Historically, industries were in harbour areas of cities for easy access to transportation of resources. Today, transforming former industrial areas into living spaces has become attractive business. However, this transformation has often been challenged by high levels of soil contamination caused by the industrial use. Remediation measures are mandatory to ensure the public safety in the redeveloped areas. Detailed information about the contaminant type, distribution and transport mechanisms is required to address the contamination issues. This paper presents a workflow for investigations assisting decision making for construction work in redeveloped industrial areas. The workflow is applied to Horsens harbour (Denmark). In this area, renovation of the harbour walls introduces the risk of spreading of phenol contamination to planned construction areas. The study demonstrates how detailed information about the geology and hydrology at the site allows for scenario modelling of contaminant transport, guiding remediation efforts and aiding decision makers in developing the harbour area.