Even though flammable waste traps are out of sight, they shouldn’t be out of mind. If you manage a facility where vehicles drive or are stored, and they produce oily waste (like parking ramps, repair shops, car washes, etc.), you should have your flammable waste trap cleaned and inspected annually. We often speak with people who are uncertain about the purpose of these systems and how often they need inspecting, and we hope to address some of these questions and concerns here.
Flammable waste traps act as a catch basin for hazardous debris, sandy materials, and oily wastes found in parking garages, automobile service bays, and enclosed structures with vehicle traffic. The flammable waste trap separates the hazardous materials from the water waste, allowing just the waste water to flow to the city’s sanitary sewer and waste treatment plant.
A properly operating flammable waste trap will have a bottom layer of silt or sand, a layer of clean waste water that flows through the outlet pipe and down the city sanitary sewer, and a top layer of oily waste that sits on top of the clean waste water. While sand and oily wastes are the main materials found in the flammable waste trap, over the years we’ve also found flip-flops, crushed beer cans, and a few illegible credit cards stuck inside. So, you never know what you’ll find or what may be clogging your system.
The Minnesota Department of Transportation recommends that flammable waste traps be serviced once a year, but this is dependent on how much vehicle traffic there is in a structure. We recommend that an individual removes the cover on the tank once a year and makes note of the fluid level in the trap. If the flammable trap does not seem to ever have that much fluid in it, it may not need annual service.
An inspection can be completed by Yale in a few hours. We make note of the layer depths of the oily waste, clean water, and sand in the tank. If it’s determined the tank needs to be cleaned, we work with an authorized and certified Minnesota Pollution Control Agency hauler, or a septic pumping service. Yale oversees the cleaning or pumping of the tank and ensures the proper paperwork has been filed with the correct agencies regarding hazardous waste.
There are a few negative results that could come from ignoring your flammable waste trap. If the tank gets too full, oily waste could ooze from small gaps of the tank cover, or it might start coming up through the floor drains. And while flammable waste traps do not have a particularly offensive smell inside, you could start smelling fuel-type odors. If your tank is too full, you might find yourself in an emergency situation, which isn’t always easily remedied with these types of tanks.
In winter, Minnesotans drive around for months, collecting salt, road sand, gravel, and other chemicals on bumpers and wheel wells. This drips off in heated parking garages, into drains, and eventually into the flammable waste trap. The ideal time to have traps inspected and cleaned is in the late summer, when the rain has stopped and there are longer dry spells.
There are certain steps facility managers should take between annual cleanings. However, we must give you fair warning that what you see may not be pretty. The tank will likely have what appears to be a foot of congealed motor oil floating over a two-foot layer of sand and gravel.
We recommend that you keep the tank cover clean from sand and water to make it easier when it comes time to remove the bolts that keep the airtight lid sealed. If there are oily waste spills in a structure, try to contain these spills using fuel- and oil-absorbent pads. Every attempt to prevent as little sand or oily waste from falling into the flammable waste trap will help keep it functioning properly.
Yale has kept flammable waste traps across the Twin Cities worry-free for years. And as we head into spring, we recommend you start thinking about having yours serviced. Please contact me with any questions or to schedule your inspection.
