IPP PFAS Initiative

The IPP PFAS Initiative required all municipal WWTPs with required IPPs (95 statewide) to find out if they were passing through PFOS and/or PFOA to surface waters and, if found, to reduce and eliminate any sources. Under the Initiative, WWTPs were required to:

Identify industrial users to their system that were potential sources of PFAS.
Sample probable sources and their WWTP discharge (effluent) if sources were above screening criteria (12 parts per trillion PFOS).
Require source reduction at confirmed sources. This is being accomplished through pollutant minimization plans, equipment/tank change out/clean outs, product replacement, and installation of pretreatment to remove PFAS, specifically PFOS, prior to discharge.
Monitor compliance of confirmed sources and ensure that they meet local IPP PFAS requirements.
Submit required reports and monitoring results as required by EGLE's Water Resources Division (WRD).

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As a part of this effort, the WRD developed numerous documents, including Frequently Asked Questions (FAQs), Wastewater PFAS Sampling Guidance, and Recommended PFAS Screening and Evaluation Guidance. These documents are linked below for your information.

Please see the Michigan PFAS Action Response Team page for Regulated Wastewater for additional PFAS information related to wastewater treatment plants.

Please see the Michigan Biosolids PFAS-related information and links page for more information specific to biosolids and updates to the Interim Strategy for Land Application of Biosolids Containing PFAS, which WRD began implementing in 2021.

Information about the IPP PFAS Initiative

Outreach to IPP WWTPs

EGLE sent a series of letters to IPP WWTPs in Michigan about the Initiative that describe its requirements and provide guidance:

9/10/2020 Update on IPP PFAS Initiative and Continued Efforts. Topics include IPP compliance, monitoring and enforcement responsibilities, PFOS/PFOA local limits development, WWTP effluent sampling and future NPDES limits, recently adopted MCLs, summaries of recent EGLE reports, and a biosolids program status update.
12/3/2019 Update on IPP PFAS Initiative Status and Continued Efforts. Topics include observations and progress by sources and WWTPs, a biosolids program status update, discussion of the NPDES municipal permitting strategy, and program updates.
4/18/2018 PFAS Source Evaluation Follow-Up Letter. Topics include regional meetings, additional guidance under development, clarification of expectations when sources are identified, and the landfill initiative.
2/20/2018 PFAS Source Evaluation and Reduction Requirements Letter. This is the initial letter establishing the IPP PFAS Initiative identifying required actions, reporting requirements, reduction goals, and providing guidance to POTWs implementing the initiative.

To kick off the effort, EGLE held IPP PFAS Initiative Regional Information Meetings in early 2018 and an EGLE IPP PFAS Initiative webinar (4/11/18, 61 min). EGLE developed general guidance to WWTPs based on the comments and questions received at these events. See Recommended PFAS Screening & Evaluation Procedure for IPPs and PFAS Frequently Asked Questions for IPPs. For guidance to WWTPs specific to sample collection and analysis, see Wastewater PFAS Sampling Guidance and Suggested PFAS Laboratory Analytes.

Strategy and Implementation

The strategy for the IPP PFAS Initiative may be understood by reviewing information in the "Outreach to IPP WWTP" section above. For information on Publicly Owned Treatment Works (POTWs) more commonly referred to as either municipal Wastewater Treatment Plants (WWTP), Wastewater Stabilization Lagoons (WWSL), or Water Resource Recovery Facilities (WRRF) that have tested for PFAS at their permitted discharge points or monitoring points, see the Michigan POTW with PFAS Data map.

The Municipal NPDES Permitting Strategy for PFAS describes how the IPP PFAS Initiative results affect NPDES permits for municipal wastewater treatment plants discharging to surface waters. Information about residuals management and PFAS may be found at the Michigan PFAS Action Response Team (MPART) Land Application Workgroup web page and the Michigan Biosolids PFAS-related Information and Links web page.

