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Clean Water Act discharge permit · NPDES MO0036242

MEXICO WWTP, Mexico, MO: NPDES MO0036242 discharge permit, effluent exceedances, inspections, penalties

MEXICO WWTP, held by City of Mexico, holds NPDES permit MO0036242, which discharges to Tributary To S. Fk. Salt R.. EPA’s file records it issued February 4, 2019 and expiring December 31, 2021. The status and dates are as EPA’s permit file stood when Velarion loaded it (October 14, 2026); EPA’s free Detailed Facility Report on ECHO carries the permit’s current standing.

Identity

Facility as filedMEXICO WWTP
Permittee as filedCity of Mexico
NPDES IDMO0036242
Permit statusEffective
Permit typeIndividual permit
Discharger classMajor discharger
Facility typePublicly owned treatment works
ProgramPublicly owned treatment works
IssuedFebruary 4, 2019
Expiration dateDecember 31, 2021
AddressMexico, MO 65265
Receiving waterTributary to S. Fk. Salt R.
SubwatershedLong Branch-South Fork Salt River (HUC 071100060503)
Program components on fileBiosolids, POTW, Pretreatment
SIC4952 – Sewerage Systems

Cited to the EPA ICIS-NPDES permit file (ECHO download) and EPA’s NAICS/SIC and component files, the same download.

Effluent limits and exceedances

An effluent exceedance is a discharge monitoring report value over the permit’s numeric limit (EPA’s violation code E90). A violation of any kind also counts a report not filed. Each row is EPA’s own count for that pollutant.

Pollutant or measureLimitsViolations, any kindEffluent exceedancesLatest exceedanceLargest exceedance, as filed
Oxygen, dissolved [DO]220455November 30, 201187% over the limit
Nitrogen, ammonia total [as N]1213432June 30, 20261,580% over the limit
BOD, 5-day, 20 deg. C42917January 31, 2014875% over the limit
Solids, total suspended22513March 31, 2014593% over the limit
Copper, total recoverable2726March 31, 2018124% over the limit
E. coli2544October 31, 20161,708% over the limit
Solids, suspended percent removal1262July 31, 2021513% over the limit
Ammonia [as N] + unionized ammonia01471June 30, 201026% over the limit
pH2151June 30, 2020
Oil and grease [soxhlet extr.] tot.21900
Application rate area sprayed01360
Rainfall01340
Flow, gallons/batch01280
Cyanide, free [amenable to chlorination]4660
Zinc, total recoverable2640
Lead, total recoverable2640
Toluene0490
Methylene chloride0490
Methanol, total0490
Ampicillin0360
Cefadroxil0360
Cefdinir0360
Cefprozil0360
Dicloxacillin0360
Cephalexin0350
Amoxicillin0220
Nitrogen, Kjeldahl, total [as N]660
Nitrite + Nitrate total [as N]660
Phosphorus, total [as P]660
Pass/Fail Static 48Hr Acute Ceriodaphnia dubia030
LC50 Static 48Hr Acute Pimephales promelas030
Hardness, total [as CaCO3]220
Flow, in conduit or thru treatment plant220
Selenium, total recoverable200
Thallium, total recoverable200
Cadmium, total recoverable200
Toxicity [acute], Ceriodaphnia dubia100
Toxicity [acute], Pimephales promelas [Fathead Minnow]100
BOD, 5-day, percent removal100

Cited to the EPA ICIS-NPDES limits and effluent violations files (ECHO download); up to 60 rows shown, most exceedances first.

Inspections, violations and enforcement

DateWhat EPA recordedAgency
December 31, 2024Permit Violations - Violation Specified in CommentST6
July 11, 2023Permit Violations - Violation Specified in CommentST6
July 11, 2023Effluent Violations - Numeric effluent violationST6
June 21, 2017Pretreatment - Failure to Develop/Enforce StandardsST6
June 21, 2017Permit Violations - Violation Specified in CommentST6
June 21, 2017Reporting Violations - Improper/ Incorrect ReportingST6
June 21, 2017Effluent Violations - Numeric effluent violationST6
June 21, 2017Reporting Violations - Failure to submit required report (non-DMR non-pretreatment)ST6

Velarion’s copy of EPA’s ICIS-NPDES files does not include the inspections, formal enforcement actions and informal enforcement actions files, so this page shows none of them. EPA’s free Detailed Facility Report on ECHO lists this permit’s inspections, enforcement actions and penalties.

Cited to the EPA ICIS-NPDES violation, inspection and enforcement files (ECHO download); up to 50 rows of each shown, newest first.

Watch this permit

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How we handle your data → Privacy

EPA publishes a free Detailed Facility Report for every permit on ECHO: its compliance status quarter by quarter, its inspections, and its enforcement actions and penalties. EPA also sends free notices of new inspections and enforcement actions through ECHO Notify; enter NPDES ID MO0036242 there.

Nearby on the register

Figures from EPA’s ICIS-NPDES download, loaded October 14, 2026.

What this page shows

The MEXICO WWTP, held by City of Mexico under NPDES permit MO0036242, is listed as Effective and classed as a Major discharger, with program components of Biosolids, POTW and Pretreatment. The page reports 39 pollutants on file, 23 of them under a numeric limit, and 3 with an effluent exceedance.