On:
In: Drinking Water, Geogenic contaminants, groundwater, Matt Ginder-Vogel, Midwest Cambrian Ordovician Aquifer System, radium

Pumped from the vast layers of bedrock beneath our feet, groundwater is the source of drinking water for two-thirds of people living in Wisconsin. According to geochemist Matt Ginder-Vogel, what’s in that water is largely influenced by what’s in the rock.

A headshot of Matt Ginder-Vogel
Matt Ginder-Vogel is researching geogenic contaminants in public wells across Wisconsin. Photo credit: UW–Madison Department of Civil & Environmental Engineering

“Groundwater is not a lake underneath the ground. It’s water that’s in tiny pore spaces in the rock,” said Ginder-Vogel, an associate professor in the UW–Madison Department of Civil and Environmental Engineering. “So, it really interacts with the rocks around it.”

Under the right conditions, this interaction can cause naturally occurring or “geogenic” contaminants—like radium, arsenic, uranium and manganese—to leach from bedrock into groundwater.

Just where geogenic contamination is occurring in the state and how are the questions Ginder-Vogel and his team of graduate students are hoping to answer in new research funded by the University of Wisconsin Water Resources Institute.

Savannah Finley and Juliet Ramey-Lariviere are both graduate students working on the project. They’re digging through drinking water quality data from the Wisconsin Department of Natural Resources to identify municipal wells with high levels of contaminants. The goal is to provide a snapshot of geogenic contamination across the state so that folks know what’s in their water.

“We want to give a health progress report of our overall aquifer and say—here’s what we have. Here are the contaminants that we’re looking at,” said Finley.

 

A headshot of Juliet Ramey-Lariviere
Juliet Ramey-Lariviere. Submitted photo.
A headshot of Savannah Finley.
Savannah Finley. Submitted photo.

She and Ramey-Lariviere are working on a map that will show contaminant hotspots and the underlying bedrock in those locations to determine if there is a relationship between the two.

“The hope is, once we have this data, to lay it all out on top of one another and look at the different bedrock formations and hopefully try to tie in the bedrock formation with the different contaminants that we’re seeing,” said Finley.

The team is focused on public wells in the Midwestern Cambrian Ordovician Aquifer System, a horseshoe-shaped region that roughly occupies the southern two-thirds of Wisconsin. Once wells are identified, they’ll collect both water and rock samples and begin experiments in the lab, which will reveal the amount of contamination leaching from the samples and how fast it’s occurring.

“We’ll be taking rock sections and grinding them up and looking to see what comes off the rocks,” said Ginder-Vogel. “You expose them to water and see what partitions into the water. Then you can manipulate the conditions of water to release other contaminants.”

The team will then use these findings to create a model that identifies hotspots around the state prone to geogenic contamination. Ginder-Vogel hopes the model will raise awareness of the problem even if water utilities aren’t currently experiencing issues. Concentrations of naturally occurring contaminants can change over time. Take, for example, the city of Waukesha.

“[Waukesha] didn’t always have troubles with radium. But when they started pumping more groundwater—and the Chicago suburbs were also pumping more groundwater and were changing the flow path of the water—[Waukesha] started to have more and more trouble with radium,” said Ginder-Vogel.

A map of Wisconsin showing wells tested for radium and those that exceed drinking water standards. Wells that exceed standards are concentrated in the eastern half of the state.
A map of Wisconsin showing wells tested for radium and those with drinking water that exceeds the Maximum Contaminant Level (MCL) standard set by the EPA. Wells exceeding MCL are concentrated in eastern Wisconsin. Image credit: Savannah Finley and Juliet Ramey-Lariviere

“Once you’ve seen that, you can’t help but ask, is it happening with other things, other naturally occurring contaminants like arsenic?”

Ginder-Vogel said increased water use is what’s driving the changing concentrations. Pumping more water pulls groundwater through the aquifer in different ways and allows water to interact with bedrock it hadn’t before, picking up new contaminants.

“People who think about groundwater often think about it being this unchanging pool beneath the ground, but with all the water that we use and the way we move water around right now, there’s the possibility for lots of change,” he said.

Unfortunately for water utilities dealing with high levels of geogenic contaminants, the solution isn’t an easy or cheap one. Geogenic contaminants don’t biodegrade or go away. “They’re metals,” said Ginder-Vogel. “You can’t destroy them and remediate them. You can only move them from one place to another.”

