Changes in the groundwater quality of the main useful aquifer as a result of the hazard of nitrates from agricultural sources

Abstract

Abstract The article presents the results of research, conducted in central Poland, where agriculture is the dominant type of land use. This activity is considered as a common potential hazard to groundwater quality because of the use of nitrate fertilizers, especially for small groundwater intakes used for the purpose of rural water supply. For this kind of intake seven scenarios of groundwater quality hazard were elaborated based on the results of the hydrodynamic modelling research in this area including the following: calculation of volume and time of leakage through the aquitard formations to the main useful aquifer, verification of the indirect protection zone and definition of the size of the well capture zone. The scenarios considered the current groundwater quality hazard as well as changes in agricultural land use or changes in fertilizer doses needed to decrease groundwater hazard by nitrates in the intake.