Fuel Storage: Underground & Above Ground


Tank Closure

An Underground Storage Tank (UST) or Aboveground Storage Tank (AST) requires a permit (UGS) for closure of tank(s) system either by removal or abandonment in place.

Required Information:

Location of tank(s)
Size of tank(s)
Type and use of regulated substance stored
Method of inerting or purging UST’s or AST’s
Site assessment in accordance with UST Regulations (9VAC25-580)
Closure in place – material to be used to fill UST’s
Zoning Approval – stamp or letter (record of tank size, location, and date of abandonment, where applicable)

Closure of UST system(s) shall be in accordance with Section 32-250.90 the Code of Prince William UST Regulations as adopted by the Virginia Department of Environmental Quality and the Board of Housing and Community Development, the Virginia Uniform Building Code (VUSBC) and all referenced standards.

Tank Removal

Building Development inspections will consist of the following:

On-site inspections by PWC inspectors to witness that the tanks are removed
Witness that soil or water samples are taken at the time of tank removal if applicable
Document method of inerting or purging of tank(s) if applicable
Approve back filling of excavation if no release is detected
If release is detected, soils must be stored on site and adjacent areas protected, or soils are to be removed to a proper site for disposal
Tanks are to be marked – 'unfit for human consumption'

A UGS permit will be finalized when the soils report is received, if a release has taken place.

Closure in place may not be permitted, if it is suspected that the tank(s) leak, or it is known that the tank(s) leak. If permitted, the tank may be filled with an inert material such as sand a slurry, concrete mix foam, or pea gravel. Boring samples shall be required from around the tank to ensure that a release has not taken place.

Two copies of the site plan with the tank location shall be submitted to the Zoning Office if closure is by abandonment in place.

For UST removal/closure information, call 703-792-6955 (Chief of Mechanical Inspections).


Storage tank systems consist of the installation of underground storage tanks (UST) or aboveground storage tanks (AST) for the storage or dispensing of regulated substances.

All storage tank systems are regulated by PWC ordinance 32-250.90, UST Regulations Adopted by the Virginia Department of Environmental Quality, the Department of Housing and Community Development, the International Mechanical Code, the International Building Code, the International Fire Prevention Code, and the International Fuel Gas Code.

Permits for the installation or replacement of UST – AST storage tank systems will not be issued without prior approval from the PWC Zoning Department. Approval is to be attached to plan(s).

Installation of UST/AST systems shall be in accordance with the manufacturer’s installation guidelines – NFPA 30 NFPA 30A NFPA 31 NFPA 58 and the codes noted previously.

Site plans are required to show the location of tank(s) in relation to property lines, structures on site and structures close to the property line off site where tank(s) are to be located.  (For residential installations, an approved house plat is required).

Tank installation plans (minimum of two sets) shall consist of the following:

Show fill pipe and vent
Piping layout – type of piping material to be used including regulators (if needed)
Size of tank(s) – dimensions and gallons
Type of tank – steel or fiberglass - single wall double wall or vaulted
Type and use of the regulated substance
Equipment specification list – monitoring devices – cathodic protection devices
Depth of tank(s) and type of cover (asphalt or concrete) if UST
Type of backfill to be used
Type of anchoring signed and sealed calculations (if needed) wet holes
Location of emergency shut-off device(s) and valves
Approval of zoning administrator
UL listing number

On any installation of storage tank systems when the dispensing of the regulated substance is for resale or fleet fueling, a Hazardous Use Permit (HUP) is required. The Hazardous Use Permit is issued by the PWC Fire Marshal’s Office (FMO) after final inspections are performed, approved and the occupancy permit is issued or reissued.

On dispensing equipment other than the monitoring systems, that normally are low voltage, drawings and an electrical permit is required.

Inspections are required on all phases of the storage tank systems beginning with the above ground testing of the tank. All inspections performed by this department shall be in accordance with the standards or regulations previously noted above.

For UST – AST installation information, call 703-792-6955 (Chief of Mechanical Inspections).

For the Fire Marshal, call 703-792-6360.

For Inspections information, call 703-792-6955.  To schedule inspections, call the automated phone system at 703-792-6970 or visit www.pwcgov.org/eInspections.

Concealment Inspection

Above ground inspection of tank(s) w/ test or vacuum (Soapy water applied to tank surface)
Placement of tanks and holddowns (deadmen) if applicable (backfill may be placed after this inspection)
Test on product vapor recovery and vent piping per manufacture installation instructions

 Final Inspection

Check for signage
All equipment is operating
Check emergency shut off

After inspections are completed, before the service station can be opened to the public, the Fire Marshal’s office is to be contacted for inspection and a Hazardous Use Permit (HUP) will be issued.

To schedule inspections, call the automated phone system at 703-792-6970 or visit www.pwcgov.org/eInspections.

For UST – AST inspection information, call 703-792-6955 (Chief of Mechanical Inspections).

For the Fire Marshal, call 703-792-6360.


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