Contaminated soil stabilisation and immobilisation

Contaminated soil stabilisation is a remediation method that aims to reduce the mobility of pollutants and stop them reaching groundwater and the surrounding environment. Specially selected stabilising reagents and binders are injected into or mixed with the contaminated soil, where they interact with the contaminants and bind or immobilise them chemically. Different reagents and technical solutions can be used depending on the type of contamination and the soil properties. This approach reduces the long-term risk of contaminant leaching and migration, limiting their impact on the surrounding environment.

Capping is a remediation method for contaminated soil that isolates the contaminated area from the surrounding environment with a purpose-designed protective cover built over it, using geosynthetics, geomembranes, clay or suitably treated and stabilised on-site soil. The multi-layer containment system limits rainwater infiltration, reduces the risk of contaminant leaching and prevents direct contact with the contaminated material. This approach makes use of materials already on site and reduces the need to haul them away, providing long-term containment of the contamination.

Separating contaminated from clean soil means sorting soil by its degree of contamination, setting apart the contaminated soil from material that meets the quality requirements for uncontaminated soil. This gives a more accurate measure of the volume to be treated, reduces the amount of material to be hauled away and remediated, and makes better use of the soil already on site. Once separated, the contaminated soil goes for appropriate treatment, while the clean soil can be reused on site where regulations and project conditions allow.