Use Of Passive Sampling To Identify Organic Pollutants In Groundwater

The anthropogenic organic pollutants have been recognized as one of the important factors in environmental pollution. Strict legislation concerning the quality of drinking water in the EU requires the optimisation of analytical methods for organic pollutants. Commonly used monitoring systems usually only record pollutant concentrations at a specific point in time. Contrary passive samplers cover a long sampling period, integrating the pollutant concentration over time. This paper presents the application of passive sampling for a quality monitoring of organic contaminants in a coarse gravel aquifer Vrbanski plato which presents the main drinking water resource for Maribor, the second largest city in Slovenia. Passive sampling devices with granular activated carbon were applied in 15 observation wells and in the Drava River. In 9 monitoring points, passive samplers were applied at different depths of the saturated zone. Two sampling series covered the period of one year. In both series, 161/166 organic compounds were identified. The frequency and intensity of the identification has been determined for all the compounds. Forty detected organic compounds were classified in different pollutant groups with respect to their origin (urban source, agriculture or industry). An analysis of the presence of organic substances in the two periods, spring-summer and autumn–winter, was carried out. It showed that substances of agricultural origin were more present in the first period, while those of urban and industrial origin occurred more frequently in the second period. Passive sampling was proved as an appropriate tool for assessing aquifer contamination with organic compounds.