Industrial Wastewater Indirect Discharges in Integrated Pollution Prevention and Control Perspective: A Case Study of Prague

Wastewater discharge is one of the sources of environmental pollution. Wastewater pollution originates, inter alia, in industrial wastewater. After treatment, industrial wastewater can be discharged directly into the receiving water body or indirectly into a sewerage network terminated by the concluding stage of wastewater treatment. In the Czech Republic, indirect wastewater discharges are obeyed by the contractual relationship between the wastewater producer and the sewerage network operator. General limits for indirectly discharged wastewater are not set by any national legislation. The aim of this paper is a description of industrial wastewater discharged into the municipal sewerage system in Prague and possibilities of setting limits for installations undertaking the industrial activities listed in Annex I of the Integrated Prevention Act. The study showed that 72% of installations discharge industrial wastewater indirectly. The majority are energy plants that produce boiler blowdown wastewater. More than 80% of wastewater from studied installations is treated by one central wastewater treatment plant. The studied installations are equipped with a wastewater neutralization unit. However, despite the existence of the legislative framework to propose limits for studied installations, only two installations covered by BAT conclusions with relevant BAT-AELs for indirect discharges to the receiving water body were determined. Generally, a small percentage of installations can be limited by an integrated permit due to an inconsistent approach to the issue of indirect discharges from installations under the scope of the Integrated Prevention Act.