UNION PACIFIC RAILROAD COMPANY
NPDES ID: AR0001775
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: 2 effluent violations.
Violations
May 31, 2026
Solids, total suspended
155% over limit
Discharged 153 mg/L against a permitted limit of 60 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Solids, total suspended
173% over limit
Discharged 81.75 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
February 28, 2026
pH
0% over limit
Discharged 9.67 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Numeric Violation
Solids, total suspended
47% over limit
Discharged 44 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
January 31, 2026
Solids, total suspended
40% over limit
Discharged 42 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
December 31, 2025
Solids, total suspended
90% over limit
Discharged 57 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
November 30, 2025
Solids, total suspended
230% over limit
Discharged 198 mg/L against a permitted limit of 60 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Solids, total suspended
560% over limit
Discharged 198 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
10% over limit
Discharged 33 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
October 31, 2025
pH
0% over limit
Discharged 9.3 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Numeric Violation
Solids, total suspended
120% over limit
Discharged 66 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
10% over limit
Discharged 66 mg/L against a permitted limit of 60 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
August 31, 2025
pH
0% over limit
Discharged 10.07 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Numeric Violation
July 31, 2025
Solids, total suspended
24% over limit
Discharged 37.3 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
June 30, 2025
pH
0% over limit
Discharged 9.37 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Numeric Violation
pH
0% over limit
Discharged 9.64 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Numeric Violation
May 31, 2025
Solids, total suspended
9% over limit
Discharged 32.83 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
April 30, 2025
pH
0% over limit
Discharged 9.58 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
8% over limit
Discharged 32.4 mg/L against a permitted limit of 30 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
March 31, 2025
pH
0% over limit
Discharged 9.12 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Numeric Violation
August 31, 2024
Oil & Grease
49% over limit
Discharged 14.9 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
July 31, 2024
Solids, total suspended
82% over limit
Discharged 54.7 mg/L against a permitted limit of 30 mg/L (MO AVG)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (3 months ago)
Last confirmed
July 13, 2026 (23 days ago)