One solution is to install treatment systems that remove contaminants from drinking water. It’s an expensive option, however, and small municipalities may not have the resources to support such an endeavor. Water utilities may also choose to rebuild a well in such a way that it avoids rock formations with high amounts of contaminants.

Ginder-Vogel’s hope is that the team’s research helps municipalities develop a plan before geogenic contamination becomes a problem. While they can’t change the bedrock, they can be strategic about how they pump water.

Said Ginder-Vogel, “We’re trying to be smart about our water resources.”

The post Groundwater on the rocks: WRI-funded research will map naturally occurring contaminants in public wells across Wisconsin first appeared on WRI.

Original Article

News Release | WRI

News Release | WRI

https://www.wri.wisc.edu/news/groundwater-on-the-rocks-wri-funded-research-will-map-naturally-occurring-contaminants-in-public-wells-across-wisconsin/

Jenna Mertz

On:
In: Matt Ginder-Vogel, Maureen Muldoon, Michael Cardiff, Research, Shangping Xu, Steve Loheide

The University of Wisconsin Water Resources Institute recently provided funds for three new projects that will conclude at the end of June 2025:

Risk From Pathogens and Exposure to Antibiotic Resistance Genes in Private Wells in Southwest Wisconsin, led by Maureen Muldoon at the University of Wisconsin-Madison

Here’s things that are true about the southwestern Wisconsin counties of Lafayette, Grant and Iowa: they are predominantly rural, people living there mostly get their drinking water from private wells and the water sources lie under fractured rock, which means septic systems and agricultural practices can more easily contaminate the water supply. This research team has recent findings of viral, bacterial and protozoan pathogens in 66 of the 138 private wells in the area, but the health risk associated with this contamination is unknown. That’s in keeping with the broader lack of knowledge about the health risk associated with private well water. This project has three objectives 1) quantify the health risk associated with 10 pathogens detected in wells 2) evaluate well construction and geologic factors for pathogen contamination and 3) assess antibiotic resistance genes co-occurrence with human and livestock fecal contamination.

An Experimental Investigation on the Leaching of Per- and Polyfluoroalkyl Substances (PFAS) From Contaminated Soil, led by Shangping Xu at the University of Wisconsin-Milwaukee

The majority of people in Wisconsin get their drinking water from groundwater. This project will attempt to build an understanding of how what are known as “forever chemicals,” per- and polyfluoroalkyl substances (PFAS), might move through soil and into groundwater drinking water sources. The research team will collect soil core samples from several Wisconsin location, including samples based on factors like soil type, properties and PFAS contamination history. They will apply collected rainwater to the soil cores at rates simulating natural conditions. The rainwater flow patterns will be monitored, and leachate will be collected to measure its volume and its PFAS concentrations. If different transport behavior of PFAS within soil cores collected from different sites is observed, the comparison of the soil physicochemical properties and hydrological patterns will provide clues to the key factors that control PFAS mobility within the vadose zone (where the land and the aquifer meet). This work may also yield knowledge of “high risk” and currently overlooked PFAS areas.

Long-Term Threat of Geogenic Contaminants to Water Quality and Quantity in the Midwestern Cambrian Ordovician Aquifer System, led by Matt Ginder-Vogel at the University of Wisconsin-Madison

The Cambrian Ordovician Aquifer System underlies most of Wisconsin. It’s a system with naturally occurring contaminants—uranium, radium, arsenic and manganese. This project seeks to understand the sources and temporal trends of these contaminants because their variations complicate municipal water system management. The research team will identify six study sites, obtain well cuttings and/or core materials from the sites, quantify the presence and prevalence of potential contaminants and then construct models of how the contaminants move in the system. This will help water managers build and manage wells in a way that prevents water users from being exposed to contaminants.

Green field with water in the background.
Wisconsin is rich with surface water. Its groundwater assets are also critical to the economy and people’s health. New groundwater research will serve the state.

Two University of Wisconsin-Madison-based projects kicked off last July and are ongoing with completion targeted for next year:

Aligning the Wisconsin Idea on Water: Interpreting Public Perspectives and Values, led by Michael Cardiff

This project is documenting rural perspectives (attitudes, perception and values) related to groundwater issues, and the variability of these perspectives within the state through “Wisconsin’s Waters Survey”—a community-sourced public survey to be delivered to a range of rural communities. Rural land covers most of the state, overlies the majority of groundwater and the range of issues that may be important to the rural public is vast, from quality concerns such as nitrate and microbial contamination, to quantity concerns that include agricultural irrigation needs and impacts of groundwater to springs and streamflows.

