The Allegheny County Health Department is advising residents of poor air quality as warmer temperatures linger in the region.
Temperature inversions — when warm air traps cold air and pollutants close to the surface, often causing bad smells like sulfur or rotten eggs — have impacted air quality across Allegheny County since Friday, according to a statement from health department Deputy Director of Environmental Health Jim Kelly.
Air quality monitors managed by the health department have detected spikes in particulate matter, with the highest readings measured at the Liberty monitor, which measures air quality in the Mon Valley. The potential for temperature inversions is likely to continue for several days, Kelly said. Temperatures exceeded 50 degrees on Monday.
“We’ve been in contact with U.S. Steel, and there have been no reports of unusual activity,” Kelly said in the statement. “Our inspectors haven’t observed anything out of the ordinary at facilities in the Mon Valley, and all facilities in the Mon Valley are operating within their permit limits. We have and will continue to monitor this closely.”
Air quality during a temperature inversion is likely to be in the unhealthy range, especially for people in sensitive groups, including children, older adults, people with heart disease and people with lung disease, the statement said.
“Our Clairton Plant is operating normally, with no issues to report,” a statement from U.S. Steel said. “Clairton has been operating at a reduced production rate of approximately 9,000 tons per day due to market conditions. Clairton is on pace to set a record for fewest stack exceedances in December.”
The health department also levied an unrelated $10,560 fine against U.S. Steel on Monday, according to a separate health department statement. That fine was connected to an enforcement order issued against U.S. Steel on March 25 for a failed stack test at the Clairton Coke Works in November 2018.
The failed stack test and associated enforcement is not related to spikes in pollution caused by inversions this week. It also is unrelated to a Dec. 24, 2018, fire that knocked out pollution controls at the Clairton Coke Works for several months.
