{"schema_version":"1.2","pwsid":"IL1970500","system_name":"LOCKPORT","city":"LOCKPORT","state":"IL","population_served":23100,"source_type":"GW","summary":"LOCKPORT serves approximately 23,100 people in LOCKPORT, Illinois. Based on contaminant analyses from DNR, WQP, EPA ECHO, EPA UCMR5, 0 contaminants have been measured above federal EPA standards (MCL) and 3 exceed health-based guidelines. The most significant finding is Lead (90th Percentile) at 0.0076 mg/L, which is 38x the health guideline. Data is drawn from source-level compliance monitoring and covers 2007 through 2026. Results reflect conditions at the point of collection (wells, treatment plants), not necessarily at the tap.","data_period":{"start":"2007-10-15","end":"2026-08-11"},"contaminants_tested":43,"contaminants_detected":18,"exceedances":0,"guideline_exceedances":3,"contaminants":[{"name":"Total Trihalomethanes (TTHMs)","code":"2950","cas_number":null,"group":"dbps","section":"other_detected","measured_value":29,"unit":"ug/L","sample_date":"2026-08-11","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.00015,"health_guideline_source":"EWG Health Guideline","epa_mcl_value":0.08,"status":"below_limits","detection_limit":null},{"name":"Haloacetic Acids (HAA5)","code":"2456","cas_number":null,"group":"dbps","section":"other_detected","measured_value":12.4,"unit":"ug/L","sample_date":"2026-08-11","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.0001,"health_guideline_source":"EWG Health 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(226+228)","code":"4010","cas_number":null,"group":"radionuclides","section":"other_detected","measured_value":3.58,"unit":"pCi/L","sample_date":"2026-02-10","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0,"health_guideline_source":"EPA MCLG","epa_mcl_value":5,"status":"below_limits","detection_limit":null},{"name":"Chromium (total)","code":"CHROMIUM","cas_number":"7440-47-3","group":"inorganics","section":"other_detected","measured_value":0.00108,"unit":"mg/L","sample_date":"2026-02-10","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.1,"health_guideline_source":"EPA MCLG","epa_mcl_value":0.1,"status":"below_limits","detection_limit":null},{"name":"Nickel","code":"1036","cas_number":null,"group":"inorganics","section":"other_detected","measured_value":0.00156,"unit":"mg/L","sample_date":"2026-02-10","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.012,"health_guideline_source":"OEHHA 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UCMR5","url":"https://www.epa.gov/dwucmr/fifth-unregulated-contaminant-monitoring-rule"}],"pfas_combined_display":null,"well_counts":{"active":7,"retired":10,"facilities_synced_at":"2026-10-26T01:13:06.376Z"},"historical_wells":[],"has_only_historical_data":false,"pfas_hazard_index":{"value":0.9216,"compounds_used":["PFHXS","PFBS"],"is_partial":true,"threshold":1,"components":[{"code":"PFHXS","value_ng_l":9.2,"hbwc_ng_l":10,"ratio":0.92},{"code":"PFBS","value_ng_l":3.2,"hbwc_ng_l":2000,"ratio":0.0016}]},"tthm_lraa":[],"haa5_lraa":[]}