Water resources at remote mine sites
Australian mine sites, due to the scale of operations, where deposits are located and the noise involved in mining activities, are often located far from population centres. Additionally, the bulk of mine sites in Australia are in arid regions. The following map, from the Australian Mines Atlas, shows the locations of mineral resources, mines and processing centres. This map clearly shows that most mines are in the dry interior of Australia, far from major cities.
Given the arid environment these mines exist in, maintaining a reliable source of water can be a major issue for operators. Water carting, which can be used when a site is located close to major treatment plants or distribution networks, no longer becomes economically viable when the location is hundreds of kilometers from the nearest treated water source. Many mine sites therefore treat water for use onsite to ensure a reliable water source. However, there are a range of challenges that come with operating water treatment systems remotely.
Treating available water sources
Given mine sites are generally located in arid regions and water forms such an essential part of mine site operations, harnessing a reliable local water supply is essential for mine sites. Generally mine sites will have limited rain or surface water, although some will be located near rivers and streams, and will be forced to rely instead on groundwater and wastewater treatment.
Groundwater, particularly in the mineral rich deposits that mine sites are located on, will be high in heavy metals and will also often have high salinity. There exist a wide range of treatment systems which provide water for mining operations if the source water can provide the required volume. Wastewater is an underused asset across a lot of industrial applications as is improvements in water efficiency. All of these sources can be considered when considering a reliable water source for mine sites. All sources of water can be treated to any standard through combinations of physical, chemical and biological methods. An easy rule of thumb to consider is that the more that needs to be removed or added to water the more power, chemicals or time will be required.
Maintaining trained personnel
Another big issue with operating a water treatment system remotely, be it for a mine site or a remote community, is maintaining enough trained personnel who can operate the water treatment system. Maintaining sufficient staffing levels, usually through fly-in-fly-out workers, becomes difficult the more remote a mine site is. Due to this mines are becoming increasingly automated such as the Koodaideri deposit in the Hamersley basin and Newmont’s Boddington operation which now both maintain fleets of autonomous haul trucks.
Water treatment systems can also be automated through the addition of remote monitoring and control capabilities, to reduce the amount of personnel required to operate it. Once automated, the operation of the water treatment unit can be folded into other operations controlled from the remote operations centre. To take advantage of this solution uninterrupted internet connectivity is a must but coverage is improving across Australia particularly with the advent of satellite internet.
Encountering supply chain issues
Water treatment systems have a range of critical components which are essential for correct operation such as pumps, membranes, UV systems, valves and tanks. Additionally, a wide range of chemicals are used in water treatment including sodium hypochlorite, antiscalants and sodium hydroxide. Given the remote locations of many mine sites, supply chains can be extremely long, meaning remote water treatment units can go offline for long periods of time while replacement parts are sourced.
Mine sites can maintain critical spares onsite such as spare pumps and membranes, as well as maintain a well-documented chemical inventory to ensure that downtimes can be minimised. However, the best way to avoid supply chain issues is to design the system from the start with the installation location firmly in mind. For example, if chemicals are hard to source, then systems can be designed to operate chemical free. Alternatively if power fluctuations onsite are an issue then treatment units can be built around a UPS to ensure consistent power supply and hence consistent water production.
Maintaining a reliable power source
Traditionally remote mine sites use diesel or coal (particularly if already located onsite) to generate energy for mine operations. With the advent of climate change, less carbon intensive power sources are increasingly being used onsite. In April 2024, the Murrin Murrin nickel and cobalt mine in Leonora was granted $35 million from the federal government to bring renewables into their energy mix.
Renewable energy is very location dependent and renewable energy design for mine sites will have to take into account the local wind and solar assets and how the system will power mine operations when renewable assets are unavailable (i.e. grid/generator or battery backups). Horizon Power, which operates the electricity network in the Pilbara, is currently examining green hydrogen as an alternative to battery storage to bridge the gap in supply when the sun is not shining and the wind is not blowing.
Moerk Water are experts in maintaining water treatment systems in remote locations. To find out more about how we can support your mine site with a reliable source of water, contact Moerk Water today.
