PNNL

Abstract

In recent years, the IAEA has pursued innovative techniques and an integrated suite of safeguards measures to address the verification challenges posed by advanced centrifuge technologies and the growth in capacity at gaseous centrifuge enrichment plants (GCEPs) [1; 2]. A prominent theme in the development of a new generation of safeguards measures for GCEPs is the use of permanently installed, unattended instruments that can provide continuous monitoring of facility activities, while also reducing the need for on-site inspections [3]. For example, the U.S. Support Program to the IAEA leads the development of an On-Line Enrichment Monitor (OLEM) [4; 5] and an Unattended Cylinder Verification Station (UCVS) [6]. OLEM units will provide continuous enrichment measurement for 100% of the declared gas flowing through unit header pipes, thereby improving the IAEA’s capabilities to verify operator declarations of enrichment. The OLEM concept requires an accurate determination of gas density in order to produce accurate enrichment calculations (Fig. 1). The current OLEM design assumes that this gas density is derived from a pressure transducer signal shared with the operator. The IAEA has expressed the desire for a technology that can independently and noninvasively measures gas density, in support of a next-generation OLEM design.