{"schema_version":"1.2","pwsid":"WI4240223","system_name":"GREEN LAKE MHP","city":"GREEN LAKE","state":"WI","population_served":70,"source_type":"GW","summary":"GREEN LAKE MHP serves approximately 70 people in GREEN LAKE, Wisconsin. Based on contaminant analyses from DNR, EPA ECHO, 0 contaminants have been measured above federal EPA standards (MCL) and 2 exceed health-based guidelines. The most significant finding is Lead (90th Percentile) at 0.00075 mg/L, which is 3.8x the health guideline. Data is drawn from source-level compliance monitoring and covers 2018 through 2026. Results reflect conditions at the point of collection (wells, treatment plants), not necessarily at the tap.","data_period":{"start":"2018-09-30","end":"2026-01-20"},"contaminants_tested":16,"contaminants_detected":8,"exceedances":0,"guideline_exceedances":2,"contaminants":[{"name":"Nitrate (as N)","code":"NITRATE","cas_number":"14797-55-8","group":"inorganics","section":"other_detected","measured_value":1.59,"unit":"mg/L","sample_date":"2026-01-20","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":"Pentachlorophenol","code":"2041","cas_number":null,"group":"vocs","section":"other_detected","measured_value":0.17,"unit":"ug/L","sample_date":"2024-03-18","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.009,"health_guideline_source":"WHO Guideline","epa_mcl_value":0.001,"status":"below_limits","detection_limit":null},{"name":"Di(2-ethylhexyl) phthalate","code":"2046","cas_number":null,"group":"vocs","section":"other_detected","measured_value":0.62,"unit":"ug/L","sample_date":"2024-04-24","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0.008,"health_guideline_source":"WHO Guideline","epa_mcl_value":0.006,"status":"below_limits","detection_limit":null},{"name":"Combined Radium (226+228)","code":"4010","cas_number":null,"group":"radionuclides","section":"other_detected","measured_value":0.45,"unit":"pCi/L","sample_date":"2021-01-15","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":"Gross Alpha Radiation (excluding Radon and Uranium)","code":"4000_EXCL","cas_number":null,"group":"radionuclides","section":"other_detected","measured_value":0.56,"unit":"pCi/L","sample_date":"2021-01-15","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":"Uranium","code":"4006","cas_number":"7440-61-1","group":"radionuclides","section":"guideline_exceedance","measured_value":0.96,"unit":"ug/L","sample_date":"2021-01-15","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":0.00075,"unit":"mg/L","sample_date":"2024-09-30","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":84.2,"unit":"ug/L","sample_date":"2024-09-12","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":"EPA ECHO","url":"https://echo.epa.gov/"}],"pfas_combined_display":null,"well_counts":{"active":1,"retired":1,"facilities_synced_at":"2026-09-05T13:11:48.807Z"},"historical_wells":[],"has_only_historical_data":false,"pfas_hazard_index":null,"tthm_lraa":[],"haa5_lraa":[]}