Toxic Substances Hydrology Program
DNAPL (Dense Nonaqueous Phase Liquid) - "A DNAPL is one of a group of organic substances that are relatively insoluble in water and more dense than water. DNAPLs tend to sink vertically through sand and gravel aquifers to the underlying layer." - U.S. Environmental Protection Agency, 2010
DNAPL - "An acronym for denser-than-water nonaqueous-phase liquid -- an organic liquid, composed of one or more contaminants, that does not mix with water and is denser than water. The most common DNAPL contaminants in ground water are chlorinated solvents." - National Research Council, 1994
DNAPL - "Chlorinated solvents are more dense than water and are thus called dense NAPLs, or DNAPLs. Other DNAPLs include coal tars, which contain PAHs [polycyclic aromatic hydrocarbons], and transformer oil, which may include mixtures of PCBs [polychlorinated biphenyls]." - National Research Council, 1994
DNAPL - "Many of the halogenated hydrocarbons are characterized as dense nonaqueous-phase liquids (DNAPLs). Their densities exceed that of water, but they have lower viscosities. Their solubility in water is in the range of 100-500 mg/L." - Lesage and Jackson, 1992
Text in brackets ("[text]") are additions by the editor
USGS Information on DNAPLs
Other Information on DNAPLs
Lesage, S., and Jackson, R.E., 1992, Groundwater contamination and analysis at hazardous waste sites: Marcel Dekker, Inc., 552 p.
National Research Council, 1994, Alternatives for ground water cleanup: Washington, D.C., National Academy Press, 315 p.
U.S. Environmental Protection Agency, 2010, Waste and cleanup risk assessment glossary: U.S. Environmental Protection Agency, access date July, 27, 2010.