Organization Information

Environmental Management

Required Monthly Inspections for Aboveground Storage Tanks

Aboveground Storage Tanks (ASTs) must be inspected at least once a month to comply with regulatory requirements, as well as Postal Service™ policy (see Administrative Support Manual, Chapter 69, “Environmental Management and Compliance”).

The monthly inspection requirement applies to ASTs of any size that contain hazardous materials, such as:

n New and used oil.

n Gasoline, including diesel fuel.

n New and used antifreeze.

n Windshield washer fluid.

n Diesel exhaust fluid.

n Heating oil.

These inspections help prevent the release of oil or other hazardous materials into the environment. Under this policy, the site installation head, or their designee, must:

n Conduct and document a visual inspection of each AST on a monthly basis.

n Ensure each AST has a label that identifies the contents and volume.

n Address any issues identified during the inspection.

n Promptly address spills and respond with appropriate actions.

For specific information about managing ASTs (including inspection forms), use the following resources:

n Environmental Compliance Bulletin: Aboveground Storage Tank Management at

n Environmental Compliance Bulletin: Heating Oil Tank Management at

n A brief video available for credit in HERO that provides basic instruction on how to inspect ASTs at

Some sites that store larger volumes of oil may have a dedicated Spill Prevention, Control, and Countermeasure (SPCC) Plan. Sites with SPCC Plans must use the inspection form in the site-specific SPCC Plan.

For general information about environmental compliance, review the Environmental Affairs website at or consult your designated environmental contact at