SPENT FUEL SABOTAGE TESTING: DEPLETED URANIUM OXIDE AEROSOL RESULTS

We will summarize a multinational, multi-phase spent fuel sabotage test program that quantifies aerosol particles produced when the products of a high energy density device (HEDD) interact with and explosively particulate test rodlets that contain pellets of either surrogate materials or actual spent fuel. Testing has been underway for several years. This program provides source-term data that are relevant to plausible sabotage attack scenarios in relation to spent fuel transport and storage casks, and associated risk assessments. We present details and significant results from three Phase 3 tests performed using depleted uranium oxide pellets plus non-radioactive fission product dopants in surrogate spent fuel test rodlets. Measured aerosol results include: respirable fractions produced; amounts, nuclide content, and produced particle size distributions and morphology; measurements of volatile fission product species enhanced sorption – enrichment factors onto respirable particles; and, status on determination of the spent fuel ratio, SFR, needed for scaling studies. The DUO2 aerosol particle results are compared directly with our similar, recent Phase 2 results from cerium oxide ceramic pellet and fission product dopant surrogate test rodlets. We also provide a status review on preparations for the final Phase 4 in this program, tests using individual short rodlets containing actual spent fuel from U.S. PWR reactors, with both high- and lower-burnup fuel. The source-term data, aerosol results, and program design have been tailored to support and guide follow-on computer modeling of aerosol dispersal hazards and radiological consequence assessments. Test results also provide a further validation of vulnerability studies associated with spent nuclear fuels, and a basis for evaluating appropriate levels of transportation physical protection and safeguards requirements. This spent fuel sabotage, aerosol test program was performed primarily at Sandia National Laboratories, with support provided by both the U.S. Department of Energy and the Nuclear Regulatory Commission. It has significant input from, and is strongly supported and coordinated by both the U.S. and international program participants in Germany and France, as part of the International Working Group for Sabotage Concerns of Transport and Storage Casks (WGSTSC).