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Plating Shop Design: Secondary Containment

Drip pans for secondary containment. How exactly do these work? I want to set the tanks on a metal frame about 8 to 12 inches above the ground. Would the pans set under the tanks on the ground or do you set the pans on the frame directly under the tanks. Lastly, how big do the pans have to be?

Thank you for the help, Andrew.

Andrew C [last name deleted for privacy by Editor]
- Compton, California
2000

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Hi, Andrew. Ideally, the pans would be on beams themselves, then additional beams within the pans would support the tanks. The advantage of this is that you can see that the pans are not leaking into the floor.

But cost and other realities can rear their heads, and the last several projects I did had the pans laying directly on the floor. That's really a pretty small compromise. The beams within the pans really ought to be fiberglass, not steel, though.

As for sizing, interpretations of EPA, OSHA, and local regulations usually indicate that the pans should hold 110 percent of the largest tank. This can usually be accommodated with pans 6 to 8" deep, and a couple of feet wider than the tanks, and spanning the compatible tanks and associated rinses.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2000

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Your state EPA, or local, may have an input on secondary containment quantity. The last I knew, the Feds did not specify, leaving it to how much risk of having a spill or bad leak get to "ground". My opinion is the more the better, but that has to be tempered with cost and feasibility.

One shop that I worked in, brought in a specialty contractor and fiberglassed the entire floor and over secured 4x4s to form a huge tank. My wife's shop welded in 1/2" polypropylene and made a 45' x45' x 5" giant tank. Similar for the waste treatment area. Costs a bit, but I was using enough PP to get a break and two of us welded it in on a weekend.

If the containment is on the floor, you can tell if a tank is leaking a bit easier than if the tank is setting directly on it. (personal opinion) EPA folks seemed to like that better. If it is in a pit, it is sort of mandatory.

James Watts
- Navarre, Florida
2000