UNIONVILLE SOUTH WWTF
NPDES ID: MO0026646
E — SNC: Effluent violation (monthly average limit)
The facility discharged more of a pollutant than its permit allows, based on a monthly average.
Violations
March 31, 2026
Nitrogen, ammonia total [as N]
33% over limit
Discharged 13.4 mg/L against a permitted limit of 10.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
396% over limit
Discharged 13.4 mg/L against a permitted limit of 2.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
December 31, 2025
Nitrogen, ammonia total [as N]
61% over limit
Discharged 16.3 mg/L against a permitted limit of 10.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
504% over limit
Discharged 16.3 mg/L against a permitted limit of 2.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
September 30, 2025
E. coli
1074% over limit
Discharged 2419 MPN/100mL against a permitted limit of 206 MPN/100mL (30DA GM)
DMR, Limited - Numeric Violation
E. coli
135% over limit
Discharged 2419 MPN/100mL against a permitted limit of 1030 MPN/100mL (7 DA GEO)
DMR, Limited - Numeric Violation
July 31, 2025
E. coli
125% over limit
Discharged 464 MPN/100mL against a permitted limit of 206 MPN/100mL (30DA GM)
DMR, Limited - Numeric Violation
March 31, 2025
Nitrogen, ammonia total [as N]
162% over limit
Discharged 7.07 mg/L against a permitted limit of 2.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
February 28, 2025
Nitrogen, ammonia total [as N]
41% over limit
Discharged 14.2 mg/L against a permitted limit of 10.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
426% over limit
Discharged 14.2 mg/L against a permitted limit of 2.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
December 31, 2024
Nitrogen, Kjeldahl, total [as N]
0% over limit
Discharged 0 mg/L against a permitted limit of 0 mg/L (MO AVG)
DMR, Monitor Only - Overdue
Phosphorus, total [as P]
0% over limit
Discharged 0 mg/L against a permitted limit of 0 mg/L (MO AVG)
DMR, Monitor Only - Overdue
Nitrogen, ammonia total [as N]
0% over limit
Discharged 0 mg/L against a permitted limit of 0 mg/L (DAILY MX)
DMR, Monitor Only - Overdue
Nitrogen, Kjeldahl, total [as N]
0% over limit
Discharged 0 mg/L against a permitted limit of 0 mg/L (DAILY MX)
DMR, Monitor Only - Overdue
Phosphorus, total [as P]
0% over limit
Discharged 0 mg/L against a permitted limit of 0 mg/L (DAILY MX)
DMR, Monitor Only - Overdue
Nitrogen, ammonia total [as N]
0% over limit
Discharged 0 mg/L against a permitted limit of 0 mg/L (MO AVG)
DMR, Monitor Only - Overdue
Nitrogen, ammonia total [as N]
72% over limit
Discharged 4.64 mg/L against a permitted limit of 2.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrite + Nitrate total [as N]
0% over limit
Discharged 0 mg/L against a permitted limit of 0 mg/L (MO AVG)
DMR, Monitor Only - Overdue
Nitrite + Nitrate total [as N]
0% over limit
Discharged 0 mg/L against a permitted limit of 0 mg/L (DAILY MX)
DMR, Monitor Only - Overdue
November 30, 2024
Nitrogen, ammonia total [as N]
223% over limit
Discharged 10 mg/L against a permitted limit of 3.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
September 30, 2024
Phosphorus, total [as P]
0% over limit
Discharged 0 mg/L against a permitted limit of 0 mg/L (MO AVG)
DMR, Monitor Only - Overdue
Nitrogen, ammonia total [as N]
0% over limit
Discharged 0 mg/L against a permitted limit of 0 mg/L (DAILY MX)
DMR, Monitor Only - Overdue
Nitrogen, Kjeldahl, total [as N]
0% over limit
Discharged 0 mg/L against a permitted limit of 0 mg/L (DAILY MX)
DMR, Monitor Only - Overdue
Nitrogen, Kjeldahl, total [as N]
0% over limit
Discharged 0 mg/L against a permitted limit of 0 mg/L (MO AVG)
DMR, Monitor Only - Overdue
Nitrite + Nitrate total [as N]
0% over limit
Discharged 0 mg/L against a permitted limit of 0 mg/L (MO AVG)
DMR, Monitor Only - Overdue
Nitrogen, ammonia total [as N]
0% over limit
Discharged 0 mg/L against a permitted limit of 0 mg/L (MO AVG)
DMR, Monitor Only - Overdue
Nitrite + Nitrate total [as N]
0% over limit
Discharged 0 mg/L against a permitted limit of 0 mg/L (DAILY MX)
DMR, Monitor Only - Overdue
Phosphorus, total [as P]
0% over limit
Discharged 0 mg/L against a permitted limit of 0 mg/L (DAILY MX)
DMR, Monitor Only - Overdue
First flagged
April 14, 2026 (3 months ago)
Last confirmed
July 13, 2026 (24 days ago)