Ann: Cooper Basin Project Update , page-30

Pixie,
the water is in a closed system, like that in the radiator of the car.
Up one hole, through the power plant, via high pressure pipes, back down the next hole, through the rock.
The rock underground is enveloped by impermeable rocks, trapping any water in the fractures under pressure.
In fact there has been water trapped in the naturally occurring fractures for millions of years, which makes granites like these a safe place to bury Synrock (trapped nuclear waste). Of course that won't fly past head in the ground greenies. Oops that's going to open a can of worms...