UNITED SCHOOL DISTRICT #304 SOUTH CAMPUS STP
NPDES ID: IL0053651
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
April 30, 2026
Oxygen, dissolved [DO]
10% over limit
Discharged 4.5 mg/L against a permitted limit of 5 mg/L (DAILY MN)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
25% over limit
Discharged 4.5 mg/L against a permitted limit of 6 mg/L (MN WK AV)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
30% over limit
Discharged 13 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
168% over limit
Discharged 3.75 mg/L against a permitted limit of 1.4 mg/L (MO AVG)
DMR, Limited - Numeric Violation
March 31, 2026
Nitrogen, ammonia total [as N]
5% over limit
Discharged 4 mg/L against a permitted limit of 3.8 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
167% over limit
Discharged 4 mg/L against a permitted limit of 1.5 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
30% over limit
Discharged 13 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
58% over limit
Discharged 19 mg/L against a permitted limit of 12 mg/L (MO AVG)
DMR, Limited - Numeric Violation
February 28, 2026
Nitrogen, ammonia total [as N]
47% over limit
Discharged 5 mg/L against a permitted limit of 3.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
52% over limit
Discharged 5 mg/L against a permitted limit of 3.3 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
50% over limit
Discharged 15 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
83% over limit
Discharged 22 mg/L against a permitted limit of 12 mg/L (MO AVG)
DMR, Limited - Numeric Violation
November 30, 2025
Solids, total suspended
50% over limit
Discharged 18 mg/L against a permitted limit of 12 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
67% over limit
Discharged 5.5 mg/L against a permitted limit of 3.3 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
62% over limit
Discharged 5.5 mg/L against a permitted limit of 3.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
October 31, 2025
Solids, total suspended
83% over limit
Discharged 22 mg/L against a permitted limit of 12 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
27% over limit
Discharged 0.454 kg/d against a permitted limit of 0.35866 kg/d (WKLY AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
79% over limit
Discharged 2.5 mg/L against a permitted limit of 1.4 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
30% over limit
Discharged 13 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
September 30, 2025
Oxygen, dissolved [DO]
7% over limit
Discharged 5.1 mg/L against a permitted limit of 5.5 mg/L (MO AV MN)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
15% over limit
Discharged 11.5 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
May 31, 2025
Nitrogen, ammonia total [as N]
257% over limit
Discharged 5 mg/L against a permitted limit of 1.4 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
32% over limit
Discharged 5 mg/L against a permitted limit of 3.8 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
39% over limit
Discharged 13.9 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
42% over limit
Discharged 2.9 mg/L against a permitted limit of 5 mg/L (DAILY MN)
DMR, Limited - Numeric Violation
Solids, total suspended
75% over limit
Discharged 21 mg/L against a permitted limit of 12 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
52% over limit
Discharged 2.9 mg/L against a permitted limit of 6 mg/L (MN WK AV)
DMR, Limited - Numeric Violation
April 30, 2025
Nitrogen, ammonia total [as N]
329% over limit
Discharged 6 mg/L against a permitted limit of 1.4 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
30% over limit
Discharged 4.2 mg/L against a permitted limit of 6 mg/L (MN WK AV)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
58% over limit
Discharged 6 mg/L against a permitted limit of 3.8 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
16% over limit
Discharged 4.2 mg/L against a permitted limit of 5 mg/L (DAILY MN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
11% over limit
Discharged 6 mg/L against a permitted limit of 5.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
March 31, 2025
Nitrogen, ammonia total [as N]
500% over limit
Discharged 9 mg/L against a permitted limit of 1.5 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
28% over limit
Discharged 3.6 mg/L against a permitted limit of 5 mg/L (DAILY MN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
58% over limit
Discharged 9 mg/L against a permitted limit of 5.7 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
26% over limit
Discharged 25.2 mg/L against a permitted limit of 20 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Solids, total suspended
117% over limit
Discharged 26 mg/L against a permitted limit of 12 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
152% over limit
Discharged 25.2 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
19% over limit
Discharged 0.16798 kg/d against a permitted limit of 0.14074 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
40% over limit
Discharged 3.6 mg/L against a permitted limit of 6 mg/L (MN WK AV)
DMR, Limited - Numeric Violation
