The Environmental Protection Agency and Allegheny County Health Department claim in a federal lawsuit that ATI Allegheny Ludlum and Harsco Corporation are violating the Clean Air Act at a Natrona facility that produces silicon steel from scrap steel.

The lawsuit said that the companies dump the slag from the steel production process on the ground at the River Road facility.

The government agencies say in their complaint that "The dumping process, along with knocking solidified slag off the ladle, generates significant fugitive emissions into the air."

(Sourced from Pittsburgh Tribune)