This maybe of interest to fellow Aussies, a website with a list of popular burial sites for Military stuff (fact and fiction)
http://www.ozatwar.com/ozatwar/dumped.htm
Includes the tale of a tunnel at Bandiana that was supposedly used for vehicle storage, until it was emptied and everything crushed. (I have never heard of this one, and I am only 20 kms away)
Tunnels in the Dandenongs and other areas
Advert for the bonfire for 550 Kittyhawk/spitfires to be burnt at Oakey, 1947.
At least you will be able to see if there is anything of interest in your area.
Rich.