Engineering firm Thuthuka Group has been awarded the contract for all of the on-site water reticulation for the new Elands Platinum mine near Brits in the North West province.

Both process and potable water will be delivered to the mine. Project manager Francois le Roux said that the initial focus is to install the major reticulation pipe systems between terminal points (some 6 kilometers of 200mm to 350mm nominal bore (NB) pipe work). Construction of the many pump stations at Elands Platinum are currently under way.

The last phase of the project sees the construction of the Water Treatment Plant (WTP) and the Sewage Treatment Plant (STP). The WTP produces 300 m³/h process water to Elands' quality specification and 150 m³/h potable water to SANS 241 Class 1 water. The average dry weather flow design capacity of the Sewage Plant is 45 m³/h.

Elands Platinum obtained an abstraction permit from Department of Water Affairs and Forestry to abstract water from one of the Hartbeespoort irrigation canals. Le Roux indicated that around 400 m³/h water will be abstracted and pumped via a 4,5 kilometer transfer line to an open quarry on the Elands site.

The quarry acts as water sink and equalisation volume for all the mine water. From the quarry (and through about 650 m of 350 mm NB pipe), 450 m³/h water is transferred with pumps on a floating barge to the WTP.

On the plant a set of control valves spit the flow into a 300 m³/h and 150 m³/h stream and from there into the two separate treatment trains.

After treatment, process water is transferred to the mine's process water dam located near the mine's concentrating plant. Potable water is transferred to a 500-m³ storage tank.

"Most of the process water ends up on the tailings dam. This water is recovered via penstocks, clarified in a settler and recovered back into the process water system by pumping it back to the process water dam," said Le Roux.

If the dam nears a 100 % capacity, the control circuit repositions a set of control valves to allow the recovered tailings dam water into the quarry. Should the quarry level be at or near its pre-defined maximum level, the control system reduces the water abstracted from the irrigation canal.

The final effluent from the STP is also pumped to the quarry to recycle this source of water back into the system.