EK can extract even very low concentrations of contaminants from various mediums, and is ideal for clay applications, which are characterised by low hydraulic conductivity and high particle surface charges.

This technology has found application in the rehabilitation of sites contaminated with a wide range of hazardous substances. The technology has been applied in areas such as:

• Dewatering and consolidation
• Removal of heavy metals and radionuclides
• Prevention of groundwater pollution

A schematic representation of electrokinetic mechanisms created in soil

Testing the EK parameters of a material. The test set-up and progress of salt through the medium

By using EK, high-risk areas such as processing sites can be kept free of contaminants and tailings can be stabilised through dewatering.

Some of the advantages of using EK for remediation are:

• Operation of the installed cell enhances safety by limiting exposure of personnel to inherent hazards.
• EK can be applied in some heap leaching operations to mitigate channel flow.
• EK is flexible and resilient to low permeability challenges.
• Toxic substances can be treated, extracted or rendered immobile while the process plant is operational
• EK is cost and energy effective.

In dewatering applications, the cost of implementing and operating the EK system can be offset against improved water utilisation and increasing the lifespan of the current TSF.

EK is often the best available technology (BAT) for in situ rehabilitation of areas contaminated with hazardous substances. Environmental impact is reduced by continuous rehabilitation of affected areas throughout the life of a mine. Consequently the cost of mine closure is reduced.

The power source used to drive the 30 m electrokinetic installation