Underground Storage Tanks

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The Environmental Programs Division regulates the construction, operation, repair and removal of underground storage tank (UST) systems. The Underground Storage Tank (UST) Program is one element within Environmental Program’s CUPA program.  The UST program is administered within the jurisdictional limits of the City of Union City. 

Typically, USTs are used to store large amounts of hazardous materials such as gasoline, diesel, biodiesel, and waste oils – buried out of sight and, in many instances proximate to the groundwater table, they present unique environmental and safety risks. 

The purpose of the UST Program is to protect public health, the environment and groundwater from potential contamination or adverse effects associated with unintended releases from the underground storage of hazardous materials.  A permit to operate a UST system in the City of Union City is required by state law and local ordinance (Chapter 6.7 of Division 20 of the California Health and Safety Code and Title 23 of Division 3 of the California Code of Regulations). State law mandates annual UST monitor certifications, facility inspections and payment of fees. Close coordination between inspectors, contractors and the regulated community is a priority for the City. 

Program Overview

Routine Testing/Inspections 

  • The UST monitoring system and spill buckets must be tested annually, click here
  • For UST systems that are not programmed for positive shutdown and fail-safe, an annual pipeline integrity test is required
  • For tanks installed prior to July 1, 2003, secondary containment testing (SB 989) is required every 36 months, click here
  • Beginning October 1, 2018, overfill prevention equipment must be inspection at least once every 36 months, click here
  • Beginning October 1, 2018, underground storage tanks (USTs) defined as Emergency Generator Tank Systems in Health and Safety Code, division 20, chapter 6.7, section 25281.5(c) that are connected to underground pressurized piping are required to be equipped with an Line Leak Detector (LLD) in accordance with California Code of Regulations, title 23, division 3, chapter 16, section 2636(f)(5). LLDs are required to be certified for proper operation and calibrated at least once every 12 months, click here. 
  • Underground tanks with single-walled components or unique circumstances may require additional testing. Please contact your inspector for guidance

48 Hour Notification 

UST owners and/or operators are responsible for notifying Environmental Programs (CUPA) of UST testing at least 48 hours prior to ordinary testing and retrofit/repair related testing (23 CCR, Section 2638). This notification allows staff the opportunity to witness the testing. Many testing companies may provide regulatory agency notification as a courtesy service to their clients, but the tank owner and/or operator is ultimately responsible for notification if not received by us.

Environmental Programs (CUPA) accepts notifications via email and regular mail. Email is preferable, as it allows for easy tracking and reduces paper usage. Notification may be submitted to any of the following:

  • Email: ustnotifications@unioncity.org  
  • Send by certified mail: 34009 Alvarado-Niles BLVD, ATTENTION ENVIRONMENTAL PROGRAMS/CUPA, Union City, CA 94583

The 48-hour requirement does not include weekends and holidays. Failure to notify Union City (CUPA) of UST testing may result in the necessity of a retest.

Test Results

Monitoring system certification, spill bucket testing, and/or pipeline integrity testing, containment testing must be submitted to Environmental Programs (CUPA) within 30 days (23 CCR, Section 2638). Environmental Programs (CUPA) accepts test reports via email and certified mail.  Email: ustnotifications@unioncity.org  

Additional Questions?

If you need more information or have questions concerning UST requirements or other information, please contact:

Environmental Programs Department (CUPA)
34009 Alvarado-Niles BLVD.
Union City, CA 94587

(510) 675-5367