Wastewater Workgroup

an icon of the outline of a pipe pouring liquid into a stream


To investigate sources of Per- and polyfluoroalkyl substances (PFAS) in wastewater that discharge to surface water (e.g., lakes, rivers, streams, etc.) or groundwater and implement source control through existing regulatory programs.

The Wastewater Workgroup includes staff from the Michigan Department of Environment, Great Lakes, and Energy (EGLE), Water Resources Division (WRD), Emerging Pollutants Section, Field Operations Section, Industrial Pretreatment Program (IPP), Point Source Monitoring Program, Permit Section, Surface Water Assessment Section, and Biosolids Program.

Recent Accomplishments:

  • A map of Michigan showing source tracking areas from the bulleted list under the heading 'Source Tracking'The Wastewater Workgroup has worked diligently to identify and control sources of PFAS, primarily perfluorooctanesulfonic acid (PFOS), being discharged to groundwater and surface waters of the State of Michigan.
    • Source Tracking: The Wastewater Workgroup conducted sampling of municipal and industrial discharges to rivers, lakes, streams, and groundwater as part of PFOS source tracking efforts.  These efforts led to identification and implementation of source control measures at permitted discharges that were determined to be significant sources in several watersheds.  These activities occurred/are occurring in the following areas:
    • Municipal Wastewater: The Wastewater Workgroup identified municipal Wastewater Treatment Plants (WWTPs) that receive wastewater from industrial facilities as a potential significant source of PFAS to surface waters.  As a result, the Wastewater Workgroup developed and implemented the IPP PFAS Initiative in 2018.  This initiative required 95 municipal WWTPs with IPPs to identify and control significant sources of PFOS to their system. To date, implementation of the Initiative has resulted in significant decreases of pollutants passing through WWTPs and entering the environment. Learn more about the IPP initiative.
      A person collecting a water sample from a pipe using a dipper.
      A person collecting a water sample from a pipe using a dipper.
    • Municipal NPDES Permitting Strategy: The Wastewater Workgroup developed a Municipal National Pollutant Discharge Elimination System (NPDES) permitting strategy for PFOS and perfluorooctanoic acid (PFOA).  The goal of the strategy is to continue to identify, reduce, and remove PFOS and PFOA at WWTPs.  See the Municipal NPDES Permitting Strategy for PFOS and PFOA for more information.
    • Point Source Monitoring: Since 2017, the Wastewater Workgroup has collected over 70 samples for PFAS analysis from permitted (and unpermitted) discharges from both municipal and industrial facilities.  Sampling occurs at permitted facilities in response to source tracking efforts or in response to specific concerns/knowledge about PFAS use at the facility.  In addition, PFAS analysis has been added to routine compliance sampling inspections for permitted facilities that have been determined to be a potential source of PFAS.  Moving forward, non-municipal wastewater NPDES dischargers that are found to be discharging PFOS and/or PFOA above water quality standards will be initially regulated through Administrative Consent Orders (ACOs) and then through NPDES permits as they are reissued.  The first such ACO became effective March 16, 2020.  These efforts, in combination with other effluent sampling conducted as part of a study by the Biosolids Workgroup, have helped narrow the focus on sources of PFAS to surface waters and understand the prevalence of PFAS (specifically, PFOS) in WWTP discharges. 
      Three EGLE staff with sampling equipment outside at a roadway manhole. A group of EGLE staff looking into a roadside manhole as part of an inspection
      The above images depict EGLE staff getting ready to and sampling a roadside manhole as part of an inspection.
    • Industrial Storm Water (ISW) Screening:  Industrial storm water regulations apply to a wide range of industrial and municipal facilities.  A phased approach to conduct screening at facilities regulated under the ISW program began in 2019.  This approach focuses on prioritized facilities with known use of PFAS containing products (mainly chrome platers and airports) and where elevated concentrations of PFOS in storm water are suspected due to known PFAS concentrations in groundwater, process industrial wastewater, soils, and/or surface waters associated with the facility. If initial sampling shows results over water quality values, then the facility will be required to take appropriate actions to reduce their discharge.
      Two people conducting an industrial storm water inspection; looking at an outdoor pumping system.
      Two people conducting an industrial storm water inspection; looking at an outdoor pumping system.
    • Industrial Direct Discharger and Industrial Storm Water Compliance Strategy: The Wastewater Workgroup developed a compliance strategy for addressing PFOS and PFOA discharges from industrial direct and industrial storm water discharges. The goal of the strategy is to reduce or eliminate PFOS and PFOA from industrial facilities holding NPDES and Groundwater Discharge permits to meet applicable criteria. See the Compliance Strategy for Addressing PFOS and PFOA from Industrial Direct and Industrial Storm Water Discharges for more information.

