MOX FUEL confirmed in Plant #3 by Four Different Sources! http://theintelhub.com/2011/03/12/29810/

In the meantime, there have been suggestions that an incident at reactor 3 would inherently be more dangerous than at reactors 1 and 2 because it burns “mixed oxide fuel” (MOX) containing plutonium.Plutonium is produced during nuclear fission, so is present in all reactor cores – the longer the fuel has been there, the more plutonium will be present, up to about 1%.In some countries, spent fuel rods are re-processed and the plutonium set to one side.However, Japan – in an attempt to be more frugal with a valuable resource – has a programme that mixes the plutonium coming out of the re-processing facility back into new fuel rods that also contain uranium. This is MOX fuel.