A note from Bob Mesibov: The picture isn't 100% clear but I think I can see a pointy "tail". That would make it the introduced Portugese millipede, Ommatoiulus moreleti. None of the native SE Australian "juliform" millipedes have pointed, projecting "tails". See https://www.polydesmida.info/tasmanianmultipedes/milli-jul-key.html and https://www.polydesmida.info/millipedesofaustralia/key2orders.html