Investigating the Electrodeposition of Plutonium and Curium for Safeguarding the Electrorefiner

This research investigated the electrochemical deposition behavior of plutonium (Pu) and curium (Cm) for safeguarding the electrorefiner (ER) in a pyroprocessing facility. The main goal of this investigation was to evaluate the feasibility of using a safeguards concept called the neutron balance method to account for Pu in the ER. The neutron balance method relies on a known Pu/Cm ratio and measures neutrons from Cm-244 coming into and leaving a unit operation to track Pu. The application of the neutron balance approach for pyroprocessing facilities requires that Pu and Cm remain together in all extraction, product recovery, and waste streams. The electrochemical deposition experiments conducted, using a surrogate system of Tb and Gd, revealed that the Tb to Gd ratio was inconsistent between the electrolyte and the cathode deposit under different electrolyte concentrations. The Enhanced REFIN with Anodic Dissolution (ERAD) computer simulations of the same Tb/Gd surrogate system also found that the Tb to Gd ratio varied. ERAD simulations of a large-scale pilot facility also revealed that the Pu to Cm ratio was not constant between the electrolyte salt and the metal deposit when Pu co-deposition occurs. The safeguards assessment concluded that the neutron balance method was an insufficient safeguards approach for the eletrorefiner and working under the assumption that the Pu/Cm ratio was invariable resulted in the loss of significant quantities of special nuclear material (SNM) after processing only a few batches

Evolution of Safeguards - An Expert-driven Approach to Acquisition Path Analysis

The IAEA’s Department of Safeguards has embarked on an evolutionary process to more fully develop and apply the State-Level Concept (SLC) for safeguards implementation. This concept makes use of all safeguards-relevant information available in order to focus and prioritize its safeguards activities for a State. A key component is the development of a State-level Approach (SLA) which consists of analyzing acquisition paths, establishing and prioritizing technical objectives, and identifying applicable safeguards measures. The Next Generation Safeguard Initiative of the National Nuclear Security Administration, Office of Nonproliferation and International Security, has supported LANL's assessment of alternatives for SLA development. Our proposed methodology is comprised of three activities: network modeling, network analysis, and strategic assessment. The network modeling step assesses and formalizes the State’s nuclear capabilities in terms of plausible proliferation paths. The network analysis step gives a ranking of paths in terms of their attractiveness under various assumptions. Finally, the strategic assessment evaluates the State’s proliferation alternatives given a set of derived technical objectives and the implementation of related safeguards measures. In this paper, we examine a hypothetical State model to test our methodology’s performance. In this context, we identified and prioritized the hypothetical State’s acquisition paths according to notional proliferation strategies. State Specific Factors were examined in terms of their impact on path priorities. We examined methods for determining technical objectives contingent upon meeting designated performance targets and examined State-wide safeguard performance. This paper represents the most recent iteration of LANL’s SLA development approach and the assessment of its applicability to the IAEA’s State-level Concept

Acquisition Path Analysis Quantified – Shaping the Success of the IAEA’s State-level Concept

The IAEA’s Department of Safeguards has embarked on an evolutionary process to more fully develop and apply the state-level concept (SLC) for safeguards implementation. In an attempt to direct safeguards to areas of significant proliferation concerns within a state, this concept makes use of all safeguards-relevant information available in order to focus and prioritize its safeguards activities for a state.A key component is the development of a customized safeguards approach for an individual state. Developing these state-level approaches consists of analyzing acquisition paths, establishing and prioritizing technical objectives, and identifying applicable safeguards measures. The paper presents a methodology to accomplish this process based on a threestep-approach: network modeling, network analysis, and strategic assessment.The network modeling step assesses and models the state’s nuclear capabilities as well as other state-specific factors concerning relevant proliferation scenarios. The network analysis step gives a ranking of all plausible acquisition paths including a visualization of the paths. Finally, the strategic assessment step evaluates the state’s proliferation and compliance options as well as the IAEA’s set of technical objectives and subsequent safeguards measures. In this paper, a hypothetical state model was developed in order to test the methodology’s performance. Therefore, an Excel spreadsheet with all necessary state-level factors was created. Afterwards, a Python software module based on graph theoretical algorithms was applied to produce a comprehensive list of ranked acquisition paths including their visualization. The following step of the strategic evaluation is mainly based on the concept of the Nash equilibrium resulting in a stable combination of the state’s and the IAEA’s strategies. This formal and automatic procedure offers the advantage of gaining results in a comprehensive and non-discriminative manner.Besides presenting and discussing the methodology in detail, results from an example case study will also show how this process could be carried out in practice. Furthermore, the problem of how to determine the model parameter “detection probability” will be discussed. The paper ends with conclusions and an outlook on planned future work in this area

Evolution of Safeguards - What Can Formal Acquisition Path Analysis Contribute?

The IAEA’s Department of Safeguards has embarked on an evolutionary process to more fully develop and apply the State-level concept for safeguards implementation. In an attempt to direct safeguards to areas of greatest proliferation risk, this concept makes use of all safeguards-relevant information available in order to focus and prioritize its safeguards activities for a State.A key component is the development of a State-level Approach which consists of analysing acquisition paths, establishing and prioritizing technical objectives, and identifying applicable safeguards measures. The methodology to accomplish this is based on a three-step-approach: network modeling, network analysis, and strategic assessment. The network modeling step assesses and formalizes the State’s nuclear capabilities as well as other state-specific factors concerning relevant proliferation scenarios. The network analysis step gives a ranking of all plausible acquisition paths including a visualization of the paths. Finally, the strategic assessment evaluates the State’s proliferation and compliance options as well as the IAEA’s set of technical objectives and subsequent safeguards measures.In this paper, a hypothetical State model was developed in order to test the methodology’s performance. Therefore, an Excel spreadsheet with all necessary state-level factors has been created. Afterwards, a Python software module based on graph theoretical algorithms was applied to produce a comprehensive list of ranked acquisition paths including their visualization. The following step of the strategic evaluation is mainly based on the concept of the Nash equilibrium resulting in a stable combination of the State’s and the IAEA’s strategies. This formal and automatic procedure offers the advantage of gaining results in a comprehensive and non-discriminative manner