Low-Cost Spill Containment for Multiple IBC Tanks. Indoor and Outdoor Models available for 2, 3, 4 or 5 tanks. 100% polyethylene construction eliminates the potential for rust and corrosion. Each IBC tank sits on a low-profile Spill Pallet with a containment capacity of 75 gallons Expansion Tanks provide 65 gallons of additional capacity. Flow-through bulkhead fittings connect spill pallets and Expansion Tanks together, allowing spills to be channeled throughout the containment system containment capacity is thereby borrowed from adjacent spill pallets and Expansion Tanks. Meets SPCC and EPA Container Storage Regulation 40 CFR 264.175. Outdoor Models help meet new Stormwater Management Regulations NPDES, 40 CFR 122.26 (1999). (OUTDOOR) Unique roll top enclosures and swing-out doors allow convenient loading and unloading of IBC tanks. (OUTDOOR) Compartments are lockable for secure storage of hazardous materials. (OUTDOOR) Optional Extender Kits (Part# 9658) provide for the addition of another compartment. (1 tank per Extender Kit).