{"schema_version":"1.2","pwsid":"IL0195425","system_name":"WALNUT GROVE MHC","city":"MARION","state":"IL","population_served":40,"source_type":"GW","summary":"WALNUT GROVE MHC serves approximately 40 people in MARION, Illinois. Based on contaminant analyses from DNR, EPA ECHO, 0 contaminants have been measured above federal EPA standards (MCL) and 0 exceed health-based guidelines. No contaminants were measured above federal EPA standards in recent compliance monitoring. Data is drawn from source-level compliance monitoring and covers 2025 through 2026. Results reflect conditions at the point of collection (wells, treatment plants), not necessarily at the tap.","data_period":{"start":"2025-12-30","end":"2026-03-02"},"contaminants_tested":4,"contaminants_detected":4,"exceedances":0,"guideline_exceedances":0,"contaminants":[{"name":"Gross Beta","code":"4002","cas_number":null,"group":"radionuclides","section":"other_detected","measured_value":2.76,"unit":"pCi/L","sample_date":"2026-03-02","source":"DNR","source_scope":"source_monitoring","health_guideline_value":null,"health_guideline_source":null,"epa_mcl_value":50,"status":"below_limits","detection_limit":null},{"name":"Combined Radium (226+228)","code":"4010","cas_number":null,"group":"radionuclides","section":"other_detected","measured_value":1.24,"unit":"pCi/L","sample_date":"2025-12-30","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","code":"4000","cas_number":null,"group":"radionuclides","section":"other_detected","measured_value":1.99,"unit":"pCi/L","sample_date":"2025-12-30","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0,"health_guideline_source":"EPA MCLG","epa_mcl_value":15,"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":"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":"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":2,"retired":1,"facilities_synced_at":"2026-11-02T01:09:07.370Z"},"historical_wells":[],"has_only_historical_data":false,"pfas_hazard_index":null,"tthm_lraa":[],"haa5_lraa":[]}