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Hazardous Materials Ordinance Changes
San Mateo County Board of Supervisors approved the proposed changes to County Ordinance 4.92 which became effective August 10, 2018.


The purpose of the change was to remove outdated requirements, align with existing State regulations, and provide clarification where needed. 

Questions or concerns about the revisions can be submitted in writing to

The previous Ordinance can be found here:
Previous Ordinance 4.92

The newly adopted ordinance can be found here:
Ordinance Ch 4.92 Storage of Hazardous Substances

Revision Highlights:

1.  Expands 4.92 to include all hazardous materials/waste programs overseen by Environmental Health Services to eliminate the need for separate ordinances.
2.  Formalizes the requirement to obtain and maintain a CUPA permit.
3.  Removes requirement that UST components always be disposed as hazardous waste upon removal.
4.  Formalizes CUPA authority to inspect unannounced during normal business hours and charge for afterhours inspections (after 6pm).
5.  Establishes civil and administrative enforcement structure for ordinance violations. 

The April 6, 2018 public meeting PowerPoint can be found here:
Proposed Ordinance PowerPoint