Project Background

Flinders Mines needed groundwater investigations for mine dewatering systems, requiring operational water supplies, environmental approvals support, hydraulic modeling and flood protection measures.

Advisian was commissioned by Flinders Mines Limited (FMS) to undertake groundwater investigations during the Pre-Feasibility Phase of its Pilbara Iron Ore Project (PIOP). The PIOP Project site is located approximately 70 km northwest of Tom Price, in the Pilbara Region of Western Australia. The study area is situated within the Central Hamersley Channel Iron Deposit (CID) Province. The PIOP is a large scale, high quality iron ore mine comprising of five main deposits; Delta, Champion, Eagle, Ajax and Blackjack. The Delta, Champion and Eagle deposits are were the focus of this investigation.

Our Services

Our consultants performed a data gap assessment of existing exploration data and refined the available hydrogeological information during the Pre-Feasibility Phase of the PIOP. The results were then used to develop and implement a groundwater exploration program to define accurately the dewatering requirements for the project and to develop a water supply strategy to meet the project water demands.

An airborne electromagnetic survey program was developed in association with GPX Surveys, and implemented in May 2011. GPX also performed interpretation of geophysical and drill hole datasets in the eastern drainage channels of Flinders Mines Blacksmith tenement in the central Pilbara. The aim of the program was to model and gain information on the structure and lithology of the area, targeting palaeochannels following the current drainage network.

The data acquired from the airborne survey along with historical ground gravity, Airborne Frequency Domain EM, geophysical and geological logs and profile interpretations, was used to develop 3D models and target potentially high yielding zones in the Delta, Champion and Eagle deposits. The groundwater exploration targeted these higher yielding zones.

The field program involved drilling, construction and testing of 15 monitoring bores, 3 test production bores and conversion of 36 existing exploration holes to monitoring bores. The monitoring bores were equipped with automatic loggers to monitor baseline groundwater levels and water samples were also collected to establish baseline groundwater quality.

Results

Our consultants used results of the field program to develop FEFLOW groundwater models for the mine areas. The models were used to develop dewatering system requirements, dewatering infrastructure designs, power requirements and CAPEX/OPEX estimates.

Stream and rainfall gauging sites were also established and the results compared with the groundwater monitoring data to calibrate the groundwater models, confirm the surface-groundwater interactions and validate the conceptual hydrogeological model.

Acid and metal generating capacity of proposed iron ore waste rock dumps and tailings storage facilities (TSFs) was assessed from CIDs.

Water balance modeling was used to assess the potential project water supply sources to meet the project water demands and develop management strategies for potential excess mine dewater.

We also prepared 5C license applications and Operating Strategies and continue to provide ongoing support to relevant regulatory approvals.