grk more expensive than nuclear, page-27

There is a map of various basins in SA here:

http://www.pir.sa.gov.au/pages/petrol/prospectivity/interactive_basin_map/basinmap.htm:sectID=924&tempID=74

I suspect it is likely that areas where basis are will have a greater depth to any radiogenic granites with better insulation. This would lead to higher drilling costs to reach a particular target temperature. The area that GRK's tenements are on does not appear to be in one of these basins, which could be a reason for higher costs.