Australian Potash Limited updated flow modelling outlines the potential for increased production from brine at the Lake Wells Sulphate of Potash Project (LSOP). Updating the hydrogeological flow model with this data indicates the potential to increase the annual production of sulphate of potash (SOP) from the LSOP from 120,000 tonnes per annum (tpa) shown in the FEED study to 135,000tpa (an increase of 15,000tpa or 12.5%). Additional improvements realised in the recent modelling also indicate that 89 supply bores will be suitable for life-of-mine (LOM) operation, whereas the original FEED development model had 172 bores over the LOM, a 48% reduction in installed bores. In the Company's Definitive Feasibility Study (DFS) released in August 20191, SOP production from brine abstraction was projected to be 100,000tpa, resulting in a Probable Reserve of 3.6Mt# (utilising approx. 20% of the
in-situ Measured Resource). An additional 50,000tpa was forecast in that DFS to be produced through the addition and conversion of Muriate of Potash (MOP) to SOP. The brine abstraction rate was optimised through the FEED study, leading to optimised SOP output of 120,000tpa. Through the DFS, external consultants AQ2 prepared a hydrogeological model for the proposed development of the LSOP. This model has been updated regularly with actual data generated in the field. Short term pump testing allows the reconciliation of the modelled early-time flow rate at each bore to the actual early-time flow rate likely to be recorded in operations. The inclusion of the data from the test pumping of the bores completed to date2 in the hydrogeological model, reconciles positively and indicates the potential to increase the annual SOP production from brine abstraction to 135,000tpa (+15,000tpa/12.5%). A further improvement derived from the updated flow model is seen in the reduction in the number of bores required to produce the necessary brine flow. Where the FEED model indicated a required 79 bores at startup, expanding to 172 bores over the life of the LSOP, the current model revises the required bores down to only 89 bores over the life of mine. The potential cost savings over the life of the mine from the reduction in bores required may be substantial. Along with the reduction in bore number, the updated flow model predicts higher grade and a longer production profile. The implications to the pond network, harvest ponds, and processing plant are being thoroughly considered in light of the improved flow model.