There are dozens of components that go into a complete secondary containment system. However, there are some basics that form the backdrop of the containment plan. These considerations apply to all secondary containment designs, including the extensive liner and drain systems needed for oil and fuel fields. Understanding the five main components of design, for oil and fuel secondary containment, will get the project started off on the right foot.
1. Rainwater Control
Excess rainwater and runoff are a problem in every kind of secondary containment system. When containment is designed only to hold a specific amount of spilled oil or fuel, any extra water gathering in the basin or drain will cause the entire system to overflow. This leads to the release of fuel or oil that you were trying to keep contained in the first place. Building a bigger secondary containment system, that is sized to hold extra rainwater and fluid, is the primary method for preventing these problems. Drains, covers, and pumps to remove water before it can mix with the oil and fuel, will also work. Finally, advanced equipment for separating mixed oil and water may be necessary for secondary containment systems where there’s a high risk of rainwater contamination.
2. Quick Removal
The EPA regulations regarding hazardous waste containment specify that any leaked or spilled oil and fuel must be cleaned up as soon as possible. There’s no specific time frame specified, but having fluids standing in the containment area during an inspection is a problem. Letting spills stand for more than a few hours poses a few different risks, including:
- Chemicals seeping out through an unknown crack or porous area
- Corrosion caused by the breakdown or long-term exposure of chemicals
- Evaporation that creates hazardous fumes around the containment area
- Reduced volume for future leaks, increasing the risk of a discharge into the surrounding environment.
3. Seep Resistance
The EPA regulations don’t specify what materials or design you must use for secondary containment on the oil field. Instead, they say you must use liquid-tight materials that are free from cracks and other openings that could create leaks. This means you need a seep resistant material that is highly impermeable to liquids. Many lining materials start out that way after manufacturing only to develop tiny cracks and holes after exposure to reactive oil and gas products. Stick with liners that can handle heat, wear and tear, UV exposure, and petroleum products, in order to secure the difficult environment of an open oil field.
Unlike with materials and design specifications, the EPA does get fairly specific when it comes to capacity. The containment system must be able to hold 100% of the largest container being protected or 10% of the entire combined storage volume. When working on an open oilfield, each section in need of containment can contain millions of gallons of combined stored volume. Make sure to check calculations multiple times before assuming you’re properly sizing a containment system. Oversizing should only be used to compensate for rainwater and other runoff since it significantly increases the costs of everything from lining to installation.
5. Sloped for Drainage
A leaking tank or container that’s releasing oil and fuel must not become surrounded by the leaked liquid. This can accelerate corrosion and other issues, increasing the risk of a larger leak occurring in the future. For smaller tanks and refueling areas, a sloped floor or grate is usually enough. Secondary containment basins for large storage tanks and entire oil field areas will likely need active sump pump protection. These pumps switch on when a leak is detected to ensure the oil or fuel never gets a chance to build up around the container.
Of course, these five considerations are just the basic structure of any good containment system. Only an experienced engineer can help nail down the specifics of a secondary containment design for a facility as large as an oil field or fuel processing plant. Turn to us here at BTL Liners for support with the lining process from start to finish. Our reliable liners will give you peace of mind that your secondary containment system will work as designed when the unexpected happens.