Landfarming is a biological treatment technique for contaminated soil. It involves spreading a layer of contaminated soil over an area of land and enriching it with nutrients to encourage the growth of micro-organisms that break down the contaminants.
The landfarming process begins by assessing soil contamination levels and selecting a suitable site for the technique. Once the site has been chosen, a layer of contaminated soil is spread over the surface, and nutrients are added to encourage the growth of natural micro-organisms.
The micro-organisms feed on the nutrients and contaminants in the soil, breaking them down and converting them into less toxic substances. This process generally takes several months or even years, depending on the quantity of contaminants present in the soil.
As contaminants are broken down, the soil layer is turned over to expose new surfaces to microorganisms. This method can be repeated several times until soil contamination levels are acceptable for safe use.
Landfarming is effective for treating soil contaminated by mineral oils, pesticides from agricultural pollution, heavy metals and other toxic chemicals. It is also less costly than other contaminated soil treatment techniques, such asincineration or soil extraction.
However, landfarming can take time to achieve complete results, and may not be effective in treating volatile contaminants that can evaporate into the air. In addition, landfarming requires regular monitoring to ensure that contaminants do not reappear in the soil.
For on-site remediation, other treatment methods can be used, such as anaerobic biostimulation, bioventing, composting, containment, thermal desorption, excavation, vacuum extraction, incineration, chemical washing, chemical oxidation, phytomanagement, pyrolysis, chemical reduction, stabilization, stripping, biological treatment or granulometric sorting.