Researchers from the University of Minnesota and Brown University have field-validated an injected ultra-fine activated carbon technique that captures PFAS from contaminated groundwater. Funded by the U.S. Department of Defense and published in The Journal of Hazardous Materials, tests showed the approach can lower PFAS concentrations and, in some cases, reduce levels to below detection limits. The method adsorbs PFAS rather than destroying them, but it may offer a lower-cost, simpler option for protecting drinking water while further work investigates long-term management.
Field-Validated Cleanup: Injected Ultra-Fine Carbon Captures PFAS From Groundwater
Researchers from the University of Minnesota, working with engineers at Brown University, have taken a laboratory technique into the field and demonstrated a promising new way to capture per- and polyfluoroalkyl substances (PFAS) from contaminated groundwater.
Field Validation of an Injected Carbon 'Filter'
The team, led by Matt Simcik, PhD, of the University of Minnesota School of Public Health, published their field results in The Journal of Hazardous Materials. The effort began with funding from the U.S. Department of Defense to develop a practical approach for capturing PFAS that persist in soil and groundwater after use in consumer products, industrial applications and firefighting foams.
How the Method Works
The technique injects an ultra-fine activated carbon material into the subsurface to form a permeable treatment zone around a well. Groundwater is pushed through this carbon zone and then recovered; PFAS compounds adsorb onto the carbon much like particles caught in a filter.
"We drilled a well, and we pushed our material out around the well, sort of creating like a filter, like a Brita filter if you will. And suck the water back in, and it captured all of the PFAS. So, it was nice to see that what we had done in the lab was actually what we saw in the field as well," said Simcik.
Key Findings and Limitations
The field tests showed the injected carbon can capture significant quantities of PFAS and, in some cases, reduce concentrations to below detection limits. The researchers emphasize an important limitation: this approach adsorbs and captures PFAS but does not chemically destroy or degrade the compounds. That distinction affects long-term management and disposal of PFAS-laden materials.
Advantages reported by the team include potentially lower cost and simpler deployment compared with some conventional treatment systems, since the in-situ approach can require less equipment and shorter installation time.
Implications and Next Steps
By demonstrating viability in a real-world setting, the study represents an important step toward practical remediation tools that can protect drinking water supplies and reduce long-term exposure to so-called "forever chemicals." Further research will be needed to assess long-term performance, carbon regeneration or disposal strategies, and how the method performs across varied hydrogeologic conditions and PFAS mixtures.
Source: Results reported in The Journal of Hazardous Materials; field reporting by FOX 9 and University of Minnesota press materials.