Solids, total suspended
8% over limit
Discharged 26 mg/L against a permitted limit of 24 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
137% over limit
Discharged 9 mg/L against a permitted limit of 3.8 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
February 28, 2025
Nitrogen, ammonia total [as N]
103% over limit
Discharged 0.63559999 kg/d against a permitted limit of 0.31326 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
930% over limit
Discharged 34 mg/L against a permitted limit of 3.3 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
97% over limit
Discharged 0.63559999 kg/d against a permitted limit of 0.32234 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
25% over limit
Discharged 25 mg/L against a permitted limit of 20 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Solids, total suspended
25% over limit
Discharged 15 mg/L against a permitted limit of 12 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
150% over limit
Discharged 25 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
900% over limit
Discharged 34 mg/L against a permitted limit of 3.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
January 31, 2025
BOD, carbonaceous [5 day, 20 C]
86% over limit
Discharged 18.6 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
929% over limit
Discharged 35 mg/L against a permitted limit of 3.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
97% over limit
Discharged 0.63559999 kg/d against a permitted limit of 0.32234 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
103% over limit
Discharged 0.63559999 kg/d against a permitted limit of 0.31326 kg/d (MO AVG)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
11% over limit
Discharged 4.9 mg/L against a permitted limit of 5.5 mg/L (MO AV MN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
961% over limit
Discharged 35 mg/L against a permitted limit of 3.3 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, total suspended
8% over limit
Discharged 13 mg/L against a permitted limit of 12 mg/L (MO AVG)
DMR, Limited - Numeric Violation
December 31, 2024
Solids, total suspended
4% over limit
Discharged 25 mg/L against a permitted limit of 24 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Solids, total suspended
108% over limit
Discharged 25 mg/L against a permitted limit of 12 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
7% over limit
Discharged 21.4 mg/L against a permitted limit of 20 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
279% over limit
Discharged 12.5 mg/L against a permitted limit of 3.3 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
114% over limit
Discharged 21.4 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
268% over limit
Discharged 12.5 mg/L against a permitted limit of 3.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
November 30, 2024
Nitrogen, ammonia total [as N]
44% over limit
Discharged 4.75 mg/L against a permitted limit of 3.3 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
40% over limit
Discharged 4.75 mg/L against a permitted limit of 3.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Solids, total suspended
29% over limit
Discharged 15.5 mg/L against a permitted limit of 12 mg/L (MO AVG)
DMR, Limited - Numeric Violation
October 31, 2024
Nitrogen, ammonia total [as N]
71% over limit
Discharged 6.5 mg/L against a permitted limit of 3.8 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
2% over limit
Discharged 5.4 mg/L against a permitted limit of 5.5 mg/L (MO AV MN)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
40% over limit
Discharged 14 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
2355% over limit
Discharged 12.2579999 kg/d against a permitted limit of 0.4994 kg/d (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
20% over limit
Discharged 6.5 mg/L against a permitted limit of 5.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Solids, total suspended
67% over limit
Discharged 20 mg/L against a permitted limit of 12 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
364% over limit
Discharged 6.5 mg/L against a permitted limit of 1.4 mg/L (MO AVG)
DMR, Limited - Numeric Violation
September 30, 2024
Oxygen, dissolved [DO]
31% over limit
Discharged 3.8 mg/L against a permitted limit of 5.5 mg/L (MO AV MN)
DMR, Limited - Numeric Violation
Oxygen, dissolved [DO]
5% over limit
Discharged 3.8 mg/L against a permitted limit of 4 mg/L (MN WK AV)
DMR, Limited - Numeric Violation
Solids, total suspended
63% over limit
Discharged 19.5 mg/L against a permitted limit of 12 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
364% over limit
Discharged 6.5 mg/L against a permitted limit of 1.4 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
71% over limit
Discharged 6.5 mg/L against a permitted limit of 3.8 mg/L (WKLY AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
20% over limit
Discharged 6.5 mg/L against a permitted limit of 5.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
BOD, carbonaceous [5 day, 20 C]
41% over limit
Discharged 14.1 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (3 months ago)
Last confirmed
July 13, 2026 (23 days ago)