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Fourth District Court of Appeal Rejects Use of Mitigated Negative Declaration

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June 10, 2015

On May 7, 2015, California’s Fourth District Court of Appeals published an opinion rejecting the use of a Mitigated Negative Declaration (MND) for a special events permit on the basis of contrary noise and traffic impact testimony from neighbors.

The decision, Keep Our Mountains Quiet v. County of Santa Clara, construes the “fair argument” standard favorably with regard to lay testimony and underscores the risks inherent in pursuing an MND in contentious circumstances.

Lay (and Other) Testimony Under the “Fair Argument” Standard

Much of the Keep Our Mountains Quiet decision concerned the question of whether resident testimony regarding the potential noise and traffic effects of a permit for a previously unauthorized special events use (e.g., weddings) constituted substantial evidence supporting a fair argument that the project would result in significant impacts, thereby requiring an Environmental Impact Report (EIR) instead of an MND.

The court first held that a project’s noise effects can be significant even if they do not exceed local noise standards. The court also read the CEQA Guidelines Appendix G significance thresholds to conclude that a lead agency should consider the increase in ambient noise levels caused by a project as well as the absolute noise levels it generates.

Thus, even if the county could show the special events in question would comply with local, absolute noise standards after mitigation, an EIR could still be required if noise testimony from neighboring residents constituted substantial evidence in support of a fair argument that a significant increase in ambient noise levels may occur.

In this particular instance, the court deemed the noise testimony of a neighboring couple to be substantial evidence in support of a fair argument because they could hear “pounding music” from a wedding held before the permit was issued. The court drew a similar conclusion regarding crowd noise claims. A study indicating noise may have negative effects on wild animals in an adjacent open space preserve also constituted substantial evidence that the project might have a significant impact on biological resources when considered in conjunction with observed noise levels at the property line.

The court held that the record contained substantial evidence in support of a fair argument that the project would result in significant traffic impacts, as well. Neighbors and a hired expert observed that a road providing access to the property was in some places much narrower than normally required, lacked improved shoulders and contained more than 30 blind curves. While the road was well below capacity, the project would more than double traffic during operations. Finally, while Caltrans ultimately concluded the project would not pose a significant traffic or road safety impact, its own safety review revealed an accident history twice that of the statewide average.

Attorney Fees

The last section of the Court of Appeal’s opinion addressed the trial court’s disposition of the petitioner’s attorney fee claim. Consistent with the recent decision in SOURCE v. County of San Bernardino, the opinion further reinforces the principle that the assessment of fees by a lower court will not be overturned in the absence of a clear abuse of discretion. (For a more detailed discussion of the SOURCE decision, see our April 17, 2015 CEQA Update).


Keep Our Mountains Quiet is generous in its interpretation of the “fair argument” standard, so much so that it raises the question of whether it would require an EIR of any construction project in the vicinity of a quiet neighborhood, regardless of whether such noise levels were allowed under local regulations.

A solution may lie in an area where the opinion is weakest, specifically, in its failure to consider what exactly may constitute a “substantial” (and therefore significant) increase in ambient noise or traffic hazards, a determination which CEQA leaves to the lead agency’s discretion when defining thresholds of significance. The opinion does not consider whether hearing “pounding music” exceeded the threshold of significance applied by the county; nor, with regard to potential noise impacts on wild animals, does it observe that the Appendix G thresholds concern special status species only, at the species level. By using their discretion to clearly define significance thresholds (rather than just relying on Appendix G), lead agencies could make it easier for the courts (and all others involved) to see whether an MND is appropriate.

That said, to the extent lead agencies do rely directly on the thresholds suggested in Appendix G of the CEQA guidelines, Keep Our Mountains Quietcorrectly distinguishes between increases in ambient noise levels and compliance with local noise standards, which Appendix G calls out separately.

But perhaps all of this might have been avoided. The facts of the case raise the question of whether the court or any of the parties considered the environmental baseline, which must include unauthorized as well as authorized activities. Here, the baseline appears to have included the same unauthorized activities that the permit triggering CEQA review sought to regulate. This suggests little, if any change to the existing physical environment may have been in play, which in turn suggests an MND may not have been inappropriate after all.

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