DEL NORTE WWTF
NPDES ID: CO0020281
S — SNC: Compliance schedule violation
The facility missed a deadline in its compliance schedule by more than 90 days.
This quarter: 6 effluent violations.
Violations
May 31, 2026
Copper, potentially dissolved
90% over limit
Discharged 0.0059 mg/L against a permitted limit of 0.0031 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
April 30, 2026
Copper, potentially dissolved
126% over limit
Discharged 0.007 mg/L against a permitted limit of 0.0031 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, percent removal
47% over limit
Discharged 78 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
March 31, 2026
Copper, potentially dissolved
100% over limit
Discharged 0.0062 mg/L against a permitted limit of 0.0031 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, percent removal
13% over limit
Discharged 83 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
37% over limit
Discharged 41 mg/L against a permitted limit of 30 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
13% over limit
Discharged 51 mg/L against a permitted limit of 45 mg/L (MX 7D AV)
DMR, Limited - Numeric Violation
February 28, 2026
Copper, potentially dissolved
174% over limit
Discharged 0.0085 mg/L against a permitted limit of 0.0031 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, percent removal
40% over limit
Discharged 79 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
January 31, 2026
Copper, potentially dissolved
135% over limit
Discharged 0.0073 mg/L against a permitted limit of 0.0031 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
10% over limit
Discharged 33 mg/L against a permitted limit of 30 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, percent removal
7% over limit
Discharged 84 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
December 31, 2025
LC50 Static Renewal 48Hr Acute Ceriodaphnia dubia
42% over limit
Discharged 57.55 % against a permitted limit of 100 % (MN VALUE)
DMR, Limited - Numeric Violation
LC50 Static Renewal 96Hr Acute Pimephales promelas
15% over limit
Discharged 85.3 % against a permitted limit of 100 % (MN VALUE)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
19% over limit
Discharged 13.12 mg/L against a permitted limit of 11 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
3% over limit
Discharged 31 mg/L against a permitted limit of 30 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, percent removal
40% over limit
Discharged 79 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
November 30, 2025
Nitrogen, ammonia total [as N]
6% over limit
Discharged 8.91 mg/L against a permitted limit of 8.4 mg/L (ROLL AVG)
DMR, Limited - Numeric Violation
Copper, potentially dissolved
23% over limit
Discharged 0.0038 mg/L against a permitted limit of 0.0031 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, percent removal
13% over limit
Discharged 83 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
October 31, 2025
Copper, potentially dissolved
19% over limit
Discharged 0.0037 mg/L against a permitted limit of 0.0031 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
September 30, 2025
Solids, total suspended
4% over limit
Discharged 78 mg/L against a permitted limit of 75 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
August 31, 2025
Solids, total suspended
53% over limit
Discharged 168 mg/L against a permitted limit of 110 mg/L (MX 7D AV)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
11% over limit
Discharged 33.2 mg/L against a permitted limit of 30 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Cadmium, potentially dissolvd
114% over limit
Discharged 0.0079 mg/L against a permitted limit of 0.0037 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
76% over limit
Discharged 132 mg/L against a permitted limit of 75 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Zinc, potentially dissolved
100% over limit
Discharged 0.0962 mg/L against a permitted limit of 0.048 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Copper, potentially dissolved
103% over limit
Discharged 0.0063 mg/L against a permitted limit of 0.0031 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
9% over limit
Discharged 49 mg/L against a permitted limit of 45 mg/L (MX 7D AV)
DMR, Limited - Numeric Violation
BOD, 5-day, percent removal
93% over limit
Discharged 71 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
July 31, 2025
Cadmium, potentially dissolvd
23% over limit
Discharged 0.0114 mg/L against a permitted limit of 0.0093 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Cadmium, potentially dissolvd
208% over limit
Discharged 0.0114 mg/L against a permitted limit of 0.0037 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Copper, potentially dissolved
432% over limit
Discharged 0.0165 mg/L against a permitted limit of 0.0031 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, percent removal
127% over limit
Discharged 66 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
Solids, total suspended
105% over limit
Discharged 225 mg/L against a permitted limit of 110 mg/L (MX 7D AV)
DMR, Limited - Numeric Violation
Solids, total suspended
163% over limit
Discharged 197 mg/L against a permitted limit of 75 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
67% over limit
Discharged 75 mg/L against a permitted limit of 45 mg/L (MX 7D AV)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
97% over limit
Discharged 59 mg/L against a permitted limit of 30 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
June 30, 2025
BOD, 5-day, percent removal
7% over limit
Discharged 84 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
Cadmium, potentially dissolvd
278% over limit
Discharged 0.014 mg/L against a permitted limit of 0.0037 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Copper, potentially dissolved
245% over limit
Discharged 0.0107 mg/L against a permitted limit of 0.0031 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Cadmium, potentially dissolvd
