GRAY SUMMIT WWTF
NPDES ID: MO0098981
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: 7 effluent violations.
Violations
May 31, 2026
pH
0% over limit
Discharged 10.16 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Numeric Violation
Solids, total suspended
26% over limit
Discharged 101 mg/L against a permitted limit of 80 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, suspended percent removal
57% over limit
Discharged 45 % against a permitted limit of 65 % (MO AV MN)
DMR, Limited - Numeric Violation
April 30, 2026
Oil and grease [soxhlet extr.] tot.
48% over limit
Discharged 14.8 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Numeric Violation
E. coli
143% over limit
Discharged 500 MPN/100mL against a permitted limit of 206 MPN/100mL (30DA GM)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
608% over limit
Discharged 14.86 mg/L against a permitted limit of 2.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
77% over limit
Discharged 14.86 mg/L against a permitted limit of 8.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
March 31, 2026
Solids, total suspended
33% over limit
Discharged 106.7 mg/L against a permitted limit of 80 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
784% over limit
Discharged 23.86 mg/L against a permitted limit of 2.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
BOD, 5-day, percent removal
23% over limit
Discharged 57 % against a permitted limit of 65 % (MO AV MN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
136% over limit
Discharged 23.86 mg/L against a permitted limit of 10.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Solids, suspended percent removal
186% over limit
Discharged 0 % against a permitted limit of 65 % (MO AV MN)
DMR, Limited - Numeric Violation
February 28, 2026
Solids, suspended percent removal
40% over limit
Discharged 51 % against a permitted limit of 65 % (MO AV MN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
185% over limit
Discharged 34.47 mg/L against a permitted limit of 12.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
1012% over limit
Discharged 34.47 mg/L against a permitted limit of 3.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
January 31, 2026
Nitrogen, ammonia total [as N]
1166% over limit
Discharged 39.25 mg/L against a permitted limit of 3.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
224% over limit
Discharged 39.25 mg/L against a permitted limit of 12.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Solids, suspended percent removal
6% over limit
Discharged 63 % against a permitted limit of 65 % (MO AV MN)
DMR, Limited - Numeric Violation
December 31, 2025
Nitrogen, ammonia total [as N]
355% over limit
Discharged 45.97 mg/L against a permitted limit of 10.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
1603% over limit
Discharged 45.97 mg/L against a permitted limit of 2.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
November 30, 2025
Nitrogen, ammonia total [as N]
362% over limit
Discharged 38.77 mg/L against a permitted limit of 8.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
1515% over limit
Discharged 38.77 mg/L against a permitted limit of 2.4 mg/L (MO AVG)
DMR, Limited - Numeric Violation
October 31, 2025
E. coli
1550% over limit
Discharged 3400 MPN/100mL against a permitted limit of 206 MPN/100mL (30DA GM)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
358% over limit
Discharged 38.43 mg/L against a permitted limit of 8.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
E. coli
230% over limit
Discharged 3400 MPN/100mL against a permitted limit of 1030 MPN/100mL (7 DA GEO)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
2035% over limit
Discharged 38.43 mg/L against a permitted limit of 1.8 mg/L (MO AVG)
DMR, Limited - Numeric Violation
September 30, 2025
Nitrogen, ammonia total [as N]
1634% over limit
Discharged 20.81 mg/L against a permitted limit of 1.2 mg/L (MO AVG)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
1634% over limit
Discharged 20.81 mg/L against a permitted limit of 1.2 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Flow, in conduit or thru treatment plant
0% over limit
Discharged 0.1 MGD against a permitted limit of 0 MGD (MO AVG)
DMR, Monitor Only - Overdue
BOD, 5-day, 20 deg. C
0% over limit
Discharged 13 mg/L against a permitted limit of 65 mg/L (WKLY AVG)
DMR, Limited - Overdue
BOD, 5-day, percent removal
0% over limit
Discharged 95 % against a permitted limit of 65 % (MO AV MN)
DMR, Limited - Overdue
E. coli
0% over limit
Discharged 900 MPN/100mL against a permitted limit of 1030 MPN/100mL (7 DA GEO)
DMR, Limited - Overdue
Oil and grease [soxhlet extr.] tot.
0% over limit
Discharged 1 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Overdue
BOD, 5-day, 20 deg. C
0% over limit
Discharged 13 mg/L against a permitted limit of 45 mg/L (MO AVG)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
148% over limit
Discharged 20.81 mg/L against a permitted limit of 8.4 mg/L (DAILY MX)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
148% over limit
Discharged 20.81 mg/L against a permitted limit of 8.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
pH
0% over limit
Discharged 6.82 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Overdue
E. coli
337% over limit
Discharged 900 MPN/100mL against a permitted limit of 206 MPN/100mL (30DA GM)
DMR, Limited - Overdue
E. coli
337% over limit
Discharged 900 MPN/100mL against a permitted limit of 206 MPN/100mL (30DA GM)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
0% over limit
Discharged 237 mg/L against a permitted limit of 0 mg/L (MO AVG)
DMR, Monitor Only - Overdue
Solids, suspended percent removal
0% over limit
Discharged 96 % against a permitted limit of 65 % (MO AV MN)
DMR, Limited - Overdue
Flow, in conduit or thru treatment plant
0% over limit
Discharged 0.01 MGD against a permitted limit of 0 MGD (DAILY MX)
DMR, Monitor Only - Overdue
Oil and grease [soxhlet extr.] tot.
