Interfacial processes have a central role in many reactions and phenomena in the water environment, including mineral weathering, element cycling in the hydrosphere, particle stability in surface waters, subsurface transport of chemical species, bioavailability of nutrient and toxicant chemicals, and chemical residence times in environmental systems. This symposium will bring together scientists and engineers studying the fundamental interfacial processes involved in such phenomena, and the effects of these processes in the water environment.