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Underground Storage Tanks (USTs)

Low Liquid Level UST Containment Sump Testing Procedures

This document provides procedures for low liquid level hydrostatic testing as one method of meeting the requirements in 40 CFR 280.35 for periodically testing the integrity of certain containment sumps. The federal underground storage tank (UST) regulation at 40 CFR 280.35 requires that owners and operators using interstitial monitoring of UST system piping as their primary release detection method prevent releases to the environment by ensuring the integrity of each containment sump used for interstitial monitoring of piping.

Sample Form For Documenting Compliance With Low Liquid Level UST Containment Sump Testing Procedures (DOCX)(2 pp, 36 K, June 2018)

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