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Secondary Containment Calculation Worksheets

If you are the owner or operator of a Spill Prevention, Control, and Countermeasure (SPCC) qualified facility, you need to ensure that you have adequate secondary containment to prevent oil spills from reaching navigable water.

Example and blank worksheets used to calculate secondary containment capacity are available below. These worksheets address four specific scenarios and may not be valid for every facility. Although the SPCC rule does not require you to show the calculations of sized secondary containment in your plan, you should maintain documentation of secondary containment calculations to demonstrate compliance to an EPA inspector.

Disclaimer: These are simplified calculations for qualified facilities that assume:

  1. the secondary containment is designed with a flat floor,
  2. the wall height is equal for all four walls, and
  3. the corners of the secondary containment system are 90 degrees.

Additionally, the calculations do not include displacement for support structures or foundations. For Professional Engineer (PE) certified plans, the PE may need to account for site-specific conditions associated with the secondary containment structure which may require modifications to these sample calculations to ensure good engineering practice.

Please note: Word versions are fill-in the blank only. PDF forms compute calculations. You will need Microsoft Word to view some of the files on this page. See EPA’s Free Viewers and Readers page to learn more.

Single Vertical Cylindrical Tank Inside a Rectangular or Square Dike or Berm

Example Calculations
Blank Worksheet (Word)(7 pp, 253 K) | Blank Worksheet

Multiple Horizontal Cylindrical Tanks Inside a Rectangular or Square Dike or Berm

Example Calculations
Blank Worksheet (Word)(7 pp, 483 K) | Blank Worksheet

Rectangular or Square Remote Impoundment Structure

Example Calculations
Blank Worksheet (Word)(7 pp, 339 K) | Blank Worksheet

Constructing New Secondary Containment

Example Calculations
Blank Worksheet (Word)(7 pp, 383 K) | Blank Worksheet