BROOKINGS (11-12-26) — At this week’s meeting, the Brookings City Council heard an update from Solventum concerning the ongoing mitigation of PFAS chemical contamination at their Brookings facility.
In 2022, a leak in the plant’s fire suppression water line resulted in water and soil contamination. A clean-up ensued, and Solventum continues to monitor for residual contamination.
David Stanesa is Senior Plant Director at the Brookings Solventum facility… “Through the course of 2025, there were 6 million gallons that were treated. We are on track for similar results this year, but up through September, we’re at 3.9 million gallons. This is the best practice, and (we) collaborated with the state on this, as far as the process to filter the water. It shows effective greater than 99.9 percent in removal since 2025 in April. The project was to address the surface water concentrations leaving the site, the southwest side of the plant.”
He said they plan ton continue mitigation efforts… “For the balance of ’26 and into ’27, we’ll continue with the stormwater treatment system at the facility that exits the southwest side of the plant. We’ll continue the testing as expected on-site and off-site wells. There is an upcoming discussion that we will be having with the state — I believe it’s in early next year, early to spring next year. They are asking for some additional locations of some well-monitoring sites that we will align on that and move forward on those.”
City Council Member Bonny Specker said she is still concerned about the concentration levels of PFAS detected… “The concentrations in September of 2025 was 300 nanograms per ml, where the EPA limit is 4 nanograms per ml. Granted, the EPA limit is for drinking water and this is surface water, so it’s conservative. But I think that it’s still important to realize that even though there’s been a lot of decrease, it’s still at fairly high amounts.”
Specker said she’s also concerned about the gradual flow of groundwater away from the Solventum property… “We don’t know — as far as well contamination — how long that might take to get to the wells that are used for irrigation of parks land. And I think it’s important to have a baseline prior to that flow reaching the current wells that you have that are at that southern end.”
Solventum is continuing to work with the state Department of Agriculture and Natural Resources on continued sampling, testing and treatment at the Brookings location.
BMU Water Quality
Specker, in her role as ex officio member of the Brookings Municipal Utilities Board, also updated the City Council on other water issues during this week’s meeting. She said BMU is working to expand the quantity and quality of water in the local area… “Six new municipal wells were installed in 2025 and 2026. In recent years, BMU has acquired critical property above the wellhead protection areas, and they’ve continued monitoring for groundwater flow rates and nitrate concentrations.”
She said BMU conducts a wide range of water tests… “This is a routine testing of many compounds with an increased focus recently on inorganic chemicals, nitrates, PFAS, and lead and copper testing. Nitrates can often be an issue in areas with high agricultural activity, but they are below the detection levels in source water at both well fields, in part due to purchasing land and changing the land use in the wellhead protection areas.”
Specker said BMU also tests for arsenic and PFAS contamination… “Arsenic is below the maximum containment levels, but has been an increased focus of testing based on national reporting of South Dakota as a state with localized elevated arsenic potential. PFAS have been undetectable in the Brookings water supply as well as the wellheads that are upstream from the 3M Solventum PFAS leak.”
The City of Brookings plans to continue coordinating with Solventum, the state Department of Agriculture and Natural Resources and BMU to monitor progress and support mitigation efforts at and around the Brookings Solventum site.
Solventum’s November 10 presentation to the Brookings City Council can be viewed at: https://cityofbrookings.legistar.com/View.ashx?M=F&ID=16127364&GUID=BD5F9294-C602-4A22-9100-4279DFEA0606
— Brookings Radio News
