{"schema_version":"1.2","pwsid":"IL1615387","system_name":"ROCK ISLAND ARSENAL, US ARMY","city":"ROCK ISLAND","state":"IL","population_served":7800,"source_type":"SW","summary":"ROCK ISLAND ARSENAL, US ARMY serves approximately 7,800 people in ROCK ISLAND, Illinois. Based on contaminant analyses from EPA ECHO, EPA UCMR5, 1 contaminant has been measured above federal EPA standards (MCL) and 1 exceeds health-based guidelines. The most significant finding is PFOA (Perfluorooctanoic Acid) at 0.0046 ug/L, which is 1.2x the EPA legal limit. Data is drawn from source-level compliance monitoring and covers 2017 through 2023. Results reflect conditions at the point of collection (wells, treatment plants), not necessarily at the tap.","data_period":{"start":"2017-12-31","end":"2023-12-31"},"contaminants_tested":31,"contaminants_detected":3,"exceedances":1,"guideline_exceedances":1,"contaminants":[{"name":"Lead (90th Percentile)","code":"PB90","cas_number":"7439-92-1","group":"lead_copper","section":"other_detected","measured_value":0,"unit":"mg/L","sample_date":"2023-12-31","source":"EPA ECHO","source_scope":"federal_program","health_guideline_value":0.0002,"health_guideline_source":"OEHHA PHG","epa_mcl_value":null,"status":"below_limits","detection_limit":null},{"name":"PFOA (Perfluorooctanoic Acid)","code":"PFOA","cas_number":"335-67-1","group":"pfas","section":"legal_violation","measured_value":0.0046,"unit":"ug/L","sample_date":"2023-11-07","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":"PFBA (Perfluorobutanoic Acid)","code":"PFBA","cas_number":null,"group":"pfas","section":"pfas","measured_value":0.015,"unit":"ug/L","sample_date":"2023-11-07","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}],"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":0,"retired":2,"facilities_synced_at":"2026-09-06T14:49:36.593Z"},"historical_wells":[],"has_only_historical_data":false,"pfas_hazard_index":null,"tthm_lraa":[],"haa5_lraa":[]}