What is an Underground Storage Tank?

An underground storage tank (UST) is any one or combination of tanks, including pipes connected thereto, that is used for the storage of hazardous substances that is substantially or totally beneath the surface of the ground. The definition of “tank” is a stationary device designed to contain an accumulation of hazardous substances which is constructed primarily of nonearthen materials, including, but not limited to, wood, concrete, steel, or plastic that provides structural support. An underground tank system mean an underground storage tank, connected piping, ancillary equipment, and containment system, if any.

Installation, Repair, Modification, and Closure Requirements

In order to install, repair, modify, or close an UST, a permit application must be submitted to the CUPA. Modification includes the installation or replacement of any leak detection equipment. The permit application will be reviewed by the CUPA and if the application is approved a permit is issued to the owner/operator. These permits must be completed by the date identified in the permit. Please email Sarojini.balachandra@dtsc.ca.gov for the most updated permit applications. 

All permit applications must also include the following documents:

• Site map
• Contractor’s license 
• ICC license of technician performing the work
• Training certificate issued by the manufacturer 

More information may be requested at the time of the review of the permit application. 

UST Forms

Financial Responsibility Forms

• Letter from the Chief Financial Officer
• Certificate of Financial Responsibility
• Financial Responsibility Guidelines

Leak Reporting

• Unauthorized Release Forms and Instructions

CUPA Forms

• California Environmental Reporting System (CERS)

UST Guidelines

• Response Plan
• UST Installation Guidelines
• Statement of Understanding and Compliance Form

UST Contractors Report Forms

• UST Reporting and Inspection Forms
• Spill Container Test Report Form
• Designated Underground Storage Tank Operator Visual Inspection Report
• Facility Employee Training Certificate 
• Overfill Prevention Equipment Inspection Report Form
• Secondary Containment Testing Report Form
• Monitoring System Certification Form
• Verification Analyses

UST Permit Fee Summary

• Trinity County Fee Schedule