The Snyder Industries 4000 Gallon ASTM XLPE Double Wall Tank (SKU 5610000N40) is built for operators who need real secondary containment without running a separate berm or basin. It nests a primary tank inside an outer wall, so a leak from the inner vessel is caught in the interstitial space instead of reaching your pad. The tank holds 4,000 gallons, stands 178 inches tall on a 102 x 102 inch footprint, and is molded in natural white crosslinked polyethylene so you can read the liquid level through the wall. This is the Snyder double wall XLPE platform many buyers find searching for an "xlpe double wall tank" or "4000 double wall."
Will it work for your site
The wall is Crosslinked Linear Polyethylene (XLPE) carrying a 1.5 specific gravity rating, meaning it is engineered for liquids up to 1.5 times the density of water at full volume. Plan your pad and anchoring around real loaded weight, not gallons: 4,000 gallons of water alone weighs 33,360 lb, and at the tank's full 1.5 SG rating the contents can reach 50,040 lb. The 102 x 102 inch footprint has to carry that load on a flat, engineered base. Factory fittings on this unit include a flange, an 18-inch PE threaded and vented opening, and a manway with 15-inch access. That 15-inch access governs whether a person or probe can get inside for the interstitial inspection this tank is built around, so confirm placement and clearance against the technical drawing on this page before you set your plumbing.
Sizing it correctly
Crosslinked double wall tanks are rated by the density of what you store, so the SG rating is the spec that protects you. Run your stored liquid's specific gravity and your usable volume through our Tank Sizing Calculator and the Tank Sizing Guide before ordering. Because this is an ASTM D1998 vessel, freeboard and thermal expansion matter to the volume you can actually use; our guide on Snyder Captor double-wall freeboard sizing per ASTM D1998 walks through it. For cold-climate fire-water and reservoir duty, see our notes on fire-water reservoir design and freeze protection.
The mistake to avoid
Do not assume the outer wall lets you ignore the SG rating. The 1.5 SG number is the design ceiling for the primary tank at full volume; storing a denser liquid, or overfilling past the rated freeboard, stresses the vessel where failures actually start. Wall thickness at the vapor-saturated headspace is where premature failures originate, not on the liquid-wetted side a quick inspection sees; our breakdown of tank wall thickness at the headspace explains why. One more detail buyers miss: the 18-inch PE threaded and vented opening and the flange are connection points, not finished plumbing. Match your bulkhead fittings, gaskets, and flange hardware to your stored liquid, not just to the tank's 1.5 SG rating. If you are specifying interstitial integrity testing for a buried or steel-adjacent installation, our reference on cathodic disbondment testing for interstitial spaces covers the methodology.
This tank ships LTL freight from the nearest Snyder plant, quoted live to your ZIP rather than bundled into the list price. Snyder produces this double wall platform at more than one ship-point, including Lincoln, NE, so your freight is routed from whichever plant serves your delivery state best; eastern buyers in particular can see a materially different LTL number depending on origin. Get a number before you commit using our Freight Cost Estimator, or call 866-418-1777 and we will work your delivery, offload, and access details directly. Have your delivery ZIP and any site access limits ready and we will get you an accurate LTL quote on this 4,000 gallon double wall tank.
