Clean Air Act stationary source · ICIS-AIR PA000706410

MARKWEST LIBERTY MIDSTREAM & RESOURCES/JOHNSTON COMP STA, Canonsburg, PA: Clean Air Act compliance record, inspections, violations, penalties

Name: MARKWEST LIBERTY MIDSTREAM & RESOURCES/JOHNSTON COMP STA, ICIS-AIR PA000706410: Clean Air Act stationary source record
Creator: Velarion Records
License: https://www.usa.gov/government-works

OperatingOperating status
Synthetic minor sourceEmissions classification
No Violation IdentifiedCurrent violation status, as filed
15Compliance evaluations since January 1, 2017
0High-priority violations since January 1, 2017
1Formal enforcement actions since January 1, 2017

MARKWEST LIBERTY MIDSTREAM & RESOURCES/JOHNSTON COMP STA, at 210 JOHNSTON HILL RD, Canonsburg in Washington County, Pennsylvania, is an operating synthetic minor 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”. Washington 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 filed	MARKWEST LIBERTY MIDSTREAM & RESOURCES/JOHNSTON COMP STA
ICIS-AIR ID	PA000706410
EPA facility registry ID	110043678730
Operating status	Operating
Emissions classification	Synthetic minor source
Current violation status (ICIS-AIR high-priority violation field)	No Violation Identified
Address	210 JOHNSTON HILL RD, Canonsburg, PA 15317
County	Washington County
In a nonattainment county	Yes (EPA Green Book)
Industry (NAICS)	Oil and gas extraction (NAICS 2111)
SIC code	1311
EPA region	03

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 MARKWEST LIBERTY MIDSTREAM & RESOURCES/JOHNSTON COMP STA 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

15Evaluations since January 1, 2017
3Full compliance evaluations

Date	What EPA recorded	Agency	Programs
April 19, 2026	PCE Off-Site	State	State Implementation Plan for National Primary and Secondary Ambient Air Quality Standards
June 4, 2025	PCE Off-Site	State	State Implementation Plan for National Primary and Secondary Ambient Air Quality Standards
July 2, 2024	FCE On-Site	State	State Implementation Plan for National Primary and Secondary Ambient Air Quality Standards
April 15, 2024	PCE Off-Site	State	State Implementation Plan for National Primary and Secondary Ambient Air Quality Standards
July 5, 2023	PCE Off-Site	State	State Implementation Plan for National Primary and Secondary Ambient Air Quality Standards
June 13, 2022	PCE Off-Site	State	State Implementation Plan for National Primary and Secondary Ambient Air Quality Standards
January 13, 2022	PCE On-Site Monitoring/Sampling	State	State Implementation Plan for National Primary and Secondary Ambient Air Quality Standards
March 29, 2021	PCE Off-Site	State	State Implementation Plan for National Primary and Secondary Ambient Air Quality Standards
December 21, 2020	FCE On-Site	State	State Implementation Plan for National Primary and Secondary Ambient Air Quality Standards
May 26, 2020	PCE Off-Site	State	State Implementation Plan for National Primary and Secondary Ambient Air Quality Standards
April 10, 2020	PCE Off-Site	State	State Implementation Plan for National Primary and Secondary Ambient Air Quality Standards
May 22, 2019	PCE Off-Site	State	State Implementation Plan for National Primary and Secondary Ambient Air Quality Standards
September 18, 2018	FCE On-Site	State	State Implementation Plan for National Primary and Secondary Ambient Air Quality Standards
March 29, 2018	PCE Off-Site	State	State Implementation Plan for National Primary and Secondary Ambient Air Quality Standards
March 10, 2017	PCE Off-Site	State	State Implementation Plan for National Primary and Secondary Ambient Air Quality Standards

Violations

0Violation determinations since January 1, 2017
0Of them high-priority

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 PA000706410 since January 1, 2017.

Enforcement and penalties

1 formal enforcement actions since January 1, 2017, 1 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.

Date	What EPA recorded	Agency	Penalty, as filed
July 9, 2018	Civil Judicial Action	U.S. EPA	$385,000

Informal enforcement

EPA’s informal action file holds no notice or warning for ICIS-AIR PA000706410 since January 1, 2017.

Stack tests

13Stack tests since January 1, 2017
0Recorded as failed

Date	What EPA recorded	Agency
July 13, 2026	Pass	State
July 15, 2025	Pass	State
July 16, 2024	Pass	State
July 18, 2023	Pass	State
September 8, 2022	Pass	State
August 12, 2022	Pass	State
October 21, 2021	Pass	State
August 23, 2021	Pass	State
August 28, 2020	Pass	State
August 18, 2020	Pass	State
August 22, 2019	Pass	State
August 23, 2018	Pass	State
August 24, 2017	Pass	State

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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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 110043678730 there.

Nearby on the register

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

This page of the Velarion Records public-records register covers the Clean Air Act stationary source record for MARKWEST LIBERTY MIDSTREAM & RESOURCES/JOHNSTON COMP STA in Canonsburg, PA, on EPA's ICIS-AIR register under ID PA000706410. It lists Operating operating status, Synthetic minor source emissions classification, No Violation Identified current violation status, 15 Compliance evaluations since January 1, 2017, 0 High-priority violations since January 1, 2017, and 1 Formal enforcement actions since January 1, 2017. The page also names the program type Clean Air Act stationary source and gives EPA facility registry ID 110043678730.