{"schema_version":"1.2","pwsid":"IL1194280","system_name":"COLLINSVILLE","city":"COLLINSVILLE","state":"IL","population_served":29500,"source_type":"GW","summary":"COLLINSVILLE serves approximately 29,500 people in COLLINSVILLE, Illinois. Based on contaminant analyses from EPA ECHO, EPA UCMR5, 3 contaminants have been measured above federal EPA standards (MCL) and 4 exceed health-based guidelines. The most significant finding is PFOA (Perfluorooctanoic Acid) at 0.018 ug/L, which is 4.5x the EPA legal limit. Data is drawn from source-level compliance monitoring and covers 2017 through 2025. Results reflect conditions at the point of collection (wells, treatment plants), not necessarily at the tap.","data_period":{"start":"2017-12-31","end":"2025-12-31"},"contaminants_tested":31,"contaminants_detected":9,"exceedances":3,"guideline_exceedances":4,"contaminants":[{"name":"Lead (90th Percentile)","code":"PB90","cas_number":"7439-92-1","group":"lead_copper","section":"guideline_exceedance","measured_value":0.0045,"unit":"mg/L","sample_date":"2025-12-31","source":"EPA ECHO","source_scope":"federal_program","health_guideline_value":0.0002,"health_guideline_source":"OEHHA PHG","epa_mcl_value":null,"status":"exceeds_guideline","detection_limit":null},{"name":"PFBA (Perfluorobutanoic Acid)","code":"PFBA","cas_number":null,"group":"pfas","section":"pfas","measured_value":0.013,"unit":"ug/L","sample_date":"2024-08-01","source":"EPA UCMR5","source_scope":"federal_program","health_guideline_value":null,"health_guideline_source":null,"epa_mcl_value":null,"status":"detected","detection_limit":0.005},{"name":"Pfhxa","code":"PFHxA","cas_number":null,"group":"other","section":"pfas","measured_value":0.022,"unit":"ug/L","sample_date":"2024-08-01","source":"EPA UCMR5","source_scope":"federal_program","health_guideline_value":null,"health_guideline_source":null,"epa_mcl_value":null,"status":"detected","detection_limit":0.003},{"name":"Pfpea","code":"PFPeA","cas_number":null,"group":"other","section":"pfas","measured_value":0.021,"unit":"ug/L","sample_date":"2024-08-01","source":"EPA UCMR5","source_scope":"federal_program","health_guideline_value":null,"health_guideline_source":null,"epa_mcl_value":null,"status":"detected","detection_limit":0.003},{"name":"PFOA (Perfluorooctanoic Acid)","code":"PFOA","cas_number":"335-67-1","group":"pfas","section":"legal_violation","measured_value":0.018,"unit":"ug/L","sample_date":"2024-08-01","source":"EPA UCMR5","source_scope":"federal_program","health_guideline_value":0,"health_guideline_source":"EPA MCLG","epa_mcl_value":0.004,"status":"exceeds_legal_limit","detection_limit":0.004},{"name":"PFOS (Perfluorooctane Sulfonate)","code":"PFOS","cas_number":"1763-23-1","group":"pfas","section":"legal_violation","measured_value":0.0089,"unit":"ug/L","sample_date":"2024-08-01","source":"EPA UCMR5","source_scope":"federal_program","health_guideline_value":0,"health_guideline_source":"EPA MCLG","epa_mcl_value":0.004,"status":"exceeds_legal_limit","detection_limit":0.004},{"name":"PFHxS (Perfluorohexane Sulfonate)","code":"PFHXS","cas_number":"355-46-4","group":"pfas","section":"legal_violation","measured_value":0.012,"unit":"ug/L","sample_date":"2024-08-01","source":"EPA UCMR5","source_scope":"federal_program","health_guideline_value":0.01,"health_guideline_source":"EPA MCLG","epa_mcl_value":0.01,"status":"exceeds_legal_limit","detection_limit":0.003},{"name":"PFBS (Perfluorobutane Sulfonate)","code":"PFBS","cas_number":"375-73-5","group":"pfas","section":"pfas","measured_value":0.016,"unit":"ug/L","sample_date":"2024-08-01","source":"EPA UCMR5","source_scope":"federal_program","health_guideline_value":null,"health_guideline_source":null,"epa_mcl_value":null,"status":"detected","detection_limit":0.003},{"name":"Pfhpa","code":"PFHpA","cas_number":null,"group":"other","section":"pfas","measured_value":0.013,"unit":"ug/L","sample_date":"2024-08-01","source":"EPA UCMR5","source_scope":"federal_program","health_guideline_value":null,"health_guideline_source":null,"epa_mcl_value":null,"status":"detected","detection_limit":0.003}],"sources":[{"name":"EPA ECHO","url":"https://echo.epa.gov/"},{"name":"EPA UCMR5","url":"https://www.epa.gov/dwucmr/fifth-unregulated-contaminant-monitoring-rule"}],"pfas_combined_display":null,"well_counts":{"active":6,"retired":3,"facilities_synced_at":"2026-09-06T14:49:36.593Z"},"historical_wells":[],"has_only_historical_data":false,"pfas_hazard_index":{"value":1.208,"compounds_used":["PFHXS","PFBS"],"is_partial":true,"threshold":1,"components":[{"code":"PFHXS","value_ng_l":12,"hbwc_ng_l":10,"ratio":1.2},{"code":"PFBS","value_ng_l":16,"hbwc_ng_l":2000,"ratio":0.008}]},"tthm_lraa":[],"haa5_lraa":[]}