RECYCLING AND WASTE

During the desalination process, screening and pre-treatment of seawater will result in an amount of pre-treatment waste, including dissolved salts and organics, and small and large solids such as vegetation, sediment and micro-organisms.

Ferric sulphate — a common coagulant used in water treatment facilities around Australia and throughout the world — will be used in the pre-treatment process to make particles in the water join together so they can be filtered out.

The resulting waste will be a non-toxic substance that, if it weren’t for the salt content, could be reused as an additive for soil remediation. However, because of its salt content, it currently has no reuse and will be disposed of at a landfill that is appropriately licensed, based on final classification by the Victorian Environment Protection Authority.

In Australia there are currently three large desalination plants — in Perth, Sydney and on the Gold Coast. All have very similar operating systems to the Victorian plant. The resulting waste is generally classified for disposal to landfill, meaning it is disposed of in the same place as your kitchen scraps.

The amount of waste produced by the project, if operated at full capacity, will be about four to eight dry tonnes per day, which equates to around 20 to 40 wet tonnes per day or around two to three standard garbage trucks per day. This was assessed as part of the Environment Effects Statement (EES) for the project, which indicated about 23 to 63 wet tonnes per day. AquaSure’s process plant design has minimised this quantity to the lower bound range outlined in the EES.

Rain water will be collected from both the green roof and the covered treated water storage tanks. Other stormwater runoff from the site will be managed in accordance with the principles of Water Sensitive Urban Design.