CONFIRMATORY MEASUREMENTS OF SPECIAL NUCLEAR MATERIAL

Confirmatory measurements have been used in nuclear material control and accountability programs since the inception of nuclear material control and accountability as a field of expertise. Nuclear materials lend themselves naturally to confirmatory type measurement, since the nuclear radiations from the material usually uniquely identify the material, are proportional to the quantity of nuclear material present, and can be measured using non-destructive arsay techniques (NDA) . ?,t the Savannah Fiver Plant (SRP) confirmatory measurements are employed by both the contractor and the U.S. Department of Energy (DOE) personnel to provide assurance that the Special Nuclear Material (SNM) in shipments, storage areas and in process areas is present in the quantity recorded and no diversion or loss of material has occurred. These measurements have ranged from simple measurements to verify that the material is radioactive to extensive m easurements to determine the isotopic content and quantity of SNM present. In order to obtain maximum benefit, from confirmatory measurements, the purpose of the measurement must first be defined and the technique of measurement carefully selected for the specific purpose in mind. This paper provides suggested guidelines for defining confirmatory measurements, reviews some typical applications and presents a specific example of confirmatory measurement techniques at SRP.