0% over limit
Discharged 1 mg/L against a permitted limit of 15 mg/L (DAILY MX)
DMR, Limited - Overdue
Solids, total suspended
0% over limit
Discharged 270 mg/L against a permitted limit of 0 mg/L (MO AVG)
DMR, Monitor Only - Overdue
Solids, total suspended
0% over limit
Discharged 12 mg/L against a permitted limit of 80 mg/L (MO AVG)
DMR, Limited - Overdue
Solids, total suspended
0% over limit
Discharged 12 mg/L against a permitted limit of 120 mg/L (WKLY AVG)
DMR, Limited - Overdue
pH
0% over limit
Discharged 6.82 SU against a permitted limit of 6.5 SU (MINIMUM)
DMR, Limited - Overdue
August 31, 2025
E. coli
240% over limit
Discharged 700 MPN/100mL against a permitted limit of 206 MPN/100mL (30DA GM)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
5413% over limit
Discharged 49.62 mg/L against a permitted limit of 0.9 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
491% over limit
Discharged 49.62 mg/L against a permitted limit of 8.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
July 31, 2025
E. coli
3589% over limit
Discharged 7600 MPN/100mL against a permitted limit of 206 MPN/100mL (30DA GM)
DMR, Limited - Overdue
E. coli
3589% over limit
Discharged 7600 MPN/100mL against a permitted limit of 206 MPN/100mL (30DA GM)
DMR, Limited - Numeric Violation
Flow, in conduit or thru treatment plant
0% over limit
Discharged 0.01 MGD against a permitted limit of 0 MGD (MO AVG)
DMR, Monitor Only - Overdue
BOD, 5-day, 20 deg. C
0% over limit
Discharged 24 mg/L against a permitted limit of 45 mg/L (MO AVG)
DMR, Limited - Overdue
Solids, suspended percent removal
0% over limit
Discharged 78 % against a permitted limit of 65 % (MO AV MN)
DMR, Limited - Overdue
Solids, total suspended
0% over limit
Discharged 36 mg/L against a permitted limit of 120 mg/L (WKLY AVG)
DMR, Limited - Overdue
Solids, total suspended
0% over limit
Discharged 165 mg/L against a permitted limit of 0 mg/L (MO AVG)
DMR, Monitor Only - Overdue
Oil and grease [soxhlet extr.] tot.
0% over limit
Discharged 1 mg/L against a permitted limit of 10 mg/L (MO AVG)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
204% over limit
Discharged 25.5 mg/L against a permitted limit of 8.4 mg/L (DAILY MX)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
204% over limit
Discharged 25.5 mg/L against a permitted limit of 8.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
pH
0% over limit
Discharged 7.08 SU against a permitted limit of 6.5 SU (MINIMUM)
DMR, Limited - Overdue
Oil and grease [soxhlet extr.] tot.
0% over limit
Discharged 1 mg/L against a permitted limit of 15 mg/L (DAILY MX)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
2733% over limit
Discharged 25.5 mg/L against a permitted limit of 0.9 mg/L (MO AVG)
DMR, Limited - Overdue
Nitrogen, ammonia total [as N]
2733% over limit
Discharged 25.5 mg/L against a permitted limit of 0.9 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Flow, in conduit or thru treatment plant
0% over limit
Discharged 0.01 MGD against a permitted limit of 0 MGD (DAILY MX)
DMR, Monitor Only - Overdue
pH
0% over limit
Discharged 7.08 SU against a permitted limit of 9 SU (MAXIMUM)
DMR, Limited - Overdue
BOD, 5-day, percent removal
0% over limit
Discharged 91 % against a permitted limit of 65 % (MO AV MN)
DMR, Limited - Overdue
E. coli
638% over limit
Discharged 7600 MPN/100mL against a permitted limit of 1030 MPN/100mL (7 DA GEO)
DMR, Limited - Overdue
E. coli
638% over limit
Discharged 7600 MPN/100mL against a permitted limit of 1030 MPN/100mL (7 DA GEO)
DMR, Limited - Numeric Violation
Solids, total suspended
0% over limit
Discharged 36 mg/L against a permitted limit of 80 mg/L (MO AVG)
DMR, Limited - Overdue
BOD, 5-day, 20 deg. C
0% over limit
Discharged 24 mg/L against a permitted limit of 65 mg/L (WKLY AVG)
DMR, Limited - Overdue
BOD, 5-day, 20 deg. C
0% over limit
Discharged 275 mg/L against a permitted limit of 0 mg/L (MO AVG)
DMR, Monitor Only - Overdue
June 30, 2025
Solids, suspended percent removal
186% over limit
Discharged 0 % against a permitted limit of 65 % (MO AV MN)
DMR, Limited - Numeric Violation
E. coli
725% over limit
Discharged 1700 MPN/100mL against a permitted limit of 206 MPN/100mL (30DA GM)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
75% over limit
Discharged 2.28 mg/L against a permitted limit of 1.3 mg/L (MO AVG)
DMR, Limited - Numeric Violation
E. coli
65% over limit
Discharged 1700 MPN/100mL against a permitted limit of 1030 MPN/100mL (7 DA GEO)
DMR, Limited - Numeric Violation
May 31, 2025
Nitrogen, ammonia total [as N]
86% over limit
Discharged 3.9 mg/L against a permitted limit of 2.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
