Frequent Questions

Secondary containment calculations in SPCC Plan

The SPCC regulations in 40 CFR §112.7(c) require facilities to provide appropriate containment or diversionary structures or equipment to prevent discharges as described in §112.1(b). Does a facility's SPCC Plan have to include calculations to demonstrate compliance with the §112.7(c) general secondary containment requirements?

EPA does not require facilities to keep calculations of secondary containment in an SPCC Plan; however, the Plan must include enough detail to describe the efficacy of the measures used to comply with the requirements in §112.7(c). EPA recommends that the facility owner or operator maintain calculations that serve as the basis for the capacity of the secondary containment system such that if questions arise during an inspection, the calculations will be readily available for review. Calculations may be provided in the Plan as part of the documentation to support the adequacy of containment measures employed at the facility. Industry guidance (e.g., API Bulletin D16, Third Edition, December 2002) recommends that facility owners or operators include any secondary containment capacity calculations or design standards with the Plan.

Sample calculations of containment size are available in Chapter 4 of the SPCC Guidance for Regional Inspectors, available at the following URL:


Have more questions? Submit a request