{"permit":"SC0029408","name":"GRAND STRAND WATER & SEWER AUTHORITY","state":"SC","as_of":"2026-10-22","source":{"publisher":"U.S. EPA — ECHO / ICIS-NPDES national file","as_of":"2026-10-22","page":"/dmr/p/SC0029408"},"about":[{"label":"What it is","text":"Sewage treatment plant · rated a major discharger by EPA"},{"label":"Where","text":"Mullins, South Carolina","href":"https://www.openstreetmap.org/?mlat=34.1690508&mlon=-79.217179#map=14/34.1690508/-79.217179"},{"label":"Last 12 months","text":"No values over a limit. 10 required values not reported"},{"label":"Permit","text":"Expired Oct 31, 2023; 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":"2023-05-04","price":"free while piloted","order_page":"https://passage-data.com/dmr/p/SC0029408#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":"2026-09-30","over":0,"over_by":[],"window":["2025-10-01","2026-09-30"]},"over_limits":[],"limits":[{"outfall":"001","parameter":"Oxygen, dissolved [DO]","parameter_code":"00300","statistic":"minimum","qualifier":">=","value":"6","unit":"mg/L","report_only":false,"enforceable":true,"months":"all","limit_set":"0011"},{"outfall":"001","parameter":"pH","parameter_code":"00400","statistic":"minimum","qualifier":">=","value":"6","unit":"SU","report_only":false,"enforceable":true,"months":"all","limit_set":"0011"},{"outfall":"001","parameter":"pH","parameter_code":"00400","statistic":"maximum","qualifier":"<=","value":"8.5","unit":"SU","report_only":false,"enforceable":true,"months":"all","limit_set":"0011"},{"outfall":"001","parameter":"Solids, total suspended","parameter_code":"00530","statistic":"monthly 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permit's limit for that period, with EPA's violation rule's verdict.","arguments":{"permit":"SC0029408"},"needs":{"period_end":"The reporting period: its month (2026-09).","values":"The period's values as your user will file them: [{outfall, parameter, statistic, value, unit}, ...]."},"post":"/api/v1/dmr/check","url":"https://passage-data.com/api/v1/dmr/check","page":"https://passage-data.com/dmr/?permit=SC0029408"},{"tool":"fill_dmr","says":"Has your user the plant's raw daily results? fill_dmr computes the period's DMR values from them, each with the rows it came from.","arguments":{"permit":"SC0029408"},"needs":{"period_end":"The reporting period: its month (2026-09).","rows":"The plant's results: [{date, parameter, value, unit, point}, ...]; or `table`, the lab's or plant's export as text."},"post":"/api/v1/dmr/fill","url":"https://passage-data.com/api/v1/dmr/fill","page":"https://passage-data.com/dmr/?permit=SC0029408"}]}