{"permit":"MT0021920","name":"CITY OF GREAT FALLS                                                             ","state":"MT","as_of":"2026-10-22","source":{"publisher":"U.S. EPA — ECHO / ICIS-NPDES national file","as_of":"2026-10-22","page":"/dmr/p/MT0021920"},"about":[{"label":"What it is","text":"Sewage treatment plant · rated a major discharger by EPA"},{"label":"Where","text":"Great Falls, Montana","href":"https://www.openstreetmap.org/?mlat=47.520833&mlon=-111.298611#map=14/47.520833/-111.298611"},{"label":"Last 12 months","text":"No values over a limit"},{"label":"Permit","text":"Expired Aug 31, 2024; its limits still apply until a new permit is issued, and EPA still expects the reports"}],"renewal_due":null,"renewal_check":{"offered_because":"permit_expired","application_due":"2024-03-04","price":"free while piloted","order_page":"https://passage-data.com/dmr/p/MT0021920#renewal","says":"Each limit a renewal could tighten or add, from the state's water-quality standards and the federal rules for this kind of discharge, each cited to its rule, beside EPA's 12-month record; a rule we do not hold is named, never guessed. A person orders it on the permit's page with their email; it is sent by email within 5 business days."},"sector":null,"limits_from_version":null,"record":{"last_filed":"2026-08-31","over":0,"over_by":[],"window":["2025-10-01","2026-09-30"]},"over_limits":[],"limits":[{"outfall":"003","parameter":"Temperature, water deg. centigrade","parameter_code":"00010","statistic":"monthly average","qualifier":null,"value":null,"unit":"deg C","report_only":true,"enforceable":true,"months":"all","limit_set":"WWTP MONTHLY MONITORING"},{"outfall":"003","parameter":"Temperature, water deg. centigrade","parameter_code":"00010","statistic":"daily maximum","qualifier":null,"value":null,"unit":"deg C","report_only":true,"enforceable":true,"months":"all","limit_set":"WWTP MONTHLY MONITORING"},{"outfall":"003","parameter":"Flow rate","parameter_code":"00056","statistic":"daily average","qualifier":null,"value":null,"unit":"MGD","report_only":true,"enforceable":true,"months":"all","limit_set":"WWTP MONTHLY MONITORING"},{"outfall":"003","parameter":"Flow rate","parameter_code":"00056","statistic":"daily maximum","qualifier":null,"value":null,"unit":"MGD","report_only":true,"enforceable":true,"months":"all","limit_set":"WWTP MONTHLY MONITORING"},{"outfall":"003","parameter":"Flow rate","parameter_code":"00056","statistic":"daily average","qualifier":null,"value":null,"unit":"MGD","report_only":true,"enforceable":true,"months":"all","limit_set":"WWTP MONTHLY MONITORING"},{"outfall":"003","parameter":"Flow rate","parameter_code":"00056","statistic":"daily maximum","qualifier":null,"value":null,"unit":"MGD","report_only":true,"enforceable":true,"months":"all","limit_set":"WWTP MONTHLY MONITORING"},{"outfall":"003","parameter":"Oxygen, dissolved [DO]","parameter_code":"00300","statistic":"single sample","qualifier":null,"value":null,"unit":"mg/L","report_only":true,"enforceable":true,"months":"all","limit_set":"WWTP MONTHLY MONITORING"},{"outfall":"003","parameter":"BOD, 5-day, 20 deg. 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