Updated: Sep 12
The Group Against Smog and Pollution (GASP) on Wednesday presented verbal testimony at a public hearing regarding Allegheny County’s draft episodic weather regulations. The hearing, which was held online, featured numerous speakers who shared their concerns about the rules and recommendations to make them more protective of public health.
Please note that while the hearing is over, ACHD is accepting comments through 11:59 p.m. tonight, Wednesday, June 9. We have everything you need to know about the regs, sample comment language, and a form that will route them straight to the health department.
Here’s what our staff attorney Ned Mulcahy presented at the hearing:
Good evening. My name is Ned Mulcahy and I am speaking on behalf of Group Against Smog and Pollution.
Later tonight we will be submitting formal written comments on the proposed Mon Valley Air Pollution Episode – along with a copy of this testimony.
In January 2020, ACHD announced it would: “propose a new air quality regulation in 2020 aimed at emission mitigation requirements for industry operating in the county during weather-related pollution episodes.”
Considering all that’s happened between then and now, we want ACHD and the Air Quality Program to know how much GASP appreciates their efforts.
As for the regulation itself, GASP is largely in support of its approach and aims. EPA’s first air pollution episode regulations were published in 1971. A guidance document published at that time reasoned that: “[s]ince stagnant air masses will prevent dilution of pollutants, the only feasible method for protecting society is to minimize the flow of pollutants from emitters.”
It appears the Pollution Mitigation Plans will accomplish that, but we encourage ACHD to consider amending the rule to spell out more clearly the levels of reductions required.
Two concerns we want to highlight now have to do with the “Mon Valley PM2.5 threshold level.” There is no clear basis for requiring that pollution reduction measures only begin if or after the 24-hour NAAQS level is exceeded.
NAAQS revisions since 1999 typically have included revisions to the “break-points” in AQI categories. But that is at least partially for simplicity and consistency in messaging. In the 2015 Federal Register notice addressing the revised ozone NAAQS, the EPA cautioned against using the AQI category “break-points” as a guide for making policy decisions on controlling emission sources when poor air quality is likely to occur. EPA said: “State, local and tribal agencies should consider whether non-voluntary emissions or activity curtailments are necessary (as opposed to a suite of voluntary measures) for days when the AQI is forecasted to be on the lower end of the moderate category.” Regarding pm2.5, the “moderate” AQI range corresponds to concentrations of 12.1 – 35.4 ug/m3. Even if ACHD sticks with the 35.5 ug/m3 threshold level, ACHD must consider an additional threshold level for shorter-term, high levels of PM2.5.
In its 2019 review of the particulate matter NAAQS, EPA documentation showed that there are potential health consequences of exposure to even two hours of PM2.5 at or around 100 ug/m3.
The EPA chose not to alter the NAAQS methodology – essentially —because of its position such exposures would only likely occur in non-attainment areas and already be addressed. As noted above, the NAAQS need not be followed as a guide for the rule. But of greater importance is that on April 24, 2021, pm2.5 at Liberty averaged 100 ug/m3 over three hours (4a to 7a). The 24-hour average on that day was just 32.5 ug/m3 – below the NAAQS level. ACHD’s must act to protect the health, safety, and welfare of all its citizens and examine an approach to addressing this issue even if EPA did not.