Underground Storage Tanks (UST's)

The Hazardous Materials Division regulates the storage of hazardous materials (gasoline, diesel, heating oil, kerosene, aviation fuel and others) in underground storage tanks (USTs).


UST News:

Flyer: All UST Facilities must have a "Designated UST Operator"


Additional UST Information:

A regulated “underground storage tank” is any one or combination of tanks, including piping connected thereto that is used for the storage of hazardous substances and that is substantially or totally beneath the surface of the ground. The vapor control components of UST systems are regulated by the EDC Air Quality Management District. Regulated USTs are permitted and inspected annually. Additional permitting and inspections are required for UST system installation, repairs and closures.

California Code of Regulations Title 23, Section 2638 & 2643, requires that the UST Owner or Operator shall notify the Certified Unified Program Agency (CUPA) at least 48 hours in advance of conducting any installation, repair, replacement, calibration or certification of monitoring equipment and before conducting a tank or piping integrity test. For UST sites in El Dorado County, please notify our Department with either electronic and/or fax notification. Please email notifications to:emd.info@edcgov.us or fax notifications to: 530-295-2747


UST Ordinance No. 4332

Guidelines for UST Installation / Modification / Repair

Guidelines for UST Closure

Every owner of an underground storage tank must register with the BOE and pay the underground storage tank maintenance fee for every gallon of petroleum product placed into the underground tank. If you own property where an underground storage tank is located, you are usually considered the owner of the underground storage tank. If you operate an underground storage tank but do not own it, you are not liable for the fee. An operator is defined as the person who controls or is responsible for the daily operation of the tank. Generally, if you lease an underground storage tank, you will be considered an operator, not an owner, unless your lease provides otherwise. The Underground Storage Tank Maintenance Fee Application can be found at California Board of Equalization

For more information contact BOE's Fuel Taxes Division:
Fuel Industry Section
Fuel Taxes Division, MIC: 30
State Board of Equalization
P.O. Box 942879
Sacramento, CA 94279-0030
(916) 322-9669 phone
(800) 400-7115 toll-free phone
(916) 323-9352 fax

Frequently Asked Questions


What is a “tank”?
“Tank” means 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.

Are there non-regulated tanks?

“Underground storage tank” does not include:

  • Tanks with a capacity of 1,100 gallons or less that :

    • Store motor vehicle fuel located on a farm and is used for agricultural purposes and not for resale.

    • Are located on a farm or at the residence of a person that stores home heating oil for consumptive use on the premises where stored

  • Structures, such as sumps, separators, storm drains, catch basins, oil field gathering lines, refinery pipelines, lagoons, evaporation ponds, well cellars, separation sumps, lined and unlined pits, sumps and lagoons. A sump that is a part of a monitoring system required under Section 25290.1, 25290.2, 25291, or 25292 and sumps or other structures defined as underground storage tanks under the federal act are not exempted by this subparagraph.

  • A tank holding hydraulic fluid for a closed loop mechanical system that uses compressed air or hydraulic fluid to operate lifts, elevators, and other similar devices.