Senators Urge EPA to Rescind Proposed Reconsideration of Standards for Particulate Matter

by Paul Ciampoli
APPA News Director
September 27, 2023

A group of Republican senators recently sent a letter to Environmental Protection Agency Administrator Michael Regan arguing that EPA should rescind its proposed reconsideration of the National Ambient Air Quality Standards for particulate matter.

The letter, which was signed by 23 Republican senators, specifically addresses EPA’s proposal to reconsider the PM 2.5 NAAQS and review the NAAQS under the Clean Air Act’s regular five-year review schedule.

EPA Published Proposed Reconsideration of PM NAAQS in January

In January, EPA published a proposed reconsideration of the PM NAAQS. The proposal seeks to lower the primary annual PM 2.5 standard from its current level of 12 micrograms per cubic meter (µg/m3) to within the range of 9-10 µg/m3 and retain the secondary annual PM 2.5 standards, primary and secondary 24-hour PM 2.5 standard, and primary and secondary 24-hour PM-10 standard. 

EPA accepted comments on a lower limit range of 8.0 ug/m3 for the annual PM 2.5 standard. The reconsideration has been controversial because, in December 2020, EPA completed a comprehensive review and published a final decision to retain the 2013 NAAQS for particulate matter PM.

Thirty-three days later, the newly elected Biden administration issued an executive order directing the EPA to review and revise prior agency decisions if appropriate.

EPA also stated it was reconsidering its 2020 decision because the available scientific evidence and technical information indicate that the current standards may not be adequate to protect public health and welfare, as required by the Clean Air Act.

Senators Weigh in

As the PM2.5 standard “is approaching natural background levels, there are fewer sources available to regulate in order to achieve compliance,” the lawmakers said in their Sept. 20 letter. They said that according to the Association of Air Pollution Control Agencies, wildfires and miscellaneous sources accounted for over 70 percent of domestic PM2.5 emissions in 2022.

In addition, the EPA’s policy assessment for the PM NAAQS reconsideration estimated that only 16 percent of PM2.5 emissions come from power plants and industrial sources, “while the vast majority of the emissions are from non-point sources, such as wildfires, construction, road dust, and international transport,” the senators said in their letter.

Many of these non-point sources “are exceedingly onerous or impossible to control, or like wildfires, are beyond the scope of the Clean Air Act’s regulatory authorities. In light of this, sharply lowering the current PM2.5 annual standard would increase nonattainment levels across the country,” the lawmakers said. “This would increase permitting and regulatory burden on manufacturers, energy producers and several other key industries to our economy without a feasible path to attainment given the high costs and diminishing returns of additional control technologies.”

This would result in “Americans inheriting all of the negative consequences of nonattainment: offshoring of our domestic manufacturing, job loss, electric reliability concerns, higher prices, reliance on China, energy insecurity, and slow economic growth,” the letter went on to say.

At the same time, “it would produce little to no measurable public health or environmental benefits,” the senators argued.

This proposal, “particularly with its confounding inclusion of a request for comments on a standard as low as 8 µg/m3 that the EPA attests it is not even considering, is already causing uncertainty in the business community.”

The EPA’s proposal “fails to consider several important factors that will make implementation of a lower annual standard extremely difficult, or in some cases impossible, to no measurable benefits to public health, the environment, or the economy,” the senators said, adding that the EPA “should not finalize a discretionary reconsideration of a PM2.5 NAAQS that is unattainable and will likely lack an accompanying, detailed implementation plan.”

APPA Signs on to Letter to EPA

APPA recently signed on to a letter to Regan that urged the EPA to maintain the current particulate matter standard. 

That letter stated that lowering the standard would “put large swaths of the country in non-attainment and permitting gridlock,” threatening investments and jobs.