Snyder Industries Snyder 8700Gal HDLPE Double Wall Chemical Tank 1.9 SG Opaque

The opaque shell, and a sibling list that leaves the double wall family

This part number is unusual on its own sheet, and the family list is where you see it. Most contained tanks this size are grouped with three or four part numbers in the same shell at different resins and colours. This one is grouped with two tanks that are not contained at all: SII-53000600N42, an 8000 gallon vertical liquid storage tank, and SII-5330000N30, a 10500 gallon vertical chemical storage tank. Neither of those is described on the sheet as a double wall or containment tank, and this page will not describe them that way either. So the comparison the sheet actually invites is the one worth making: a contained 8700 against two larger or similar single wall verticals, which is the real decision most buyers at this scale are making anyway. The contained tank brings the secondary containment inside the purchase, at the tank boundary, with nothing to pour, coat, drain or inspect as a separate structure. The single wall tanks are cheaper to buy and lighter to set, and they put the containment obligation back onto the site, where it becomes a berm with its own drawings and its own maintenance. Both answers are legitimate and the right one depends on the site, not the tank. The second thing this sheet gives you is the shell itself: opaque, rated at a specific gravity of 1.9, which is the line a dense liquid has to be checked against before anything else on the page matters. An opaque shell is chosen where light on the contents is the problem and the level is taken by instrument rather than by eye, which at 197 inches of height is how it is taken regardless. Under it, the foundation is the real project. A 142 inch base carrying 72,558 pounds of water, or up to 137,860 pounds of contents at the rating, wants a designed, surveyed, cured pour, flat and continuous and wider than the tank, because a rotationally molded floor bears on every part of what it touches and nothing else, and on a contained tank the outer shell is the part doing the standing. Before anything is ordered, run 8700 gallons against your delivery size and turnover in the tank sizing calculator, and take the working reserve and the freeboard a warming liquid needs from the tank sizing guide.

An 8700 gallon contained tank against two single wall verticals

Three rows, three genuinely different propositions, and the weights tell the story. This contained tank is 6,000 pounds empty. The 8000 gallon SII-53000600N42 is 2,300 pounds on a 120 inch base at 186 inches tall, and the 10500 gallon SII-5330000N30 is 4,000 pounds on this same 142 inch base at 169 inches tall. Read those side by side and the second wall is visible in the weight column: a contained tank is a tank inside a tank and it weighs and freights accordingly. Read them again for the site and a different picture appears. The 10500 gallon vertical holds more than this tank, on the same footprint, standing lower, at two thirds the empty weight, and it is rated at a specific gravity of 1.9 the same way this one is. If your site already has a compliant bermed pad with capacity to spare, that row is probably the better buy and we will say so plainly rather than sell you a wall you already own. If it does not, the arithmetic flips: a berm for 8700 gallons is a structure with drawings, a coating specification, a drain and a pump, an inspection regime and a maintenance budget, and this tank arrives with the containment answered at the tank boundary instead. The 8000 gallon vertical is the smallest and lightest of the three and the only one on a 120 inch base, which is the row to look at if pad width is the constraint. What none of the three publishes is a containment volume, an annulus dimension or an inner tank dimension, so no figure of that kind appears on this page; ask us and we will get it from Snyder in writing. Where the site obligation is the thing you are actually buying against, the boundary between the tank and the site plan is drawn in the Captor double wall compliance walkthrough.

Neighboring size a better fit? Every row links to its own page; freight to your ZIP is quoted on each, or call 866-418-1777.

