Groundwater contamination by Non-Aqueous Phase Liquids (NAPL)

Groundwater is a significant global resource, comprising 96% of the Earth's unfrozen freshwater. Groundwater resources are estimated to provide 36% of potable water, 42% of water for irrigation, and 24% of direct industrial water supply globally. About 75% of Europe depends on GW for water supply. Non-Aqueous Phase Liquids (NAPLs) are soil and groundwater contaminations, which remain undissolved or hardly dissolved in water. Physically and chemically, dissimilar fluids form interfaces among liquids and gas that prevent fluid mixing, and thus fluid flow in porous media is conceptualized as immiscible. Organic liquid contaminants such as petroleum oil, gasoline, or diesel fuel are frequent NAPL contaminations. Investigating, evaluating, and remediating the sites contaminated by NAPL is a challenging task. Exposure to even a small amount of pollution causes health and ecological risks to the environment. NAPLs are common soil and groundwater contamination in industrial countries. Remediation of contaminated sites by NAPLs is difficult and expensive, as NAPs are a long-term source of vapor, groundwater, and soil contamination in the subsurface zone.