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Case Law Updates on the Environment (CLUE)

Case Law Update Details

Case Title

Sierra Club v. EPA

Case No.

873 F.3d 946


U.S. Court of Appeals - D.C. Circuit


Washington DC




PM Hot-Spot Analysis Guidance

Project Type


Project Description

Several environmental organizations challenged EPA’s 2015 guidance for conducting PM2.5 and PM10 hot-spot analyses for conformity determinations. EPA’s prior hot-spot guidance (issued in 2010) instructed project sponsors to evaluate whether a project’s modeled incremental PM emissions on specified extreme day would cause NAAQS to be exceeded. The new 2015 guidance altered the designation of the extreme days used in the hot-spot analysis calculation, which had the effect of making it less likely that a project would not be in conformity. EPA issued the 2015 guidance without undergoing a notice and comment process.

Case Summary

The plaintiffs alleged that EPA violated the Administrative Procedure Act by issuing the 2015 guidance without notice and comment, and that the guidance violated the Clean Air Act. The court dismissed the case without reaching the merits of the plaintiffs’ arguments. The court held that the plaintiffs lacked standing to challenge the changes to the PM2.5 methodology because they did not demonstrate that they would be harmed by the changes. The court also held that the PM10 methodology was not binding on EPA or project sponsors and, therefore, was not a final action that could be challenged in court.

Key Holdings

Litigation Procedure

Standing.  The court held that the plaintiffs did not have standing to challenge the changes to the PM2.5 methodology because they did not demonstrate any injury as a result of the changes. The plaintiffs argued that the changes could cause some of their members to be exposed to additional air pollution from three highway projects under development (I-70 East in Colorado, South Mountain Freeway in Arizona, and I-710 in California). The court determined that there was no evidence that the methodology change would affect any of those projects. Two of the projects (I-70 and South Mountain Freeway) were not located in a NAAQS nonattainment or maintenance area for PM2.5 and, therefore, were not required to conduct a hot-spot analysis for PM2.5. For the third project (I-710), the plaintiffs did not demonstrate that the new methodology would be used or that the new methodology would make any difference. The Draft EIS for that project was released before a quantitative hot-spot analysis was required. A Supplemental EIS—which was released after the plaintiffs filed this lawsuit—explained that the project sponsors were still developing a methodology for conducting a quantitative PM2.5 hot-spot analysis; it was not shown that the project sponsors would use the methodology in the 2015 guidance. In addition, the court noted that there was no evidence that using the 2015 guidance would lead to a different outcome than if the 2010 guidance were used. Thus, the court concluded, the plaintiffs failed to demonstrate that they or their members would suffer any harm as a result of the new PM2.5 methodology.

Final Agency Action.  The court held that it lacked jurisdiction to hear the plaintiffs’ challenge to the changes to the PM10 methodology because the 2015 guidance was not a final action. Under the Clean Air Act, only “final action” taken by the EPA can be challenged in court. The court explained that the plain language of the guidance—it stated that EPA would consider alternative methods of calculating PM10 design value—indicated that the guidance was a nonbinding recommendation. In addition, the court noted that EPA’s conduct under the 2010 guidance (which contained identical relevant language) indicated that the hot-spot guidance was not binding, because EPA had allowed project sponsors to use a different methodology for PM10 design value calculations. Thus, as a nonbinding document, the 2015 guidance was not an agency action, and the court lacked jurisdiction to hear the plaintiffs’ challenge.

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