Kate Campbell is a biogeochemist with the National Research Program of the Water Mission Area, U.S. Geological Survey, Boulder, Colorado. She received a B.S. in chemistry from Georgetown University and an M.S. and Ph.D. in environmental engineering from the California Institute of Technology. She worked on bioremediation of uranium for her postdoctoral work at the USGS in Menlo Park, California before joining the chemical modeling of acid waters group. Her research focuses on abiotic and biotic redox chemistry of natural waters, including acid rock drainage, geothermal waters, and groundwaters; biogeochemical modeling of kinetically controlled processes, especially iron, arsenic, antimony, and uranium redox chemistry; coupled biotic-abiotic controls on microbial ecology in geothermal and mining environments; and novel sampling techniques for redox processes for field application.