My research is in the field of environmental mineralogy and geochemistry, focusing on the fate and transport of metals and radionuclides in the environment. In particular, I am interested in the geochemical and biogeochemical processes that occur at mineral surfaces which can limit or promote contaminant transport in a range of surface environments. My research has ranged from applied characterization studies of uranium and copper speciation at the U.S. Department of Energy's Hanford Site, to fundamental studies of the processes by which uranium and strontium are sequestered at mineral surfaces.; Recent work has aimed at determining the mechanisms by which heavy metals or radionuclides can interact with complex mineral interfaces, in particular focusing on the formation of uranium-bearing nanoparticles.; This work is done by applying laboratory-based analytical and microscopy tools and synchrotron-based X-ray spectroscopic and scattering methods to investigate natural and model systems.

Current and future research interests include:

• Electron transfer reactions between aqueous contaminants and mineral surfaces
• Metal sorption and diffusion kinetics into mesoporous materials
• Laboratory- and field-scale testing of metal remediation and stabilization techniques