Integrated five station nondestructive assay system for the support of decontamination and decommissioning of a former plutonium mixed oxide fuel fabrication facility

The goal of a safe, efficient and economic decontamination and decommissioning of plutonium facilities can be greatly enhanced through the intelligent use of an integrated system of nondestructive assay equipment. We have designed and fabricated such a system utilizing five separate NDA stations integrated through a single data acquisition and management personal computer-based controller. The initial station utilizes a passive neutron measurement to determine item Pu inventory to the 0.1 gm level prior to insertion into the decontamination cell. A large active neutron station integrated into the cell is used to measure decontamination effectiveness at the 10 nci/gm level. Cell Pu buildup at critical points is monitored with passive neutron detectors. An active neutron station having better than 1 mg Pu assay sensitivity is used to quantify final compacted waste pucks outside the cell. Bulk Pu in various forms and isotopic enrichments is quantified in a combined passive neutron coincidence and high resolution gamma ray spectrometer station outside the cell. Item control and Pu inventory are managed with bar code labeling and a station integrating algorithm. Overall economy is achieved by multiple station use of the same expensive hardware such as the neutron generator