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Secondary Containment

In order to prevent releases due to structural failure, corrosion, or spills and overfills for as long as the UST system is used to store regulated substances, all owners and operators of new UST systems must obtain permits in accordance with Section 280.23.

In addition, tanks and piping installed or replaced after May 23, 2008 must be secondarily contained and use interstitial monitoring. Secondary containment must be able to contain regulated substances leaked from the primary containment until they are detected and removed and prevent the release of regulated substances to the environment at any time during the operational life of the UST system. For cases where the piping is considered to be replaced, the entire piping run must be secondarily contained.

Examples of secondary containment:

  • Double-wall tank
  • Double-wall piping
  • Under-dispenser containment (dispenser sump )
  • Submersible turbine pump sump

Instances where secondary containment is required:

  • Any new tank installation
  • Any new piping installation
  • Any new dispenser installation
  • A replacement tank
  • A replacement of an entire piping run
  • A replacement dispenser (exception: a replacement European suction dispenser where no change to piping occurs )
  • Piping repairs over a consecutive 12-month period that equals more than 25 percent of the existing piping run

Secondary containment systems must:

  • Contain all regulated substances released from a UST system until they are detected and removed.
  • Prevent a release of a regulated substance to the environment at any time during the operational life of the UST system.
  • Be monitored monthly for a release using interstitial monitoring.