Hallo NamesTheir water losses would probably be 1. 15 tph...

Hallo Names

Their water losses would probably be 
1. 15 tph adhering loss to tailings
2. 3 tph adhering loss to con
3. 20 tph seepage on the tailings dam
4. Evaporation from all exposed water. This will be more in the summer

Those bores on site would have to go down to at least 60m otherwise if the pit gets to 61. Thatd the end of the water. The water table translates across for several hundred meters. Those bores only yield about 4000 litres per hour, so if they didn't have at least 10 bores operating they would have run into trouble.  Maybe they use a dewatering pump in the pit to supply water which takes a great load off the bores. My guess is they drowned that pump. They will live to see another day. Fortunately Cowan is very big but thy here is no doubt that the water table is creeping down and mining have to talk to plant all the time.

Good on ground management is needed