On December 7, 2021, the Illinois Environmental Protection Agency (IEPA) filed proposed amendments to Illinois’ groundwater quality standards with the Illinois Pollution Control Board (Board). The proposal includes Class I and Class II groundwater quality standards for six per- and polyfuoroalkyl substances (PFAS), including perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), perfluorononanoic acid (PFNA), perfluorohexanesulfonic acid (PFHxS), perfluorobutanesulfonic acid (PFBS), and hexafluoropropylene oxide dimer acid (HFPO-DA).  Illinois follows several states that are choosing to regulate PFAS constituents while federal regulation of the constituents is pending. Ubiquitous, PFAS can be found in a variety of consumer products, industrial processes, and fire-fighting foams, and can come to be located throughout the environment.

We previously provided an update on IEPA’s draft proposal for this rule. The current proposal, filed by IEPA with the Board, varies from that draft proposal in several significant ways. First, it adds a standard for the chemical HFPO-DA, sometimes referred to as “GenX,” which had not previously been included. Additionally, the proposed standards for the remaining PFAS constituents, which are set using a revised health-based risk formula, are more stringent than those in IEPA’s draft proposal. Finally, unlike the draft proposal, the filed proposal does not include a combined standard for PFOA and PFOS. The PFAS standards proposed to the Board are as follows:

PFBS 0.0012 mg/L
PFHxS 0.000077 mg/L
PFNA 0.000012 mg/L
PFOA 0.000002 mg/L
PFOS 0.0000077 mg/L
HFPO-DA 0.000012 mg/L

IEPA’s filing of this proposed rule with the Board initiates the official rulemaking process. As part of that process, interested parties will have the opportunity for public comment and participation prior to the promulgation of a final rule by the Board.

Photo of Bina Joshi Bina Joshi

Bina Joshi practices environmental law. Bina’s experience includes helping clients with all aspects of environmental litigation matters including issues arising under the Clean Air Act, CERCLA and related state laws. She regularly helps clients with compliance matters, both in dealing with compliance issues…

Bina Joshi practices environmental law. Bina’s experience includes helping clients with all aspects of environmental litigation matters including issues arising under the Clean Air Act, CERCLA and related state laws. She regularly helps clients with compliance matters, both in dealing with compliance issues as they arise, and helping to develop compliance programs and engage in future compliance planning. Her experience also includes representing clients in remediation matters under state and federal remediation programs. Additionally, Bina regularly helps clients respond to government requests for information, including under Section 114 of the Clean Air Act and Section 104(e) of CERCLA.