Mon Valley air quality on Wednesday 'unsafe' for sensitive residents

Poor air quality descended on the Mon Valley on Wednesday, as levels of particulate matter and hydrogen sulfide surged and Air Quality Index indicators hit levels that were unsafe for sensitive residents.

The rolling 24-hour Air Quality Index, or AQI, at the Liberty monitor continued to increase throughout the day after starting at 130 at 9 a.m. Wednesday, the Allegheny County Health Department said. An AQI in the 100 to 150 range means that the air quality is “unhealthy for sensitive groups.”

A Code Orange Action Day was declared in the Mon Valley by the state Department of Environmental Protection.

Monitor data showed levels of hydrogen sulfide exceeded Pennsylvania’s 24-hour average standard, according to the Regent Square-based nonprofit Group Against Smog and Pollution.

Hydrogen sulfide is a colorless gas recognizable by its rotten egg odor, and concentrations in the Mon Valley might cause irritation to the eyes, nose or throat, as well as headaches, poor memory, tiredness and balance problems, GASP said.

“We’ve heard from residents complaining of itchy eyes and throats, and telling us that by early morning they had already needed to reach for their rescue inhalers,” GASP Executive Director Patrick Campbell told the Tribune-Review on Wednesday. “It’s truly a shame how often residents in the Liberty-Clairton area are confronted with unhealthy air quality. People are really suffering today.”

The closest industrial polluter to the Liberty monitor is U.S. Steel’s Clairton Coke Works.

Companies most significantly contributing to particulate pollution in the Mon Valley region, such as U.S. Steel, are required to temporarily reduce particulate emissions. Allegheny County’s Mon Valley Episode Rule was designed to reduce particulate levels during prolonged periods of poor air quality.

The alert is especially important for young children, elderly people and anyone with respiratory problems. They should limit outdoor activities, according to state environmental officials.

The DEP’s Action Day targeted Clairton, Glassport, Liberty, Lincoln and Port Vue.

Residents and businesses are asked to reduce fireplace and wood stove use, avoid open burning and avoid using gas-powered mowers.

A DEP spokesperson said that a strong late-night and morning temperature inversion with very light winds can contribute to fine particulate matter levels reaching the Code Orange range.