Collaborative study of an anion exchange method for the determination of trace plutonium in water

Abstract

A single-laboratory evaluation and an interlaboratory collaborative study were made of a method for determining plutonium in water. The method was written for the analysis of one-liter samples and involves coprecipitation, acid dissolution, anion exchange, electrodeposition, and alpha pulse height analysis. After the single-laboratory evaluation of the selected method, four samples were prepared for the collaborative study: two river-water samples, a substitute ocean water sample, and sample containing sediment. These samples contained plutonium-239 and plutonium-238 at concentrations ranging from 0.42 to 28.9 dis/min/liter. In the collaborative study standard deviations of plutonium concentrations ranged from 5 to 13%. In three cases, standard deviations agreed with those expected from counting statistics. It is believed that hydrolysis occurred in the river water samples resulting in errors greater than those expected from counting statistics.