Abstract A container device (11) for the long-term storage of hazardous material F), particularly for use for the ultimate disposal of nuclear fuel, comprises a plurality of containment bodies (A, B, C, D), placed successively one with in the other. Each containment body comprises a casing wall and an upper and a lower end wall and has a compartment defined by these walls. The innermost containment body (A) holds the hazardous material and each of the other containment bodies B, C, D) contains a respective next inner containment body (A, B, C). Self-compacting concrete is used to fill the spaces between the containment bodies.