Lawrence Berkeley National Laboratory

Microorganisms play an important role in the immobilization and mobilization of actinides in aquifers and subsurface environments.This talk will present several detailed examples of the interaction of aerobic soil bacteria with uranium and plutonium. Details of the nature of the bacterial functional groups involved in the interfacial actinide interaction process will be reported. Based on time-resolved laser-induced fluorescence spectroscopy (TRLFS) and synchrotron X-ray absorption spectroscopy (XANES and EXAFS) studies, molecular-level mechanistic details of the different interaction processes will be discussed. Complexation studies on bacterial surface model compounds with curium will be reported. Areas of this emerging field in actinide research will be outlined where additional information and integrated interdisciplinary research is required.