If you use liquids at your facility, then you probably deal with everything from steel drums to plastic buckets. No doubt you’ve heard the term secondary containment, as in: “those storage drums need secondary containment.” But did anyone ever tell you what it really means or what it takes to do it right — in plain English? We didn’t think so.
Any container that’s holding a liquid — whether it’s a 5-gallon bucket or a 55-gallon drum — is the primary container. The problem is that primary containers can leak, crack, tip over or otherwise fail without warning, and usually at the worst possible moment.
Secondary containment is your backup system — a container for your container. It can be as simple as a tray or as complex as concrete berms, but the result is the same: all of the liquid from your primary container is under control, even in a worst-case scenario.
If you’re dealing with hazardous waste, secondary containment is a requirement under EPA’s hazardous waste storage regulation [40 CFR 264.175]. What if you’re storing virgin hazardous materials? You still need secondary containment because if you have a spill, the material is immediately considered a waste that falls under the regulation.
Here are the seven basic points of secondary containment:
- Your secondary containment system should be composed of materials that are chemically compatible with the liquid in your primary container.
- Your system should be impermeable and be free of cracks or gaps.
- Your system should be designed to allow you to drain the spilled liquid. This may mean choosing containment units with drain plugs or building permanent containment on a slope.
- Your primary containers can’t sit in the spilled liquid. Pallets and containment units typically position the sump under a grate to solve this problem.
- You must have enough capacity to contain the liquid. The federal requirement is 10% of the total volume of all the containers stored together or 100% of the largest container — whichever is greater. Many states require 110%, so check your local fire code for specifics.
- Your system should prevent stormwater accumulation (run on). Storage sheds and covered containment units keep rain and snow out of the sump, but in an uncovered outdoor system you need to add weather-related liquid accumulation to your overall capacity.
- If any liquid spills or leaks into your secondary containment system, or if you have accumulating rain or snow, you need to remove it as soon as possible to prevent an overflow.
You tell us: What other questions do you have about primary containers and secondary containment? Leave a comment below!