Skip to main content

Michigan limits on PFAS in public drinking water supplies added to groundwater clean up rules

Low-flow groundwater sampling for PFASMichigan's limits on per- and polyfluoroalkyl substances PFAS in public drinking water supplies have officially been added to the state's groundwater clean-up rules.

In effect and enforceable since December of 2020, limits on seven PFAS compounds were officially added to the 2020-130 EQ "Cleanup Criteria Requirements for Response Activity" rule set on Feb. 15, 2022. The purpose of this rule set is to add the previously established PFAS in drinking water limits as a new table under Rule 44, which contains the generic cleanup criteria for groundwater.

The updated groundwater rule builds on rules promulgated by EGLE and approved by the Environmental Rules Review Committee in 2020 that established PFAS standards for safe water at public water supplies. The residential and nonresidential drinking water generic cleanup criteria, and Groundwater Surface Water Interface Criteria are as follows:

PFAS Hazardous Substance

CAS Registry Number

Generic Cleanup Criteria

Groundwater Surface Water Interface Criteria



Hexafluoropropylene oxide dimer acid (HFPO-DA)




Perfluorobutane sulfonic acid (PFBS)




Perfluorohexane sulfonic acid (PFHxS)




Perfluorohexanoic acid (PFHxA)




Perfluorononanoic acid (PFNA)




Perfluorooctanoic acid (PFOA)




Perfluorooctane sulfonic acid (PFOS)




EGLE's Remediation and Redevelopment Division followed the process prescribed in Part 201 to develop values for the generic groundwater criteria for the drinking water pathway for the seven PFAS compounds. Although the groundwater values differed from the State Drinking Water Standards that were promulgated in August 2020, state regulations dictate that the criteria must correspond with state drinking water standards.

This creates regulatory certainty for individuals that cause or are impacted by PFAS contamination in groundwater used for drinking water, because Michigan uses the generic cleanup criteria to determine "facility" status. Determining facility status is the threshold for all responsibilities and requirements of the cleanup program.

Michigan's generic cleanup criteria also provides a party responsible for addressing a contaminant with the appropriate tools to determine if response activities or other actions should be taken at a contaminated site to prevent unacceptable exposure to the public. A responsible party can use these generic cleanup criteria as their cleanup levels to achieve "no further action." A responsible party can also use site-specific criteria based on a site-specific risk assessment, approved by the department, in lieu of the generic cleanup criteria.

In summary, this new rule adopts the state drinking water standards as the Part 201 generic groundwater criteria for the drinking water pathway, consistent with state law, ensuring that the drinking water of all Michiganders -- whether from a public water supply or for a private well -- are equally protected.

Currently, nearly 3 million Michiganders obtain their drinking water from a private well.

Caption: Low-flow groundwater sampling for PFAS.

Like this content? Follow us on TwitterFacebookLinkedIn, and on YouTube.

Take a short survey and let us know what you think about MI Environment.