On Thursday, the Allegheny County Health Department Board members approved an air quality plan for bringing the Liberty-Clairton area into compliance for national standards in terms of the federal clean air act.
The vote was unanimous. The area has been one of the region's worst offenders for poor air quality - because of the Clairton Coke Works factory owned by US Steel. It emits ultra-microscopic particles that are harmful to human health because they can be inhaled deep into the lungs. There isn't an air quality standard for that pollutant.
The plan will go into agreement in 2013. By then the company will have made a number of improvements to the plant, mostly replacing old coke oven batteries with new ones.