Clean Water Act discharge permit · NPDES MTG310042

SOMONT OIL CO INC WOODS TANK BATTERY, Oilmont, MT: NPDES MTG310042 discharge permit, effluent exceedances, inspections, penalties

Administratively continuedPermit status
MinorDischarger class
5Pollutants under a numeric limit
1Pollutants with an effluent exceedance

SOMONT OIL CO INC WOODS TANK BATTERY, held by SOMONT OIL COMPANY INC, holds NPDES permit MTG310042, which discharges to Ephemeral Drainage. EPA’s file records it issued May 1, 2015 and expiring April 30, 2020. 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 filed	SOMONT OIL CO INC WOODS TANK BATTERY
Permittee as filed	SOMONT OIL COMPANY INC
NPDES ID	MTG310042
Permit status	Administratively continued (past its expiration date and still in force until reissued)
Permit type	Coverage under a general permit
Discharger class	Minor discharger
Facility type	Not a publicly owned treatment works
Issued	May 1, 2015
Expiration date	April 30, 2020
Address	Oilmont, MT 59466
Receiving water	EPHEMERAL DRAINAGE
Subwatershed	Fifteenmile Coulee (HUC 100302040101)
SIC	1311 – Crude Petroleum And Natural Gas

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

6Pollutants on file
5Under a numeric limit
6With a violation of any kind
1With an effluent exceedance

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 measure	Limits	Violations, any kind	Effluent exceedances	Latest exceedance	Largest exceedance, as filed
Solids, total dissolved [TDS]	1	3	1	December 31, 2010	266% over the limit
Conductivity	2	6	0
Sulfate, total [as SO4]	2	6	0
Flow rate	1	2	0
Oil and grease, hexane extr method	1	2	0
Fluoride	0	1	0

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

3Single-event violations

Date	What EPA recorded	Agency
November 7, 2024	Management Practice Violations - Failure to Maintain Records	ST6
November 7, 2024	Reporting Violations - Improper/ Incorrect Reporting	ST6
April 4, 2019	Reporting Violations - Improper/ Incorrect Reporting	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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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 MTG310042 there.

Nearby on the register

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

This public-records page covers NPDES permit MTG310042, held by SOMONT OIL COMPANY INC for the SOMONT OIL CO INC WOODS TANK BATTERY in Oilmont, MT, which discharges to Ephemeral Drainage in the Fifteenmile Coulee subwatershed (HUC 100302040101). The permit is listed as administratively continued, with a Minor Discharger class of 5, 1 pollutant under a numeric limit, and 1 pollutant with an effluent exceedance.