{"schema_version":"1.2","pwsid":"MN1190019","system_name":"Rosemount","city":"Rosemount","state":"MN","population_served":26500,"source_type":"GW","summary":"Rosemount serves approximately 26,500 people in Rosemount, Minnesota. Based on contaminant analyses from DNR, EPA ECHO, EPA UCMR5, the most recent monitoring readings are within federal EPA standards (MCL), but this system has active MCL violations on record for 1 contaminant. 4 contaminants exceed health-based guidelines. The most significant finding is Lead (90th Percentile) at 0.003 mg/L, which is 15x the health guideline. Data is drawn from source-level compliance monitoring and covers 2016 through 2026. Results reflect conditions at the point of collection (wells, treatment plants), not necessarily at the tap.","data_period":{"start":"2016-12-31","end":"2026-09-05"},"contaminants_tested":39,"contaminants_detected":10,"exceedances":0,"guideline_exceedances":4,"contaminants":[{"name":"Arsenic","code":"ARSENIC","cas_number":"7440-38-2","group":"inorganics","section":"guideline_exceedance","measured_value":0.0005,"unit":"mg/L","sample_date":"2025-12-31","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":"Haloacetic Acids (HAA5)","code":"2456","cas_number":null,"group":"dbps","section":"other_detected","measured_value":3.18,"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":5.1,"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":"Tetrachloroethylene (PCE)","code":"2987","cas_number":null,"group":"vocs","section":"guideline_exceedance","measured_value":0.1,"unit":"ug/L","sample_date":"2025-12-31","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.00006,"health_guideline_source":"OEHHA PHG","epa_mcl_value":0.005,"status":"exceeds_guideline","detection_limit":null},{"name":"Combined Radium (226+228)","code":"4010","cas_number":null,"group":"radionuclides","section":"other_detected","measured_value":4.75,"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":"approaching","detection_limit":null},{"name":"Trichloroethylene (TCE)","code":"2984","cas_number":null,"group":"vocs","section":"other_detected","measured_value":0.05,"unit":"ug/L","sample_date":"2025-12-31","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.0017,"health_guideline_source":"OEHHA PHG","epa_mcl_value":0.005,"status":"below_limits","detection_limit":null},{"name":"Total Trihalomethanes (TTHMs)","code":"2950","cas_number":null,"group":"dbps","section":"other_detected","measured_value":12.01,"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":"Uranium","code":"4006","cas_number":"7440-61-1","group":"radionuclides","section":"guideline_exceedance","measured_value":2.687,"unit":"ug/L","sample_date":"2025-12-31","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":"Lead (90th Percentile)","code":"PB90","cas_number":"7439-92-1","group":"lead_copper","section":"guideline_exceedance","measured_value":0.003,"unit":"mg/L","sample_date":"2025-12-31","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":"PFBA (Perfluorobutanoic Acid)","code":"PFBA","cas_number":null,"group":"pfas","section":"pfas","measured_value":72,"unit":"ng/L","sample_date":"2026-09-05","source":"DNR","source_scope":"source_monitoring","health_guideline_value":null,"health_guideline_source":null,"epa_mcl_value":null,"status":"detected","detection_limit":null}],"sources":[{"name":"DNR","url":"https://apps.dnr.wi.gov/dwsportalpub"},{"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":9,"retired":1,"facilities_synced_at":"2026-09-06T14:49:14.849Z"},"historical_wells":[],"has_only_historical_data":false,"pfas_hazard_index":null,"tthm_lraa":[{"monitoring_point":"system_wide","value":12.01,"unit":"ug/L","quarters_used":["2022Q4","2023Q4","2024Q4","2025Q4"],"sample_count":5,"mcl":80,"exceeds_mcl":false}],"haa5_lraa":[{"monitoring_point":"system_wide","value":3.18,"unit":"ug/L","quarters_used":["2022Q4","2023Q4","2024Q4","2025Q4"],"sample_count":5,"mcl":60,"exceeds_mcl":false}]}