{"schema_version":"1.2","pwsid":"IL1610550","system_name":"PORT BYRON","city":"PORT BYRON","state":"IL","population_served":1678,"source_type":"GW","summary":"PORT BYRON serves approximately 1,678 people in PORT BYRON, Illinois. Based on contaminant analyses from EPA ECHO, the most recent monitoring readings are within federal EPA standards (MCL), but this system has active MCL violations on record for 1 contaminant. 1 contaminant exceeds health-based guidelines. The most significant finding is Lead (90th Percentile) at 0.0047 mg/L, which is 23.5x the health guideline. Data is drawn from source-level compliance monitoring and covers 2017 through 2026. Results reflect conditions at the point of collection (wells, treatment plants), not necessarily at the tap.","data_period":{"start":"2017-12-31","end":"2026-06-30"},"contaminants_tested":1,"contaminants_detected":1,"exceedances":0,"guideline_exceedances":1,"contaminants":[{"name":"Lead (90th Percentile)","code":"PB90","cas_number":"7439-92-1","group":"lead_copper","section":"guideline_exceedance","measured_value":0.0047,"unit":"mg/L","sample_date":"2026-06-30","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}],"sources":[{"name":"EPA ECHO","url":"https://echo.epa.gov/"}],"pfas_combined_display":null,"well_counts":{"active":3,"retired":1,"facilities_synced_at":"2026-09-06T14:49:36.593Z"},"historical_wells":[],"has_only_historical_data":false,"pfas_hazard_index":null,"tthm_lraa":[],"haa5_lraa":[]}