The most widespread contaminant of groundwater is not a microbe, industrial chemical or harmful element such as arsenic, according to University of Delaware geologist Holly Michael. It's seawater.

"Salt is everywhere along the coast," Michael said. "With sea-level rise, groundwater salinization could become more of an issue."

The assistant professor of geological sciences in UD's College of Earth, Ocean, and Environment (CEOE) is studying how seawater along the coast mixes with freshwater that flows underground, and she recently received a highly competitive Faculty Early Career Development Award from the National Science Foundation (NSF) to further her work.