Holdup Data Analysis for Portsmouth Building X705

The Portsmouth Gaseous Diffusion Plant's Building X705 contains equipment for recovering uranium from other facility process equipment and materials. Measurements of holdup have been made at 825 locations within the building, including tanks, columns, pipes, and dissolution/leaching process equipment. These measurements have been made by the Applied Nuclear Technology Group of the Portsmouth Gaseous Diffusion Plant. Measuring holdup is strenuous and labor intensive, and it is desirable to reduce manpower requirements while maintaining some knowledge of facility holdup. The Los Alamos Safeguards Systems Group has helped analyze the data for total holdup and its uncertainty and developed a sampling plan to reduce the manpower requirements. This plan provides assurance that the process equipment has been flushed out, allows a statement of the total holdup and its uncertainty, and permits fewer measurements. The details of the data analysis and the sampling plan and its application to other facilities are discussed.