A fissile solution storage vessel has been designed and analyzed which consists of a central column surrounded by intersecting arms resembling a tree with many branches. The intersecting arms are reduced at their junction with the central column to minimize the amount of surface area of an arm (which contains most of the stored liquid) in contact with the central column. Critical experiments and calculations done at Rocky Flats have shown that this area of intersection is very reactive. If this area of intersection is reduced, it is possible to increase the numbers and diameters of the arms, thus allowing more fissile material to be stored in this geometry. This method of solution storage is cost competitive with the use of borosilicate-raschig-ring-filled tanks for the storage of large quantities of fissile materials for special applications. Several such applications are storage of solutions corrosive to glass raschig rings, solutions where inorganic plutonium polymer (PuO2 × H2O) buildup is possible and plutonium solutions in excess of 220-g Pu/liter. The tree tank can safely store 400-g Pu/liter, whereas the limiting concentration for raschig ring tanks is 220-g Pu/liter. For this particular application, the initial cost per kilogram for Pu storage is ∼$53/kg for the tree versus ∼$ 56/kg for the raschig ring tank. If one considers the cost of maintenance of the two methods over a period of five to ten years, the tree tank is competitive over an even wider range of applications.