Dam Straight: Why are Tailings Storage Facilities so important?

Tailings is a by-product of the metals and minerals recovery process. Tailings are created when mined ore is crushed and finely ground in a milling process, and is a thick liquid made up of fine mineral particles and water.

The tailings are typically pumped to engineered storage facilities called Tailings Storage Facilities, or TSFs, which are effectively large dams. As the sandy residue of tailings gradually drains, it dries out becoming compact and enabling the facility to be rehabilitated.

To prevent potential environmental impacts from the fine material and residual pollutants, water from within the TSF must be contained and treated before release.  Once captured, the water can be reused to offset freshwater use.

At Mount Isa Mines, tailings are produced by the mills at the Zinc Lead and Copper Concentrators.  The tailings are pumped to large a TSF 3.9km south-west of Mount Isa City and covering an area of 1,500 hectares.

The Mount Isa Mines TSF is a purpose-built, rigorously engineered structure which is designed, constructed and operated to safeguard lives and prevent impacts to human health and safety, the environment, communities, cultural heritage and infrastructure. Our focus is on strong technical management and review, governance oversight, stakeholder engagement, transparency and continuous improvement.

The TSF is managed in line with the Global Industry Standard for Tailings Management (GISTM), which sets international best practice for social, environment and tailings management. It is also managed in accordance with the Australian National Commission of Large Dams (ANCOLD) and Queensland regulations.

One of our commitments as part of good practice for TSFs is to share information about our TSFs with the community and increase public awareness. Over the last six months, we have engaged directly with our closest neighbours, Traditional Owners, Mount Isa City Council, the Mount Isa Water Board and Regulators regarding the management of the Mount Isa Mines TSF and emergency response planning.

As with other potential risks at our operations, a key element in the safe, responsible and sustainable management of our Mount Isa Mines TSFs is having an Emergency Response Plan. 

A flood event from the TSF is highly unlikely, but it is important to have an Emergency Response Plan to set out how we will respond and communicate with emergency services and the community in the unlikely occurrence of an event to ensure people's safety and minimise impacts.

We have worked closely with key stakeholders, including the Local and District Disaster Management Groups (LDMG and DDMG) and Mount Isa City Council, to develop an effective Emergency Response Plan for the TSF.  

The LDMG and DDMG are responsible for planning and coordinating responses to a range of natural disaster events, accidents, and other emergencies in the community. They are comprised of local and state agencies, including emergency service organisations.

Part of emergency response planning is to test the plan by running mock exercises. We do this annually with the LDMG and DDMG along with other key community stakeholders to ensure it remains current and effective.