New Insight into the Mechanism of Plutonium Transport in the Environment
The potential migration of plutonium in the environment is a concern at DOE sites such as the Hanford Nuclear Reservation and the Nevada Test Site, as well as an issue in nuclear waste disposal for nuclear energy development. Using a number of transmission electron microscopy techniques Lawrence Livermore National Laboratory researchers and collaborating Clemson University scientists have provided important new understanding of the formation and the biogeochemical mechanisms controlling plutonium migration. Once thought immobile in the subsurface, it has been recently recognized that plutonium is capable of being transported with the colloidal faction of groundwater. The researchers examined the interaction of plutonium nanocolloids with environmentally relevant minerals such as iron-containing goethite and silicon-containing quartz. The studies revealed the molecular basis of potential binding through epitaxial growth between the plutonium nanocolloids and colloid goethite that may be a possible mechanism for enhanced plutonium transport. The results improve our understanding of how molecular-scale behavior at the mineral-water interface may facilitate transport of plutonium at the field scale, providing important molecular-level input to improve contaminant transport models and the prediction of plutonium behavior.
Powell, B. A., Z. Dai, M. Zavarin, P. Zhao, and A. B. Kersting. 2011. “Stabilization of Plutonium Nano-Colloids by Epitaxial Distortion on Mineral Surfaces,” Environmental Science and Technology 45, 2698–2703. DOI:dx.doi.org/10.1021/es1033487.