Toxic contaminants and naturally occurring substances found in the subsurface can exist in multiple phases, and undergo complex reactions including biodegradation. A comprehensive and quantitative understanding of the processes controlling the fate and transport of subsurface contaminants is necessary to develop policies and strategies for managing water-quality conditions in different land use and environmental settings. Numerical models that simulate flow, transport, and reactions are useful tools for understanding the fate of chemicals in the subsurface when used in conjunction with field and laboratory studies. The research efforts of this project consider flow and chemical behavior in the saturated and unsaturated zones. We cover a broad range of contaminants including petroleum hydrocarbons, actinides, chlorinated solvents, creosote compounds, and agricultural chemicals. Using the same basic techniques, we also conduct research on the role of groundwater flow in transporting heat and chemicals along active faults. Members of this project develop and use numerical models, conduct field studies, and perform laboratory experiments, to understand flow, transport, and reactions of chemicals in the subsurface. These chemicals can include anthropogenic contaminants as well as naturally occurring species such as nutrients, terminal electron acceptors, reactive minerals and surfaces.
