OPTIMIZING NEAR REAL TIME ACCOUNTABILITY FOR REPROCESSING

Near Real Time Accountability (NRTA) of actinides at high accuracy in reprocessing plants has been a long sought-after goal in the safeguards community. Achieving this goal is hampered by the difficulty of making accurate measurements in the reprocessing environment, equipment cost, and impact to plant operations. Thus the design of future reprocessing plants requires an optimization of different approaches. The Separations and Safeguards Performance Model (SSPM), developed at Sandia National Laboratories, was used to evaluate two different NRTA strategies in a UREX+ reprocessing plant. The first strategy examined the incorporation of additional actinide measurements of internal plant vessels, while the second examined integration with process monitoring data. Preliminary results show that the first strategy can improve the timeliness of detection of abnormal events; however, the overall measurement uncertainty will increase and the cost and burden to the operator is expected to be significant. The second strategy can provide the same benefit using instrumentation that is already part of the plant design. The modeling results for the two different NRTA options under various material loss conditions are discussed.