U.S. Steel & Contractor Facing $15,300 Fine Related to Dust Issues at Edgar Thomson Works

Editor’s Note: The Allegheny County Health Department periodically updates its website to include documents related to air quality enforcement actions. As part of our watchdog work, GASP monitors this webpage and reports on the air quality violations posted there. 

Since the docket has not been updated since December 2025, GASP is now filing monthly public records requests to glean more timely information related to ACHD’s enforcement efforts. This is one of the most recent actions received through the Right to Know process.

The Allegheny County Health Department (ACHD) has issued a more than $15,000 civil penalty to U.S. Steel and contractor Evergreen Trucking for air quality violations at the Edgar Thomson Works from earlier this year.

According to the May 1 ACHD enforcement order, inspectors on Jan. 15 witnessed the Evergreen’s vacuum truck discharging heavy emissions at Edgar Thomson with an opacity exceeding 60 percent, which violates the facility’s Title V operating permit. 

The Evergreen crew was actively removing collected material from the hoppers of the plant’s Basic Oxygen Process (BOP) Mixer and Desulfurization Baghouse. Upon noticing the excessive emissions, ACHD and U.S. Steel representatives intervened. The vacuum crew halted operations, shut down the vehicle, and subsequently drove the truck offsite.

A report submitted the following day revealed that Evergreen had deployed a truck that was undergoing maintenance and was not supposed to be in service - the truck’s bag filters had recently been washed in preparation for replacement, causing the residual water to freeze and tear the filters. 

Inspectors further noted that none of the four crew members were monitoring the vehicle’s exhaust during the removal activity. The truck operator remained in the cab while three technicians worked inside the mixer house.

The enforcement order notes that a similar emission event occurred about two years ago involving the same contractor, which resulted in a verbal warning but no formal enforcement action at the time.

ACHD determined that inspections conducted by U.S. Steel and Evergreen were insufficient to ensure the proper functioning of the equipment. 

According to the order, Evergreen has since outlined corrective actions, including the implementation of strict equipment checklists, additional operational documentation, and mandated operator observation requirements to prevent future emissions excursions.

No further information was immediately available.

You can read the entire enforcement order here.