The United States Environmental Protection Agency (USEPA) issued a memo on December 6, 2022 providing recommendations to states to address PFAS in NPDES regulated discharges. The USEPA delegated Michigan the authority to administer the NPDES program in October of 1973. Starting in 2017, EGLE’s Water Resources Division (WRD) has developed compliance and permitting strategies to address PFAS discharges from NPDES permitted facilities in Michigan. EGLE WRD reviewed the USEPA memo and developed the following document comparing EGLE WRD’s compliance and permitting strategies with the USEPA’s guidance.

Addressing PFAS in NDPES Regulated Discharges: A Comparison of Michigan’s Compliance and Permitting Strategies and the USEPA Guidance

EGLE Research, Studies, and Reports

In addition to the IPP PFAS Initiative, EGLE has conducted a study of 42 municipal WWTPs to evaluate the presence of PFAS in influents, effluents, and associated residuals (sludge/biosolids), plus screening of 29 land application sites to further understand the potential impacts from land-applied biosolids. For a summary of the study and initial findings of the IPP PFAS Initiative, see the Summary Report: PFAS in Municipal Wastewater and Associated Residuals (Sludge/Biosolids). For the complete detailed report covering the IPP PFAS Initiative and the Statewide Study of 42 municipal WWTPs, see Evaluation of PFAS in Influent, Effluent, and Residuals of Wastewater Treatment Plants (WWTPs) in Michigan. For reports related to the screening of land application sites, see Michigan Biosolids PFAS-related Information and Links web page.

In fall 2021, EGLE completed a second statewide PFAS assessment of 44 WWTPs, which focused on resampling WWTPs included in the fall 2018 assessment as well as sampling WWTPs without IPPs and several with groundwater discharges. Influent, effluent, biosolids/sludge, and groundwater monitoring wells were sampled. This statewide sampling helps expand EGLE’s dataset and allows for evaluation of the effectiveness of industrial source control on reducing PFOS and PFOA at municipal WWTPs since the IPP PFAS Initiative was implemented in 2018. To read the report, see: Further Evaluation of Per-and Polyfluoroalkyl Substances (PFAS) from Wastewater Treatment Plant Influent, Effluent, and Residuals in Michigan (August 2025).

In 2025, EGLE is undertaking a third statewide PFAS assessment emphasizing non-IPP WWTPs with NPDES permits classified as USEPA minors. Sampling will include influent, effluent, and final solids for approximately 50 locations. Based on the results from the samples, further analysis may be performed at limited number of facilities for one or multiple analysis such as Total Oxidable Precursors Assay (TOP), Adsorbable Organic Fluorine (AOF) (only for influent and effluent), and Extractable Organofluoride Fluorine (EOF) (only for solids) to evaluate the presence and fate of PFAS precursors. This statewide study will improve Michigan’s dataset for non-IPP WWTPs and help inform future NPDES permitting decisions.

EGLE and the USEPA conducted the study, PFAS in Fume Suppressant Products at Chrome Plating Facilities, to assist in compliance efforts undertaken by the chrome plating industry in Michigan, where many platers have had to invest significant resources to install pretreatment systems to remove PFOS from their process wastewater even though they complied with federal requirements to discontinue use of the PFOS-based fume suppressants years prior. Samples of 9 different fume suppressants and effluent from 11 platers were collected in July 2019. See the above link for the full report and/or view the presentation slides about the study from the webinar and/or the presentation slides with speaker notes from the webinar.

EGLE review of data from the IPP PFAS Initiative found that the majority of significant PFOS sources to WWTPs were landfills that accepted industrial wastes containing PFOS, metal finishers with a history of fume suppressant use, and contaminated sites associated with industries or activities with PFOS usage. Other sources found included centralized waste treaters (CWT), paper manufacturing/packaging, commercial industrial laundries, chemical manufacturers, and sewers contaminated with aqueous film forming foam (AFFF). The report was originally published in August 2020 and has been updated in May 2025 to include additional and updated WWTP actions, significant PFOS sources, regulatory criteria, pretreatment and reduction efforts, and evaluations of the overall progress of the IPP PFAS Initiative. To read the report, see Identified Industrial Sources of PFOS to Municipal Wastewater Treatment Plants (Report).