has spent thirty years in the groundwater industry as a research geochemist (13 years at Pacific Northwest National Laboratory) and an applied geochemist (17 years) with environmental consulting firms. He has planned and executed numerous projects dealing with characterization of sites contaminated with organic and inorganic compounds, and has been involved with the design and implementation of remedial measures for those sites. Since 1984, he has taught professional development classes on groundwater geochemistry and geochemical modeling to over 3,000 students. These classes have primarily been offered through the National Ground Water Association, although additional classes have been given to federal and state regulatory agencies, chemical and oil/gas companies, and consulting firms. He is the author of Groundwater Geochemistry published by CRC Press in 1997.