ARMSTRONG WORLD INDUSTRIES, INC. MILLWOOD FACILITY
NPDES ID: WV0116661
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: 4 effluent violations.
Violations
May 31, 2026
Zinc, total recoverable
249% over limit
Discharged 0.157 mg/L against a permitted limit of 0.045 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
52% over limit
Discharged 0.197 mg/L against a permitted limit of 0.13 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
April 30, 2026
Zinc, total recoverable
231% over limit
Discharged 0.149 mg/L against a permitted limit of 0.045 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
38% over limit
Discharged 0.18 mg/L against a permitted limit of 0.13 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
January 31, 2026
Zinc, total recoverable
13% over limit
Discharged 0.051 mg/L against a permitted limit of 0.045 mg/L (MO AVG)
DMR, Limited - Numeric Violation
December 31, 2025
Zinc, total recoverable
13% over limit
Discharged 0.051 mg/L against a permitted limit of 0.045 mg/L (MO AVG)
DMR, Limited - Numeric Violation
August 31, 2025
Zinc, total recoverable
18% over limit
Discharged 0.053 mg/L against a permitted limit of 0.045 mg/L (MO AVG)
DMR, Limited - Numeric Violation
May 31, 2025
Zinc, total recoverable
36% over limit
Discharged 0.061 mg/L against a permitted limit of 0.045 mg/L (MO AVG)
DMR, Limited - Numeric Violation
April 30, 2025
Zinc, total recoverable
115% over limit
Discharged 0.28 mg/L against a permitted limit of 0.13 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Zinc, total recoverable
60% over limit
Discharged 0.072 mg/L against a permitted limit of 0.045 mg/L (MO AVG)
DMR, Limited - Numeric Violation
February 28, 2025
Chlorine, total residual
0% over limit
Discharged 0 mg/L against a permitted limit of 0.028 mg/L (MO AVG)
DMR, Limited - Overdue
Zinc, total recoverable
0% over limit
Discharged 0.0595 mg/L against a permitted limit of 0.069 mg/L (MO AVG)
DMR, Limited - Overdue
Chlorine, total residual
0% over limit
Discharged 0.05 mg/L against a permitted limit of 0.057 mg/L (DAILY MX)
DMR, Limited - Overdue
Iron, total recoverable
0% over limit
Discharged 0.76 mg/L against a permitted limit of 2.58 mg/L (DAILY MX)
DMR, Limited - Overdue
Zinc, total recoverable
0% over limit
Discharged 0.0595 mg/L against a permitted limit of 0.13 mg/L (DAILY MX)
DMR, Limited - Overdue
Aluminum, total recoverable
0% over limit
Discharged 0.08 mg/L against a permitted limit of 0.4 mg/L (MO AVG)
DMR, Limited - Overdue
Temperature, water deg. fahrenheit
0% over limit
Discharged 46.2 deg F against a permitted limit of 0 deg F (MO AVG)
DMR, Monitor Only - Overdue
Chloride [as Cl]
0% over limit
Discharged 301 mg/L against a permitted limit of 1230 mg/L (MO AVG)
DMR, Limited - Overdue
Nitrogen, nitrite total [as N]
0% over limit
Discharged 0.0025 mg/L against a permitted limit of 3 mg/L (DAILY MX)
DMR, Limited - Overdue
Nitrogen, nitrite total [as N]
0% over limit
Discharged 0.0025 mg/L against a permitted limit of 0.86 mg/L (MO AVG)
DMR, Limited - Overdue
pH
0% over limit
Discharged 8.52 SU against a permitted limit of 6 SU (INST MIN)
DMR, Limited - Overdue
Iron, total recoverable
0% over limit
Discharged 0.76 mg/L against a permitted limit of 0.83 mg/L (MO AVG)
DMR, Limited - Overdue
Chloride [as Cl]
0% over limit
Discharged 301 mg/L against a permitted limit of 2533 mg/L (DAILY MX)
DMR, Limited - Overdue
Aluminum, total recoverable
0% over limit
Discharged 0.08 mg/L against a permitted limit of 1.1 mg/L (DAILY MX)
DMR, Limited - Overdue
pH
0% over limit
Discharged 8.52 SU against a permitted limit of 9 SU (INST MAX)
DMR, Limited - Overdue
Temperature, water deg. fahrenheit
0% over limit
Discharged 60.9 deg F against a permitted limit of 67.2 deg F (DAILY MX)
DMR, Limited - Overdue
Flow, in conduit or thru treatment plant
0% over limit
Discharged 0.0005 MGD against a permitted limit of 0 MGD (DAILY MX)
DMR, Monitor Only - Overdue
Flow, in conduit or thru treatment plant
0% over limit
Discharged 0.0003 MGD against a permitted limit of 0 MGD (MO AVG)
DMR, Monitor Only - Overdue
November 30, 2024
Zinc, total recoverable
42% over limit
Discharged 0.098 mg/L against a permitted limit of 0.069 mg/L (MO AVG)
DMR, Limited - Numeric Violation
August 31, 2024
Zinc, total recoverable
75% over limit
Discharged 0.121 mg/L against a permitted limit of 0.069 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Zinc, total recoverable
31% over limit
Discharged 0.17 mg/L against a permitted limit of 0.13 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (4 months ago)
Last confirmed
August 15, 2026 (12 hours ago)