Most shafts in Vic have collapsed in on themselves, due to the old timers undermining the base of there shaft. The shafts that stood the test of time were in harder ground however a lot have been back filled by parks for liability reasons. I was speaking to a seasoned prospector about shafting on my last trip (two weeks ago) his friend is into shafts, that is all he does. He sinks one a month pulls 3oz on average. I think this story might be like a fishing tale. Generally the success of most diggings in Vic was 2 in 10. Two out of ten shafts sunk were super rich. One out ten paid and the rest ? Well, try again. Be very wary of any shafts you find in wet ground! They are death traps. Many a miner lost there lives in wet ground. Fastest burials in history. If you want to get into shafts think about shoring the walls, have a sound exit plan, look at gold leads where the sinking was less than 16 feet. There is plenty of gold in the pillars.
Sorry I got off track a little, are you chasing mines or alluvial shafts?
I know of plenty of old mines that can be accessed if your looking for adventure.