Quantification of wastewater pollution load using potassium concentrations in karst spring discharges

Karst aquifers are highly vulnerable to pollution because of their unique and complex hydrogeological characteristics. Within this study, measured potassium concentrations in both, the Tanour and Rasoun spring discharges were employed to quantify the component of leaked wastewater either from local olive mills (Tanour spring) or domestic wastewater (Rasoun spring). Additionally, high-resolution physico-chemical data were recorded in both springs using an online automated telemetric station to investigate the response of the Tanour and Rasoun karst aquifer to pollution events. Measured potassium concentrations during spring discharge peaks were clearly indicative of pollution events in contrast to other ions and the Chloride-Bromide mass ratio. Undiluted leaked wastewater discharge rates from the olive mills and domestic wastewater during the whole monitoring period were estimated (mean/max) to be 6.4 m3/d and 93.6 m3/d for Tanour spring and 9.8 m3/d and 52.3 m3/d for Rasoun spring, respectively.