INVENTORY CONFIRMATION MEASUREMENT AT LOS ALAMOS NATIONAL LABORATORY

Confirmation measurements of special nuclear materials (SNM) are conducted routinely at Los Alamos National Laboratory for inventory support. The main purpose of the measurement is to confirm the stated SNM contents of inventory items and to detect potential diversion or mislabeled materials. The Laboratory implemented the confirmation measurement as part of the inventory verification process in compliance with DOE Order addressing nuclear materials control and accountability. Three measurement techniques/methods were developed for assay of Pu and U bearing items. Acceptance/rejection criteria were established from data collected over several years. This paper describes the measurement techniques, the acceptance/rejection criteria and the resolution practices for items that fail the confirmation measurement tests. Sample data are presented for illustration of each technique.