Here is a link to the Government Fact sheet on...

Here is a link to the Government Fact sheet on RSPT.

http://www.deewr.gov.au/Department/Documents/Files/10_Fact_sheet_Resource_Profit_Tax_Final.pdf

Note on page 3 it says:
"The RSPT will apply to super profits made from all non‐renewable resources on or after 1 July 2012 at a rate
of 40 per cent. RSPT liabilities will be deductible with RSPT refunds being assessable for income tax
purposes."

This indicates to me that RSPT Liabilities (amounts payable) will be deductible for Income Tax purposes, meaning that Income Tax of 28% will only be payable on any excess profit above the RSPT.

If I have interpreted this correctly, the absolute maximum rate of tax will therefore be 40% and the situation will not be as bad as I originally feared.