oa Comparison of MRS and Pumping Tests in Denmark

In Denmark hydrogeophysical mapping is performed intensively in accordance with the Danish Government's environmental plans of ensuring high quality drinking water supply based solely on naturally clean and chemically untreated groundwater. This national Danish groundwater mapping is performed by the Danish Ministry of the Environment as a part of the Act of Environmental Goals, which stipulates extensive groundwater mapping of particularly valuable groundwater abstraction areas comprising 40 % of Denmark. Since 2006 efforts have been made to implement the Magnetic Resonance Sounding method (MRS) in the Danish national groundwater mapping in accordance with the conventional requirements for geophysical methods in Denmark. from 2006 to 2010 approximately 160 MRS soundings have been performed in Denmark in different hydrogeological environments. Each campaign has been performed with a specific purpose and agenda as a part of the general groundwater mapping, and the method has been proven to improve the hydrogeological characterisation from geophysical surface measurements in Denmark. the MRS results from different Danish hydrogeological conditions are verified by comparing numerous MRS and pumping tests. When these comparisons are performed with attention on the investigated volume in each specific case, very good correlation is obtained. these comparisons of MRS and pumping tests have lead to the determination of MRS calibration coefficients from different Danish hydrogeological conditions. MRS calibration is essential for quantitative use of MRS transmissivities. A tendency of increasing calibration coefficients with increasing transmissivity and aquifer grain size is revealed, however overall only little dispersion around one average value is observed.