It is also argued that there are other ways to immobilize and secure plutonium so as to keep it safe from misuse, for example by mixing it with nuclear wastes (or of course leaving it in un-reprocessed spent fuel). Moreover, although it would generate energy from what would otherwise be wasted material, not only is this expensive, it is risky moving it around to reactors, since it is possible to use it for weapons production (it is easier to get at the plutonium in unused MOX fuel than in the fiercely radioactive spent fuel rods). Consequently, shipments have to be heavily guarded. Moreover, as with any other nuclear fuel, once used in a reactor, the highly active spent MOX fuel would have to be dealt with. But the crucial point is that the use of MOX fuel will only make a small dent in the plutonium stockpile, since this is growing all the time due to the continuance of reprocessing operations.