{"schema_version":"1.2","pwsid":"WI6420297","system_name":"SPARTA WATERWORKS","city":"Sparta","state":"WI","population_served":10025,"source_type":"GW","summary":"SPARTA WATERWORKS serves approximately 10,025 people in Sparta, Wisconsin. 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 0.0016 mg/L, which is 400x 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":"2014-08-19","end":"2026-03-02"},"contaminants_tested":151,"contaminants_detected":18,"exceedances":0,"guideline_exceedances":3,"contaminants":[{"name":"Chlorine (free)","code":"0700","cas_number":null,"group":"disinfectants","section":"other_detected","measured_value":0.6,"unit":"mg/L","sample_date":"2026-03-02","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":"Fluoride (natural)","code":"FLUORIDE","cas_number":"16984-48-8","group":"inorganics","section":"other_detected","measured_value":0.757,"unit":"mg/L","sample_date":"2026-03-02","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":"Chloromethane","code":"CHLOROMETHANE","cas_number":null,"group":"vocs","section":"other_detected","measured_value":1.53,"unit":"ug/L","sample_date":"2023-01-12","source":"DNR","source_scope":"source_monitoring","health_guideline_value":null,"health_guideline_source":null,"epa_mcl_value":null,"status":"detected","detection_limit":null},{"name":"Bromomethane","code":"BROMOMETHANE","cas_number":null,"group":"vocs","section":"other_detected","measured_value":2.88,"unit":"ug/L","sample_date":"2023-01-12","source":"DNR","source_scope":"source_monitoring","health_guideline_value":null,"health_guideline_source":null,"epa_mcl_value":null,"status":"detected","detection_limit":null},{"name":"Selenium","code":"1045","cas_number":null,"group":"inorganics","section":"other_detected","measured_value":0.0024,"unit":"mg/L","sample_date":"2026-01-06","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.05,"health_guideline_source":"EPA MCLG","epa_mcl_value":0.05,"status":"below_limits","detection_limit":null},{"name":"Nitrate (as N)","code":"NITRATE","cas_number":"14797-55-8","group":"inorganics","section":"other_detected","measured_value":5.75,"unit":"mg/L","sample_date":"2026-01-06","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":"Thallium","code":"1038","cas_number":null,"group":"inorganics","section":"other_detected","measured_value":0.000164,"unit":"mg/L","sample_date":"2026-01-06","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.0005,"health_guideline_source":"EPA MCLG","epa_mcl_value":0.002,"status":"below_limits","detection_limit":null},{"name":"Arsenic","code":"ARSENIC","cas_number":"7440-38-2","group":"inorganics","section":"guideline_exceedance","measured_value":0.0016,"unit":"mg/L","sample_date":"2026-01-06","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.000004,"health_guideline_source":"OEHHA PHG","epa_mcl_value":0.01,"status":"exceeds_guideline","detection_limit":null},{"name":"Uranium","code":"4006","cas_number":"7440-61-1","group":"radionuclides","section":"guideline_exceedance","measured_value":0.571,"unit":"ug/L","sample_date":"2026-01-06","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":3.83,"unit":"pCi/L","sample_date":"2026-01-06","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":"Nickel","code":"1036","cas_number":null,"group":"inorganics","section":"other_detected","measured_value":0.004073,"unit":"mg/L","sample_date":"2026-01-06","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.012,"health_guideline_source":"OEHHA PHG","epa_mcl_value":null,"status":"below_limits","detection_limit":null},{"name":"Barium","code":"BARIUM","cas_number":"7440-39-3","group":"inorganics","section":"other_detected","measured_value":0.05591,"unit":"mg/L","sample_date":"2026-01-06","source":"DNR","source_scope":"source_monitoring","health_guideline_value":1,"health_guideline_source":"OEHHA PHG 2003 (hypertension 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MCLG","epa_mcl_value":4,"status":"below_limits","detection_limit":null},{"name":"Atrazine","code":"2050","cas_number":null,"group":"vocs","section":"other_detected","measured_value":0.023,"unit":"ug/L","sample_date":"2023-04-04","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.00015,"health_guideline_source":"OEHHA PHG 1999","epa_mcl_value":0.003,"status":"below_limits","detection_limit":null},{"name":"Total Trihalomethanes (TTHMs)","code":"2950","cas_number":null,"group":"dbps","section":"other_detected","measured_value":10.54,"unit":"ug/L","sample_date":"2022-07-14","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":"Lead (90th Percentile)","code":"PB90","cas_number":"7439-92-1","group":"lead_copper","section":"guideline_exceedance","measured_value":0.0014,"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":68.2,"unit":"ug/L","sample_date":"2023-06-16","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/"},{"name":"EPA UCMR5","url":"https://www.epa.gov/dwucmr/fifth-unregulated-contaminant-monitoring-rule"}],"pfas_combined_display":null,"well_counts":{"active":6,"retired":4,"facilities_synced_at":"2026-04-11T13:48:07.246Z"},"historical_wells":[],"has_only_historical_data":false,"pfas_hazard_index":null,"tthm_lraa":[],"haa5_lraa":[]}