Biomanipulation of Groundwater Flooding, led by Steve Loheide

This project is examining the causes of groundwater flooding, which leads to the loss of farmland and permanent inundation of homes. Such flooding can happen when extremely flat, internally or poorly drained landscapes get hit with a quantity of rain that doesn’t otherwise drain away, infiltrate the soil without flooding or dissipate through the atmosphere. The research team is examining Dane and Columbia counties’ flood records from the 1930s to the present to identify flood causes and how such factors may have changed through time.

 

 

 

 

The post Water Research Projects Announced first appeared on WRI.

Original Article

News Release | WRI

News Release | WRI

https://www.wri.wisc.edu/news/water-research-projects-announced/

Moira Harrington

On:
In: Amy Plechacek, Cambrian-Ordovician Aquifer System, Fond du Lac, Lake Winnebago, Matt Ginder-Vogel, radium, Ripon, sample, Sean Scott, strontium, Wisconsin State Laboratory of Hygiene
Photo credit: Michael Tavrionov, Pixabay

You take a seat at the table for a meal in Fond du Lac, Wisconsin, and may have a glass of water to accompany the entrée.

If you are University of Wisconsin-Madison Civil and Environmental Engineering Professor Matt Ginder-Vogel and graduate student Amy Plechacek, each with your tumbler full of water, you are turning to a different kind of table than a dinner table. You are at the periodic table of elements. You want to understand what’s in your glass; how the interactions between water and rock in Fond du Lac County might result in naturally occurring contamination of public drinking water wells and nearby private wells.

As part of a currently funded project through the University of Wisconsin Water Resources Institute, the pair has looked at municipal and well drinking water pumped from the Cambrian-Ordovician Aquifer System underlying parts of the Midwest, including this region of Wisconsin. In some locations it contains elevated Ra and Sr and can be affected by salinity, due to high concentrations of ions such as Ca, CI and SO42-.

For those us of who just want to tuck into that dinner in Fond du Lac and not strain to recall what’s on the periodic table, those initials stand for radium (Ra) and strontium (Sr). The Ca is calcium, CI is chloride and SO42- is sulfate.

Radium is regulated in drinking water by the U.S. Environmental Protection Agency (EPA) because long-term ingestion is associated with development of bone cancer. Strontium is on the U.S. EPA Contaminant Candidate List 3 and may be regulated in the future. Known health effects of elevated strontium consumption include tooth mottling and “strontium rickets,” a musculoskeletal disease.

“There’s a general background concentration of radium, then, depending on specific and unique factors at individual sites, you can end up above the maximum contaminant level for radium,” Ginder-Vogel said. Photo credit: UW-Madison College of Engineering, Dept. of Civil Environmental Engineering

Why Fond du Lac? Ginder-Vogel explained, “They have really interestinggeology in their aquifer. The very bottom surface of the aquifer is really uneven and parts of it are very deep where people get water, while other parts are much more shallow where they get water, so there’s just a lot of interesting natural variability.”

He continued, “It’s kind of perfect. It’s like someone set up an experiment for us already. We have all these variations in where the water comes from out of the aquifer and the environments where the water is coming from. So it lets us start to get a handle on all the factors that control naturally occurring contaminants in the water.”

Ginder-Vogel said he’s conducted radium-groundwater research for six years and has come to the realization that there’s often a small amount of radium in most of the Cambrian-Ordovician Aquifer System. “There’s a general background concentration of radium, then, depending on specific and unique factors at individual sites, you can end up above the maximum contaminant level for radium,” he said. “When we, Madeline Gotkowitz (formerly with the Wisconsin Geological and Natural History Survey) and I, got started on this we expected there to be an answer for Wisconsin at least. But really, what we’re discovering, is that it’s an incredibly variable system and really dependent on both well construction and also local structures in the aquifer systems.”

So, understanding one system—Fond du Lac’s—could inform other managers about water conditions and recommendations for where to drill in their own parts of the Badger State based on that comparison and contrast with this county near Lake Winnebago.

When Plechacek joined the effort to understand how the radium and strontium levels change with the geology in Fond du Lac, she also brought another critically important thing—a skill at engaging community members.

