Bodemwassen

Bodemwassen, in English known as soil washing, is a remediation technique used to treat contaminated soil by separating pollutants from the soil matrix through water-based processes. The method aims to reduce the concentration of contaminants so that the treated soil can be reused or disposed of more safely, while the contaminants are concentrated in a liquid or sludge stream for further treatment.

The typical workflow involves characterizing the site, excavating the contaminated soil (often ex-situ), and processing it through washing, sieving, and physical separation. The soil is crushed and passed through screens to separate particle sizes, then washed with water or a water-based solution (sometimes with surfactants or pH adjustment) to mobilize contaminants. The resulting material is separated into a cleaned soil fraction and a secondary waste stream (slurry or sediment) containing most of the contaminants. The liquid waste is treated or disposed of, and the cleaned soil may be returned to the site or used as backfill if it meets applicable standards.

Bodemwassen is most effective for fine-grained soils and contaminants that are movable with washing, such as certain heavy metals, hydrocarbons, and some chlorinated organics. It is less suitable for soils where contaminants are strongly bound to mineral matrices or for technologies requiring in-situ treatment. Advantages include substantial volume reduction of contaminated material and potential on-site or near-site treatment. Disadvantages include high water use, generation of secondary waste, energy and equipment needs, and variable effectiveness depending on contaminant type and soil characteristics. Regulatory approvals and proper waste handling are essential components of project planning.