MONARCH SKI AREA
NPDES ID: CO0031399
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: 1 effluent violation.
Violations
April 30, 2026
Chloride [as Cl]
50% over limit
Discharged 150 mg/L against a permitted limit of 100 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
March 31, 2026
Nitrogen, inorganic total
914% over limit
Discharged 101.4 mg/L against a permitted limit of 10 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Chloride [as Cl]
70% over limit
Discharged 170 mg/L against a permitted limit of 100 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
February 28, 2026
Chloride [as Cl]
60% over limit
Discharged 160 mg/L against a permitted limit of 100 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
January 31, 2026
Chloride [as Cl]
40% over limit
Discharged 140 mg/L against a permitted limit of 100 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
December 31, 2025
Nitrogen, inorganic total
800% over limit
Discharged 90 mg/L against a permitted limit of 10 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Chloride [as Cl]
40% over limit
Discharged 140 mg/L against a permitted limit of 100 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
June 30, 2025
Nitrogen, inorganic total
688% over limit
Discharged 78.8 mg/L against a permitted limit of 10 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
April 30, 2025
Chloride [as Cl]
35% over limit
Discharged 135 mg/L against a permitted limit of 100 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
March 31, 2025
Chloride [as Cl]
76% over limit
Discharged 175.5 mg/L against a permitted limit of 100 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Nitrogen, inorganic total
1319% over limit
Discharged 141.92 mg/L against a permitted limit of 10 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
February 28, 2025
Chloride [as Cl]
48% over limit
Discharged 147.5 mg/L against a permitted limit of 100 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
January 31, 2025
Plant capacity fact. percent of capacity
0% over limit
Discharged 18 % against a permitted limit of 0 % (30DA AVG)
DMR, Monitor Only - Overdue
Flow, in conduit or thru treatment plant
0% over limit
Discharged 0.0075 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 0.0041 MGD against a permitted limit of 0 MGD (30DA AVG)
DMR, Monitor Only - Overdue
Flow, in conduit or thru treatment plant
0% over limit
Discharged 0.0041 MGD against a permitted limit of 0.023 MGD (30DA AVG)
DMR, Limited - Overdue
Flow, in conduit or thru treatment plant
0% over limit
Discharged 0.0075 MGD against a permitted limit of 0 MGD (DAILY MX)
DMR, Monitor Only - Overdue
December 31, 2024
BOD, 5-day, 20 deg. C
0% over limit
Discharged 0.77179999 kg/d against a permitted limit of 0 kg/d (MX 7D AV)
DMR, Monitor Only - Overdue
BOD, 5-day, 20 deg. C
0% over limit
Discharged 0.77179999 kg/d against a permitted limit of 0 kg/d (30DA AVG)
DMR, Monitor Only - Overdue
First flagged
April 14, 2026 (3 months ago)
Last confirmed
July 13, 2026 (23 days ago)