{"schema_version":"1.2","pwsid":"MN1020034","system_name":"Andover","city":"Andover","state":"MN","population_served":21455,"source_type":"GW","summary":"Andover serves approximately 21,455 people in Andover, Minnesota. Based on contaminant analyses from DNR, WQP, EPA ECHO, EPA UCMR5, 2 contaminants have been measured above federal EPA standards (MCL) and 2 exceed health-based guidelines. The most significant finding is Gross Alpha at 38 pCi/L, which is 2.5x the EPA legal limit. Data is drawn from source-level compliance monitoring and covers 1995 through 2026. Results reflect conditions at the point of collection (wells, treatment plants), not necessarily at the tap.","data_period":{"start":"1995-11-08","end":"2026-12-31"},"contaminants_tested":40,"contaminants_detected":14,"exceedances":2,"guideline_exceedances":2,"contaminants":[{"name":"Haloacetic Acids (HAA5)","code":"2456","cas_number":null,"group":"dbps","section":"other_detected","measured_value":10.6,"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":0.35,"unit":"mg/L","sample_date":"2025-12-31","source":"DNR","source_scope":"source_monitoring","health_guideline_value":10,"health_guideline_source":"EPA 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