Kalgoorlie Waterbank Project - Geotechnical Investigation

Client: City of Kalgoorlie Boulder

Completed: In progress

The City of Kalgoorlie Boulder is looking to supply processing water to the Lynas Rare Earths facility, located approximately 5 kilometres west of Kalgoorlie. The existing recycled water supply falls short of meeting Lynas' increasing water demand due to expansions and anticipated growth. To bridge this gap, there is a critical need to develop new water sources and corresponding systems. These measures are essential not only for ensuring a sustainable water supply but also for accommodating the area's future development and expansion.

The City has provided Civil Sciences and Engineering with a conceptual plan detailing the different dams within the Water Bank project, which include Dam 1, Dam 2, Dam 3, and KBRC Dam. Previous geotechnical investigations have been carried out by the City. The current objective is to assess the rate of water seepage into Basin 2, particularly at depths greater than 7 meters. This assessment will encompass tasks such as evaluating the hydraulic conductivity of potentially permeable zones, especially around the rock contact level. Additionally, it involves measuring static groundwater levels at various new locations, supplementing the prior data. The ultimate goal is to provide an estimation of the aquifer yield into Basin 2. This estimation is crucial for assessing potential under-drainage requirements if the basin is to be lined, or for understanding potential ingress into the basin if it remains unlined. To achieve this evaluation, drilling will be conducted to reach a depth of 15 meters. 

The City has engaged Civil Sciences and Engineering to carry out a geotechnical investigation aimed at assessing the practicality of utilizing the suggested dams as an extra water source for Lynas. The investigation will encompass various activities, including a Constant Rate Pumping test, Step Rate pumping test, In-situ Permeability test, and Laboratory testing on samples collected from the site.