When
Monday, March 2, 2026, at 10:00 a.m.
Raina M. Maier
Professor
Environmental Microbiology
University of Arizona
"Mining in a Greener Future"
Harshbarger 118A-A1
ABSTRACT: Residual mine waste is among the largest waste streams globally. These materials exhibit wide variability in pH and metal contamination but commonly lack the soil structure and nutrients needed to support plant growth. As a result, mine wastes are highly susceptible to wind and water erosion, leading to human and ecosystem exposure to airborne particulates and to metal contamination of surface and groundwater.
As part of the University of Arizona NIEHS Superfund Research Program, we are investigating strategies to reclaim mine wastes. One promising approach is revegetation, in which plants can be used to either stabilize metals in situ or promote their uptake into above-ground tissues, depending on species, site conditions and community priorities. I will present research on plant surveys used to identify candidate species, as well as on root–microbe–metal interactions that can be harnessed to enhance revegetation, drawing on results from a seven-year field study at the Iron King Mine and Humboldt Smelter Superfund site. This site typifies legacy mine wastes characterized by low pH and high metal content.
Finally, I will place this work in the broader context of University-wide efforts to build national leadership in sustainable mining, critical minerals research and workforce development.
BIOSKETCH: Raina Maier is a professor of environmental microbiology at the University of Arizona whose research explores how microbes and their activities and products can be harnessed to protect human health and remediate contaminated environments. She is widely recognized for pioneering work on microbially produced surfactants—molecules that have led to new approaches and patents in environmental cleanup and metal recovery, particularly in mining-impacted systems. Her group also studies how microbial diversity shapes ecosystem function in arid landscapes, including mine tailings and desert soils, and has helped redefine how revegetation of mine waste is evaluated. She has served as director or associate director of the UA NIEHS Superfund Research Center since 2002 and co-founded the Center for Environmentally Sustainable Mining.