Volatile organic compounds (VOCs), which are widely used in the manufacture of many products including refrigerants, plastics, adhesives, paints, and petroleum products, have been detected in about one-third of the wells sampled by the National Water-Quality Assessment (NAWQA) Program of the USGS.
- Chloroform and other trihalomethanes, the most commonly detected compounds, were found in about 9 percent of the sampled wells.
- Solvents, particularly chlorinated solvents, were found in about 8 percent of sampled wells.
VOCs predominantly occur in urban areas, often in mixtures; specifically, 2 or more compounds were found in about one quarter of the sampled urban wells.
Learn More: Volatile Organic Compounds in the Nation’s Ground Water and Drinking-Water Supply Wells
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- FAQ
How important is groundwater?
Groundwater, which is in aquifers below the surface of the Earth, is one of the Nation's most important natural resources. Groundwater is the source of about 37 percent of the water that county and city water departments supply to households and businesses (public supply). It provides drinking water for more than 90 percent of the rural population who do not get their water delivered to them from...
Where can I find detailed sampling methods for surface water and groundwater?
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If the ground filters water, is groundwater always clean?
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Where can I get my well water tested?
Some counties offer free well water testing, so check with your county first. If they don't, use this EPA website to find a list of state-certified laboratories in your area that do water testing, or contact your county or state health department or your State Certification Officer for assistance. Prices will vary depending on the laboratory and the test(s), but most people consider the cost to be...
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What can cause our water to have an earthy odor or to smell like rotten eggs?
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Where can I find information about bottled water?
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