MOUNTAINBURG, CITY OF - WWTP
NPDES ID: AR0021512
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: 19 effluent violations.
Violations
June 30, 2026
Solids, total suspended
130% over limit
Discharged 69 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Coliform, fecal general
26% over limit
Discharged 2510 MPN/100mL against a permitted limit of 2000 MPN/100mL (7 DA GEO)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
29% over limit
Discharged 7.74 mg/L against a permitted limit of 6 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Coliform, fecal general
132% over limit
Discharged 2323 MPN/100mL against a permitted limit of 1000 MPN/100mL (30DA GEO)
DMR, Limited - Numeric Violation
Solids, total suspended
91% over limit
Discharged 86 mg/L against a permitted limit of 45 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
8% over limit
Discharged 14.65057988 kg/d against a permitted limit of 13.61999989 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
10% over limit
Discharged 9.87 mg/L against a permitted limit of 9 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
May 31, 2026
BOD, carbonaceous [5 day, 20 C]
33% over limit
Discharged 20 mg/L against a permitted limit of 15 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
141% over limit
Discharged 14.46 mg/L against a permitted limit of 6 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
36% over limit
Discharged 61 mg/L against a permitted limit of 45 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
85% over limit
Discharged 55.5 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
62% over limit
Discharged 14.6 mg/L against a permitted limit of 9 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
April 30, 2026
Solids, total suspended
17% over limit
Discharged 15.98533987 kg/d against a permitted limit of 13.61999989 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
89% over limit
Discharged 85 mg/L against a permitted limit of 45 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
134% over limit
Discharged 12.4 mg/L against a permitted limit of 5.3 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
94% over limit
Discharged 10.29 mg/L against a permitted limit of 5.3 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
32% over limit
Discharged 33 mg/L against a permitted limit of 25 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Coliform, fecal general
8% over limit
Discharged 1081 MPN/100mL against a permitted limit of 1000 MPN/100mL (30DA GEO)
DMR, Limited - Numeric Violation
Solids, total suspended
173% over limit
Discharged 82 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
March 31, 2026
Solids, total suspended
75% over limit
Discharged 52.5 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
4% over limit
Discharged 47 mg/L against a permitted limit of 45 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
49% over limit
Discharged 67 mg/L against a permitted limit of 45 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
35% over limit
Discharged 40.5 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
February 28, 2026
Solids, total suspended
2% over limit
Discharged 30.5 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
48% over limit
Discharged 2.1 mg/L against a permitted limit of 4 mg/L (INST MIN)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
40% over limit
Discharged 42 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
9% over limit
Discharged 49 mg/L against a permitted limit of 45 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
January 31, 2026
Solids, total suspended
33% over limit
Discharged 60 mg/L against a permitted limit of 45 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
56% over limit
Discharged 70 mg/L against a permitted limit of 45 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
82% over limit
Discharged 54.5 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
82% over limit
Discharged 54.5 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
December 31, 2025
Solids, total suspended
56% over limit
Discharged 70 mg/L against a permitted limit of 45 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
58% over limit
Discharged 47.5 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
5% over limit
Discharged 31.5 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
November 30, 2025
BOD, 5-day, 20 deg. C
18% over limit
Discharged 53 mg/L against a permitted limit of 45 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
28% over limit
Discharged 38.5 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
18% over limit
Discharged 35.5 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
18% over limit
Discharged 53 mg/L against a permitted limit of 45 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
October 31, 2025
BOD, carbonaceous [5 day, 20 C]
23% over limit
Discharged 18.5 mg/L against a permitted limit of 15 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
32% over limit
Discharged 39.5 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
