California Building Industry Association v. Bay Area Air Quality Management District

The California Supreme Court ruled that the California Environmental Quality Act (CEQA) does not generally require consideration of the effects of existing environmental conditions on a proposed project’s future users or residents, but that CEQA does mandate analysis of how a project may exacerbate existing environmental hazards. The court said that portions of the CEQA guidelines that required consideration of the impacts of existing conditions were not valid. This decision was made in a case concerning the California Building Industry Association’s (CBIA’s) challenge of thresholds of significance for air pollutants, including greenhouse gases (though the particular issue before the Supreme Court did not concern the greenhouse gas thresholds). CBIA had argued that the thresholds for toxic air contaminants and fine particulate matter unlawfully required evaluation of the environment’s impacts on a given project, potentially limiting urban infill projects. The California Court of Appeal had said that the receptor thresholds had valid application regardless of whether CEQA required analysis of impacts of existing environmental conditions on project users. The Supreme Court said that the Court of Appeal should address CBIA’s arguments in light of this opinion’s elaboration of CEQA’s requirements with respect to existing conditions.