{"schema_version":"1.2","pwsid":"WI1130224","system_name":"MADISON WATER UTILITY","city":"MADISON","state":"WI","population_served":272000,"source_type":"GW","summary":"MADISON WATER UTILITY serves approximately 272,000 people in MADISON, Wisconsin. Based on contaminant analyses from DNR, WQP, EPA ECHO, EPA UCMR5, 3 contaminants have been measured above federal EPA standards (MCL) and 8 exceed health-based guidelines. The most significant finding is PFHxS (Perfluorohexane Sulfonate) at 23 ng/L, which is 2.3x the EPA legal limit. Data is drawn from source-level compliance monitoring and covers 2014 through 2026. 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