An introduction to natural source zone depletion at LNAPL sites

Sources of hazardous chemicals in the subsurface may pose significant risks to human health and the environment. Of particular concern are light non-aqueous phase liquid (LNAPL) source zones that may contain considerable chemical mass, and pose potential risks via direct exposure to LNAPL, vapour migration / intrusion and dissolved-phase impact to controlled waters. Spills of hydrocarbon fuels and oils form the most common examples. Remediation of such sites requires effective source zone management to achieve successful outcomes.