{"schema_version":"1.2","pwsid":"MN1650004","system_name":"Danube","city":"Danube","state":"MN","population_served":446,"source_type":"GW","summary":"Danube serves approximately 446 people in Danube, Minnesota. 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. 0 contaminants exceed health-based guidelines. Data is drawn from source-level compliance monitoring and covers 1995 through 2025. Results reflect conditions at the point of collection (wells, treatment plants), not necessarily at the tap.","data_period":{"start":"1995-06-22","end":"2025-12-31"},"contaminants_tested":5,"contaminants_detected":5,"exceedances":0,"guideline_exceedances":0,"contaminants":[{"name":"Haloacetic Acids (HAA5)","code":"2456","cas_number":null,"group":"dbps","section":"other_detected","measured_value":5.23,"unit":"ug/L","sample_date":"2025-12-31","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":0.025,"unit":"mg/L","sample_date":"2025-12-31","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":"Combined Radium (226+228)","code":"4010","cas_number":null,"group":"radionuclides","section":"other_detected","measured_value":2.7,"unit":"pCi/L","sample_date":"2025-12-31","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":"Total Trihalomethanes (TTHMs)","code":"2950","cas_number":null,"group":"dbps","section":"other_detected","measured_value":4.13,"unit":"ug/L","sample_date":"2025-12-31","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":"Barium","code":"BARIUM","cas_number":"7440-39-3","group":"inorganics","section":"other_detected","measured_value":0.217,"unit":"mg/L","sample_date":"2020-07-30","source":"WQP","source_scope":"regional_groundwater","health_guideline_value":1,"health_guideline_source":"OEHHA PHG 2003 (hypertension endpoint)","epa_mcl_value":2,"status":"below_limits","detection_limit":null},{"name":"Arsenic","code":"ARSENIC","cas_number":"7440-38-2","group":"inorganics","section":"other_detected","measured_value":30.6,"unit":"ug/L","sample_date":"2020-07-30","source":"WQP","source_scope":"regional_groundwater","health_guideline_value":0.000004,"health_guideline_source":"OEHHA PHG","epa_mcl_value":0.01,"status":"exceeds_legal_limit","detection_limit":null},{"name":"Fluoride (natural)","code":"FLUORIDE","cas_number":"16984-48-8","group":"inorganics","section":"other_detected","measured_value":0.66,"unit":"mg/L","sample_date":"2020-07-30","source":"WQP","source_scope":"regional_groundwater","health_guideline_value":4,"health_guideline_source":"EPA MCLG","epa_mcl_value":4,"status":"below_limits","detection_limit":null},{"name":"Chromium (total)","code":"CHROMIUM","cas_number":"7440-47-3","group":"inorganics","section":"other_detected","measured_value":1.32,"unit":"ug/L","sample_date":"1995-06-22","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":"Lead (90th Percentile)","code":"PB90","cas_number":"7439-92-1","group":"lead_copper","section":"other_detected","measured_value":0,"unit":"mg/L","sample_date":"2024-12-31","source":"EPA ECHO","source_scope":"federal_program","health_guideline_value":0.0002,"health_guideline_source":"OEHHA PHG","epa_mcl_value":null,"status":"below_limits","detection_limit":null},{"name":"Copper (90th Percentile)","code":"COPPER","cas_number":"7440-50-8","group":"lead_copper","section":"other_detected","measured_value":1.2,"unit":"ug/L","sample_date":"2015-04-27","source":"WQP","source_scope":"regional_groundwater","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":3,"retired":0,"facilities_synced_at":"2026-10-26T01:03:17.192Z"},"historical_wells":[],"has_only_historical_data":false,"pfas_hazard_index":null,"tthm_lraa":[{"monitoring_point":"system_wide","value":4.13,"unit":"ug/L","quarters_used":["2020Q4","2021Q4","2022Q4","2025Q4"],"sample_count":5,"mcl":80,"exceeds_mcl":false}],"haa5_lraa":[{"monitoring_point":"system_wide","value":5.23,"unit":"ug/L","quarters_used":["2018Q4","2019Q4","2022Q4","2025Q4"],"sample_count":5,"mcl":60,"exceeds_mcl":false}]}