F-Leach tool assesses leaching risk of pollutants to groundwater and predicts soil quality

Point sources of pollution pose a risk for contamination of groundwater and surface water with a long-lasting impact. F-Leach is a software tool developed for the Flemish government that allows to make a risk assessment and identify which sites are potentially sensitive to the leaching of pollutants to groundwater.

  • A process-based model considering sorption in soil and degradation
  • Adheres source-path-receptor logic
  • Fast and robust calculations for the impact on groundwater
  • Predicts the soil quality evolution
  • F-Leach is the official tool for soil pollutant leaching risks in Flanders since 2010

Point source pollution

To identify the long-term contamination risks of point source pollution for groundwater and surface water, it is important to be able to quantify the seepage of solutes from the unsaturated zone.

F-Leach’ process-based model offers reliable calculations and makes it possible to recognise which sites are potentially sensitive to the leaching of pollutants to groundwater.



F-Leach offers a structured screening methodology consisting of different steps with a first step based on limited information. Each subsequent step demands more site-specific information, enabling a more sophisticated calculation of groundwater contamination risks to be applied.


Tiered approach

In a first tier the software calculates a threshold value for each site based on limited information, in order to exclude non-sensitive sites at an early stage.

If sites are not excluded in this first tier, the software performs a source-path-receptor analysis calculating the concentration in groundwater, considering the distance to groundwater and the attenuation of the concentration during transport to groundwater.

This allows the user to assess the concentration levels that can be expected in groundwater and the timeframe of the leaching process.


Variety of substances

F-LEACH currently deals with the solute transport of substances such as metals, PAHs, chlorinated solvents and aromatic compounds. Other substances can also be assessed if the physico-chemical properties are known.