Allegheny County is increasing air quality monitoring after an explosion at a U.S. Steel plant south of Pittsburgh killed two ...

Regulators are temporarily stepping up pollution monitoring in the Mon Valley after a deadly explosion at U.S. Steel’s ...

U.S. Steel Clairton Coke Works' current limited coke-making capacity due to Monday's explosion is prompting concerns.

The Allegheny County Health Department announced that Mobile Air Units will be deployed in the Mon Valley Thursday and Friday ...

Neighbors of U.S. Steel's Clairton Coke Works and the plants' workers react to the explosion at the plant on Monday that ...

Workers were heating coal and preparing for routine maintenance when an explosion rocked a U.S. Steel plant outside ...

The health department began deploying mobile air units Thursday provided by Pennsylvania’s Department of Environmental ...

Allegheny County Executive Sara Innamorato joined ABC News Live with an update on the investigation of the explosion at a ...