DEEP is continuing to carry out its mission and provide services while keeping both the public and our workforce safe during the COVID-19 pandemic. Click here for the latest updates on DEEP's response to COVID-19. DEEP COVID-19 Response

Secondary Containment

In compliance with the federal Energy Policy Act of 2005 (EPAct), DEEP has passed and is now implementing amendments to the existing UST Regulations, effective May 31, 2012.  The amendment included Secondary Containment requirements per RCSA 22a-449(d)-102.  Highlights of these requirements are as follows:
  • New UST systems must include:
    • liquid tight under-dispenser containment sumps with sensors, and
    • liquid tight piping containment sumps with sensors.
  • The requirements for new under-dispenser containment must be met when:
    • replacing more than fifty (50) percent of the dispensers at a facility, the requirements for new under-dispenser containment sumps must be met for all dispensers at the facility or
    • replacing a dispenser and more than fifty (50) percent of the flex-joint or flexible piping that is directly beneath the dispenser.
  • Upon installation and prior to operating any newly installed double-walled UST system:
    • testing must be performed which demonstrates that liquids which accumulate in any part of the UST system (including sumps) will not be released to the environment, and
    • re-tests will be required every five (5) years thereafter, although this requirement does not apply to certain secondary containment systems that are hydrostatically or vacuum monitored continuously.
  • Under-dispenser containment sumps and piping containment sumps that require repairs must be tested to demonstrate that the repaired sump meets the requirements of a new under-dispenser containment sump or new piping containment sump.
Secondary containment questions may be directed to the Storage Tank and PCB Enforcement Program at 860-424-3374 or


Content last updated September 2019