First Illinois Groundwater Quality Standards for PFAS Chemicals Proposed

The Illinois Environmental Protection Agency (EPA) has filed administrated rules to create the first groundwater quality standards for PFAS chemicals in the state.


According to the IEPA in a recent announcement, it has submitted amendments to 35 Illinois Administrative Code (Ill. Admin. Code) Part 620 to the Illinois Pollution Control Board (Board).  The revised amendments update toxicity data for various chemicals, update exposure factors, and introduce groundwater quality standards for five Per- and Polyfluoroalkyl Substances (PFAS) chemicals.


New groundwater quality standards for five PFAS chemicals are to be included in the proposed rule:

  • Perfluorooctanoic Acid (PFOA);

  • Perfluorooctanesulfonic Acid (PFOS);

  • Perfluorononanoic Acid (PFNA);

  • Perfluorohexanesulfonic Acid (PFHxS); and

  • Perfluorobutanesulfonic Acid (PFBS)


Also, included in the proposed amendment are  groundwater quality standards for nine new chemicals, three new atrazine metabolites, and procedures for selecting toxicity values consistent with current federal guidance among other updates.


“This regulatory submittal is the culmination of work by Illinois EPA staff over the past two years in an effort to establish Illinois’ first groundwater standards for PFAS chemicals,” said IEPA Director John J. Kim in the release announcing the proposed rules. “These regulations are a significant step to regulating these forever chemicals that will allow Illinois to develop standards to more effectively protect the public and environment against adverse impacts associated with PFAS contamination.”


Merit Laboratories is a leading national PFAS environmental laboratory, analyzing drinking water, soil, wastewater, groundwater, and other sample matrices, including biosolids and sludge. Analytical methods performed by Merit for PFAS include drinking water by EPA 533, EPA 537.1, and EPA 537 rev. 1.1, biosolids by ASTM D7968-17 with Isotopic Dilution, and soil, wastewater, groundwater, and surface water by ASTM D7979-19 with Isotopic Dilution and ASTM D7968-17.