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UPDATED: Unhealthy Air Quality in Liberty-Clairton Underscores Need for Stricter Regs, Proactive Com

Updated: Sep 14, 2022

UPDATE: Allegheny County Health Department’s Air Quality Program Monday evening issued this air quality update through the county’s Allegheny Alert system:

Preliminary data recorded on Sunday at the Liberty monitor showed a 24-hour PM2.5 average of 36, which is above the EPA 24-hour standard of 35. This data is not verified and will go through EPA’s filter analysis to determine the final average.

If there was a PM2.5 exceedance, it will be addressed via ACHD’s State Implementation Plan (SIP) for attainment.

We are also aware that the Lawrenceville PM2.5 monitor has been generating inaccurate data since Sunday afternoon. We are troubleshooting those issues and will provide an update when this monitor is back to normal operations.

As we have previously advised, the Health Department monitors temperature inversions and is in contact with industries during inversion periods to ensure compliance with existing permit limits. Improving air quality remains a high priority, and we will continue to implement forward-thinking policies and practices designed to reduce pollution and protect public health. – Jim Kelly, Deputy Director of Environmental Health

For a second consecutive day Monday, Allegheny County residents endured some of the worst air quality in the nation according to data maintained at, a U.S. Environmental Protection Agency website that tracks the Air Quality Index (AQI) throughout the United States.

But as is entirely too often the case, the burden of that air pollution was felt most acutely by residents in and near the Mon Valley more than anywhere else in the county.

In fact, only data from the Allegheny County Health Department (ACHD) monitor located in Liberty Borough caused AQI values to push into the red “unhealthy” range on both Sunday and Monday. AQI values in the red indicate that everyone in the area could begin to experience health effects—and that members of sensitive groups (i.e.: folks with respiratory or cardiovascular issues) could experience more serious health effects.

In addition, another pollutant all too familiar to Mon Valley residents – hydrogen sulfide (H2S) – ended the day Sunday at twice the Pennsylvania state air quality standard of 0.005 ppm. H2S levels were so bad Monday morning that the 24-hour average is guaranteed to exceed the standard again today.

For those who are unfamiliar, coke-making is the primary source of H2S in Allegheny County and U.S. Steel’s Clairton Coke Works is not only the largest emitter in the county but the entire state.

“The most recent bouts of bad air quality underscore the need for stricter coke oven regulations,” GASP Executive Director Rachel Filippini said. “We again call on the Allegheny County Health Department to make revising them a top priority. The longer this process is drawn out, the longer people in the Liberty-Clairton area will suffer.”

An additional concern is that the AQI forecast for Sunday published on was for “good” air quality—somewhere near 12 ug/m3—but the 24-hr average pm2.5 at Liberty exceeded 35 ug/m3, a threshold Allegheny County must stay below 98 percent of the time to meet federal air quality standards.

GASP believes this underscores the need for more air monitoring in the area so we can better pinpoint the source(s) of the pollution, better understand meteorological effects on pollution, and ultimately reduce pollution levels in the ambient air. While GASP applauds ACHD’s draft plan to use more than $300,000 from the Clean Air Fund to fund monitoring activities, we remain concerned that the Air Quality Program might have insufficient resources to effectively do its job.

“We have said it before and we want to say it again: Air quality is a crucial public health issue that needs to be of paramount concern not only to the health department, but county council and our chief executive,” Filippini said. “GASP is again calling on Rich Fitzgerald to join residents and environmental groups in calling for better funding for the program. GASP last week called on the department to seek a grant for additional air quality monitoring through an EPA program—a call we are renewing today.”

But more monitors alone won’t resolve the issues.

“Part of ACHD’s role is to help keep local communities informed about these very kinds of public health issues. We encourage the Air Quality Program to arm residents with the information they need to make educated decisions during days where air quality is expected to be poor—even on the weekend and on holidays,” she said.

GASP communicated with ACHD staff last week regarding missing wind data from the Liberty monitor station but ACHD has yet to provide a timeline for restoring that data. In addition, wind data ceased being published at the South Fayette monitor with no public notice and critical hourly pm2.5 data form the Lawrenceville monitor has been erratic over the past few days.

“We wish the health department would be more proactive when it comes to these issues instead of waiting for someone to notice,” Filippini said. “At a time when residents are clamoring for more and better information on air quality issues, proactive communication seems like a no brainer.”

For those who would like to take a deeper dive into the data, we created these graphs. Check them out:

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