Researcher Amy Plechacek said the study was exciting because it identified one county’s zones of water chemistry. Contributed photo.

Plechacek composed a water-sampling request letter and distributed it to 40 or so well-owners, eliciting a positive response from about half of the people. Those who agreed were private homeowners or folks managing places like parks, gas stations or hotels.

She termed it an “awesome” experience that enabled her “look at some shallower wells as of a contrasting type of groundwater to these deep municipal wells.” The municipal well samples were collected through collaboration with the Ripon and Fond du Lac water utilities.

Plus, local enthusiasm for the project continued to run high. Even after she had completed her sampling rounds, Plechacek kept hearing from those with the shallower wells who wanted to volunteer to help.

Through an analysis of the samples—pioneered by Sean Scott, assistant scientist at the Wisconsin State Laboratory of Hygiene and a person who Ginder-Vogel described as “incredibly critical” to the project—the team could get quite precise results from the different locations. Scott’s method uses smaller-quantity water samples, allowing for less variability in results, providing a clearer picture of groundwater flow and geochemical conditions at the site.

The team ended up characterizing, Plechacek said, “Three distinct water chemistries. That’s one of the things that water utilities have to consider, the pros and cons of using shallow versus deep groundwater. There’s some contaminants that are likelier to be in shallower water, like nitrate is a big issue. But then with the deeper waters you tend to have more problems with things like radium. There’s a lot of tradeoffs. But I think the study was exciting because it identified the zones of water chemistry in that area.”

Water managers and private owners now have plenty of food for thought. The research will help determine how best to site wells to put the best possible glass of water on Fond du Lac tables, and will offer insights on how to minimize these contaminants in drinking water throughout the state.

 

The post Radium and strontium researchers take a seat at the table first appeared on WRI.

Original Article

News Release | WRI

News Release | WRI

https://www.wri.wisc.edu/news/radium-and-strontium-researchers-take-a-seat-at-the-table/

Moira Harrington

On:
In: Eric Stewart, James Price, Jim Hurley, Kevin Masarik, Matt Ginder-Vogel, Sarah Vitale

Four new projects focused on Wisconsin groundwater are underway on university campuses, as of July 1, as well as a continuing one. The work is funded by the University of Wisconsin Water Resources Institute (WRI).

“We look forward to the findings from this latest group of projects that address emerging issues,” said Jim Hurley, WRI director. “Each project advances our understanding of Wisconsin’s buried treasure, our groundwater.”

The projects will:

-Investigate in-season cover crops for reducing nitrate loss to groundwater below potatoes. Kevin Masarik at the University of Wisconsin-Stevens Point will lead the project. His colleague Jacob Prater on that campus will also participate in the exploration that will inter-seed the crops and assess the positive and/or negative interactions on potato yield, quality and ease of harvest.

Wisconsin is a major national potato producer and a WRI researcher will look at nutrients and groundwater needed for that cultivation. Photo by UW-Madison.

-Formulate a cost-function analysis of Wisconsin water utilities to place a value on groundwater. James Price is this investigator, based at the School of Freshwater Sciences, UW-Milwaukee.

-Conduct further research on the issue of arsenic in southeastern Wisconsin groundwater. Eric Stewart, bedrock geologist at UW-Madison, will correlate bedrock fold and fractures with the detection of this naturally occurring but carcinogenic chemical in drinking water.

-Provide insight into the sources of salinity associated with radium and strontium in the parts of the aquifer underlying eastern and northeastern Wisconsin. The study will provide an understanding of the movement of these contaminants to municipal wells. UW-Madison’s Matt Ginder-Vogel is the principal investigator and he has pulled onto the team Patrick Gorski and Sean Scott, both with the Wisconsin State Laboratory of Hygiene.

-As part of a project that kicked off in 2019, Sarah Vitale, and co-investigator J. Brian Mahoney at UW-Eau Claire and Anna Baker with the U.S. Geological Survey Upper Midwest Water Science Center, are investigating naturally occurring phosphorus in western Wisconsin surface and ground waters.

The post University-based research projects to examine Wisconsin’s “buried treasure:” Groundwater first appeared on WRI.

Original Article

News Release – WRI

News Release – WRI

https://www.wri.wisc.edu/news/university-based-research-projects-to-examine-wisconsins-buried-treasure-groundwater/

Moira Harrington