Responsible Development for Water Tank Hill v. County of San Mateo

The California Court of Appeal affirmed the rejection of California Environmental Quality Act and other claims challenging the County of San Mateo’s approval of a 19-home residential development. The organization challenging the project argued unsuccessfully that the County used flawed methodology to determine that greenhouse gas emissions during construction could be mitigated to a less than significant level. The environmental impact report’s (EIR’s) analysis concluded that there would be a less-than-significant cumulative impact on greenhouse gas emissions if mitigation measures were required to reduce project-related emissions by 26% below business-as-usual, to match the statewide goal for greenhouse gas emissions reductions. The Court of Appeal said this assumption did not suffer from the same flaws as the analysis struck down by the California Supreme Court in Center for Biological Diversity v. Department of Fish & Wildlife, which found insufficient evidence to support a conclusion that reducing business-as-usual emissions at the project level was consistent with achieving statewide goals. In an unpublished opinion, the Court of Appeal distinguished the instant case as involving “analysis of GHG emissions during a finite construction phase of the project” while the Center for Biological Diversity case involved “the impact of GHG emissions resulting from the operation of a massive development project.” The Court of Appeal also noted that in this case the EIR assumed that construction emissions would be significant and an “objective concrete method” to reduce emissions was required, whereas the agency in Center for Biological Diversity concluded no greenhouse gas mitigation measures were required because impacts would not be significant.