By Leslie Z. Walker

For the two years following passage of Assembly Bill 32 (Chapter 488, Statutes 2006), practitioners have wrestled with establishing the level at which a project’s contribution to global climate change is considered to be significant for the purposes of the California Environmental Quality Act (“CEQA”).

The Air Resources Board’s (“ARB”) Preliminary Draft Staff Proposal: Recommended Approaches for Setting Interim Significance Thresholds for Greenhouse Gases under California Environmental Quality Act (“Initial Proposal”), released Friday, October 24, 2008, delivers a little guidance and a ray of hope. The plan suggests that: 1) non-zero thresholds are supportable, meaning not every bit of greenhouse gas emission ("GHG") should be considered significant, and 2) GHG-analysis does not affect CEQA statutory and categorical exemptions which would otherwise apply.

The Governor’s Office of Planning and Research (“OPR”), directed by Senate Bill 97 (Chapter 185, Statutes 2007) to develop guidelines for the mitigation of GHGs, asked the ARB to develop GHG-related thresholds of significance. The Initial Proposal is brief, limited in scope, focusing only on residential, commercial, and industrial projects.


Three types of Residential and Commercial Projects are addressed:

  • Projects covered by statutory and categorical CEQA exemptions;
  • Non-exempt projects falling under programmatic documents; and
  • Non-exempt projects evaluated individually.

Statutory and Categorical Exemptions

ARB staff suggests that CEQA’s categorical and statutory exemption provisions continue to apply because projects described in the sections “appear to be relatively small from a GHG perspective.”

Programmatic Documents

As part of the implementation of AB 32, many, including OPR, have preached the importance of addressing GHGs in program level documents. The Initial Proposal reiterates this position, suggesting what a programmatic document must contain with respect to GHG emissions.

A commercial or residential project that is not exempt under an existing categorical or statutory exemption will be presumed to have a less than significant impact if the project complies with a previously approved plan that:

  1. Addresses GHG emissions;
  2. Satisfies CEQA Guidelines section 15064(h)(3);
  3. Meets a GHG target consistent with statewide emission limits in AB 32, if the plan applies beyond 2020;
  4. Is consistent with the GHG reduction target adopted pursuant to SB 375;
  5. Includes a GHG inventory and mechanisms to regularly monitor and evaluate emissions;
  6. Includes specific, enforceable GHG requirements;
  7. Incorporates mechanism that allow the plan to be revised to meet targets; and
  8. Has a certified final CEQA document.

Project Level Documents

For the immediate future, until we see the pervasive development of regional GHG emission reduction plans, the project-specific analysis is more relevant. A non-exempt project is presumed to have a less than significant impact related to climate change if:

  1. The construction meets an interim ARB performance standard for construction-related emissions; and
  2. The operations: a) meet the California Energy Commission’s Tier II Energy Efficiency goal; b) meet an interim ARB performance standard for water use; c) meet an interim ARB performance standard for waste; and d) meet an interim ARB performance standard for transportation; and
  3. The project will emit no more than a to be established limit for metric tons CO2e per year. Criteria for this level have yet to be aired.


For industrial projects, ARB proposes a combination of quantitative and performance standard thresholds. ARB notes that a change in the combination may be appropriate as regulatory requirements are developed. Non-exempt industrial projects will be presumed to have less than significant impacts related to climate change if:

  1. The construction and transportation emissions for the project, with mitigation, meet interim ARB performance standards for construction and transportation, respectively; and
  2. The project, with mitigation, will emit no more than 7,000 metric tons of CO2e per year from non-transportation related GHG sources which include: a) combustion related components; b) process losses; and c) purchased electricity and water usage and wastewater discharge.

The Initial Proposal is at most a rough framework awaiting the development of actual emission levels. ARB has requested public and stakeholder input in the development of these emission levels and the thresholds in general. This request began with a public hearing on October 27, 2008. To view the presentation from this meeting, click here. Comments on the plan may be submitted and viewed at

Leslie Walker is a associate at Abbott & Kindermann, LLP. For questions relating to this article or any other California land use, real estate, environmental and/or planning issues contact Abbott & Kindermann, LLP at (916) 456-9595.

The information presented in this article should not be construed to be formal legal advice by Abbott & Kindermann, LLP, nor the formation of a lawyer/client relationship. Because of the changing nature of this area of the law and the importance of individual facts, readers are encouraged to seek independent counsel for advice regarding their individual legal issues.