{"schema_version":"1.2","pwsid":"WI6100329","system_name":"LOYAL WATERWORKS","city":"Loyal","state":"WI","population_served":1308,"source_type":"GW","summary":"LOYAL WATERWORKS serves approximately 1,308 people in Loyal, Wisconsin. Based on contaminant analyses from DNR, EPA ECHO, 0 contaminants have been measured above federal EPA standards (MCL) and 3 exceed health-based guidelines. The most significant finding is Arsenic at 0.001 mg/L, which is 250x 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":"2016-09-30","end":"2026-03-02"},"contaminants_tested":85,"contaminants_detected":20,"exceedances":0,"guideline_exceedances":3,"contaminants":[{"name":"Fluoride (natural)","code":"FLUORIDE","cas_number":"16984-48-8","group":"inorganics","section":"other_detected","measured_value":0.66,"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":"Chlorine (free)","code":"0700","cas_number":null,"group":"disinfectants","section":"other_detected","measured_value":1.01,"unit":"mg/L","sample_date":"2026-03-02","source":"DNR","source_scope":"source_monitoring","health_guideline_value":4,"health_guideline_source":"EPA 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PHG","epa_mcl_value":0.01,"status":"exceeds_guideline","detection_limit":null},{"name":"Barium","code":"BARIUM","cas_number":"7440-39-3","group":"inorganics","section":"other_detected","measured_value":0.0441,"unit":"mg/L","sample_date":"2026-02-24","source":"DNR","source_scope":"source_monitoring","health_guideline_value":1,"health_guideline_source":"OEHHA PHG 2003 (hypertension endpoint)","epa_mcl_value":2,"status":"below_limits","detection_limit":null},{"name":"Combined Radium (226+228)","code":"4010","cas_number":null,"group":"radionuclides","section":"other_detected","measured_value":1.1,"unit":"pCi/L","sample_date":"2026-02-24","source":"DNR","source_scope":"source_monitoring","health_guideline_value":0,"health_guideline_source":"EPA 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N)","code":"NITRATE","cas_number":"14797-55-8","group":"inorganics","section":"other_detected","measured_value":5.3,"unit":"mg/L","sample_date":"2026-02-24","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":"Total Trihalomethanes (TTHMs)","code":"2950","cas_number":null,"group":"dbps","section":"other_detected","measured_value":19.73,"unit":"ug/L","sample_date":"2025-08-13","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":"Haloacetic Acids (HAA5)","code":"2456","cas_number":null,"group":"dbps","section":"other_detected","measured_value":24.48,"unit":"ug/L","sample_date":"2025-08-13","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":"Atrazine","code":"2050","cas_number":null,"group":"vocs","section":"other_detected","measured_value":0.0065,"unit":"ug/L","sample_date":"2023-05-08","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":"Lead (90th Percentile)","code":"PB90","cas_number":"7439-92-1","group":"lead_copper","section":"other_detected","measured_value":0,"unit":"mg/L","sample_date":"2023-09-30","source":"EPA ECHO","source_scope":"federal_program","health_guideline_value":0.0002,"health_guideline_source":"OEHHA 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Not a current MCL."},"well_counts":{"active":7,"retired":1,"facilities_synced_at":"2026-04-11T13:48:07.246Z"},"historical_wells":[],"has_only_historical_data":false,"pfas_hazard_index":{"value":0.0924,"compounds_used":["PFHXS","PFBS"],"is_partial":true,"threshold":1,"components":[{"code":"PFHXS","value_ng_l":0.92,"hbwc_ng_l":10,"ratio":0.092},{"code":"PFBS","value_ng_l":0.868,"hbwc_ng_l":2000,"ratio":0.0004}]},"tthm_lraa":[{"monitoring_point":"system_wide","value":19.73,"unit":"ug/L","quarters_used":["2022Q3","2023Q3","2024Q3","2025Q3"],"sample_count":4,"mcl":80,"exceeds_mcl":false}],"haa5_lraa":[{"monitoring_point":"system_wide","value":24.48,"unit":"ug/L","quarters_used":["2022Q3","2023Q3","2024Q3","2025Q3"],"sample_count":4,"mcl":60,"exceeds_mcl":false}]}