E. coli
182% over limit
Discharged 2900 MPN/100mL against a permitted limit of 1030 MPN/100mL (7 DA GEO)
DMR, Limited - Numeric Violation
E. coli
1308% over limit
Discharged 2900 MPN/100mL against a permitted limit of 206 MPN/100mL (30DA GM)
DMR, Limited - Numeric Violation
April 30, 2025
Nitrogen, ammonia total [as N]
590% over limit
Discharged 14.49 mg/L against a permitted limit of 2.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
E. coli
152% over limit
Discharged 2600 MPN/100mL against a permitted limit of 1030 MPN/100mL (7 DA GEO)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
73% over limit
Discharged 14.49 mg/L against a permitted limit of 8.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Solids, suspended percent removal
106% over limit
Discharged 28 % against a permitted limit of 65 % (MO AV MN)
DMR, Limited - Numeric Violation
E. coli
1162% over limit
Discharged 2600 MPN/100mL against a permitted limit of 206 MPN/100mL (30DA GM)
DMR, Limited - Numeric Violation
March 31, 2025
Nitrogen, ammonia total [as N]
411% over limit
Discharged 13.81 mg/L against a permitted limit of 2.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Solids, suspended percent removal
126% over limit
Discharged 21 % against a permitted limit of 65 % (MO AV MN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
37% over limit
Discharged 13.81 mg/L against a permitted limit of 10.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
February 28, 2025
Solids, suspended percent removal
103% over limit
Discharged 29 % against a permitted limit of 65 % (MO AV MN)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
105% over limit
Discharged 24.8 mg/L against a permitted limit of 12.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
BOD, 5-day, 20 deg. C
20% over limit
Discharged 54 mg/L against a permitted limit of 45 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
700% over limit
Discharged 24.8 mg/L against a permitted limit of 3.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
January 31, 2025
Nitrogen, ammonia total [as N]
50% over limit
Discharged 18.2 mg/L against a permitted limit of 12.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
487% over limit
Discharged 18.2 mg/L against a permitted limit of 3.1 mg/L (MO AVG)
DMR, Limited - Numeric Violation
December 31, 2024
Nitrogen, ammonia total [as N]
1205% over limit
Discharged 35.23 mg/L against a permitted limit of 2.7 mg/L (MO AVG)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
249% over limit
Discharged 35.23 mg/L against a permitted limit of 10.1 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
November 30, 2024
Nitrogen, ammonia total [as N]
257% over limit
Discharged 29.97 mg/L against a permitted limit of 8.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
1149% over limit
Discharged 29.97 mg/L against a permitted limit of 2.4 mg/L (MO AVG)
DMR, Limited - Numeric Violation
October 31, 2024
E. coli
288% over limit
Discharged 800 MPN/100mL against a permitted limit of 206 MPN/100mL (30DA GM)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
277% over limit
Discharged 31.64 mg/L against a permitted limit of 8.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
1658% over limit
Discharged 31.64 mg/L against a permitted limit of 1.8 mg/L (MO AVG)
DMR, Limited - Numeric Violation
September 30, 2024
Nitrogen, ammonia total [as N]
2007% over limit
Discharged 25.28 mg/L against a permitted limit of 1.2 mg/L (MO AVG)
DMR, Limited - Numeric Violation
E. coli
240% over limit
Discharged 700 MPN/100mL against a permitted limit of 206 MPN/100mL (30DA GM)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
201% over limit
Discharged 25.28 mg/L against a permitted limit of 8.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
August 31, 2024
Nitrogen, ammonia total [as N]
119% over limit
Discharged 18.36 mg/L against a permitted limit of 8.4 mg/L (DAILY MX)
DMR, Limited - Numeric Violation
Nitrogen, ammonia total [as N]
1940% over limit
Discharged 18.36 mg/L against a permitted limit of 0.9 mg/L (MO AVG)
DMR, Limited - Numeric Violation
July 31, 2024
Nitrogen, ammonia total [as N]
556% over limit
Discharged 5.9 mg/L against a permitted limit of 0.9 mg/L (MO AVG)
DMR, Limited - Numeric Violation
E. coli
3201% over limit
Discharged 6800 MPN/100mL against a permitted limit of 206 MPN/100mL (30DA GM)
DMR, Limited - Numeric Violation
E. coli
560% over limit
Discharged 6800 MPN/100mL against a permitted limit of 1030 MPN/100mL (7 DA GEO)
DMR, Limited - Numeric Violation
First flagged
April 14, 2026 (3 months ago)
Last confirmed
July 13, 2026 (23 days ago)