One 18 inch threaded vented manway, and nothing else on the sheet

• The vent is the fitting this sheet gives you, and it is worth saying that plainly: one 18 inch threaded vented manway, and no other opening published. That vent is the whole breathing path for 8700 gallons. Unloading a tanker pushes that volume of air out; drawing the tank down pulls it back in. On a shell 197 inches tall, an obstructed vent is a wall problem, so it goes on the inspection list by name and it never gets capped against weather.
• Headspace: leave it. The vapour space above the liquid line is where a chemical tank works hardest, and a warming liquid needs room that a tank filled to the manway does not have. The freeboard logic is set out in the freeboard sizing guide, and on an 8700 gallon tank the gap between capacity and usable volume is measured in hundreds of gallons.
• Level: nobody eyeballs a level through an opaque shell 197 inches tall, so the gauge is part of the specification. It belongs through the manway rather than through a new penetration, and the choice between radar, ultrasonic, hydrostatic and magnetostrictive measurement in chemical service is worked through in the level gauge selection guide.
• Overfill protection: the release that actually happens at this scale happens with a hose connected. High level alarms, automatic cutoff and valve discipline are the layers that stop it, and the architecture for them is laid out in the spillover redundancy guide. On a contained tank they are what keeps the containment space empty and unused.
• Outlet and inlet: the sheet publishes neither, so neither appears here. Sizes, types and elevations are confirmed with us at order against Snyder's current documentation, before anything is cut.
• Access, limit, warranty and rating: an 18 inch manway reached by a designed platform and ladder; 120 F / 48 C; a 3 year warranty; and a specific gravity rating of 1.9 with 137,860 pounds given as the maximum contents against 72,558 pounds of water.

Nothing gets bolted, braced, drilled or hung on the outer shell that Snyder has not specified, and that rule is the difference between a contained tank and an expensive single wall tank. Pipes, valves, gauges, alarms, ladders and shade structures stand on their own steel; the first joint at the tank is flexible; the containment space carries no conduit, no penetrations and no rainwater. Keep the full circumference walkable and lit. Then treat that space as the instrument it is, with a torch, a written schedule and a named owner, because anything found standing in it is the cheapest warning an 8700 gallon installation will ever get.

Acid, hypochlorite and process chemistry at 8700 gallons

The liquids this size of contained tank is bought for are the ones where a release is the incident rather than the inconvenience, and the compatibility question is settled before the order, not after the first delivery. Start in our chemical compatibility database, and read the records for the chemistries most often asked about at this scale first: sulfuric acid, sodium hypochlorite, hydrochloric acid and peracetic acid. Bring us the actual liquid, its temperature at the inlet, the temperature it sits at, and what else shares the pad, and the part number, the fittings and the gasket materials get confirmed against Snyder's current documentation rather than assumed. Where these tanks go: bulk chemical storage feeding treatment or dosing at a municipal water or wastewater plant; primary storage at a mining, minerals or metals processing site; mill chemical supply at a pulp, paper or board plant; plating, anodising and finishing works; disinfection and oxidant storage at a large utility or food plant; blending and distribution terminals where one tank holds one product and has to answer for it alone. Two limits, said once each. Nothing on this sheet gives a containment volume, an annulus figure or an inner tank dimension, so this page states none, and we will get it from Snyder in writing when a permit needs it. And the service limit is 120 F / 48 C, for the liquid and for the tank, which takes anything arriving hotter out of scope.

Nebraska to the pad, oversize, at 6,000 pounds

Molded at Lincoln, Nebraska, this tank moves as an oversize load: class OVS on NMFC 156600, shipped 197 inches long by 142 inches wide by 142 inches high at 6,000 pounds. Twelve feet across and sixteen feet long is a permitted load with a planned route, and three tons of empty tank is a crane or a large telehandler with rigging chosen in advance. The freight cost estimator prices the lane to your ZIP, and the listed price is before freight. Get us involved in the logistics before the purchase order rather than after it: yard and gate width, overhead lines and limbs, the turn, the surface the truck and the lifting equipment will stand on, and where the tank can be laid down if the pad is not ready. The pad should be poured, cured, surveyed and accepted before the truck is booked, because nothing about a tank of this diameter is adjustable once it is standing. Inspect the whole shell, the base ring and the manway with the rigging crew while it is horizontal on the trailer. Then water-test in place, hold it, survey the foundation, and open the containment space and look into it before any product is ordered. Log the serial number off the shell against the foundation survey and the water-test record in one file, and the next twenty years of inspections will have something honest to compare against. Once it is full and holding, leave it alone for a day before the plumbing goes on; a settled tank is a quiet one.