In-plant Measurements of Gamma-ray Transmissions for Precise K-edge and Passive Assay of Plutonium Concentration and Isotopic Fractions in Product Solutions

Russo, P. A.*; Asakura, Yoshiro*; Hsue, S. T.*; Kondo, Isao*; Sprinkle, J. K. Jr.*; Masui, J.*; Johnson, S. S.*; Shoji, J.*

An instrument based upon high-resolution -ray measurements has beentested for more than 1 year at the TokaiReprocessing Facility for determinationof plutonium concentration by K-edge absorption densitometry and for determination of plutonium isotopic fractions bytransmission-corrected passive -ray spectrometry. The nondestructive assay instrument was designed and built atLos Alamos National Laboratory for theTokai Advanced Safeguards Technology Exercise (TASTEX). It was used at Tokai forthe timely assay of more than 100 productsolution samples daring the TASTEX evaluations The results were compared tosolution samples during the TASTEXaluations. The results were compared toreference values obtained by conventionaldestructive analysis of these samples. The precision and accuracy of plutoniumconcentrations measured by the K-edgetechnique are shown to be with in 0.6% (1) in these applications. The precisionsand accuracies of the isotopic fractions. determined by these passive