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Court Clarifies Mitigation Needs for Buried Artifacts, Plants, and Trees

Court Clarifies Mitigation Needs for Buried Artifacts, Plants, and Trees

Many environmental impact reports and negative declarations will breeze through analyses of a development project’s impacts on cultural resources. To this end, it is common to see CEQA documents acknowledge the possible existence of a Native American or other cultural resource, and then employ “cookie-cutter” mitigation measures that essentially require construction workers to stop work upon discovery of a potentially significant artifact, whereupon a certified archeologist will implement “a data recovery program” or take other, generalized actions. Under the appellate court’s decision in Agoura Cornell Knoll v. City of Agoura Hills, it is clear that a lead agency must require more, at least where a potentially valuable resource is known to be buried somewhere on a site.

This decision also clarifies the degree of detail required for sensitive plan and protected tree mitigations, and includes some enhanced requirements, especially where an agency has approved a negative declaration or mitigated declaration (triggering a standard of judicial review that is more favorable to project opponents).

Cultural Resources Analyses

In this case, the City studied whether a mixed-use commercial and residential development would have the potential to harm cultural resource “CA-LAN-1352,” a reference to a tribal cultural resource consisting of lithic artifacts (e.g., stone tools) and other cultural resources. The mitigated negative declaration for the project (referred to here as the MND) recommended that the resource be avoided but, if avoidance was not feasible, that the following be implemented: (1) construction-related activities be monitored by an archaeologist and Native American monitor; (2) that work stop within a 100-foot radius if construction workers came across a potential resource; and (3) that “appropriate actions” be taken, including the implementation of a “Phase II data recovery excavation program” if avoidance wasn’t possible. In describing this Phase III program, the MND indicated it had to be completed by a professional archaeologist, and would have to include the preparation of a work plan, fieldwork, laboratory analysis of recovered materials, and the preparation of special studies and a technical report.

The court held this wasn’t good enough. This recipe for mitigation, the court held, constituted an improper deferral of mitigation, as the CEQA analysis failed to identify whether the resource could be avoided in the first place, nor any performance criteria for evaluating the feasibility of avoidance as an alternative to excavation. The court wanted criteria — some sort of metric — and seemed perturbed, in particular, that the analysis failed to define the boundaries of the archaeological site.

Nor was the data recovery plan sufficiently clear, in the court’s opinion. To this end, the MND provided for a generalized list of measures to be undertaken, such as the “preparation of a technical report” that “shall include a mitigation monitoring and reporting plan,” but did not define the contours of this plan nor specify criteria for determining whether it would mitigate potential harm to the resource.

All this, the court said, constituted substantial evidence to support a fair argument that the prescribed mitigation measures improperly deferred mitigation of the project’s impacts, and were insufficient to avoid or reduce those impacts to an insignificant level.

Sensitive Plant Resources

The project opponents challenged the MND on allegations that impacts to two sensitive plant species were not mitigated effectively. The court agreed the mitigation had a number of flaws, some of which echoed flaws found in the cultural resources analysis. For instance, the mitigation measures required avoidance of the plants where feasible, which entailed adherence to a 200-foot buffer or an “active maintenance plan.”  But the MND did not specify a performance standard for determining whether avoidance was feasible. Moreover, various “backup” plans, which included the restoration of habitat on- and off-site, were flawed. Here, the record contained evidence from the California Department of Fish and Wildlife that restoration of plants using transplanting or topsoil collection techniques were “experimental” for the listed species, with uncertain chances of success. Second, the MND didn’t provide for a contingency where salvage and replanting efforts failed. While a belt-and-suspenders approach is theoretically workable, then, at least one of the proposed measures must function in a meaningful way, and incorporate performance standards with quantifiable or other specific thresholds. Without a clear, transparent view into the decision-making process, a court will find there has been improper deferral of mitigation.

Oak Trees

This CEQA decision could be read to dial up the requirements for evaluating impacts to protected trees — here, oak trees — and it is not the first in which a court has held an agency’s feet to the fire for failing to adequately explain how it will mitigate impacts to protected trees. (See Center for Sierra Nevada Conservation v. County of El Dorado (2012) 202 Cal.App.4th 1156 [“the trial court's reasoning that the oak woodland management plan ‘deserves a chance to be tested in the real world’ lies at odds with the California Supreme Court's admonition to conduct EIR review before approval of a project.”].) However, this case marks the first published decision in which a court has overturned an agency’s approval of a CEQA document on the grounds that the agency failed to disclose how oak trees will be impacted by grading that disrupts subsurface water flows.

From the standpoint of practice, this decision is important because biological surveys, including arborist reports, do not always evaluate how grading will impact the health and viability of a tree. Accordingly, where development of a project site will involve mass grading, project proponents will need to think about whether this grading will create a water deficit in areas where protected trees grow. The mitigation here also failed for lack of detail; there was no direction with respect to off-site tree planting programs (e.g., how many trees should be planted), or any meaningful evaluation of the availability of planting sites.

For More Information, Please Contact:

Sean Marciniak
Sean Marciniak
San Francisco, CA