A Robust and Flexible Design for Gas Centrifuge Enrichment Plant Unattended On-Line Enrichment Monitoring: An OLEM Collection Node Infrastructure

Oak Ridge National Laboratory has engineered a passive on-line enrichment monitor (OLEM) to continuously measure 235U gamma-ray emissions from the UF6 gas flowing through a unit header pipe of a gas centrifuge enrichment plant (GCEP) as a component of the International Atomic Energy Agency’s (IAEA’s) new generation of technology to support GCEP safeguards. From a safeguards perspective, OLEM can provide early detection of a GCEP being misused for production of highly enriched uranium (HEU) although it would not detect directly the isolation and use of a cascade within the production unit to produce HEU. OLEM may also reduce the number of samples collected for destructive assay and, if coupled with load cell monitoring, could support isotope mass balance verification and unattended cylinder verification. An earlier paper presented the OLEM concept and described how previous modeling studies and field measurements helped confirm the viability of a passive OLEM for meeting IAEA objectives and to support the development of performance targets. Phase I of the United States Support Program OLEM project completed a preliminary hardware, software, and communications design. In collaboration with Los Alamos National Laboratory, Phase II will build field prototypes, test them in controlled laboratory settings, and later test them at an operational facility. A separate paper described the early design process for OLEM field prototypes, emphasized the use of commercial off-the-shelf components in the OLEM collection node and summarized the OLEM collection node data security provisions. This paper discusses a secure and redundant network of OLEM collection nodes, auxiliary detection units, and supporting junction boxes distributed throughout a facility for monitoring enrichment on product, tails, and possibly feed-unit header pipes; the purpose and capability of the built-in IAEA Electronic Optical Sealing System network gateway; and a network approach for obtaining reliable and authenticated pressure measurements.