Underground Storage Tanks
Placement Restrictions (F-3208.2)
- Flammable liquid storage tanks shall be placed a minimum of 1 foot from any wall and 3 feet from any lot line.
- Combustible liquid storage tanks shall be placed a minimum of 1 foot from any wall and 1 foot from any lot line.
Excavation Restrictions (F-3208.3)
- Minimum backfill underneath each tank shall be 1 foot.
- Maximum depth shall be twice the diameter of the tank or 23 feet, whichever is less.
Ground Water & Flood Protection Requirements (F-3208.4)
- Hold down straps per manufacturer's specifications.
- Hold down pad separated from the tank by a minimum of 6 inches (steel tank) or 12 inches (non-metallic tank).
Installation & Backfill Requirements (F-3208.5)
- Minimum backfill for a steel tank: 12 inches
- Minimum backfill for a non-metallic tank: 24 inches
- Backfill must be non-corrosive, inert material (for example, pea gravel, crushed rock, sand, etc.)
- Minimum diameter (pea gravel): 1/2 inch
- Maximum diameter (pea gravel): 3/4 inch
- Minimum diameter (crushed rock): 1/8 inch
- Maximum diameter (crushed rock): 1/2 inch
Tank Coverage in Traffic Areas (F-3208.6)
- Option No. 1: minimum backfill of 18 inches with 6 inches of reinforced concrete.
- Option No. 2: minimum backfill of 30 inches with 6 inches of asphalt.
- Note in both cases, the cover must extend a minimum of 1 foot beyond the vertically projected line of the storage tank.
Corrosion Protection (F-3208)
All steel underground storage tanks and/or associated metallic equipment/devices shall be protected from corrosion. Metallic connections to steel tanks shall be by dielectric fittings. Metallic hold down straps shall be electrically isolated from steel tanks.
Leak Detection (F-3208.9)
All underground storage tanks and piping systems shall be monitored in an approved manner.
Tank Testing (F-3208.10)
After installation and prior to adding flammable or combustible liquids, the tank shall be pressure tested to a minimum of 3 psi and a maximum of 5 psi for 60 minutes (1 hour) without additional air/gas being added.
Abandonment of Underground Tanks (F3208.11)
After 1 year or if determined to be leaking, the underground storage tank and its associated piping must be removed and the site restored/remediated is an appropriate manner.