Give your Hazardous Liquids a Safe Place to Spill into.

Confused and bewildered about federal secondary containment regulations? Trust us, we know how mind-numbing this stuff can be. So we broke it down for you into the five main things to consider under the EPA’s hazardous waste storage regulation 40 CFR 264.175, aka, “The Secondary Containment Regulations.”

1. Your secondary containment system must be impervious and free of cracks or gaps.

So, a little housekeeping is in order. Regularly (put it on your calendar) inspect your containment system to ensure there is no damage to the sump or to the unit itself. Any damage could prevent it from doing what you want it to do: contain liquids properly in the case of a container failure. It’s also important to be sure that the containment system is chemically compatible with whatever liquids could come into contact with it. Your containment system won’t be effective if the liquids it’s supposed to hold can damage it!

2. Primary containers can’t sit in their own waste, so your secondary containment unit must be either sloped or specifically designed to quickly and easily remove spilled or leaking liquid.

This one isn’t too hard to deal with. You can raise your containers on grates, decking or wood pallets. You can also add a drain to your secondary containment unit, so you can either pump or drain the liquids out of the sump quickly and efficiently if there is to be a release. What’s a sump? That’s where the liquid would collect if there was a release from the primary container. Sump capacity is the amount of liquid that can be held in a secondary containment unit, and it should equal or exceed the required secondary containment capacity.


3. The secondary containment system “must have sufficient capacity to contain at least 10% of the total volume of the primary containers or 100% of the volume of the largest container, whichever is greater.”

Okay, take a deep breath. This is the big one, the most well-known of the secondary containment regulations, but also the most confusing! This example may help:

You are storing two 55-gallon drums. So you have a total volume of 110 gallons.

10% of the total of all the containers (two 55-gallon drums) is 11 gallons. (10% of 110 gallons)

100% of the largest container stored is 55 gallons.

55 gallons is greater than 11 gallons, so you would need to have secondary containment for 55 gallons.

Got it? Now, remember, these are just the federal containment regulations. States and municipalities have to follow AT LEAST these values, but may be stricter. In fact, a lot of states require 110% containment of the largest container. So, it’s a good idea to check with your state and local municipality on their secondary containment regulations — you need to be compliant with everything!

4. Precipitation (also know as “run-on”) must be prevented from entering the secondary containment system unless the system has sufficient capacity to contain any run-on in addition to the volume capacity requirements.

Yes, you also have to worry about Mother Nature! When your containment unit is outdoors, any rainwater, snowmelt or other liquid that enters the sump of the secondary containment unit will take up capacity in the containment system. In the event of a spill, this could cause overflow. Regulators are really serious about this one. A no-brainer solution is to put your containment system under shelter or a self-contained cover. Of course, with some larger systems, this may be impossible! If that’s your situation, consider the worst storm your area has had in the last 100 years (NOAA has data on this if your memory isn’t quite that good) and calculate that into your capacity requirements.

5. Any waste that has spilled or leaked into the secondary containment area (or any accumulated precipitation like we talked about) must be removed in as timely a manner as is necessary to prevent overflow.

Simply put — check it out and clean it up! Any liquids that shouldn’t be in the sump take up volume capacity. You already know that is a big problem if you have a spill. You’ve spent so much time meticulously calculating your secondary containment volume requirements, the last thing you need is waste or precipitation in the sump. The displaced volume could save your system from overflowing in the event of a release from the primary container. Pay attention to your calendar and routinely inspect your sump and containment system. If you find any precipitation or waste, pump or drain it, filter the liquid, or absorb small spills with sorbent products.

Now that you have a better understanding of secondary containment regulations, you’re more prepared to help your facility achieve and maintain compliance. Check out the PIG products below or keep learning about how we can help you stay clean, safe and productive.