CALLAO WASTEWATER TREATMENT PLANT
NPDES ID: VA0091421
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]
567% over limit
Discharged 6.2 mg/L against a permitted limit of 0.93 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
Nitrogen, Kjeldahl, total [as N]
71% over limit
Discharged 7.7 mg/L against a permitted limit of 4.5 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
Nitrogen, Kjeldahl, total [as N]
10% over limit
Discharged 1.1 kg/d against a permitted limit of 1 kg/d (WKLY AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
146% over limit
Discharged 1.55 mg/L against a permitted limit of 0.63 mg/L (MO AVG)
DMR, Limited - Numeric Violation
February 28, 2026
Nitrogen, Kjeldahl, total [as N]
280% over limit
Discharged 11.4 mg/L against a permitted limit of 3 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, Kjeldahl, total [as N]
130% over limit
Discharged 2.3 kg/d against a permitted limit of 1 kg/d (WKLY AVG)
DMR, Limited - Numeric Violation
Nitrogen, Kjeldahl, total [as N]
150% over limit
Discharged 1.7 kg/d against a permitted limit of 0.68 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, Kjeldahl, total [as N]
180% over limit
Discharged 12.6 mg/L against a permitted limit of 4.5 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
1181% over limit
Discharged 11.91 mg/L against a permitted limit of 0.93 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
1492% over limit
Discharged 10.03 mg/L against a permitted limit of 0.63 mg/L (MO AVG)
DMR, Limited - Numeric Violation
December 31, 2024
Nitrogen, ammonia total [as N]
99% over limit
Discharged 1.85 mg/L against a permitted limit of 0.93 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
15% over limit
Discharged 0.0947 mg/L against a permitted limit of 0.082 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
15% over limit
Discharged 0.0947 mg/L against a permitted limit of 0.082 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (3 months ago)
Last confirmed
July 13, 2026 (23 days ago)