« All Events

  • This event has passed.

Colloquia – Athena Nghiem

December 4 @ 4:00 pm – 5:00 pm

A tale of two redox-sensitive trace elements: from Southeast Asia to Southeast Wisconsin

Athena Nghiem explores environmental variability in hydrology and redox processes affecting critical water resources such as groundwater, and the drivers for the release, fate, and transport of trace elements and contaminants across different reservoirs in the environment. My research focuses on combining traditional laboratory and field approaches with data science and process-based modeling, incorporating a variety of techniques that range from X-ray absorption spectroscopy to reactive transport modeling. My aim is to quantify hydrological and biogeochemical cycling impacts on groundwater and other water resources under local to global scenarios of change and to address community-motivated questions related to the sustainability of water resources.

Athena Nghiem, Assistant Professor
Department of Geoscience
University of Wisconsin-Madison

Trace elements are naturally occurring in low concentrations in the environment. However, some trace elements can have a disproportionate impact on human health due to their presence in groundwater. For example, consumption of groundwater naturally contaminated with the toxic trace element arsenic (As) in groundwater affects millions of people worldwide, especially in South and Southeast Asia. Meanwhile, molybdenum (Mo) has been investigated to a much lesser extent and is essential at low concentrations, but toxic at high concentrations – a local hotspot of which has been previously found in Southeast Wisconsin. Importantly, the mobility in the subsurface of many trace elements, including As and Mo, are governed by redox-sensitive solid-solution partitioning. Understanding speciation of these trace elements, both in the solid-phase and in the aqueous phase, is critical to understanding their mobility in groundwater. Using techniques ranging from traditional lab and field measurements to synchrotron spectroscopy, in this talk, I will present research highlights from our new investigations of trace element mobilization in case studies spanning from Southeast Asia to Southeast Wisconsin.

Julie Bowles

Lapham Hall Room N101

3209 North Maryland Avenue
Milwaukee, Wisconsin 53211 United States + Google Map