EVALUATION OF ENVIRONMENTAL SAMPLING FOR SAFEGUARDS BY ABACC

In June 1998, the U.S. Department of Energy agreed to provide assistance to the Brazilian- Argentine Agency for Accounting and Control of Nuclear Materials (ABACC) in initiating a project to evaluate environmental sampling capabilities at laboratories in Argentina and Brazil. During the initial planning meeting for the exercise, representatives from all of the participating laboratories were briefed on how the exercise would be managed, and on key aspects of the analytical approach necessary to successfully analyze low-level environmental samples. In particular, the stringent requirements for sample preparation and contamination control were covered in detail. The use of isotope dilution mass spectrometry for the determination of total uranium was also discussed. Arrangements were made with the International Atomic Energy Agency (IAEA) to provide sets of cotton swipe samples prepared from the same materials used in the IAEA environmental sampling program. Each swipe was loaded with approximately 300-ng of one of the certified uranium reference materials developed by the Agency to evaluate the performance of the IAEA Network of Analytical Laboratories (NWAL). Three reference materials with uranium isotopic compositions close to natural were used. Blank swipes were also included in each set. The exercise was completed in May 1999. Results from the exercise and future plans will be covered in this presentation.