{"schema_version":"1.2","pwsid":"WI2520199","system_name":"SOUTHERN WISCONSIN CENTER","city":"UNION GROVE","state":"WI","population_served":950,"source_type":"GW","summary":"SOUTHERN WISCONSIN CENTER serves approximately 950 people in UNION GROVE, Wisconsin. Based on contaminant analyses from DNR, WQP, EPA ECHO, 1 contaminant has been measured above federal EPA standards (MCL) and 3 exceed health-based guidelines. The most significant finding is Combined Radium (226+228) at 5.29 pCi/L, which is 1.1x the EPA legal limit. Data is drawn from source-level compliance monitoring and covers 2000 through 2026. Results reflect conditions at the point of collection (wells, treatment plants), not necessarily at the tap.","data_period":{"start":"2000-05-02","end":"2026-03-25"},"contaminants_tested":125,"contaminants_detected":18,"exceedances":1,"guideline_exceedances":3,"contaminants":[{"name":"Chlorine (free)","code":"0700","cas_number":null,"group":"disinfectants","section":"other_detected","measured_value":1.41,"unit":"mg/L","sample_date":"2026-03-25","source":"DNR","source_scope":"source_monitoring","health_guideline_value":4,"health_guideline_source":"EPA MCLG","epa_mcl_value":4,"status":"below_limits","detection_limit":null},{"name":"Chlorine (total residual)","code":"0700_TOTAL","cas_number":null,"group":"disinfectants","section":"other_detected","measured_value":1.3,"unit":"mg/L","sample_date":"2026-02-11","source":"DNR","source_scope":"source_monitoring","health_guideline_value":4,"health_guideline_source":"EPA 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(HAA5)","code":"2456","cas_number":null,"group":"dbps","section":"other_detected","measured_value":5.72,"unit":"ug/L","sample_date":"2025-08-13","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":"Ethylbenzene","code":"2966","cas_number":null,"group":"other","section":"other_detected","measured_value":0.13,"unit":"ug/L","sample_date":"2025-08-13","source":"DNR","source_scope":"source_monitoring","health_guideline_value":null,"health_guideline_source":null,"epa_mcl_value":null,"status":"detected","detection_limit":null},{"name":"Total Trihalomethanes (TTHMs)","code":"2950","cas_number":null,"group":"dbps","section":"other_detected","measured_value":9.35,"unit":"ug/L","sample_date":"2025-08-13","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.00015,"health_guideline_source":"EWG Health 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