U.S. Steel secures permit to build $100 million slag recycler
Steel News | 2026-02-24 01:33:06
Slag is currently diverted into one of two open pits and cooled with water before being sent to a landfill, where it may leach contaminants into the soil.
By Paul Ploumis
SEATTLE (Scrap Monster): U.S. Steel announced Monday it secured permission from the Allegheny County Health Department to build a $100 million slag recycler at the Edgar Thomson Works.
A critical air quality permit arrived Friday, U.S. Steel said, allowing the company to start site preparation at the facility straddling Braddock and North Braddock.
Construction is slated to begin this summer and take about a year.
U.S. Steel revealed plans in September to modernize how it processes slag, a byproduct of smelting iron ore, at the Edgar Thomson Works.
The $100 million price tag is just a fraction of the $2.4 billion Nippon Steel committed to upgrades at the Mon Valley Works when it purchased U.S. Steel in June.
The Japanese steelmaker also plans to shut down the hot strip mill at the Irvin Works in West Mifflin and replace it with a new one at Edgar Thomson. Steel finishing will continue at the Irvin plant.
The slag recycler is the first of the Mon Valley projects to earn an installation permit from the health department. U.S. Steel said in November it will seek permits for the hot strip mill in the next several months.
When asked Friday about those permit applications, the company said it did not have an update.
All significant sources of air pollution in Allegheny County must obtain permits to operate, add new facilities or modify existing equipment. The recycler cannot go live without an operating permit.
Slag is currently diverted into one of two open pits and cooled with water before being sent to a landfill, where it may leach contaminants into the soil.
The new process takes the slag and forms it into small pieces that can be sold to other industries. Cement manufacturers are major buyers of slag, using it to make their product easier to work with and more durable.
U.S. Steel also claims the fully enclosed system will reduce emissions of sulfur dioxide and hydrogen sulfide — both harmful to human health — from slag processing by as much as 50%.
Environmental groups say they’re reviewing the permit.
Courtesy: www.triblive.com
