2. Hydrogeological boreholes and wells database and its use on regional rock permeability determination

In the archive of the State Geological Institute of Dionyz Stur, a collection of some 18,000 manuscript records on hydrogeological surveys have been gradually built up. Since 1970's, records on reported hydrogeological boreholes and wells were gradually abstracted into unified paper formats. With the start of the new millennium, a digital borehole database was created. Having necessary data for doing this, regional values of transmissivity coefficient T and hydraulic conductivity K data could be derived from specific capacity data on pumping tests from boreholes and wells. Using complex re-interpretation process, eliminating influences of differently performed pumping tests and taking into account hydraulic resistivities, both of wells and aquifers, specific capacity data could serve as relatively good source for hydraulic properties estimation. These were performed for 106 different aquifer types, using data from 16,239 individual pumping tests on boreholes. Comparison of the resulting regional distribution of hydraulic properties with frequently applied classification scales for these parameters shows that mean regional values can be found in relatively narrow intervals, while individual boreholes and well can differ from each other in a broad spectrum of values (authors)