Double Wall Storage Tanks for Safe, Compliant Chemical Containment — No External Secondary Containment Needed Let's be honest—storing bulk chemicals comes with serious responsibility. A single leak isn't just a mess; it's a potential safety hazard, a costly cleanup, and a compliance nightmare. For decades, the "solution" was to build a massive, expensive concrete dike or containment basin. But that's a permanent, space-hogging, and costly hassle. There's a much smarter, simpler way....
Welcome to the modern solution: the double wall tank. Think of it as a complete "tank-within-a-tank" system, brilliantly engineered to provide its own secondary containment right out of the box.
If you're asking, "Is a double wall tank considered secondary containment?" The answer is an emphatic yes. Our dual containment tanks are specifically designed to meet or exceed federal EPA 40CFR-264.193 regulations. The outer tank is built to hold 110% to 120% of the inner tank's volume, giving you a complete, spill-proof storage system in a single unit. It's instant compliance and total peace of mind, all without a single bag of concrete.
We offer a massive selection of these double wall plastic tanks in capacities from 35-gallon day tanks to 12,500-gallon bulk units. With options in High-Density Linear Polyethylene (HDLPE) and Cross-linked Polyethylene (XLPE), you can find the perfect tank rated for even the most aggressive chemicals.
Applications for Secure, Spill-Proof Storage
When a leak is not an option, a dual containment tank is the only answer. These systems are trusted by professionals across every major industry to provide compliant, leak-proof storage. Here’s a look at where they truly shine:
Aggressive & Hazardous Chemical Storage
This is their primary purpose. They are built for storing corrosive liquids like sulfuric acid, sodium hydroxide, and sodium hypochlorite (bleach), as well as chemicals used in plating, surface finishing, and energy facilities.
Why? We offer tanks with heavy-duty 1.9 specific gravity ratings and specialized XLPE (Cross-linked Polyethylene) resin. The outer shell provides total peace of mind, ensuring that even in a worst-case scenario, hazardous materials are safely contained.
Water & Wastewater Treatment
These tanks are the standard for municipal and industrial treatment plants. They securely hold water treatment chemicals, polymers, flocculants, and also contain wastewater, leachate, and RO reject water.
Why? The fully enclosed "tank-in-a-tank" design is critical here. It prevents rain, snow, and debris from entering the containment area, which protects chemical purity and stops the containment from overflowing with rainwater—a common failure point for open-dike systems.
Agriculture & Municipal Services
This is the new standard for bulk liquid fertilizer and agricultural chemical storage. It’s also the perfect solution for brine, calcium chloride, urea solutions, and other liquid deicing agents.
Why? A double wall tank protects your valuable product from leaks, but more importantly, it prevents the costly environmental contamination of soil and groundwater, ensuring you meet all local and federal regulations.
Industrial Processing & Dosing Systems
The dual wall plastic tanks are a core component in many manufacturing processes. They're used as non-pressurized chemical mixing tanks, neutralization tanks for pH adjustment, day tanks, and for handling byproducts in food processing plants.
Why? The tank-within-a-tank design saves an incredible amount of valuable floor space compared to building a separate concrete basin, making plant and process line design much more efficient and cost-effective.
Fleet & Automotive Fluids
This is the safest, cleanest way to store Diesel Exhaust Fluid (DEF).
Why? Our high-grade double wall poly tanks will never rust or corrode like steel tanks can. This protects the sensitive purity of DEF (which can be ruined by rust) and ensures you have a compliant, reliable storage solution for your fleet.
Environmental & Site Management
Ideal for facilities that need to manage pollutants, such as stormwater runoff holding, leachate collection, or containment at liquid distribution and transloading sites.
Why? A dual containment tank provides a verifiable, engineered containment solution that satisfies regulators and demonstrates your facility's commitment to environmental protection.
Why Shop Double Wall Storage Tanks from Tank Depot?
You're here because you need a storage solution that is safe, compliant, and built to last. We get it. Here’s why you can be confident in getting your secondary containment unit from us.
Instant EPA Compliance
This is the number one reason. Our two-walled tanks are engineered to satisfy EPA 40CFR-264.193 for secondary containment right out of the box. You get 110-120% built-in containment, allowing you to skip the massive cost, time, and headache of building a separate concrete dike.
Engineered for the Harshest Environments
These tanks are built for real-world, outdoor use. All materials are UV-stabilized for long-term service in direct sunlight. They also feature molded-in tie-down lugs designed to interface with optional restraint systems, providing certified resistance for seismic zones and 150 mph wind loads.
Unmatched Chemical
We offer a full range of material options, including High-Density Linear Polyethylene (HDLPE) and specialized Cross-linked Polyethylene (XLPE). This means you can get a tank specifically rated for the most corrosive chemicals—like sulfuric acid or sodium hypochlorite—with heavy-duty specific gravity ratings up to 1.9.
Get a Complete, Customized Solution
We provide the accessories to complete your system. Our team can help you add OSHA-compliant ladder kits (in steel or fiberglass) and a full range of optional fittings, including flanged outlets, vent assemblies, and fill/draw pipe kits.
Smarter Design for Easier Use
Our tanks feature innovative options like the UFO (Unified Fitting Outlet), which allows for simple, secure bottom discharge through both the inner and outer tank walls, eliminating the need for complex top-draw pumps.
Factory Tested, Site-Ready
One failure is one too many. That's why every single double wall tank we sell is leak-tested before it leaves the factory. It arrives at your site certified, secure, and ready for service.
Get Compliant Storage, Delivered Countrywide
Managing a chemical storage site?
The single smartest investment you can make in your facility's safety, compliance, and efficiency is an all-in-one dual containment tank. It's not just a product; it's a fully engineered, factory-tested, and site-ready system. You get certified compliance and total peace of mind from the day it arrives.
Stop managing risk. Eliminate it.
Browse our complete catalogue of the best double wall tanks below to find the exact, compliant solution your operation demands.
