According to the type of groundwater and soil contamination, we develop tailor-made process layouts for mechanical, biological and/or chemical groundwater rehabilitation plants. Prior to planning of remediation schemes we utilize two and three-dimensional mathemati- cal models for simulating groundwater flow and transportation. Strategies for complex in situ and on site treatment plants may be combined with individual groundwater, surface water or surface-to-air remediation technologies aiming at good treatment results and minimized plant operation cost.