The modern, non-stop wastewater purification plant from 'Heros Sluiskil' has a tank park with a capacity of 1,250,000 m³. The wastewater is biologically purified using nitrification/denitrification technology. After purification and sand filtration, the effluent is indirectly discharged into the Westerschelde. 'Heros Sluiskil' focuses on industrial wastewater that, for example, originates from the food industry, recreation, agriculture and waste sector. Moreover, a new pre-processing plant also enables more heavily polluted water flows to be received for processing.