Spatial distribution of anthropogenic inputs into groundwater: a case study

摘要

At the Hardwald study site, Switzerland, 15million cubic metres per year of drinking water is being pumped. Chlorinated compounds, however, have been detected in the groundwater. Wepresent results from field sampling and lab analyses to determine thespatial distribution of chlorinated organic compounds, stable water isotopes (O-18 und D-2), major ions as well as selectedmicropollutants, which enter the groundwater by artificial recharge. Wedemonstrate that artificial groundwater recharge is essential forwater security and that the pumped groundwater has aclose chemical signature to that of the recharged river water. However, due to the heterogeneousinfiltration, Muschelkalk water from the regional flow system is mixed with therecently infiltrated water in the south-west.This interpretation is basedon the spatial distribution of chlorinated organic compounds, stable water isotopes, major ions as well as selected micropollutants.Despite the complex boundary conditions, the interaction betweenartificial recharge and pumping provides asecure drinking watersupply.