233% over limit
Discharged 30 mg/L against a permitted limit of 9 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
32% over limit
Discharged 4.1 mg/L against a permitted limit of 6 mg/L (INST MIN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
375% over limit
Discharged 28.5 mg/L against a permitted limit of 6 mg/L (MO AVG)
DMR, Limited - Numeric Violation
September 30, 2025
Nitrogen, ammonia total [as N]
267% over limit
Discharged 33 mg/L against a permitted limit of 9 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
49% over limit
Discharged 67 mg/L against a permitted limit of 45 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
400% over limit
Discharged 30 mg/L against a permitted limit of 6 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
85% over limit
Discharged 55.5 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
August 31, 2025
Nitrogen, ammonia total [as N]
533% over limit
Discharged 38 mg/L against a permitted limit of 6 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
400% over limit
Discharged 45 mg/L against a permitted limit of 9 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
3% over limit
Discharged 5.8 mg/L against a permitted limit of 6 mg/L (INST MIN)
DMR, Limited - Numeric Violation
July 31, 2025
BOD, carbonaceous [5 day, 20 C]
10% over limit
Discharged 16.5 mg/L against a permitted limit of 15 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
20% over limit
Discharged 36 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
25% over limit
Discharged 4.5 mg/L against a permitted limit of 6 mg/L (INST MIN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
211% over limit
Discharged 28 mg/L against a permitted limit of 9 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
300% over limit
Discharged 24 mg/L against a permitted limit of 6 mg/L (MO AVG)
DMR, Limited - Numeric Violation
June 30, 2025
Nitrogen, ammonia total [as N]
25% over limit
Discharged 7.5 mg/L against a permitted limit of 6 mg/L (MO AVG)
DMR, Limited - Numeric Violation
May 31, 2025
Nitrogen, ammonia total [as N]
33% over limit
Discharged 12 mg/L against a permitted limit of 9 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
7% over limit
Discharged 16 mg/L against a permitted limit of 15 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
48% over limit
Discharged 8.85 mg/L against a permitted limit of 6 mg/L (MO AVG)
DMR, Limited - Numeric Violation
April 30, 2025
Nitrogen, ammonia total [as N]
51% over limit
Discharged 8 mg/L against a permitted limit of 5.3 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
2% over limit
Discharged 5.4 mg/L against a permitted limit of 5.3 mg/L (MO AVG)
DMR, Limited - Numeric Violation
December 31, 2024
Solids, total suspended
10% over limit
Discharged 33 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
November 30, 2024
Solids, total suspended
34% over limit
Discharged 40.25 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
7% over limit
Discharged 48 mg/L against a permitted limit of 45 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
October 31, 2024
BOD, carbonaceous [5 day, 20 C]
157% over limit
Discharged 38.5 mg/L against a permitted limit of 15 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
1% over limit
Discharged 6.08 mg/L against a permitted limit of 6 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
8% over limit
Discharged 5.5 mg/L against a permitted limit of 6 mg/L (INST MIN)
DMR, Limited - Numeric Violation
Solids, total suspended
33% over limit
Discharged 40 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
126% over limit
Discharged 52 mg/L against a permitted limit of 23 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
September 30, 2024
Nitrogen, ammonia total [as N]
62% over limit
Discharged 14.55 mg/L against a permitted limit of 9 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
Limit violation
Discharged 25 mg/L against a permitted limit of 23 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
130% over limit
Discharged 13.8 mg/L against a permitted limit of 6 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
7% over limit
Discharged 16 mg/L against a permitted limit of 15 mg/L (MO AVG)
DMR, Limited - Numeric Violation
August 31, 2024
Nitrogen, ammonia total [as N]
477% over limit
Discharged 51.94 mg/L against a permitted limit of 9 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
22% over limit
Discharged 36.5 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
481% over limit
Discharged 34.85 mg/L against a permitted limit of 6 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
31% over limit
Discharged 59 mg/L against a permitted limit of 45 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
17% over limit
Discharged 17.5 mg/L against a permitted limit of 15 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
9% over limit
Discharged 25 mg/L against a permitted limit of 23 mg/L (7 DA AVG)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (4 months ago)
Last confirmed
August 16, 2026 (1 hour ago)