In a published opinion filed in consolidated appeals on September 28, 2018, the Fourth District Court of Appeal (Div. 1) affirmed the trial court’s judgment invalidating San Diego County’s adoption of a 2016 Guidance Document that established a generally applicable threshold of significance for GHG analysis of 4.9 metric tons of CO2e per service population per year.  Golden Door Properties, LLC v. County of San Diego/Sierra Club, LLC v. County of San Diego (2018) 27 Cal.App.5th 892.  The Court held the case was ripe because the 2016 Guidance Document’s GHG “Efficiency Metric” set forth the threshold of significance as generally applicable to project proposals; it held the document violated CEQA because it was not formally adopted by ordinance, rule, resolution or regulation through a public review process, and was not supported by substantial evidence adequately explaining how its service population number derived from statewide data constituted an appropriate GHG metric to use for all projects in unincorporated San Diego County.  (CEQA Guidelines, §§ 15064.7(b), (c); Center for Biological Diversity v. California Department of Fish and Wildlife (2015) 62 Cal.4th 204, 227 (“CBD”).)  The Court also held County’s adoption of the threshold of significance in advance of its required Climate Action Plan (CAP) constituted improper “piecemealing [of] environmental regulations” in violation of the Court’s earlier decision and the trial court’s second supplemental writ in the same litigation, which treated the CAP and thresholds of significance based on it as a single CEQA project and required completion of the CAP prior to the adoption of the thresholds of significance.

While decided in the context of continuing and procedurally complex litigation against the County based on its efforts to conduct adequate GHG analysis for its 2011 General Plan update, the Court of Appeal’s opinion also sets forth a few helpful reminders of some basic guideposts relevant to CEQA thresholds of significance, both generally and in the GHG context.  Key points and “takeaways” from the published opinion include:

  • The County’s 2011 General Plan update EIR included mitigation measures requiring the County to address GHG emissions by, inter alia, adopting a CAP and developing thresholds of significance based on the CAP. In an earlier stage of the Sierra Club’s litigation, the County’s 2012 CAP and 2013 Guidelines were invalidated, and the trial court ordered the County to design a schedule for adopting a new CAP and new significance guidelines based thereon and retained continuing jurisdiction to enforce its writ.  While separately developing the CAP, but before its completion, the County published the 2016 Guidance Document containing the “Efficiency Metric” threshold of significance; the Sierra Club amended its petition to challenge that action, and Golden Door Properties, LLC also filed a petition and complaint challenging that action, which was ultimately heard with Sierra Club’s challenge and consolidated on County’s appeals.
  • CEQA Guidelines § 15064.4(b), adopted in 2010, gives lead agencies discretion for estimating the amount of a project’s GHG emissions and, per the Court, offers three factors to consider: “(1) the extent to which the project may increase or reduce GHG emissions as compared to the existing environmental setting; (2) whether project emissions exceed a threshold of significance the lead agency deems applicable; and (3) the extent to which the project complies with regulations or requirements implementing a statewide, regional, or local plan to reduce or mitigate GHG emissions.”   Further, to constitute appropriate thresholds of significance, such requirements “must be adopted by the relevant public agency through a public review process and must reduce or mitigate the project’s incremental contribution of greenhouse gas emissions.  If there is substantial evidence that the possible effects of a particular project are still cumulatively considerable notwithstanding compliance with the adopted regulations or requirements, an EIR must be prepared for the project.”  (§ 15064.4(b)(3).)
  • Under the “Significance Determination” section of the County’s 2016 Guidance Document, “the recognized and recommended method” provided for making project GHG impact significance determinations was the “County Efficiency Metric,” which was 4.9 metric tons of CO2e per service population per year for 2020. Like the air district guidelines analyzed in California Building Industry Assn. v. Bay Area Air Quality Management Dist. (2016) 2 Cal.App.5th 1067, the Efficiency Metric provided a generally applicable threshold of significance to be routinely used for making significance determinations, and the facial challenge to it was thus ripe for review.
  • CEQA defines a threshold of significance as “an identifiable, quantitative, qualitative or performance level of a particular environmental effect, non-compliance with which means the effect will normally be determined to be significant by the agency and compliance with which means the effect normally will be determined to be less than significant.” (§ 15064.7(a).)  Per the Court, this definition “do[es] not ask whether the agency normally applies the threshold of significance but instead asks whether the criteria, when applied, normally determines the impact to be significant.”  Under this standard, the 2016 Guidance Document’s “recognized and recommended” Efficiency Metric established the level above which a project’s GHG impact is significant and below which it is not.  Thus, it was not a mere “methodology,” or way to determine a threshold, but an “identifiable and quantitative performance level of the particular environmental effect” normally determining significance, and thus a “threshold of significance.”
  • A threshold of significance for general use (as opposed to a project-specific threshold) “is subject to CEQA public adoption guidelines.” (Citing Save Cuyama Valley v. County of Santa Barbara (2013) 213 Cal.App.4th 1059, 1068.)  The County conceded the 2016 Guidance Document was not formally adopted through a public review process, thus violating “the CEQA requirement that a threshold of significance be adopted “by ordinance, resolution, rule, or regulation, and [be] developed through a public review process.”  (§ 15064.7, subd. (b).)”  (Further, County’s local CEQA Guidelines also required public circulation and review before approval of such administrative guidance.)
  • The 2016 Guidance Document also failed to provide substantial evidence to support its recommended Efficiency Metric, in that it “reli[ed] on statewide data without evidence supporting its relationship to countywide [GHG] reductions[.]”  Holding this approach was legally flawed under the principles set forth in CBD, supra, 62 Cal.4th at 225-227, the Court explained:  “[T]he [Efficiency Metric’s] service population number relies on statewide service population and GHG inventory data; it does not address San Diego County specifically, and it does not explain why using statewide data is appropriate for setting the metric for San Diego County.  Additionally, the Efficiency Metric “allows the threshold to be applied evenly to most project types,” but it does not account for variations between different types of development; nor does it explain why the per person limit would be appropriately evenly applied despite project differences.  Without substantial evidence explaining why statewide GHG reduction levels would be properly used in this context, the County fails to comply with CEQA Guidelines.”


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