Numerical models are used to simulate the movements of contaminants in the aquatic environment. Such models may assess:

• water currents and mixing within lakes and rivers
• temperature affects
• assimilative capacity and lake eutrophication
• water/sediment exchange processes
• mixing and burial within sediment
• degradation/formation by biological or chemical processes
• uptake by aquatic biota
• transfer to terrestrial biota
• transfer to humans

Contaminant transport modelling is often undertaken in environmental pathways analyses and ecological and human health risk assessments.