Sierra Club v. EPA, No. 20-1121 (D.C. Cir. 2022)
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In 1997, EPA adopted stricter NAAQS for ozone. National Ambient Air Quality Standards for Ozone. The agency later adopted an implementation rule that, among other things, construed the Act’s anti-backsliding provision to apply not only when EPA relaxes a NAAQS but also when it strengthens one. The EPA reasoned that if Congress desired to maintain existing controls when a NAAQS is relaxed, Congress also must have intended to maintain such controls when a NAAQS is strengthened. The D.C. Circuit previously sustained the EPA’s interpretation.
The Sierra Club challenged the EPA’s decisions to lift antibacksliding requirements in Houston and Dallas. The EPA responded that the proper and exclusive venue for the Sierra Club’s challenge is the Fifth Circuit. Thus, the D.C. Circuit transferred the case to the Fifth Circuit.
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