Alcoa - Water use: Questions

1189. Hon Lynn MacLaren to the Minister for Agriculture and Food representing the Minister for Water:

(1) I refer to Alcoa’s use of water from the Wellington Dam and from the Harvey Waroona region, and ask if there is a direct pipeline between Wellington Dam and Wagerup?
(2) Is there a desalination plant to make this water suitable for Alcoa’s purpose?
(3) If these two items of infrastructure are in place, who built and paid for them and when?
(4) If it exists, who pays for the running costs and maintenance of this infrastructure?
(5) Does the water from Wellington Dam go directly to Alcoa’s residue storage area (RSA)?
(6) If the saline Wellington Dam water is fed directly to Wagerup’s RSA for dust suppression, what is the effect of run off on the groundwater in that area?
(7) Does saline water from Wellington Dam in fact go into the Harvey Dam to be diluted, with the equivalent amount of water taken from the Harvey Dam for use at the Wagerup RSA?
(8) If saline water from Wellington Dam goes into Harvey Dam in an exchange arrangement, what is the effect on the quality of the water in the Harvey Dam?
(9) What is the quantity of water taken annually from the Wellington Dam for Alcoa?
(10) How much do Alcoa pay for this Wellington Dam water?

Hon Ken Baston replied:

(1) No
(2) The Department of Water is not aware as to whether Alcoa has a desalination plant at Wagerup.
(3) Not applicable
(4) Not applicable
(5) No
(6) Not applicable
(7) Yes. Water from Wellington Dam water is gravity fed to a holding excavation and then pumped to Harvey Dam. The transfer of this water is managed by Harvey Water utilising their infrastructure.
(8) Harvey Water is responsible for monitoring of salinity in Harvey Dam.
(9) Not applicable
(10) Not applicable