Radiochemical determination of Am-241 and Pu(alpha) in environmental materials

Americium-241 and plutonium determinations will become of greater importanc e over the coming decades as Cs-137 and (PU)-P-241 decay, The impact of Cs- 137 On environmental chronology has been great, but its potency is waning a s it decays and diffuses. Having Am-241 and Pu as unequivocal markers for t he 1963 weapon fallout maximum is important for short time scale environmen tal work, but a fast and reliable procedure is required for their separatio n. The developed method described here begins by digesting samples using a lithium berate fusion although an aqua regia leachate is also effective in many instances. Isolation of the Am and Pu is then achieved using a combina tion of extraction chromatography and conventional anion exchange chromatog raphy, The whole procedure has been optimized, validated, and assessed for safety. The straightforwardness of this technique permits the analysis of l arge numbers of samples and makes Am-241-based techniques for high-resoluti on sediment accumulation rate studies attractive. In addition, the techniqu e can be employed for the sequential measurement of Pu and Am in environmen tal surveillance programs, potentially reducing analytical costs and turn-r ound times.