THE RESULTS OF THE NLO ERROR PROPAGATION EXERCISE

The successful conclusion of the Error Propagation Exercise, started 2 years ago at NLO, Inc.'s Feed Materials Production Center, Fernald, Ohio, was reached when a statistically based LEID was determined in a controlled balance area, processing low enriched uranium materials. The three-month test demonstrated that it is possible even in a high-throughput bulk processing facility to collect and process all data necessary for computation of a rigorously determined LEID without interference with production and without significant cost increases. The exercise further demonstrated that much of the data necessary are already collected for other routine uses (e.g., production control, measurement quality control, etc.) so that only a modest increase in data collection is necessary. The automated data collection system developed showed that the additional data can be collected quickly, accurately, and relatively cheaply using readily-available commercial hardware. The benefits of error propagation in terms of increased confidence in nuclear materials safeguards are clear; plans have been developed to extend error propagation to all the enriched uranium processing areas of the Feed Materials Production Center.