Mobility and sorption assessment of selected pesticides in alluvial aquifer.

The objective of the paper was to use transport model of selected pesticides (carbendazim, acetamiprid and imidacloprid) in determination of linear sorption coefficients in alluvial aquifer. For constructing transport model, results of a field experiment at the location of Kovin-Dubovac drainage system in Serbia were used in order to set hydraulic parameters (hydraulic conductivity, aquifer layer thickness of the observed area, effective porosity etc.). The field experiment consisted of a tracer test during which concentrations of non-reactive tracer (Cl-) and selected pesticides (carbendazim, acetamiprid and imidacloprid) were monitored. For better characterization of hydraulic parameters, a pumping test was conducted at the observed well and results were used in designing transport model. Simulation model was constructed with Lizza groundwater flow software and W.O.D.A. (Well Outline and Design Aid) solver. Obtained linear sorption coefficients in the sand and gravel water-bearing layer were 0.14 mL g-1 for carbendazim and 0.11 mL g-1 for acetamiprid and imidacloprid. Results from this study are a unique insight into mobility of observed pesticides in the alluvial groundwater in natural conditions and can be used in contamination assessment for drinking water wells.