{"schema_version":"1.2","pwsid":"WI4240219","system_name":"PRINCETON WATERWORKS","city":"PRINCETON","state":"WI","population_served":1166,"source_type":"GW","summary":"PRINCETON WATERWORKS serves approximately 1,166 people in PRINCETON, 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 7.815 pCi/L, which is 1.6x the EPA legal limit. Data is drawn from source-level compliance monitoring and covers 1995 through 2026. Results reflect conditions at the point of collection (wells, treatment plants), not necessarily at the tap.","data_period":{"start":"1995-06-12","end":"2026-03-23"},"contaminants_tested":75,"contaminants_detected":16,"exceedances":1,"guideline_exceedances":3,"contaminants":[{"name":"Chloramines","code":"0600","cas_number":null,"group":"disinfectants","section":"other_detected","measured_value":0.05,"unit":"mg/L","sample_date":"2026-03-23","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 (free)","code":"0700","cas_number":null,"group":"disinfectants","section":"other_detected","measured_value":0.6,"unit":"mg/L","sample_date":"2026-03-23","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 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PHG","epa_mcl_value":0.03,"status":"exceeds_guideline","detection_limit":null},{"name":"Gross Beta","code":"4002","cas_number":null,"group":"radionuclides","section":"other_detected","measured_value":5.85,"unit":"pCi/L","sample_date":"2025-09-23","source":"DNR","source_scope":"source_monitoring","health_guideline_value":null,"health_guideline_source":null,"epa_mcl_value":50,"status":"below_limits","detection_limit":null},{"name":"Combined Radium (226+228)","code":"4010","cas_number":null,"group":"radionuclides","section":"legal_violation","measured_value":7.815,"unit":"pCi/L","sample_date":"2025-09-23","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0,"health_guideline_source":"EPA MCLG","epa_mcl_value":5,"status":"exceeds_legal_limit","detection_limit":null},{"name":"Gross Alpha Radiation (excluding Radon and Uranium)","code":"4000_EXCL","cas_number":null,"group":"radionuclides","section":"other_detected","measured_value":9.03,"unit":"pCi/L","sample_date":"2025-09-23","source":"DNR","source_scope":"source_monitoring","health_guideline_value":null,"health_guideline_source":null,"epa_mcl_value":15,"status":"below_limits","detection_limit":null},{"name":"1,2,4-Trimethylbenzene","code":"1_2_4_TRIMETHYLBENZENE","cas_number":null,"group":"vocs","section":"other_detected","measured_value":0.13,"unit":"ug/L","sample_date":"2025-09-17","source":"DNR","source_scope":"source_monitoring","health_guideline_value":null,"health_guideline_source":null,"epa_mcl_value":null,"status":"detected","detection_limit":null},{"name":"Ethylbenzene","code":"2966","cas_number":null,"group":"other","section":"other_detected","measured_value":0.16,"unit":"ug/L","sample_date":"2025-09-17","source":"DNR","source_scope":"source_monitoring","health_guideline_value":null,"health_guideline_source":null,"epa_mcl_value":null,"status":"detected","detection_limit":null},{"name":"N-Hexane","code":"N_HEXANE","cas_number":null,"group":"vocs","section":"other_detected","measured_value":0.38,"unit":"ug/L","sample_date":"2025-09-17","source":"DNR","source_scope":"source_monitoring","health_guideline_value":null,"health_guideline_source":null,"epa_mcl_value":null,"status":"detected","detection_limit":null},{"name":"Haloacetic Acids (HAA5)","code":"2456","cas_number":null,"group":"dbps","section":"other_detected","measured_value":0.18,"unit":"ug/L","sample_date":"2025-09-17","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":"Total Trihalomethanes (TTHMs)","code":"2950","cas_number":null,"group":"dbps","section":"other_detected","measured_value":1.8,"unit":"ug/L","sample_date":"2025-09-17","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":"Fluoride (natural)","code":"FLUORIDE","cas_number":"16984-48-8","group":"inorganics","section":"other_detected","measured_value":0.0825,"unit":"mg/L","sample_date":"2023-06-20","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":"Barium","code":"BARIUM","cas_number":"7440-39-3","group":"inorganics","section":"other_detected","measured_value":0.174,"unit":"mg/L","sample_date":"2023-06-20","source":"DNR","source_scope":"source_monitoring","health_guideline_value":1,"health_guideline_source":"OEHHA PHG 2003 (hypertension 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ECHO","url":"https://echo.epa.gov/"}],"pfas_combined_display":null,"well_counts":{"active":2,"retired":0,"facilities_synced_at":"2026-04-11T13:48:07.246Z"},"historical_wells":[],"has_only_historical_data":false,"pfas_hazard_index":null,"tthm_lraa":[{"monitoring_point":"system_wide","value":1.8,"unit":"ug/L","quarters_used":["2022Q3","2023Q3","2024Q3","2025Q3"],"sample_count":4,"mcl":80,"exceeds_mcl":false}],"haa5_lraa":[{"monitoring_point":"system_wide","value":0.18,"unit":"ug/L","quarters_used":["2022Q3","2023Q3","2024Q3","2025Q3"],"sample_count":4,"mcl":60,"exceeds_mcl":false}]}