The case Ione Valley Land, Air, and Water Defense Alliance, LLC v. County of Amador (33 Cal.App.5th 165) was certified for partial publication by the Third District Court of Appeal, and addresses res judicata in the CEQA context.

The controversy originated with the County of Amador certification of an EIR for an aggregate quarry project in 2012. Project opponents, LAWDA, challenged the County’s approval of the project and certification of the EIR. The trial court granted LAWDA’s petition on the single issue of traffic because the EIR did not accurately portray data from a traffic impact study and did not disclose traffic information in an adequate manner. The County issued a partially recirculated draft EIR in 2014, certified the partially recirculated draft EIR, and approved the project. LAWDA again filed a petition for writ of mandate challenging the County’s approval. The petition raised both traffic impact and non-traffic impact challenges.

In the published portion of the opinion, the appellate court agreed with the County that LAWDA’s second petition was barred by res judicata on all grounds except those arising from traffic impacts. The court explained that the non-traffic impact issues were already litigated and resolved, or could have been litigated and resolved. In this case, the trial court denied the first petition on all grounds except for traffic impacts. LAWDA could have appealed the trial court’s ruling but did not. Thus, LAWDA’s attempts to re-open non-traffic impact issues with a second petition were improper.