Cities, counties and other agencies approving plans and projects subject to the California Environmental Quality Act may not ignore greenhouse gas emissions and climate change. That's the bottom line contained in a technical advisory issued Thursday by the Governor's Office of Planning and Research (OPR).

Meanwhile, on Friday the California Air Resources Board issued protocols for local governments to follow in quantifying and reducing greenhouse gas emissions from their own activities.

The OPR advisory document says that lead agencies must quantify or estimate greenhouse gas emissions from a project, determine whether those emissions are individually or cumulatively significant, and if so, identify project alternatives or impose mitigation measures. If full mitigation is not feasible, the lead agency must adopt a statement of overriding consideration that explains why further mitigation is infeasible, according to OPR.

The advisory document is important because it eliminates the argument that emission of greenhouse gases (GHG) is too speculative an issue to be addressed in environmental review documents, said Brian Nowicki, California climate policy director for the Center for Biological Diversity (CBD). Nowicki's organization has sued several cities that did not consider GHG emissions while reviewing proposed developments.

"Hearing this come from the administrative branch is helpful," Nowicki said. "I think we will see a change over a very short period of time."

While environmentalists appeared to be thrilled with the OPR advisory, the building industry was not celebrating.

"We won't be able to comment on it until we have had a chance to review it carefully," California Building Industry Association spokesman John Frith said.

The advisory specifies "three basic steps" for CEQA compliance:

1) Identify and quantify GHG emissions.

2) Assess the significance of those emissions.

3) If the impact is significant, identify project alternatives or mitigation measures that will reduce the impact below significant.

On the first point, OPR urges lead agencies to "make a good-faith effort, based on available information" to calculate emissions from a project, including emissions from:

• Traffic
• Energy consumption
• Water usage and
• Construction activities.

An attachment to the OPR advisory directs practitioners to modeling tools that are readily available for calculating emissions.

The question of significance may be the trickiest. The OPR advisory says, "As with any environmental impact, lead agencies must determine what constitutes a significant impact. In the absence of regulatory standards for GHG emissions or other scientific data to clearly define what constitutes a ‘significant impact,' individual lead agencies may undertake a project-by-project analysis consistent with available guidance and current CEQA practice."

Although OPR has asked the California Air Resources Board to recommend methods of setting thresholds of significance, the air board has not yet provided such guidance.

Determining whether a project contributes to cumulative impacts may be even trickier. The OPR advisory says that not every project which emits GHG must be found to contribute to a significant cumulative impact, and says reliance on previously approved plans and mitigation programs may be adequate. Documentation is critical.

On the final point, OPR states that mitigation should vary depending on the project, "but may include alternative project designs or locations that conserve energy and water, measures that reduce vehicle miles traveled by fossil-fueled vehicles, measures that contribute to established regional programmatic mitigation strategies, and measures that sequester carbon."

The advisory also includes a three-page attachment of potential mitigation measures. At the top of the list: "Implement land use strategies to encourage jobs/housing proximity, promote transit-oriented development, and encourage high-density development along transit corridors."

The advisory document is set in the context of AB 32 and SB 97. Approved in 2006, the former bill requires California to reduce GHG emissions to 1990 levels by 2020, and to cut emissions further in future decades. The latter bill, approved in 2007, amended CEQA "to clearly establish that GHG emissions and the effects of GHG emissions are appropriate subjects for CEQA analysis," according to the OPR advisory. Guidelines for mitigating the impact of greenhouse gas emissions, as required by SB 97, are in process at OPR and must by law be adopted by the Resources Agency by January 1, 2010.

The technical advisory on CEQA and climate change is available on the OPR website at: