Philip L Hageman has been a Research Physical Scientist at the US Geological Survey for more than 25 years. His research interests include a broad variety of interdisciplinary geochemistry studies incorporating geology, the environment, issues affecting human health, and disaster response. He has experience in characterization and assessment of the mobility of constituents from metal mining waste, varied geological sources, biological and environmental samples, and other unusual matrices. His expertise includes leaching studies, field studies, sampling, and analytical methodology used to determine mercury in geogenic, biological, and water samples.