Jeths R2012-12-122012-12-121990-08-31http://hdl.handle.net/10029/261806Abstract niet beschikbaarThe Dutch groundwater quality monitoring network includes 380 monitoring points. The frequency of sampling is once a year. The objectives of the network are: - to make an inventory of the present quality in relation to soil use, type of soil and hydrogeological conditions ; - to distinguish long term changes in quality ; - to provide data for quality control and groundwater management ; - to indicate the extent quality of human influence on groundwater quality. This report gives the results of analysis in 1989 from 40 monitoring points in the province of Zuid- Holland.82 pnl13Report2012-12-12