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What You Need to Know About Allegheny Co.’s Draft Episodic Weather Regulations & How to Weigh In

Updated: Mar 28

Editor’s Note: The public comment period for Allegheny County’s draft episodic weather regulations is now closed. Thank you to everyone who took the time to submit comments! We will continue to follow the issue – check back for updates.

A proposed change to Allegheny County’s Air Pollution Control Regulations aims to reduce particulate matter pollution in the Mon Valley during periods of stagnant weather patterns often a factor in poor air quality as well as exceedances of state and federal air quality standards.

The new regulation will require facilities in the defined area that produce more than 6.5 tons of pm2.5 annually and/or more than 10 tons of pm10 annually to create and submit to the Allegheny County Health Department (ACHD) “Mitigation Plans” for periods when poor air quality is forecast. ACHD predicts this will affect 18 facilities in the 32 listed municipalities.

During the “Watch” phase, facilities such as U.S. Steel’s Clairton Coke Works must conduct basic checks to ensure equipment is in good working order but also ensure they have adequate staff to take actions required under the “Warning” phase.

Once a “Warning” is issued, facilities must undertake the actions listed in the mitigation plans they filed with ACHD. The specific actions will be catered to each facility and approved on a case-by-case basis.

Although the bulk of the regulation addresses industrial sources of particulate matter pollution, the proposed change will also ban all wood-burning activities when a Mon Valley Air Pollution Watch or Warning has been issued in the defined municipalities.

The County currently has regulations that cover episodes of poor air quality but they are so outdated they don’t even include actions to reduce levels of pm2.5, a substance the EPA first created an ambient air quality standard for in 1997.

GASP began calling on ACHD to strengthen the county’s episodic weather regulations in December 2019, when a prolonged inversion prevented air pollution from dissipating, resulting in local air quality exceeding the federal air quality standard for fine particulate matter six days in a row. During that same period, the region’s air quality exceeded the Pennsylvania state standard for hydrogen sulfide (H2S) eight days in a row.

“The regulations are a positive step but a few concerns remain,” GASP Executive Director Rachel Filippini said. “Namely, the level of reductions required by the mitigation plans are not spelled out and the Warning phase will only begin after a rolling 24-hour average level of pm2.5 exceeds the federal standard.”

GASP is concerned that no actual reductions in pollution emissions are required during the Watch phase, a period when all signs – and ACHD – are pointing to a period of poor air quality.

“The county has been aware of the woefully outdated regulations for decades – it’s imperative that ACHD get it right,” Filippini said. “Industrial polluters need to be accountable for the emissions they spew during these bad weather events. Residents deserve that much and more.”

We encourage you to let ACHD know what you think about the regulations. 

The full text of the proposed changes, ACHD’s memo supporting the regulation, and instruction for submitting comments are all available online here:

Comments are due June 9.

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