Reconsideration at Field Scale of the Relationship between Hydraulic Conductivity and Porosity. The Case of a Sandy Aquifer in South Italy,

To describe flow or transport phenomena in porous media, relations between aquifer hydraulic conductivity and effective porositycan prove useful, avoiding the need to perform expensive and time consuming measurements. The practical applications generallyrequire the determination of this parameter at field scale, while most of the empirical and semiempirical formulas, based on grainsize analysis and allowing determination of the hydraulic conductivity fromthe porosity, are related to the laboratory scale and thusare not representative of the aquifer volumes to which one refers.Therefore, following the grain size distribution methodology, anew experimental relation between hydraulic conductivity and effective porosity, representative of aquifer volumes at field scale, isgiven for a confined aquifer.The experimental values used to determine this law were obtained for both parameters using only fieldmeasurements methods. The experimental results found, also if in the strict sense valid only for the investigated aquifer, can giveuseful suggestions for other alluvial aquifers with analogous characteristics of grain-size distribution. Limited to the investigatedrange, a useful comparison with the best known empirical formulas based on grain size analysis was carried out.The experimentaldata allowed also investigation of the existence of a scaling behaviour for both parameters considered.