MILLSTADT STP, VILLAGE OF
NPDES ID: IL0032514
E — SNC: Effluent violation (monthly average limit)
The facility discharged more of a pollutant than its permit allows, based on a monthly average.
This quarter: 24 effluent violations.
Violations
May 31, 2026
BOD, carbonaceous [5 day, 20 C]
77% over limit
Discharged 35.4 mg/L against a permitted limit of 20 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Coliform, fecal general
25% over limit
Discharged 500 MPN/100mL against a permitted limit of 400 MPN/100mL (DAILY MX)
DMR, Limited - Numeric Violation
Solids, total suspended
124% over limit
Discharged 26.83 mg/L against a permitted limit of 12 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
200% over limit
Discharged 72 mg/L against a permitted limit of 24 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Solids, total suspended
9% over limit
Discharged 182.65418647 kg/d against a permitted limit of 167.0719986 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
153% over limit
Discharged 25.3 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
3% over limit
Discharged 3.09 mg/L against a permitted limit of 3 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
1% over limit
Discharged 1.52 mg/L against a permitted limit of 1.5 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Phosphorus, total [as P]
131% over limit
Discharged 2.31 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
April 30, 2026
Phosphorus, total [as P]
228% over limit
Discharged 3.28 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
134% over limit
Discharged 46.8 mg/L against a permitted limit of 20 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
235% over limit
Discharged 33.45 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
263% over limit
Discharged 5.44 mg/L against a permitted limit of 1.5 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
73% over limit
Discharged 20.75 mg/L against a permitted limit of 12 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
217% over limit
Discharged 9.52 mg/L against a permitted limit of 3 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
11% over limit
Discharged 23.17760781 kg/d against a permitted limit of 20.88399982 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Solids, total suspended
33% over limit
Discharged 32 mg/L against a permitted limit of 24 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
March 31, 2026
Solids, total suspended
64% over limit
Discharged 19.67 mg/L against a permitted limit of 12 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
689% over limit
Discharged 11.83 mg/L against a permitted limit of 1.5 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
133% over limit
Discharged 23.28 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
29% over limit
Discharged 13.48243789 kg/d against a permitted limit of 10.44199991 kg/d (MO AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
44% over limit
Discharged 28.8 mg/L against a permitted limit of 20 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Phosphorus, total [as P]
312% over limit
Discharged 4.12 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
83% over limit
Discharged 44 mg/L against a permitted limit of 24 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
20% over limit
Discharged 25.15250779 kg/d against a permitted limit of 20.88399982 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
510% over limit
Discharged 18.3 mg/L against a permitted limit of 3 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
February 28, 2026
Nitrogen, ammonia total [as N]
382% over limit
Discharged 21.2 mg/L against a permitted limit of 4.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Phosphorus, total [as P]
401% over limit
Discharged 5.01 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
78% over limit
Discharged 17.78 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
38% over limit
Discharged 33 mg/L against a permitted limit of 24 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Solids, total suspended
56% over limit
Discharged 18.75 mg/L against a permitted limit of 12 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
7% over limit
Discharged 21.3 mg/L against a permitted limit of 20 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
396% over limit
Discharged 15.88 mg/L against a permitted limit of 3.2 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
6% over limit
Discharged 32.10824173 kg/d against a permitted limit of 30.41799974 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
January 31, 2026
Solids, total suspended
29% over limit
Discharged 15.5 mg/L against a permitted limit of 12 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
38% over limit
Discharged 33 mg/L against a permitted limit of 24 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
51% over limit
Discharged 4.846 mg/L against a permitted limit of 3.2 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Phosphorus, total [as P]
161% over limit
Discharged 2.608 mg/L against a permitted limit of 1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
166% over limit
Discharged 11.7 mg/L against a permitted limit of 4.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (3 months ago)
Last confirmed
August 1, 2026 (4 days ago)