Facility Safety Assessment

Safety Documentation and Support

The Argonne Waste Management Operations (WMO) Department operates four nuclear facilities engaged in the treatment, storage, and disposal of hazardous wastes in support of the Argonne research mission. Engineering Research (ER) has been frequently engaged to support those waste management functions. Among the most important of those support tasks were the preparation of safety analysis reports for the nuclear facilities, the conduct of unreviewed safety question (USQ) determinations for proposed changes in operations and procedures, the review of critical WMO documents to assure their compliance with Department of Energy (DOE) requirements, and assessments and preparation of safety documentation for a project to characterize and certify transuranic waste for shipment to a permanent government repository.

The experience of ER staff in such has been used by other entities within the DOE Laboratory system with upgrade of safety analysis reports and accident assessments.

Fuel Conditioning Facility (FCF) Support

FCF operations are regulated by the DOE primarily by requiring compliance with the facility final safety analysis report (FSAR) and its technical safety requirements (TSRs). Since FCF commissioning, a number of issues impacting FCF operating efficiency have arisen that required technical support from the ER staff at Argonne. The following are just two examples of such issues.

A major effort that is intermittently ongoing involves assessing the ignition potential of various materials involved in the spent-fuel treatment process. This is important because both the FSAR and the TSRs address an accident scenario in which the inert atmosphere of the main processing cell is replaced with air, resulting in the ignition and burning of certain radioactive materials and their ultimate release to the environment via a filtered-exhaust system. In this effort, it was determined that a significant number of materials could be removed from the material-at-risk (MAR) category, the designation of those materials that had been presumed to ignite under the hypothesized accident conditions. As a result, FCF operations were simplified because of the reduced need for associated precautions under certain operating conditions.

The Cathode Processor (CP), essentially a high-temperature furnace, is an important piece of FCF equipment that is one step in the multi-step treatment process. The throughput of spent fuel in the process depends critically on the CP operation. In some processing scenarios the CP represented a bottleneck in processing due significantly to the time associated with the cooldown of the CP to temperatures at or below 150 C before it could be opened. Whether the CP could be opened at higher temperatures was the critical issue because of exposure of the nearest cell shielding window to high temperature, possibly damaging the window and requiring a costly and lengthy shutdown. It was demonstrated that the window would not be damaged if the CP were opened at temperatures as high as 400 C.

Last Modified: Thu, April 21, 2016 4:58 AM