Next Steps:

As we move forward, more time will be devoted to both direct dischargers and permit development efforts, while the core IPP and point source monitoring efforts continue.  This workgroup will:

  • Continue implementation of IPP PFAS Initiative to identify and control sources in municipal WWTPs.
  • Assist WWTPs to institute pollution minimization/treatment strategies (PMPs) and sewer use ordinances (SUO) for PFOS and PFOA.  The SUO provides the legal authority for the PMPs.
  • Evaluate other NPDES permittees that were not included in the IPP PFAS Initiative to identify and control discharges of PFAS to surface waters and groundwater.  These include industrial direct dischargers and other WWTPs that do not have IPP requirements, as well as industrial storm water dischargers.
  • Incorporate monitoring in NPDES permits and ultimately (towards the end of the five‑year span) institute PFAS effluent limits for those that ultimately need to install treatment or other controls.
  • Coordinate closely with the Biosolids Workgroup on sampling conducted at WWTPs pursuant to the Statewide Biosolids Study.

Research/Studies and Reports: 

  • Michigan Chrome Plater Fume Suppressant Study:  The Wastewater Workgroup partnered with the United States Environmental Protection Agency (EPA), Office of Research and Development (ORD), National Exposure Research Laboratory to answer the question of whether current PFOS “replacement” products being used at chrome plating facilities were contributing to elevated PFOS in discharges from those facilities.  As part of this effort, EGLE sampled 11 chrome platers (effluent and fume suppressants) in July 2019.  The Wastewater Workgroup will share results to assist industry with decisions on product use, clean up, and treatment. Read the report, "Targeted and Nontargeted Analysis of PFAS in Fume Suppressant Products at Chrome Plating Facilities".
  • Municipal Wastewater and Biosolids/Sludge Study:  The Biosolids Workgroup contracted with a consulting firm, AECOM Technical Services, Inc. (AECOM), to conduct a study in the fall of 2018 of 42 municipal WWTPs to evaluate the presence of PFAS in influents, effluents, and associated residuals (sludge/biosolids) generated at the facilities.  As part of this initiative, screening of 22 land application sites was conducted to further understanding of the potential impacts to the environment from land-applied biosolids.  For this study, the WRD contracted with AECOM, to perform sampling at the WWTPs and land application field sites.  Samples were analyzed for 24 PFAS compounds.  Read a summary report that provides background and recent status updates of the IPP PFAS Initiative. A detailed report concerning this effort and the IPP PFAS Initiative is expected to be available by the summer of 2020. 
  • Identified Industrial Sources of PFOS to Municipal WWTPs (Report): The Wastewater Workgroup summarized the industrial sources of PFOS to municipal wastewater treatment plants (WWTPs) which were identified through the IPP PFAS Initiative. Sources are defined as those industrial users with discharges to WWTPs greater than 12 ppt, which was used a screening level. The majority of significant PFOS sources were metal finishers, contaminated sites associated with industries or activities with PFOS usage, and landfills that accepted industrial wastes containing PFOS. Read the report, “Industrial Sources of PFOS to Municipal Wastewater Treatment Plants as identified through the Michigan Department of Environment, Great Lakes, and Energy Industrial Pretreatment program Per-and Polyfluoroalkyl Substances Initiative”.

Research Needed:

There is still a lot of work to be done on all fronts to control and identify sources and identify treatment/reduction strategies for all types of wastewater, including leachate from landfills.  A better understanding of mass loading and potential breakdown of PFAS through various treatment processes at municipal WWTPs is important to aide municipalities and industries as they develop PFAS reduction strategies.

Timeline of Accomplishments: 

Wastewater Workgroup Lead Name and Email: 

Stephanie Kammer
Emerging Pollutants Section Manager, WRD

Webpage updated: August 25, 2020