{"schema_version":"1.2","pwsid":"WI1250075","system_name":"BARNEVELD WATERWORKS","city":"BARNEVELD","state":"WI","population_served":1258,"source_type":"GW","summary":"BARNEVELD WATERWORKS serves approximately 1,258 people in BARNEVELD, Wisconsin. Based on contaminant analyses from DNR, WQP, 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. 2 contaminants exceed health-based guidelines. The most significant finding is Lead (90th Percentile) at 0.0019 mg/L, which is 9.5x the health guideline. Data is drawn from source-level compliance monitoring and covers 2014 through 2026. Results reflect conditions at the point of collection (wells, treatment plants), not necessarily at the tap.","data_period":{"start":"2014-09-15","end":"2026-03-23"},"contaminants_tested":134,"contaminants_detected":16,"exceedances":0,"guideline_exceedances":2,"contaminants":[{"name":"Fluoride (natural)","code":"FLUORIDE","cas_number":"16984-48-8","group":"inorganics","section":"other_detected","measured_value":0.66,"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":0.94,"unit":"mg/L","sample_date":"2026-03-17","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":"Haloacetic Acids (HAA5)","code":"2456","cas_number":null,"group":"dbps","section":"other_detected","measured_value":0.91,"unit":"ug/L","sample_date":"2025-09-29","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":"Nitrate (as N)","code":"NITRATE","cas_number":"14797-55-8","group":"inorganics","section":"other_detected","measured_value":5,"unit":"mg/L","sample_date":"2025-09-29","source":"DNR","source_scope":"source_monitoring","health_guideline_value":10,"health_guideline_source":"EPA MCLG","epa_mcl_value":10,"status":"below_limits","detection_limit":null},{"name":"Total Trihalomethanes (TTHMs)","code":"2950","cas_number":null,"group":"dbps","section":"other_detected","measured_value":1.79,"unit":"ug/L","sample_date":"2023-08-24","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":"Antimony","code":"1052","cas_number":null,"group":"inorganics","section":"other_detected","measured_value":0.00091,"unit":"mg/L","sample_date":"2023-08-24","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.006,"health_guideline_source":"EPA MCLG","epa_mcl_value":0.006,"status":"below_limits","detection_limit":null},{"name":"Beryllium","code":"1006","cas_number":null,"group":"inorganics","section":"other_detected","measured_value":0.000259,"unit":"mg/L","sample_date":"2021-03-29","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.004,"health_guideline_source":"EPA MCLG","epa_mcl_value":0.004,"status":"below_limits","detection_limit":null},{"name":"Chromium (total)","code":"CHROMIUM","cas_number":"7440-47-3","group":"inorganics","section":"other_detected","measured_value":1.5,"unit":"ug/L","sample_date":"2019-05-15","source":"WQP","source_scope":"regional_groundwater","health_guideline_value":0.1,"health_guideline_source":"EPA MCLG","epa_mcl_value":0.1,"status":"below_limits","detection_limit":null},{"name":"Thallium","code":"1038","cas_number":null,"group":"inorganics","section":"other_detected","measured_value":0.0004,"unit":"mg/L","sample_date":"2021-03-29","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.0005,"health_guideline_source":"EPA MCLG","epa_mcl_value":0.002,"status":"approaching","detection_limit":null},{"name":"Arsenic","code":"ARSENIC","cas_number":"7440-38-2","group":"inorganics","section":"other_detected","measured_value":0.33,"unit":"ug/L","sample_date":"2019-05-15","source":"WQP","source_scope":"regional_groundwater","health_guideline_value":0.000004,"health_guideline_source":"OEHHA PHG","epa_mcl_value":0.01,"status":"exceeds_guideline","detection_limit":null},{"name":"Nitrite (as N)","code":"1041","cas_number":null,"group":"inorganics","section":"other_detected","measured_value":0.002,"unit":"mg/L","sample_date":"2021-03-29","source":"DNR","source_scope":"source_monitoring","health_guideline_value":1,"health_guideline_source":"EPA MCLG","epa_mcl_value":1,"status":"below_limits","detection_limit":null},{"name":"Barium","code":"BARIUM","cas_number":"7440-39-3","group":"inorganics","section":"other_detected","measured_value":0.022,"unit":"mg/L","sample_date":"2024-08-28","source":"DNR","source_scope":"source_monitoring","health_guideline_value":1,"health_guideline_source":"OEHHA PHG 2003 (hypertension endpoint)","epa_mcl_value":2,"status":"below_limits","detection_limit":null},{"name":"Combined Radium (226+228)","code":"4010","cas_number":null,"group":"radionuclides","section":"other_detected","measured_value":0.801,"unit":"pCi/L","sample_date":"2024-08-28","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":"Uranium","code":"4006","cas_number":"7440-61-1","group":"radionuclides","section":"guideline_exceedance","measured_value":0.962,"unit":"ug/L","sample_date":"2024-08-28","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.0005,"health_guideline_source":"OEHHA PHG","epa_mcl_value":0.03,"status":"exceeds_guideline","detection_limit":null},{"name":"Gross Alpha Radiation (excluding Radon and Uranium)","code":"4000_EXCL","cas_number":null,"group":"radionuclides","section":"other_detected","measured_value":1.67,"unit":"pCi/L","sample_date":"2024-08-28","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":"Radon","code":"RADON","cas_number":"10043-92-2","group":"radionuclide","section":"other_detected","measured_value":102.9,"unit":"pCi/L","sample_date":"2024-08-28","source":"DNR","source_scope":"source_monitoring","health_guideline_value":300,"health_guideline_source":"EPA proposed MCL (1999, never finalized)","epa_mcl_value":null,"status":"below_limits","detection_limit":null},{"name":"Lead (90th Percentile)","code":"PB90","cas_number":"7439-92-1","group":"lead_copper","section":"guideline_exceedance","measured_value":0.0019,"unit":"mg/L","sample_date":"2023-09-30","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},{"name":"Copper (90th Percentile)","code":"COPPER","cas_number":"7440-50-8","group":"lead_copper","section":"other_detected","measured_value":96.2,"unit":"ug/L","sample_date":"2023-08-16","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.3,"health_guideline_source":"OEHHA PHG","epa_mcl_value":null,"status":"below_limits","detection_limit":null}],"sources":[{"name":"DNR","url":"https://apps.dnr.wi.gov/dwsportalpub"},{"name":"WQP","url":"https://www.waterqualitydata.us/"},{"name":"EPA 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":1.79,"unit":"ug/L","quarters_used":["2021Q3","2022Q3","2023Q3","2024Q3"],"sample_count":4,"mcl":80,"exceeds_mcl":false}],"haa5_lraa":[{"monitoring_point":"system_wide","value":0.91,"unit":"ug/L","quarters_used":["2022Q3","2023Q3","2024Q3","2025Q3"],"sample_count":4,"mcl":60,"exceeds_mcl":false}]}