Viability Study for an Unattended UF₆ Cylinder Verification Station: Phase I Final Report

Technical Report · Tue May 31 00:00:00 EDT 2016

DOI:https://doi.org/10.2172/1333456· OSTI ID:1333456

Smith, Leon E. ^[1]; Miller, Karen A. ^[2]; Garner, James R. ^[3]; Branney, Sean ^[4]; McDonald, Benjamin S. ^[1]; Webster, Jennifer B. ^[1]; Zalavadia, Mital A. ^[1]; Todd, Lindsay C. ^[1]; Kulisek, Jonathan A. ^[1]; Nordquist, Heather ^[2]; Deshmukh, Nikhil S. ^[1]; Stewart, Scott ^[3]

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1. Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
4. Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

In recent years, the International Atomic Energy Agency (IAEA) has pursued innovative techniques and an integrated suite of safeguards measures to address the verification challenges posed by the front end of the nuclear fuel cycle. Among the unattended instruments currently being explored by the IAEA is an Unattended Cylinder Verification Station (UCVS) that could provide automated, independent verification of the declared relative enrichment, ²³⁵U mass, total uranium mass and identification for all declared UF₆ cylinders in a facility (e.g., uranium enrichment plants and fuel fabrication plants). Under the auspices of the United States and European Commission Support Programs to the IAEA, a project was undertaken to assess the technical and practical viability of the UCVS concept. The US Support Program team consisted of Pacific Northwest National Laboratory (PNNL, lead), Los Alamos National Laboratory (LANL), Oak Ridge National Laboratory (ORNL) and Savanah River National Laboratory (SRNL). At the core of the viability study is a long-term field trial of a prototype UCVS system at a Westinghouse fuel fabrication facility. A key outcome of the study is a quantitative performance evaluation of two nondestructive assay (NDA) methods being considered for inclusion in a UCVS: Hybrid Enrichment Verification Array (HEVA), and Passive Neutron Enrichment Meter (PNEM). This report provides context for the UCVS concept and the field trial: potential UCVS implementation concepts at an enrichment facility; an overview of UCVS prototype design; field trial objectives and activities. Field trial results and interpretation are presented, with a focus on the performance of PNEM and HEVA for the assay of over 200 “typical” Type 30B cylinders, and the viability of an “NDA Fingerprint” concept as a high-fidelity means to periodically verify that the contents of a given cylinder are consistent with previous scans. A modeling study, combined with field-measured instrument uncertainties, provides an assessment of the partial-defect sensitivity of HEVA and PNEM for both one-time assay and (repeated) NDA Fingerprint verification scenarios. The findings presented in this report represent a significant step forward in the community’s understanding of the strengths and limitations of the PNEM and HEVA NDA methods, and the viability of the UCVS concept in front-end fuel cycle facilities. This experience will inform Phase II of the UCVS viability study, should the IAEA pursue it.

• Research Organization: Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1333456
• Report Number(s): PNNL-25395; DN4001030; TRN: US1700765
• Country of Publication: United States
• Language: English

Related Subjects

98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL PROTECTION
42 ENGINEERING
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
URANIUM HEXAFLUORIDE
VERIFICATION
URANIUM
CYLINDERS
ISOTOPE SEPARATION PLANTS
URANIUM 235
ENRICHMENT
FUEL FABRICATION PLANTS
MASS
PERFORMANCE
DEFECTS
DESIGN
EVALUATION
NONDESTRUCTIVE ANALYSIS
IMPLEMENTATION
IAEA SAFEGUARDS
SENSITIVITY
SIMULATION
IDENTIFICATION SYSTEMS
FEASIBILITY STUDIES