Mineral Resources Hydrogeology – Pt Nusa Halmahera Minerals

Valenza Engineering assisted Mining One and Pt Nusa Halmahera Minerals managing a complex dewatering program for an underground gold mine. A deep hydrothermal groundwater system causes 80ºC water inflows into the mine workings, requiring high temperature compliant techniques. The existing sump pumping system being at capacity, our client required the design and implementation of a new deep bore pumping system to allow mining to safely continue.

Managing the water balance is important to operating within safe environmental limits

Our team developed a conceptual hydrogeological model, and built a 3D groundwater model to investigate different dewatering options and design pumping infrastructure with the optimum number, size and positioning for safe and efficient management of the groundwater at the site. The model was calibrated and revised as pumps were installed to incorporate new information and analyse the impact of dewatering.

Modelling the system using leapfrog

With frequent and detailed communication we were able to provide the client with information and training throughout the project to assist the forward planning process and tailor the modelling requirements to the mine development. With a project in such a remote location, this communication was vital; slow delivery times meant equipment needed to be ordered significantly in advance.