US EPA last week released guidance to reverse a long-held Clean Air Act policy
that enabled the Agency to regulate sources of hazardous air pollutants (HAPs) as “major sources” even if the facility no longer had the potential to emit pollutants above the major source threshold.
The Clean Air Act statute recognizes two categories of air pollution sources: “major sources” and “area sources.” A major source is a facility that has the potential to emit 25 tons or more per year of hazardous air pollutants (or 10 tons per year of one single pollutant).
Area sources, on the other hand, have the potential to emit less than that.
Because they emit more pollution, major
sources face stringent requirements for installation and maintenance of pollution control technology—called Maximum Achievable Control Technology, or MACT, Standards under Section 112 of the Clean Air Act.
Read more about MACT Standards and other Clean Air Act rules in Question of the Week: Hazardous Air Pollutants , Part 61 vs. Part 63.
What Was EPA’s Once-In-Always-In Policy?
Established by a 1995 EPA memo
, “the once-in-always-in” policy held that once a facility was deemed a major source, it remained a major source regardless of whether the facility’s potential to emit changed over time.
This meant that once a facility met the definition of a “major source,” EPA would continue to regulate it as such, even if the facility’s potential to emit was lowered below the 25 ton or 10 ton per year threshold.
In other words, facilities that arguably should have faced less
regulation by the letter-of-the-law were in practice subjected to more stringent standards.
Why Did EPA Eliminate the Once-In-Always-In Policy
EPA now argues that the statutory language of the Clean Air Act plainly lays out the distinction between “major sources” and “area sources.” Nowhere in the law is EPA granted authority to regulate a source of hazardous air pollutants as a major source unless the facility has potential to emit a “major” volume of pollutants.
With the once-in-always-in policy gone, facilities will have more incentive to reduce the amount of air pollution they emit, as industry has argued. A major source that reduces air pollution below the 10 ton or 25 ton per year threshold can now expect to have its regulatory burden reduced accordingly.
Master Your Clean Air Act Responsibilities
EPA recently increased fines for Clean Air Act violations
to $97,229 per day, per violation
civil penalty amount under current EPA rules.
Get up to speed with the latest changes to the Clean Air Act and build the skills to identify and carry out your compliance responsibilities with the new Clean Air Act Regulations.
Interactive and available 24/7, the new online course covers the critical elements of EPA’s many Clean Air Act planning, monitoring, and reporting programs. Keep your facility in compliance, protect your personnel, avoid emergency releases, and control pollution.