Development and evaluation of methods for safeguards use of solution monitoring data

摘要

This report describes the effort to develop, implement, and evaluate data analysis methods for solution-monitoring measurements in the plutonium nitrate storage at the Tokai Reprocessing Plant (TRP). The intent is to address TRP-specific issues to some extent, as well as to anticipate the data analysis needs at future reprocessing plants (especially the new Rokkasho reprocessing plant (RRP)) in Japan. The essential difference between a plant like TRP and a more modern plant like RRP is that one expects more and better instrumentation in the tanks in a modern plant. Because the TRP solution monitoring hardware is scheduled to be upgraded, the authors de-emphasized the effort to handle information-poor plants like TRP. This report mostly describes the analysis methods and software for finding and identifying all key tank events. To a large extent they have to experiment with several candidate methods for implementing their analysis objectives. Therefore, they chose to use a prototyping software system called S-PLUS, which is an object-oriented statistical programming and graphics package. The intent is to eventually implement selected portions of their current solution-monitoring toolkit in a more robust and user-friendly system. The authors describe their current software system as being far more than they needed for their own in-house use (menus are provided for the user who doesn't want to type any S-PLUS commands), but less than is needed for a fieldable system. Mostly as a result of working on this project, they have come to conclude that solution monitoring is a potentially very valuable asset to nuclear safeguards at a modern reprocessing plant.