Andrew H. Manning is a Research Geologist with the U.S. Geological Survey in Denver, Colorado. He has over 20 years of experience as a hydrogeologist and geochemist, working in both research and consulting. He received an M.S. in structural geology in 1993 and a Ph.D. in hydrogeology in 2002, both from the University of Utah. He joined the USGS in 2003 and has since worked on a broad spectrum of projects related to regional groundwater flow, groundwater flow in mountainous terrain and fractured rocks, groundwater age dating, and the role of groundwater in the formation of mineral deposits.