J. J. Keller® Compliance Network Logo
Start Customizing Your Profile for Free!
Update to Professional Trial!

Experience Everything Compliance Network Has to Offer

Already have an account?
Thank you for investing in EnvironmentalHazmat related content. Click 'UPGRADE' to continue.
Enjoy your limited-time access to the Compliance Network Professional Trial!
A confirmation welcome email has been sent to your email address from ComplianceNetwork@t.jjkellercompliancenetwork.com. Please check your spam/junk folder if you can't find it in your inbox.
Thank you for your interest in EnvironmentalHazmat related content.
You've reached your limit of free access, if you'd like more info, please contact us at 800-327-6868.
Secondary containment options
  • The EPA mandates the use of one of four specific options to meet the secondary container requirements: an external liner, vault, double-walled tank, or alternative equivalent device.
  • Examples of secondary containment for ancillary equipment are trenches, jacketing, or double-walled piping.

The Environmental Protection Agency (EPA) mandates the use of one of the following four specific options to meet the secondary container requirements in Subpart J:

  • The use of an external liner that is designed to work in conjunction with a barrier. This combination should be able to contain releases in a specific area and hold those releases until the containment area is cleaned.
  • The use of a vault, an underground area with specific design requirements to contain releases that are not visible to the operator.
  • The use of a double-walled tank (sometimes called a tank within a tank) is considered to be the most protective of releases of hazardous wastes outside the outer containment area; and
  • The use of an alternative equivalent device, subject to the approval of the state or EPA.

The use of an external liner (264.193(e)(1) and 265.193(e)(1))

An external tank liner is designed to provide protection against lateral or vertical migration of leaking waste by completely surrounding the unit with an impermeable material. A liner can be made with many different types of materials such as synthetic membranes, concrete, clay, bentonite, soil, cement, or asphalt. The exact type of material or combination of materials used depends onsite conditions, waste characteristics, and climate.

The external liner system must be large enough to contain 100 percent of the capacity of the largest hazardous waste tank within its boundary. Stormwater run-on and infiltration should be minimized by using dikes and diversion ditches because it can increase the rate of tank corrosion. If stormwater infiltration is not controlled in this manner, the system must have enough additional holding capacity to contain precipitation resulting from a 25-year, 24-hour storm event.

The use of a vault (264.193(e)(2) and 265.193(e)(2))

In a vault system, the hazardous waste tank rests in an underground chamber usually constructed with concrete floors and walls and an impermeable cover. A closed aboveground building that houses a hazardous waste tank may also be considered a vault for purposes of secondary containment. Because of the inherently porous nature of concrete, the primary building material for vaults, these units must have a waterproof exterior and be lined inside with a leak-proof sealant. To further minimize contact with moisture, tanks inside vaults should rest on cradles or saddles, rather than on the vault floor. Tanks in these units may also be surrounded with backfilled earthen materials. Although filling the vault with soil limits visual inspection of the hazardous waste tanks, the backfill can lend structural support to the unit and tanks and prevent the explosion of any ignitable wastes that may leak from the tank.

The use of a double-walled tank (264.193(e)(3) and 265.193(e)(3))

A double-walled tank can be described as one tank completely enclosed inside another with a leak detection monitoring system installed between the two (in the interstitial space). The most common construction materials for this secondary containment option include corrosion-protected metal, epoxy, fiberglass, or metal with a synthetic membrane wrap. Such a containment system must be designed and constructed so that any release from the inner tank is completely contained by the outer shell until the accumulated materials are removed. The leak detection system must be capable of detecting leak activity between the tanks within 24 hours or at the “earliest practicable time.”

Ancillary equipment and secondary containment

All ancillary equipment must have full secondary containment in addition to the tank itself. Examples of secondary containment for ancillary equipment are trenches, jacketing, or double-walled piping. When inspected daily, however, the following equipment is exempt from this requirement:

  • Aboveground piping (not including flanges, joints, valves, and connections);
  • Welded flanges, welded joints, and welded connections (including piping that is fused together with solvent cement or heat fusion);
  • Seal-less or magnetic coupling pumps; and
  • Aboveground pressurized piping systems with automatic shut-off devices.