The project will be carried out in different phases. In a first phase, the first HGBcell using biostimulation will be installed and operated in an area with CAH concentrations which will allow the use of biostimulation. Next, the results of the first HGBcell will be used to calibrate the existing groundwater model. The calibrated groundwater model will then be used to adjust (if necessary) the dimension of the HGBcell and to determine locations for the other HGBcells. Consequently, HGBcells using biostimulation will be installed in deeper groundwater layers and in other areas with comparable CAH concentrations.