DOON CITY OF STP
NPDES ID: IA0023736
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: 5 effluent violations.
Violations
May 31, 2026
Chloride [as Cl]
7% over limit
Discharged 1172.25704615 kg/d against a permitted limit of 1094.13999081 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Chloride [as Cl]
14% over limit
Discharged 1172.25704615 kg/d against a permitted limit of 1025.13199139 kg/d (30DA AVG)
DMR, Limited - Numeric Violation
Chloride [as Cl]
83% over limit
Discharged 1200 mg/L against a permitted limit of 657 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Chloride [as Cl]
95% over limit
Discharged 1200 mg/L against a permitted limit of 615 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
E. coli
2% over limit
Discharged 240 MPN/100mL against a permitted limit of 235 MPN/100mL (GEO MEAN)
DMR, Limited - Numeric Violation
December 31, 2025
Chloride [as Cl]
15% over limit
Discharged 1257.82878143 kg/d against a permitted limit of 1094.13999081 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Chloride [as Cl]
79% over limit
Discharged 1100 mg/L against a permitted limit of 615 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Chloride [as Cl]
67% over limit
Discharged 1100 mg/L against a permitted limit of 657 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Chloride [as Cl]
23% over limit
Discharged 1257.82878143 kg/d against a permitted limit of 1025.13199139 kg/d (30DA AVG)
DMR, Limited - Numeric Violation
November 30, 2025
Chloride [as Cl]
13% over limit
Discharged 1232.83880564 kg/d against a permitted limit of 1094.13999081 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
pH
0% over limit
Discharged 6.2 SU against a permitted limit of 6.3 SU (DAILY MN)
DMR, Limited - Numeric Violation
Chloride [as Cl]
79% over limit
Discharged 1100 mg/L against a permitted limit of 615 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Chloride [as Cl]
67% over limit
Discharged 1100 mg/L against a permitted limit of 657 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Chloride [as Cl]
20% over limit
Discharged 1232.83880564 kg/d against a permitted limit of 1025.13199139 kg/d (30DA AVG)
DMR, Limited - Numeric Violation
E. coli
138% over limit
Discharged 560 MPN/100mL against a permitted limit of 235 MPN/100mL (GEO MEAN)
DMR, Limited - Numeric Violation
June 30, 2025
E. coli
0% over limit
Discharged 0 MPN/100mL against a permitted limit of 235 MPN/100mL (GEO MEAN)
DMR, Limited - Overdue
Chloride [as Cl]
0% over limit
Discharged 0 kg/d against a permitted limit of 1094.13999081 kg/d (DAILY MX)
DMR, Limited - Overdue
Chloride [as Cl]
23% over limit
Discharged 810 mg/L against a permitted limit of 657 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Chloride [as Cl]
32% over limit
Discharged 810 mg/L against a permitted limit of 615 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Chloride [as Cl]
0% over limit
Discharged 0 kg/d against a permitted limit of 1025.13199139 kg/d (30DA AVG)
DMR, Limited - Overdue
May 31, 2025
Chloride [as Cl]
3% over limit
Discharged 1058.28761111 kg/d against a permitted limit of 1025.13199139 kg/d (30DA AVG)
DMR, Limited - Numeric Violation
E. coli
0% over limit
Discharged 0 MPN/100mL against a permitted limit of 235 MPN/100mL (GEO MEAN)
DMR, Limited - Overdue
Chloride [as Cl]
31% over limit
Discharged 860 mg/L against a permitted limit of 657 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Chloride [as Cl]
40% over limit
Discharged 860 mg/L against a permitted limit of 615 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (3 months ago)
Last confirmed
July 13, 2026 (23 days ago)