Australian Potash Ltd. has started a trial evaporation pond development program at Lake Wells Sulphate of Potash Project in WA to gauge optimum commercial-scale pond construction techniques. The program will include more than 10 square kilometers of evaporation ponds, which will support precipitation of halite while boosting potassium and sulphate concentrations in the brine. Low permeability clay layer near the surface at the side is an excellent barrier to mitigate for vertical seepage of brine and the Australian potash miner seeks to integrate the overlying ‘Kopai’ dunes as pond embankments.
The company’s Chief Executive Matt Shackleton commented that “prior to the construction of full-scale commercial evaporation ponds, we need to confirm the most economically and technically optimal construction method for the pond walls – stage I ponds will be approximately 10 square kilometres in area making data gathered in this program vital to future development.” Mr. Shackleton also added that “we know we can take advantage of the surface clay layer to seal the bottom of the ponds – what we are assessing is which is the best wall construction technique to seal the walls of the ponds. We call these on-playa trial ponds, as they are built unlined on the lake surface.”
This program is one of the final two field programs currently underway to finalize the feasibility study data set – the other is the long-term test-pumping program on production wells. The Lake Wells Potash project is a flagship project of Australian Potash. Located approximately 480 kilometres northeast of the Eastern Goldfields centre of Kalgoorlie, the project is being explored for the premium fertilizer mineral Sulphate of Potash (SOP) contained within the lake brines.