{"schema_version":"1.2","pwsid":"IL1970250","system_name":"CREST HILL","city":"CREST HILL","state":"IL","population_served":20223,"source_type":"GW","summary":"CREST HILL serves approximately 20,223 people in CREST HILL, Illinois. Based on contaminant analyses from DNR, WQP, EPA ECHO, EPA UCMR5, 3 contaminants have been measured above federal EPA standards (MCL) and 6 exceed health-based guidelines. The most significant finding is PFOA (Perfluorooctanoic Acid) at 0.0137 ug/L, which is 3.4x the EPA legal limit. Data is drawn from source-level compliance monitoring and covers 2007 through 2026. 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