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Legal Alert

San Francisco Proposal May Expedite Development of Contaminated Properties - But the Devil is in the Details

San Francisco Proposal May Expedite Development of Contaminated Properties - But the Devil is in the Details

A new law under consideration in San Francisco (the City) would require that properties must be tested for soil and groundwater contamination and any health threats be mitigated before the City will issue a grading or building permit. The requirement would apply to all properties with current or past industrial uses or in close proximity to underground storage tanks or freeways – or any other property that the Department of Public Health determines might be contaminated. CEQA compliance would not be required for activities taken under the approved law. Sellers and their agents would be responsible for providing buyers of affected properties with a copy of the law.

The law is proposed as an amendment to the Maher Ordinance, which requires soil testing and remediation of properties along San Francisco’s Eastern Shoreline. The amendment expands the scope of the Maher Ordinance to cover the entire City, and to require groundwater testing in addition to soil testing. The amendment also takes the unprecedented step of requiring property owners to test for and take responsibility for atmospheric deposition of contamination associated with freeways.

Unlike the Maher Ordinance, however, the proposed amendment focuses on abatement of health risks rather than remediation of the contamination. This shift could expedite the permitting process for contaminated properties and better protect future occupants of the building.

The most common health risk posed by contaminated property is the potential for contaminated vapors to migrate into buildings. In most cases, the risk of vapor intrusion can be managed cost-effectively even without soil or groundwater remediation. Vapor mitigation measures include vapor barriers, sub-slab depressurization systems, sub-slab venting, aerated floor systems, and building pressurization. Vapors can also be mitigated by modifications to building plans, such as constructing podium-style buildings or redesigning or relocating sub-surface elevators. Finally, exposure to vapors can be controlled by restricting sensitive land uses (e.g., residential or day care centers) in a deed restriction. Under the amendment, construction could begin before vapor mitigation measures are completed (or any remediation of soil or groundwater is conducted), provided the City approves the vapor mitigation plan.

The amendment could also impose greater consistency and certainty in the development process by supplanting the current practice under which remediation measures for contaminated properties are often imposed during the CEQA process as a mitigation measure to a negative declaration.

The amendment may expedite the permitting process for contaminated properties, but developers should be aware that mandatory testing for soil and groundwater could significantly increase overall project costs if unanticipated contamination is detected during such testing. Under state law, soil and groundwater contamination must be reported to state regulatory agencies, who may require additional investigation and remediation even after health risks have been addressed. In addition, these agencies could propose different or supplemental measures to address health risks beyond those measures approved by the City. 

The Board of Supervisors will be considering the new amendment on June 24, 2013. If it passes, potential buyers should consider testing properties during due diligence consistent with what the law will require to avoid discovering unanticipated contamination during the permitting process. Developers will need to develop strategies for addressing health risks, including building plans that accommodate any necessary mitigation for soil vapor intrusion and evaluation of health risks and mitigation measures associated with exposed soil. Sellers and their agents should be prepared to comply with the amendment’s disclosure requirements.