A court of appeal has upheld an air district’s EIR for an oil refinery modernization project. Communities for a Better Environment v. South Coast Air Quality Management District, 47 Cal. App. 5th 588 (2020).

The petitioner claimed that to analyze project impacts to air quality, the district should have used a baseline of the refinery’s average existing air pollutant emissions. The EIR instead used a baseline of 98th percentile “near-peak” refinery air pollutant emissions. Applying the rule that a court must uphold an agency’s selection of a baseline for CEQA review if substantial evidence supports that baseline, and rejecting the petitioner’s assertion that the “normal” baseline is an “average” baseline, the court examined the evidence.

The district identified its baseline by examining two years of daily refinery emissions, excluding the worst two percent of days to avoid unrepresentative outliers, and then comparing emissions on the 98th percentile “near-peak” days to the refinery’s peak emission days under the proposed project. The court upheld this approach, holding both that a) the district could reasonably focus on near-peak emission days because those were most relevant to public health and b) the 98th percentile approach matched that used by U.S. EPA for nitrogen dioxide reporting and regulation.

The petitioner also claimed the project would allow the refinery to process heavier crudes than in the past, with environmental impacts the EIR did not address. The court concluded that the EIR consistently and logically explained why the project would not in fact allow this change in the refinery’s crude slate to occur.

The court further ruled that because neither the petitioner nor any other commenter had challenged a particular estimate in the EIR during the CEQA process, the petitioner had forfeited any claim based on that estimate.

Finally, the petitioner argued that the EIR omitted important information: the existing volume of crude oil the refinery processed and its unused capacity. The court held that this information was unnecessary because the project would have no effect on overall refinery throughput.

This case is important for its application of recent case law explaining the leeway – and limits – inherent in a lead agency’s discretion to identify baselines for CEQA review.