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Clean Air Act stationary source · ICIS-AIR MT0000003008700008

COLSTRIP STEAM ELECTRIC STATION, Colstrip, MT: Clean Air Act compliance record, inspections, violations, penalties

COLSTRIP STEAM ELECTRIC STATION, at PO BOX 38, Colstrip in Rosebud County, Montana, is an operating major source of air pollution on EPA’s ICIS-AIR register. EPA’s file records its current violation status (ICIS-AIR’s high-priority violation field) as “No Violation Identified”. Rosebud County is on EPA’s Green Book list of areas that do not meet a national air quality standard. The status and classification are as EPA’s facility file stood when Velarion loaded it (September 14, 2026); EPA’s free Detailed Facility Report on ECHO carries the source’s current standing, quarter by quarter.

Identity

Facility as filedCOLSTRIP STEAM ELECTRIC STATION
ICIS-AIR IDMT0000003008700008
EPA facility registry ID110041982520
Operating statusOperating
Emissions classificationMajor source
Current violation status (ICIS-AIR high-priority violation field)No Violation Identified
AddressPO BOX 38, Colstrip, MT 59323
CountyRosebud County
In a nonattainment countyYes (EPA Green Book)
Industry (NAICS)Utilities (NAICS 2211)
EPA region08

Cited to the EPA ICIS-AIR facility file (ECHO download).

Programs and pollutants

Velarion’s copy of EPA’s ICIS-AIR download does not include its program, pollutant and Title V certification files, so this page does not list the Clean Air Act programs COLSTRIP STEAM ELECTRIC STATION is under or the pollutants it is permitted for. The programs each evaluation and violation below was recorded under are shown with it. EPA’s free Detailed Facility Report lists both.

Compliance evaluations

DateWhat EPA recordedAgencyPrograms
August 10, 2026FCE On-SiteStateAcid Rain Deposition Control (CAA Title IV); MACT Standards (40 CFR Part 63); New Source Performance Standards; Prevention of Significant Deterioration of Air Quality; State Implementation Plan for National Primary and Secondary Ambient Air Quality Standards; Title V Permits
September 18, 2024FCE On-SiteStateNew Source Performance Standards; State Implementation Plan for National Primary and Secondary Ambient Air Quality Standards; Title V Permits
August 2, 2022FCE On-SiteStateAcid Rain Deposition Control (CAA Title IV); New Source Performance Standards; Prevention of Significant Deterioration of Air Quality; State Implementation Plan for National Primary and Secondary Ambient Air Quality Standards; Title V Permits
July 16, 2018FCE On-SiteStateAcid Rain Deposition Control (CAA Title IV); MACT Standards (40 CFR Part 63); New Source Performance Standards; Prevention of Significant Deterioration of Air Quality; State Implementation Plan for National Primary and Secondary Ambient Air Quality Standards; Title V Permits
June 5, 2018FCE On-SiteStateNew Source Performance Standards; State Implementation Plan for National Primary and Secondary Ambient Air Quality Standards; Title V Permits

Violations

A high-priority violation (HPV) is the most serious class of Clean Air Act non-compliance an agency records; a federally reportable violation (FRV) is the next step down. Each row is one determination as EPA’s violation history files it.

EPA’s violation history file holds no violation for ICIS-AIR MT0000003008700008 since January 1, 2017.

Enforcement and penalties

0 formal enforcement actions since January 1, 2017, 0 of them with a penalty filed above zero. Each penalty is shown as EPA’s formal action file states it; “Not stated” means the file gives no figure, and $0 is a disclosed zero.

Informal enforcement

EPA’s informal action file holds no notice or warning for ICIS-AIR MT0000003008700008 since January 1, 2017.

Stack tests

The newest 50 of 204.

DateWhat EPA recordedAgency
May 21, 2026PassState
May 21, 2026PassState
April 9, 2026PassState
April 9, 2026PassState
April 9, 2026PassState
April 9, 2026PassState
April 8, 2026PassState
April 8, 2026PassState
January 29, 2026PassState
December 24, 2025PassState
December 24, 2025PassState
October 24, 2025PassState
October 16, 2025PassState
October 16, 2025PassState
August 7, 2025PassState
August 7, 2025PassState
May 20, 2025PassState
May 20, 2025PassState
May 2, 2025PassState
April 29, 2025PassState
April 29, 2025PassState
April 29, 2025PassState
April 29, 2025PassState
April 10, 2025PassState
April 10, 2025PassState
April 7, 2025PassState
April 7, 2025PassState
October 3, 2024PassState
October 3, 2024PassState
May 13, 2024PassState
May 13, 2024PassState
April 3, 2024PassState
April 3, 2024PassState
March 28, 2024PassState
March 28, 2024PassState
March 28, 2024PassState
March 28, 2024PassState
January 29, 2024PassState
December 26, 2023PassState
December 26, 2023PassState
December 21, 2023PassState
October 31, 2023PassState
October 31, 2023PassState
April 21, 2023PassState
April 21, 2023PassState
March 28, 2023PassState
March 28, 2023PassState
March 28, 2023PassState
March 28, 2023PassState
March 28, 2023PassState

Cited to the EPA ICIS-AIR evaluation, violation, stack test and enforcement files (ECHO download), events dated January 1, 2017 or later as loaded; up to 50 rows of each shown, newest first.

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How we handle your data → Privacy

EPA publishes a free Detailed Facility Report for every source on ECHO: its compliance status quarter by quarter, its evaluations, and its violations, enforcement actions and penalties. EPA also sends free notices of new inspections and enforcement actions through ECHO Notify; enter EPA facility registry ID 110041982520 there.

Nearby on the register

Figures from EPA’s ICIS-AIR download, loaded September 14, 2026.

What this page shows

The page covers the Clean Air Act compliance record for COLSTRIP STEAM ELECTRIC STATION in Colstrip, MT. It lists operating status Operating, emissions classification Major source, current violation status No Violation Identified, 5 Compliance evaluations since January 1, 2017, 0 High-priority violations since January 1, 2017, and 0 Formal enforcement actions since January 1, 2017.