The effect of plant-soil treatment plant on the groundwater quality

Wrocław University of Environmental and Life Sciences, Institute of Environmental Engineering, pl. Grunwaldzki 24, 50-363 Wrocław, Poland

^* Corresponding author: katarzyna.paweska@upwr.edu.pl

Abstract

The paper presents the impact assessment of the plant-soil treatment plant on the groundwater quality. The physicochemical composition of groundwater was analysed. The samples were collected form the piezometer network located in the irrigated area and around it. Water quality tests were carried out in 2014 with the frequency of the month. Changes in the physicochemical composition of groundwater were determined with reference to quality of domestic wastewater used for irrigation. The obtained results were also referred to groundwater parameters limits before the facility’s operation started. As a result of many years of exploitation the groundwater quality under the irrigated area has changed. The boundary of individual segments of wastewater treatment plant is clearly marked by the change in concentrations of the observed pollution indicators. The highest values of organic matter expressed by BOD and COD were observed in the groundwater the I segment (respectively 6.9 gO₂·m^-3 and 66.2 gO₂·m^-3). This was the results of a change in the irrigation regime. As the result of irrigation, an increase of nitrate (V) and nitrate (III) was also observed in comparison to their pre-operational values. Plant-soil treatment plant prove high effectiveness of work. However, due to their significant impact on the groundwater quality their operating should be gradually reduced.