Year
2001
Abstract
Effective international safeguards approaches for gas centrifuge plants require the capability to verify the absence of any undeclared feed and withdrawal activities in the cascade areas of the plant. If visual observation of processing areas cannot provide credible assurance, because of facility construction characteristics (e.g., shrouding of the centrifuges with opaque panels), additional measurement methods are necessary. The United States is providing technical assistance to the International Atomic Energy Agency (IAEA) to develop and evaluate inspection tools for such circumstances. Measurement methods that use a combination of nondestructive assay measurement techniques have been developed to identify moderately enriched uranium and shielding material that potentially could be secluded within the confines of the cascade hall. A small mockup of a section of cascade hall was fabricated to conduct parametric testing. These tests determined the detection capability of selected measurement methods for concealed containers of moderately enriched uranium. Test variables included container orientation and position, shielding thickness, and shielding type. For some of the tests, measurement personnel were not informed of the test variable values (i.e., the position and shielding of the item).