Ameren-Missouri — NPDES permit MO0000361: limits, due date and EPA's record

NPDES permit MO0000361 · Major NON-POTW · effective, expires 2029-05-31 · EPA's file as of 2026-09-19

EPA's record, 2025-09-01 to 2026-08-31

Reporting

Reports are due about 28 days after each monitoring period ends (the most common figure among MO permits in EPA's filings — check your permit).

Limits in force (16)

Outfall	Parameter	Statistic	Limit	Months
003	pH	MINIMUM	>= 6.5 SU	all year
003	pH	MAXIMUM	<= 9 SU	all year
003	Solids, total suspended	DAILY MX	<= 100 mg/L	all year
003	Solids, total suspended	MO AVG	<= 30 mg/L	all year
003	Oil and grease [soxhlet extr.] tot.	DAILY MX	<= 15 mg/L	all year
003	Oil and grease [soxhlet extr.] tot.	MO AVG	<= 10 mg/L	all year
003	Boron, total recoverable	DAILY MX	<= 2000 ug/L	all year
003	Boron, total recoverable	MO AVG	report only	all year
003	Chromium, total [as Cr]	DAILY MX	report only	all year
003	Chromium, total [as Cr]	MO AVG	report only	all year
003	Aluminum, total recoverable	DAILY MX	<= 1865 ug/L	all year
003	Aluminum, total recoverable	MO AVG	report only	all year
003	Chromium, hexavalent dissolved [as Cr]	DAILY MX	<= 50 ug/L	all year
003	Chromium, hexavalent dissolved [as Cr]	MO AVG	report only	all year
003	Flow, in conduit or thru treatment plant	DAILY MX	report only	all year
003	Flow, in conduit or thru treatment plant	MO AVG	report only	all year