Passive and Active Measurement of SNM

In many government and private nuclear fuels facilities, waste containing SNM is packaged in large drums. Future facilities will generate large volumes of low SNM content waste. Economics of small container assay relative to large drum assay is addressed, and the question of contribution of drum assay to LEMUF is investigated. The measurement alternatives for 235U and 239Pu in large gallon drums and their accuracies are reviewed. Techniques reviewed include passive gamma-ray and neutron assay, active neutron assay, and bremsstrahlung assay. The influence of fission products on the measurements is considered.