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Investigations and Sites

Drill rig drilling a drinking water well.

Investigations and Sites

The State of Michigan is working proactively to identify locations where PFAS may be present as a contaminant. The Michigan Department of Environment, Great Lakes, and Energy (EGLE) is conducting testing in drinking water, groundwater, lakes & streams, soils, sediments, wastewater, and the PFAS foam that can accumulate at lakes and rivers. EGLE is also partnering with the Michigan Department of Health and Human Services (MDHHS), and the Michigan Department of Natural Resources (MDNR) to test fish and wildlife; MDHHS works with local health departments to issue any necessary health advisories. The state of Michigan is committed to sharing information with residents regarding PFAS testing that is occurring throughout the state.

Site investigations get started for a variety of reasons.  At some sites, like Superfund sites, Michigan Department of Environment, Great Lakes, and Energy (EGLE) staff have been overseeing environmental cleanup efforts for many years, and may add PFAS sampling to ongoing sampling if PFAS was known or suspected to have been used at the site. EGLE staff also conduct routine monitoring of rivers and lakes. If a sample exceeds water quality standards, staff work upstream until they find the site contributing to the PFAS. Other sites were sampled due to historical information, such as Carl's Retreading, which was where tires burned for many days and firefighting foam containing PFAS was used. PFAS investigations are also being conducted by responsible parties under various programs overseen by EGLE.   

On August 3, 2020, the groundwater cleanup criteria became PFOA of 8 ppt and PFOS of 16 ppt.  On December 21, 2020, five additional PFAS compounds became effective and enforceable groundwater cleanup criteria: PFNA (6 ppt), PFHxS (51 ppt), PFHxA (400,000 ppt), PFBS (420 ppt), and HFPO-DA (370 ppt).  EGLE staff use all 7 PFAS criteria to guide groundwater investigations, protect public health, and identify MPART PFAS sites.

Evolution of Groundwater Cleanup Criteria for PFAS

Compound Prior to August 3, 2020 Effective August 3, 2020 Effective December 21, 2020
PFOA 70 ppt (combined with PFOS) 8 ppt 8 ppt
PFOS 70 PPT (combined with PFOA)  16 ppt 16 ppt
PFNA N/A N/A 6 ppt
PFHxS N/A N/A 51 ppt
HFPO-DA N/A N/A 370 ppt
PFBS N/A N/A 420 ppt
PFHxA N/A N/A 400,000 ppt
  • The following explains how the PFAS Investigations page has transitioned over time, how the Michigan Department of Environment, Great Lakes, and Energy (EGLE) investigations get started and what constitutes a PFAS site.

    On November 13, 2017, the Michigan PFAS Action Response Team (MPART) originally listed 28 investigations which included areas of groundwater contamination as well as rivers and public water supplies.  MPARTs definition of a “site” changed in 2018 such that a site was where one or more groundwater monitoring result exceeds groundwater clean-up criteria.  In August 2018 Gilkey Creek and the Clinton River were no longer classified as a “site” and so were moved to the Watershed Investigations page.  Five public water supply locations previously listed as “sites” were moved to a Drinking Water page. Since that time the PFAS Sites page features groundwater investigations being conducted around the state with a result that exceeds groundwater clean-up criteria.

    In 2018, EGLE's Remediation and Redevelopment Division established cleanup criteria for groundwater used as drinking water of 70 ppt of PFOS and PFOA, individually or combined.

    On August 3, 2020, the groundwater cleanup criteria became 8 ppt PFOA and 16 ppt PFOS.  On December 21, 2020, the following 5 additional PFAS compounds became groundwater cleanup criteria: PFNA (6 ppt), PFHxS (51 ppt), PFHxA (400,000 ppt), PFBS (420 ppt), and HFPO-DA (370 ppt).  EGLE staff use all 7 PFAS criteria to guide groundwater investigations, protect public health, and identify MPART PFAS sites.