NITRATE AND SULFATE ISOTOPES IN THE GROUNDWATER OF THE SANDY HALTERN FORMATION (GERMANY) TO INVESTIGATE NITRATE REDUCTION PROCESSES

摘要

With a thickness of up to 300 m, the sandy aquifer of the Haltern Formation is one of the most important drinking water resources in north-west Germany (NRW). Six water works extract around 53 Mio. m~3 a year of groundwater and deliver drinking water to around 4 Mio. costumers. Five of these catchment areas were investigated in this study. Due to the intensive agricultural land use a strong nitrate input into the shallow groundwater occurs and leads to significantly increasing nitrate concentrations in the shallow groundwater.