Background
SGME undertook a geochemical assessment to determine the source of site contamination. Using a risk-based approach, a conceptual cover design was then developed. The mine is an underground polymetallic operation located north-west of Mount Isa within the Gunpowder District of North West Queensland.
Objective
A contaminant source investigation identified mobilisation and leaching of waste rock as a primary contributor to surface water exceedances found during scheduled water monitoring. The waste rock on site includes potentially acid forming (PAF) waste rock for which proper management is required to minimise leaching of contaminants into the receiving environment. A possible rehabilitation option is a cover design that limits infiltration, thereby reducing seepage potential.
Solution
SGME was enlisted to contribute to program design and to conduct waste rock characterisation which is a crucial step in comprehending environmental risks. Field tests involved handheld x-ray fluorescence, pH and electrical conductivity being tested to screen samples for acid mine drainage (AMD), neutral mine drainage and saline drainage, and to confirm whether waste rock is the primary concern for surface water quality. Subsequent laboratory testing affirmed the issues of contaminant mobilisation and leaching.
In the subsequent project phase, SGME used humidity cells to mimic environmental conditions for evaluations of AMD concentrations in seepage and potential risks.
Transitioning to the final phase, SGME facilitated a multiple accounts analysis workshop. This analytical process evaluated six potential cover options for WRD rehabilitation which culminated in the identification of a preferred cover design. The analysis fostered informed decision-making, encouraged value management initiatives and led to feasible engineering solutions that ensured development of a reliable and sustainable waste management strategy.
Engaging SGME for field testing results in precise data collection and real-time insights. We will deliver our services in a way that is cost-effective, customised and aligned with regulatory requirements to enable informed decisions, support operational efficiency and maximise savings for your project.
