Does your business or facility store chemicals, waste, or other hazardous liquids? While containing the substance itself is important, so is having a system in place for preventing spills. In this case, around every primary container needs to be a secondary containment system.
Guidelines for secondary containment are specified by the Resource Conservation and Recovery Act (RCRA) 40 CFR 264, including the use and management of containers and tanks. While standards for container and tank systems are similar, both have separate specific guidelines.
A container must have a crack- and gap-free base, one impermeable to all leaks, spills, and precipitation. At the same time, the system is in place to catch spills from the primary storage container and, therefore, must be designed with a draining system and be able to prevent run-on. If such a leak occurs, however, the liquid must be removed from the sump as soon as possible to prevent overflow.
Tank systems for secondary containment follow a similar set of guidelines with a few notable differences. Most notably, a tank must contain overflow in order to prevent contamination of soil, ground, and surface water. Because a tank system may be placed outdoors, the container needs to handle pressure, contact with waste, climate conditions, and stress from daily operations. Additionally, the tank must be placed on a foundation or base that supports secondary containment.
Like containers, tanks too must be designed to drain any leaks, and if such a spill occurs, the chemical or liquid must be removed as soon as possible or at least within 24 hours.
As far as containment capacities, a container is expected to hold 10 percent of all primary containment systems, while both a container and tank should have enough volume for the contents of the largest primary container. Although liquids often need secondary containment, other substances do, as well: solids in quantities greater than 550 pounds, multiple containers totaling 10,000 pounds or more, or open liquids of more than 1.1 or 5.3 gallons.