In Australia, at the BHP Billiton Mitsubishi Alliance (BMA) Asset, increasing climatic variability has resulted in alternating periods of low rainfall, followed by flooding.
Water quality release thresholds, based on estimated ecosystem responses applied by the State Regulator, were restricting BMA’s ability to discharge excess water during these times of extreme rainfall, causing inundation of mine pits for extended periods.
In order to gain a greater understanding of, and better plan for the impacts of, mine water discharge, BMA developed the Aquatic Ecosystem Health Research Program in partnership with the University of Queensland’s Sustainable Minerals Institute and the Central Queensland University Centre for Environmental Management.
Over three years and two wet seasons, the program involved the collection of more than 150,000 data points to monitor and measure the effects of mine water releases in the receiving environment. This work demonstrated the impact of mine water releases was far lower than previously thought, allowing BMA to work with regulators to achieve release conditions that more accurately reflect known impacts.