Regional Scales of Groundwater Quality Parameters and their Dependence on Geology and Land Use

A central problem in remediation is the estimation of the extent of the pollution. This is usually done on the basis of point measurements performed at selected locations. These data are then used to assess values at unobserved locations. There are a large number of methods available for this purpose. The purpose of this contribution is to present some geostatistical methods which can efficiently use additional information for the estimation. The additional information can include qualitative knowledge about the soil structure or other contamination related information but also physical considerations (flow modelling). Another frequent problem is the treatment of data below the detection limit. Indicator transformations and probability maps do offer a correct consideration of these values. The methodology is demonstrated on a larger regional scale, on groundwater pollution data. The reason for this is that the large number of available data, and the possible comparison with natural components in the groundwater can be better used for statistical comparison and illustration of the methodology. With effectively no modifications the same estimation techniques can also be applied to small scale problems, usually occurring in remediation.