In 2007, not long before the Minnesota Pollution Control Agency was to approve a new NPDES permit for Brainerd Public Utilities’ wastewater-treatment-facility upgrade, an agency study detected PFOS (perfluorooctane sulfonate, a type of PFAS) in BPU’s wastewater effluent at significantly higher concentrations than were found in the effluent of other municipalities tested.
To keep NPDES permit approval on track, MPCA staff recommended that BPU find the source. Because a pending low-interest loan for facility upgrades was tied to permit issuance, the utility had to act fast. Barr was hired to help find the source of PFOS entering BPU’s sewer system. Within 10 days, we had collected water samples, coordinated laboratory analysis, and determined the primary source: an automotive-chrome refinishing facility.
We then met with the MPCA, BPU, and city staff to discuss probable NPDES-permit effluent limits for the reach of the Mississippi River to which BPU’s facility discharges. With Barr’s negotiating assistance, BPU was able to establish limits for PFOS that both met the agency’s stringent standards and were achievable for the utility.
After the permit was issued, Barr worked closely with BPU’s legal counsel to preclude a lawsuit from an environmental group.