Jim Hurley is a busy man. In addition to conducting research as a professor of civil and environmental engineering at the University of Wisconsin-Madison, Hurley chairs the interdisciplinary Environmental Chemistry and Technology (EC&T) graduate program and directs two federal-state research partnership programs for the UW System—the Wisconsin Water Resources Institute and Wisconsin Sea Grant, which are administered by the U.S. Geological Survey and NOAA’s Office of Oceans and Atmospheric Research, respectively.
“It’s a perfect position as far as I’m concerned,” says Hurley of his interrelated roles on campus. “I get to be not only a part of cutting-edge research, but I get to run statewide programs that people are just passionate about.”
The passion for these programs and what they represent—clean water, thriving coastal communities, innovative problem solving—runs deep among both the stakeholders the programs serve and the scientists whose research they fund. A lot of that important research is done by Hurley’s colleagues in the Department of Civil and Environmental Engineering (CEE).
For instance, Wisconsin Sea Grant has funded research by CEE Professor Chin Wu that is addressing Lake Michigan’s coastal bluff erosion. It’s an urgent problem for many of Wisconsin’s coastal communities.
“Three years ago we were near record lows on Lake Michigan, and in the three years since the lake came up almost four feet and is now close to record highs,” Hurley says. “That puts tremendous stress on coastal bluffs and shores. It’s important that we understand it and work with people who own property near the bluffs to suggest ways they should respond to it.”
Other CEE faculty with research funded by Wisconsin Sea Grant include Steve Loheide, who is researching green infrastructure that can mitigate the damage of large storms on Wisconsin’s harbors and coastal infrastructure; Christy Remucal, who is studying photodegradation of pharmaceuticals and certain pesticides in Wisconsin surface waters; and Matt Ginder-Vogel, who is working with researchers from Minnesota on mercury dynamics.
Hurley himself studies mercury in the Great Lakes as part of his faculty research role, and some of his latest research funded by EPA has uses far beyond the Great Lakes. Together with EC&T graduate student Ryan Lepak, Hurley has developed a method that can tell the general origin of mercury contamination based on its isotopic ratios. Understanding the local sources of mercury contamination can help resource managers develop better mitigation practices.
Generally, mercury that accumulates in lakes originates from one of three sources: the atmosphere, by way of precipitation; on- or near-shore industrial discharge; or via rivers that drain surrounding watersheds into the lakes. With the knowledge that the isotopic fingerprint of mercury found in Great Lakes sediments varies by location, Hurley and Lepak proposed a model that accounts for the three major sources of mercury. The three-end-member mixing model predicted that the site-specific contribution of these three sources to the Great Lake sediment result in mercury deposition with distinct isotopic fingerprints.
Lepak and Hurley analyzed sediment samples taken by the USGS from sites all over the five Great Lakes. Their results confirmed their three-end-member mixing model, and thus provide a new tool for environmental resource and mitigation experts in their efforts to reduce mercury contamination in the Great Lakes and beyond. They show for instance, that most mercury in sediments of Lake Superior arrived by atmospheric deposition while mercury in sediments of Lake Ontario are mainly from industrial contamination.
The isotopic research is also beginning to shed light on which mercury contamination sources might pose greater food consumption risks. Hurley says that it appears that methylmercury—the organic form of mercury that accumulates in fish through the food web—is associated with atmospheric mercury. For some reason, preliminary results suggest that atmospheric mercury sources are more susceptible to methylation by microbes, Hurley says, making it much more likely to accumulate in the food web. The largest source of atmospheric mercury worldwide is from coal-fired power plants.
The mercury isotope research represents the value multidisciplinary research, common to water-related issues studied by Wisconsin Sea Grant, the Water Resources Institute and CEE, Hurley says. “Wisconsin Sea Grant responds to the needs of our coastal constituents,” Hurley says. These needs are complex and typically require expertise and research grounded in biology, chemistry, engineering, the social sciences and many other disciplines, he adds.
“We’re about identifying coastal problems and finding the best Wisconsin researchers to help solve those problems, and get those results to our stakeholders. That’s the trust that we’ve built,” Hurley says. “We do it as neutral brokers. We bring coastal science to the table do it with a non-advocacy approach.”
Author: Will Cushman