PFAS above EPA’s limits in Illinois.

13 utilities of the 477 EPA tested in Illinois had a sampling location whose PFAS average was above a 2024 limit in its final UCMR 5 data, by EPA’s own method.

The short answer

13 utilities serving 353,817 people, as they report it, had a location averaging above a limit, most often PFOA (9) and PFOS (7). The largest is IL American - Peoria, whose highest PFOS average was 4.1 ppt, 1.02 times the limit. The furthest above is Crest Hill, at 3.1 times the PFOA limit.

These are EPA’s survey results, not violations: the limits take effect April 26, 2029, and compliance will rest on each utility’s own monitoring. EPA has proposed changes to the rule; as of Oct. 13, 2026, none is final.

Utilities above a limit

Largest first. Each one’s highest location average is for the limit it is furthest above, with the single highest sample of the same PFAS; its report has every result.

Illinois utilities above a 2024 PFAS limit
Utility	Based in	Serves	Above	Highest location average	Highest single sample
IL American - Peoria	Peoria	137,575	PFOS	PFOS 4.1 ppt1.02 times the limit	6.5 ppt
North Park PWD	Machesney Park	35,580	PFOA, PFOS, PFHxS, Hazard Index	Hazard Index 1.621.6 times the limit	—
Galesburg	Galesburg	31,620	PFOA	PFOA 11 ppt2.8 times the limit	14 ppt
Collinsville	Collinsville	30,616	PFOA, PFOS	PFOA 9.0 ppt2.3 times the limit	18 ppt
Freeport	Freeport	23,930	PFOS	PFOS 11 ppt2.7 times the limit	14 ppt
South Elgin	South Elgin	23,648	PFOA	PFOA 5.4 ppt1.4 times the limit	5.7 ppt
Crest Hill	Crest Hill	20,223	PFOA	PFOA 12 ppt3.1 times the limit	14 ppt
IL American - Lincoln	Lincoln	15,200	PFOA	PFOA 5.5 ppt1.4 times the limit	5.7 ppt
Channahon	Channahon	13,380	PFOS	PFOS 5.7 ppt1.4 times the limit	5.9 ppt
IL American - Whispering Hills	Godfrey	8,300	PFOA	PFOA 4.2 ppt1.04 times the limit	8.3 ppt
East Alton	East Alton	5,786	PFOA, PFOS	PFOA 12 ppt3.1 times the limit	16 ppt
Dupo	Dupo	4,684	PFOS	PFOS 5.0 ppt1.3 times the limit	5.6 ppt
Abingdon	Abingdon	3,275	PFOA	PFOA 9.3 ppt2.3 times the limit	9.4 ppt

14 more utilities in Illinois had a single sample above a limit but no location average above, so they are not listed; each report shows the sample.

Results: EPA UCMR 5 occurrence data, file of Oct. 15, 2026, samples from Jan. 3, 2023 to June 17, 2026, averaged by sampling location as EPA’s final UCMR 5 data summary does. Every state, and the full data as a CSV; how this list is made. People served is what each utility reports.

Utilities above a limit

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