Kyle J. Bunch, Mark Jones, Pradeep Ramuhalli, Jacob Benz, Laura Schmidt Denlinger, "Supporting Technology for Chain of Custody of Nuclear Weapons and Materials Throughout the Dismantlement and Disposition Processes," Science & Global Security 22, no. 2 (2014): 111-134
Verification technologies based upon electromagnetics and acoustics could potentially play an important role in fulfilling the challenging requirements of future verification regimes. For example, researchers at the Pacific Northwest National Laboratory (PNNL) have demonstrated that low frequency EM signatures of sealed metallic containers can be used to rapidly confirm the presence of specific components on a "yes/no" basis without revealing classified information. PNNL researchers have also used ultrasonic measurements to obtain images of material microstructures which may be used as templates or unique identifiers of treaty accountable items (TAIs). Such alternative technologies are suitable for application in various stages of weapons dismantlement and often reduce or eliminate classified data collection because of the physical limitations of the method. In such cases the need for an information barrier to prevent access to classified data is potentially eliminated, thus simplifying verification scenarios. As a result, these types of technologies may complement traditional radiation-based verification methods for arms control.This article presents an overview of several alternative verification technologies that are suitable for supporting a future, broader and more intrusive arms control regime that spans the nuclear weapons dismantlement lifecycle. The general capabilities and limitations of each verification modality are discussed and example technologies are presented. These technologies are relevant throughout a potential warhead monitoring regime, from entry into chain of custody (i.e., establishing confidence in the authenticity and integrity of the warhead) to dismantlement and final material disposition (i.e., maintaining confidence that chain of custody has not been broken).