{"schema_version":"1.2","pwsid":"IL1110050","system_name":"ALGONQUIN","city":"ALGONQUIN","state":"IL","population_served":30700,"source_type":"GW","summary":"ALGONQUIN serves approximately 30,700 people in ALGONQUIN, 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 Arsenic at 0.00103 mg/L, which is 257.5x the health guideline. Data is drawn from source-level compliance monitoring and covers 1996 through 2028. Results reflect conditions at the point of collection (wells, treatment plants), not necessarily at the tap.","data_period":{"start":"1996-08-06","end":"2028-12-31"},"contaminants_tested":43,"contaminants_detected":17,"exceedances":0,"guideline_exceedances":3,"contaminants":[{"name":"Haloacetic Acids (HAA5)","code":"2456","cas_number":null,"group":"dbps","section":"other_detected","measured_value":20,"unit":"ug/L","sample_date":"2026-07-28","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.0001,"health_guideline_source":"EWG Health Guideline","epa_mcl_value":0.06,"status":"below_limits","detection_limit":null},{"name":"Barium","code":"BARIUM","cas_number":"7440-39-3","group":"inorganics","section":"other_detected","measured_value":0.12,"unit":"mg/L","sample_date":"2026-07-21","source":"DNR","source_scope":"source_monitoring","health_guideline_value":1,"health_guideline_source":"OEHHA PHG 2003 (hypertension 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