Modern NDA Needs at the Savannah River Site

As the missions within the nuclear weapons complex change, so do the accountability measurement needs. Non-Destructive Assay (NDA) measurements have played a key role in accounting for special nuclear materials (SNM), and as time goes on, more and more reliance is made on this type of measurement. Key questions NDA instrument designers ask are: Which isotopes are of interest?; What matrix are they in?; What other isotopes are present?; What container configuration will it be measured through?; What precision and accuracy is required?; What level of resolution is required?. At the Savannah River Site (SRS) the desire to make direct measurements of SNM isotopes has prompted the evaluation to these and other questions. This paper will outline the current NDA needs at SRS. The discussion includes the types of materials that require measurement including the very difficult waste measurements. The special challenges associated with these measurement efforts will also be discussed.