Green remediation by facilitating industrial water use and heat surplus in the Port of Rotterdam

In the Port of Rotterdam the long-term presence of various industrial activities has resulted in soil and groundwater contamination. This contamination is substantial, complex and is usually not limited to one particular site but affects (ground)water systems at a regional scale. This being the case, site-specific approaches are neither effective nor cost efficient. In these cases it is better to develop an integral approach at megasite level, in which risk management scenarios are combined and measures are prioritized. The natural resilience of the soil and groundwater system will help significantly in reducing the risk of contaminated groundwater, if managed properly. In the EU WELCOME project an integrated management strategy (IMS) has been developed and later on successfully applied at the Port of Rotterdam. The implementation has revealed that a significant cost-reduction of up to 40% can be achieved in comparison to a site by site remediation approach, if measures are considered following a risk based approach on megasite scale. Active remediation efforts will still be conducted within the framework of the Integrated Management Strategy in order to manage the risk of still present contaminations. Conventional remediation techniques need energy and produce CO2 which has raised doubts about the overall sustainability of these techniques. The introduction of green remediation approaches can significantly boost the sustainability of Area Management of Contamination. For megasites like the Port of Rotterdam the key to this ambition lies in the combination of several goals for energy and water. For the Port of Rotterdam it is possible to effectively combine industrial water use and the industrial heat surplus with the remediation of contaminated groundwater. By using the groundwater for cooling purposes and storing (part of) the heat surplus underground (Aquifer Thermal Energy Storage, or ATES), biological remediation can be stimulated under certain conditions. This will lead to both an improvement of the groundwater quality and a reduction of energy use and CO2 emissions.