DESC0024948

Reducing physical protection costs is a key element in making nuclear energy a viable source for the public. Advanced and small reactors must reduce their expected physical protection costs before the construction of an actual production reactor begins. Advanced and small reactors have the benefit of exploring new approaches and technologies to enhance physical protection and reduce the operational cost associated with that protection that can be incorporated into the design of the plant itself. These reactor designs typically include a safer operating envelope and require greater amounts of time to reach critical danger points. It is also expected that plants based on this type of design will have a smaller footprint that may allow them to rely upon technology or physical plant structure differently from existing nuclear power plants. Advanced and small reactors face a contrasting challenge in that there is no operating site that can be treated as a baseline when measuring the performance of the physical protection systems. Modeling and simulation tools provide the capability to explore different designs, operating procedures, and technologies without the existence of a physical site. These tools are a useful resource when studying the effectiveness of various protection measures so that the operating costs of those measures can be included in decisions for the overall design and implementation plan. RhinoCorpsĺ Simajin/Vanguard tool is a proven modeling and simulation tool for analyzing system effectiveness of physical security systems at DOE and NRC-licensee nuclear facilities including analysis of security for the design package for a small modular reactor. Simajin/Vanguard provides an environment for the representation of a high-fidelity three-dimensional model of the plant, its security systems, and the security personnel in which those elements can be stressed using hypothetical attack scenarios. Advanced and small modular reactors stand to benefit from different types of operator actions that might be applied in the early stages of an attack as well as after elements of target sets have been compromised that could potentially prevent offsite release of radioactive contamination. Although Simajin/Vanguard can effectively represent the security response it cannot directly evaluate the thermal-hydraulic conditions of the reactor. Connecting Simajin/Vanguard to an external model that can simulate the response of a reactor given the timing of adversary actions and corresponding operator actions will provide a better understanding of the consequences given an attack. This could potentially support analysis tools to better define the safe operating range of the reactor during and after a security event. Being able to effectively quantify the safe operating range for the new design could have a direct effect on security costs. The potential to reduce the number of target sets or to increase the number of target set elements in a target set are both beneficial to security. This research is needed to support better techniques for integrating security modeling and simulation tool output with simulation tools that evaluate how the reactor will perform.