safeguards, and security of nuclear fuel cycle activities. First, integrated 3S approaches can help identify gaps, interdependencies, conflicts, and leverage points across traditional safety, security, and safeguards analysis techniques. Second, including the interdependencies between safety, safeguards, and security better aligns with real-world operational uncertainties and better describes the risk complexity associated with multi-model, multi-jurisdictional systems. Third, risk mitigation strategies resulting from integrated 3S risk assessments can be designed to better account for interdependencies not included in independent “S” assessments. Recent Sandia research has applied these conclusions to investigating risk complexity in SMRs. More specifically, this research provides technically rigorous analysis of the safety, safeguards, and security risks of SMR technologies and an introduction to a systems-theoretic approach for exploring interdependencies between the technical evaluations. This paper will first offer a summary of the challenges and insights identified in the current literature on SMR safety, security, and safeguards. Next, the SMR safety, safeguards, and security technical evaluations are summarized. Finally, a preliminary integrated 3S technical evaluation is offered, followed by implications for 3S analysis of SMRs. By extension, this framework could be used to evaluate SMRs as a “systems-level” whole to better characterize, evaluate, and manage increasing risk complexity. (SAND2019-0719A)