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

On remand from the California Supreme Court, the California Court of Appeal concluded that thresholds of significance based on impacts on a proposed project’s occupants (receptor thresholds) could be used for some purposes in reviews under the California Environmental Quality Act (CEQA), though such thresholds could not be used to require an environmental impact report or mitigation measures based solely on the impacts of the existing environment on a proposed project. (The California Supreme Court held in December 2015 that portions of the statewide CEQA guidelines that required consideration of the impacts of existing conditions were not valid.) The California Court of Appeal considered how the Supreme Court’s decision applied to receptor thresholds established by the Bay Area Air Quality Management District (BAAQMD) for toxic air contaminants and fine particulate matter. (BAAQMD’s receptor thresholds for greenhouse gases were not specifically at issue in this case.) In its August 2016 decision, the appellate court said that permissible uses of the receptor thresholds included voluntary application by lead agencies when considering their own projects and when considering whether a proposed project would exacerbate existing environmental conditions, as well as for school projects and in connection with certain CEQA exemptions for housing developments. The appellate court left open whether the thresholds could be used for determining whether a proposed project is consistent with a general plan.