## Facts

- A developer proposed a 40-lot rural residential subdivision in Stilson Canyon near Chico, California.
- The County prepared an environmental impact report (EIR) under CEQA that incorporated a walking archaeological survey by a university staff archaeologist.
- The survey identified multiple archaeological sites, including three within the proposed subdivision, and described their contents and prior disturbances.
- The survey reported the on-site areas might contribute to regional prehistory but stated additional testing would be needed to determine significance because of disturbance.
- The draft EIR stated the project would have a significant effect on cultural resources of local significance.
- After public objections at a board hearing, the county planning commission prepared a supplemental report noting the resources were possibly unique and referred to Indian mounds.
- The county approved the project and supplemental report, requiring the developer to allow a six-month period for archaeological testing in certain areas before full buildout, but did not adopt long-term preservation or avoidance measures or materially change project layout.
- A professional archaeological society sought a writ of mandate to compel the county to revoke approval for alleged CEQA noncompliance; the trial court denied relief.

## Issues

1. Whether CEQA requires a public agency to reject, modify, or halt a project pending additional archaeological testing when the EIR identifies potential adverse impacts on archaeological resources.
2. Whether the county abused its discretion or failed to proceed as required by law by approving the project with only a six-month testing condition and without stronger mitigation or preservation measures.
3. Whether the EIR and supplemental report were legally adequate informational documents regarding archaeological impacts and mitigation alternatives.

## Decision

- The Court of Appeal affirmed the judgment denying the writ of mandate.
- The court held the EIR, as supplemented, was legally adequate under CEQA as an informational document.
- The court held CEQA does not require disapproval of a project, further testing as a precondition to approval, or adoption of particular mitigation measures if the agency’s action is supported by substantial evidence and the environmental consequences are adequately disclosed.

## Legal Principles

- An EIR’s central function is disclosure and analysis of environmental consequences; it does not compel a particular substantive outcome.
- CEQA permits agencies to approve projects with acknowledged adverse impacts after considering them and balancing environmental concerns with economic and social objectives.
- Judicial review under Public Resources Code § 21168.5 is limited to whether the agency failed to proceed as required by law or made a decision unsupported by substantial evidence; courts do not reweigh evidence or substitute their judgment for the agency’s policy choice.
- An agency has discretion to accept or reject proposals for additional testing or experimentation; CEQA does not require postponing project consideration until recommended testing is completed.
- Conditioning approval on time-limited access for archaeological testing by non-developer parties can be a permissible mitigation choice when supported by reasons stated in the record.

## Conclusion

The court upheld the county’s subdivision approval because the EIR process adequately disclosed the potential archaeological impacts and the county’s chosen response—including a limited testing condition—fell within CEQA’s discretionary framework and was supported by substantial evidence under the deferential standard of review.


Soc'y for Cal. Archaeology v. Cnty. of Butte, 65 Cal. App. 3d 832, 135 Cal. Rptr. 679 (Ct. App. 1977)