Advanced Integration Of Echem Safeguards Measurements

The Virtual Facility Distributed Test Bed (VFDTB) is a suite of computer models under development with the goal of demonstrating safeguards and security by design (SSBD). The VDFTB is comprised of a number of models that focus on such safeguard relevant areas as mass flow, mass balance calculation, facility and measurement models, and physical security modeling. The VDFTB has focused on applications to spent fuel recycling but the methodology and framework can be applied to other relevant nuclear facilities. The work in this paper is to assist both the VFDTB’s safeguards model, the electrochemical safeguards and security performance model (Echem-SSPM), and its three-dimensional facility model of a pyroprocessing facility. Both of these models are developed by the Sandia National Laboratories (SNL). The SSPM models the electrochemical reprocessing or pyroprocessing flow sheet and calculates mass movement as well as performs material balances. The SSPM also allows for the integration of both detector and process monitoring measurements. To assist the development of the three-dimensional facility model, we modeled the pyroprocessing process hot cell in Monte Carlo NParticle Code (MCNP) to map both its gamma and neutron radiation field with time. This model comprised of simplified models of pyroprocessing equipment and utilized radiation source terms calculated from mass movement data from the SSPM. In addition, we assisted the development of the SSPM by modeling the high dose neutron detector (HDND) for neutrons and a micro calorimeter detector for gammas both developed at Los Alamos National Laboratory (LANL) in MCNP. These models modeled the measurement and detection of potential diversion of nuclear material in a pyroprocessing uranium product ingot using material data calculated by the SSPM. In addition to ingot counting, the HDND model was simulated in the hot cell model to determine potential radiation signatures that could be monitored to generate conclusions about the movement of material with time and to calculate background radiation in the hot cell. The results of the MCNP simulations are to be integrated into the respective models in the VFDTB. Results and conclusions regarding these modeling campaigns in MCNP are presented in this paper.