Non-aqueous phase liquid

Non-aqueous phase liquids or NAPLs are liquid solution contaminants that do not dissolve in or easily mix with water, like oil, gasoline and petroleum products.^[1]

NAPLs tend to contaminate soil and ground waters. Many common ground water contaminants such as chlorinated solvents and many petroleum products enter the subsurface in nonaqueous-phase solutions.^[2] They do not mix readily with water and therefore flow separately from ground water.^[3]

If the NAPL is denser than water, like trichloroethylene, it is called DNAPL and will tend to sink once it reaches the water table. If it is lighter, like gasoline, it is called LNAPL and will tend to float on the water table. ^[4] LNAPL penetrates below the water table like ice cubes in a glass of water. ^[5]

Notes

1. National Research Council, 1994
2. National Research Council, 1993
3. National Research Council, 1997
4. National Research Council, 1997
5. Interstate Regulatory Technology Council, 2015

See also

• DNAPL
• LNAPL

External links

• NAPL Definition from the USGS

References

• National Research Council, 1997, Innovations in ground water and soil cleanup--From concept to commercialization: Washington, D.C., National Academies Press, 310 p.
• National Research Council, 1994, Alternatives for ground water cleanup: Washington, D.C., National Academies Press, 315 p.
• National Research Council, 1993, In situ bioremediation--When does it work?: Washington, D.C., National Academies Press, 224 p.