Volatile organic compounds (VOCs) are produced in large volumes and are associated with a
myriad of products, such as plastics, adhesives, paints, gasoline, fumigants, refrigerants, and dry cleaning
fluids. Widespread and long-term use of VOCs and their ability to persist and migrate
in groundwater raise questions about possible adverse effects on the environment, including
drinking water quality. A long-term survey by the National Water-Quality Assessment Program
of the United States Geological Survey provides the most comprehensive national analysis to
date of the occurrence of VOCs in groundwater, based on results from sampling between 1985
and 2002. Among the major findings are that VOCs were detected in most aquifers throughout
the Nation, and were not limited to a few specific aquifers or regions. VOCs were not detected,
however, in many of the nearly 3,500 sampled wells; for example, about 80 percent had no
detections above a threshold of 0.2 part per billion. The most frequently detected VOCs were
chloroform, the solvents perchloroethene and trichloroethene, and the gasoline oxygenate methyl
tert-butyl ether; 13 of the 55 compounds included in the assessment were not detected at all. A
separate analysis of untreated groundwater samples from drinking water supply wells showed
that VOCs were detected in domestic well samples (14 percent) and public well samples (26
percent). Less than 3 percent of samples of groundwater from domestic and public wells had
concentrations greater than Federal drinking water standards. Includes 3 references, table.
| Edition : | Vol. - No. |
| Number of Pages : | 9 |
| Published : | 06/01/2007 |
