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Aboveground Storage Tanks (AST)


An AST is a system consisting of a tank or combination of tanks, and the piping and ancillary equipment connected to it within its containment structure. Systems containing more than very small quantities of regulated substances (PDF) where the system volume is greater than 250 gallons and where 10 percent or less of the system volume is underground are regulated in Pennsylvania by the Storage Tank Program unless one of the exemptions apply. Underground means below the surface of the surrounding soil (ground or pavement), but not in an area which is completely open for tank inspection such as in some mines, basements, or vaults.

Work (except for routine maintenance) on a regulated tank system must be performed by a properly certified tank handler (installer). Inspections required by the storage tank regulations must be performed by a properly certified tank inspector. A DEP certified inspector should be involved in AST construction projects, prior to initiation of the construction and during critical times, so that the inspector can observe construction work and determine that industry standards and project specification are followed and applicable tests are properly performed, and that the tank system is suitable for operational service. Owners can choose from the list of certified companies when searching for DEP certified installers and inspectors to work on their tank systems.

Click the link below to access a list, updated daily, of Storage Tank Certified Companies. You may search by DEP Region, County, and Certification Category. This list may be exported in a variety of formats, or to obtain a printed copy of the latest list, call the customer service unit at 1-800-42-TANKS (toll-free within PA) or 717-772-5599 (local and out-of-state).

People who want to perform tank handling activities on regulated tanks in the Commonwealth of Pennsylvania must be certified. See the Certification page for more information.

Aboveground storage tank systems that are no longer needed or are unsuitable for regulated substance storage must be properly closed-in-place or removed.

This list of standards and practices (PDF) may be used to comply with storage tank regulations.

Further information on storage tanks as well an online storage tank search can be found at our regulated tank listing page.