I guess it all depends on how GHD intend to produce the blue hydrogen. SMR or Hazer process.
Without some form of CDP running I dont see how they can choose the Hazer process.
On the other hand SMR is already a well established commercially proven cheap and viable method of producing hydrogen. The problem is that it produces about 10 tons of CO2 per ton of hydrogen produced.
Since, as the article says, they intend to pump the CO2 co-produced from the wells back into the reservoir, surely it wouldn't be such a big stretch to pump the CO2 co-produced from SMR downhole along with it, especially since the equipment to do so would already be in place ?
https://petroleumaustralia.com.au/projects/santos-looks-to-hydrogen-future-through-carbon-capture-and-storage/
(20min delay)