51% over limit
Discharged 0.014 mg/L against a permitted limit of 0.0093 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
LC50 Static Renewal 48Hr Acute Ceriodaphnia dubia
19% over limit
Discharged 81.31 % against a permitted limit of 100 % (MN VALUE)
DMR, Limited - Numeric Violation
May 31, 2025
pH
0% over limit
Discharged 9.11 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Numeric Violation
Copper, potentially dissolved
139% over limit
Discharged 0.0074 mg/L against a permitted limit of 0.0031 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, percent removal
33% over limit
Discharged 80 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
April 30, 2025
pH
0% over limit
Discharged 9.28 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Numeric Violation
BOD, 5-day, percent removal
127% over limit
Discharged 66 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
Copper, potentially dissolved
200% over limit
Discharged 0.0093 mg/L against a permitted limit of 0.0031 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
March 31, 2025
pH
0% over limit
Discharged 9.44 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Numeric Violation
LC50 Static Renewal 48Hr Acute Ceriodaphnia dubia
Limit violation
Discharged 100 % against a permitted limit of 100 % (MN VALUE)
DMR, Limited - Numeric Violation
Copper, potentially dissolved
400% over limit
Discharged 0.0155 mg/L against a permitted limit of 0.0031 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Cadmium, potentially dissolvd
11% over limit
Discharged 0.0041 mg/L against a permitted limit of 0.0037 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
42% over limit
Discharged 64 mg/L against a permitted limit of 45 mg/L (MX 7D AV)
DMR, Limited - Numeric Violation
BOD, 5-day, percent removal
173% over limit
Discharged 59 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
Solids, total suspended
20% over limit
Discharged 90 mg/L against a permitted limit of 75 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
65% over limit
Discharged 49.5 mg/L against a permitted limit of 30 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
February 28, 2025
BOD, 5-day, 20 deg. C
43% over limit
Discharged 43 mg/L against a permitted limit of 30 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Cadmium, potentially dissolvd
245% over limit
Discharged 0.0321 mg/L against a permitted limit of 0.0093 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
BOD, 5-day, percent removal
93% over limit
Discharged 71 % against a permitted limit of 85 % (MO AV MN)
DMR, Limited - Numeric Violation
Cadmium, potentially dissolvd
768% over limit
Discharged 0.0321 mg/L against a permitted limit of 0.0037 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Copper, potentially dissolved
671% over limit
Discharged 0.0239 mg/L against a permitted limit of 0.0031 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
18% over limit
Discharged 53 mg/L against a permitted limit of 45 mg/L (MX 7D AV)
DMR, Limited - Numeric Violation
January 31, 2025
pH
0% over limit
Discharged 9.12 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Numeric Violation
Cadmium, potentially dissolvd
308% over limit
Discharged 0.0151 mg/L against a permitted limit of 0.0037 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Copper, potentially dissolved
355% over limit
Discharged 0.0141 mg/L against a permitted limit of 0.0031 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Cadmium, potentially dissolvd
62% over limit
Discharged 0.0151 mg/L against a permitted limit of 0.0093 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
December 31, 2024
Copper, potentially dissolved
16% over limit
Discharged 0.0036 mg/L against a permitted limit of 0.0031 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
pH
0% over limit
Discharged 9.07 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Numeric Violation
Cadmium, potentially dissolvd
273% over limit
Discharged 0.0138 mg/L against a permitted limit of 0.0037 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Cadmium, potentially dissolvd
48% over limit
Discharged 0.0138 mg/L against a permitted limit of 0.0093 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
November 30, 2024
Cadmium, potentially dissolvd
46% over limit
Discharged 0.0054 mg/L against a permitted limit of 0.0037 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Copper, potentially dissolved
139% over limit
Discharged 0.0074 mg/L against a permitted limit of 0.0031 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
31% over limit
Discharged 11 mg/L against a permitted limit of 8.4 mg/L (ROLL AVG)
DMR, Limited - Numeric Violation
October 31, 2024
Nitrogen, ammonia total [as N]
20% over limit
Discharged 11.3 mg/L against a permitted limit of 9.4 mg/L (ROLL AVG)
DMR, Limited - Numeric Violation
Cadmium, potentially dissolvd
151% over limit
Discharged 0.0093 mg/L against a permitted limit of 0.0037 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Copper, potentially dissolved
365% over limit
Discharged 0.0144 mg/L against a permitted limit of 0.0031 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
September 30, 2024
LC50 Static Renewal 48Hr Acute Ceriodaphnia dubia
Limit violation
Discharged 100 % against a permitted limit of 100 % (MN VALUE)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
21% over limit
Discharged 11.6 mg/L against a permitted limit of 9.6 mg/L (ROLL AVG)
DMR, Limited - Numeric Violation
Copper, potentially dissolved
126% over limit
Discharged 0.007 mg/L against a permitted limit of 0.0031 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
August 31, 2024
Copper, potentially dissolved
274% over limit
Discharged 0.0116 mg/L against a permitted limit of 0.0031 mg/L (30DA AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
18% over limit
Discharged 11.8 mg/L against a permitted limit of 10 mg/L (ROLL AVG)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (3 months ago)
Last confirmed
August 1, 2026 (4 days ago)