Groundwater protection by soil improvements on a former sewage farm: assessing effects using coupled models

摘要

Because of contaminated soil horizons, e.g. with heavy metals, former sewage farm areas could be hazardous for groundwater and surface waters. To prevent a heavy metal breakthrough with negative consequences for the ecosystem, soil improvement by increasing the sorption capacity with the help of boulder clay seems to be possible. Consequently, a field test was carried out in 1998 at Berlin/Buch. Possible effects on the groundwater and surface water quality were estimated with the help of a coupled unsaturated/saturated water flow and transport model on a regional scale. Simulated scenarios show that contamination from areas with boulder clay covering takes place much slower and with lower concentrations due to an increased sorption capacity and water storage capacity in the unsaturated zone. Thus, results recommend this approach as useful and sustainable from an eco-hydrological point of view.