Australian mining jobs, operating machinery, or low level management  

I am seeking information about the availability of jobs, and potential income in the mining industry in Australia. I currently own and operate my own small business in New Zealand. I have been doing this for the past seven years and I'm now considering a change.
Before buying this business, I spent about 20 years working in quarries in NZ. I worked in hard rock, limestone and alluvial gravel quarries in that time. My experience included the operation and maintenance of dump trucks, bulldozers, processing plant, air track drill rigs, hydraulic excavators, front end loaders etc. I spent about 5 years as an assistant manager in a greywacke quarry and during this time was largely responsible for the drilling and blasting. I then spent seven years as a quarry manager in an alluvial quarry, and during this time assisted in locating a new resource and the ensuing land use consent process to open a new quarry.
I hold a New Zealand "A" Grade quarry managers certificate and a NZ Institute Of Quarrying diploma.