{"schema_version":"1.2","pwsid":"WI7370163","system_name":"WESTON MUNICIPAL UTILITIES","city":"WESTON","state":"WI","population_served":16000,"source_type":"GW","summary":"WESTON MUNICIPAL UTILITIES serves approximately 16,000 people in WESTON, Wisconsin. Based on contaminant analyses from DNR, WQP, EPA ECHO, EPA UCMR5, 1 contaminant has been measured above federal EPA standards (MCL) and 4 exceed health-based guidelines. The most significant finding is PFOA (Perfluorooctanoic Acid) at 0.0059 ug/L, which is 1.5x the EPA legal limit. Data is drawn from source-level compliance monitoring and covers 2002 through 2026. Results reflect conditions at the point of collection (wells, treatment plants), not necessarily at the tap.","data_period":{"start":"2002-08-12","end":"2026-03-18"},"contaminants_tested":106,"contaminants_detected":31,"exceedances":1,"guideline_exceedances":4,"contaminants":[{"name":"Chlorine (free)","code":"0700","cas_number":null,"group":"disinfectants","section":"other_detected","measured_value":0.61,"unit":"mg/L","sample_date":"2026-03-18","source":"DNR","source_scope":"source_monitoring","health_guideline_value":4,"health_guideline_source":"EPA 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Not a current MCL."},"well_counts":{"active":7,"retired":3,"facilities_synced_at":"2026-04-11T13:48:07.246Z"},"historical_wells":[{"state_facility_id":"3","facility_name":"VX771","deactivation_date":"2026-02-24","top_contaminant":"PFOS (Perfluorooctane Sulfonate)","top_contaminant_code":"PFOS","max_value":47.4,"unit":"ng/L","classification":"above_mcl","mcl_or_phg_value":4,"mcl_or_phg_unit":"ng/L","validated_reason":null}],"has_only_historical_data":false,"pfas_hazard_index":{"value":0.1518,"compounds_used":["PFHXS","PFNA","PFBS"],"is_partial":true,"threshold":1,"components":[{"code":"PFHXS","value_ng_l":0.72,"hbwc_ng_l":10,"ratio":0.072},{"code":"PFNA","value_ng_l":0.76,"hbwc_ng_l":10,"ratio":0.076},{"code":"PFBS","value_ng_l":7.6,"hbwc_ng_l":2000,"ratio":0.0038}]},"tthm_lraa":[{"monitoring_point":"system_wide","value":23.74,"unit":"ug/L","quarters_used":["2022Q3","2023Q3","2024Q3","2025Q3"],"sample_count":8,"mcl":80,"exceeds_mcl":false}],"haa5_lraa":[{"monitoring_point":"system_wide","value":5.41,"unit":"ug/L","quarters_used":["2022Q3","2023Q3","2024Q3","2025Q3"],"sample_count":8,"mcl":60,"exceeds_mcl":false}]}