Contamination of source waters can result in poor-quality drinking water, loss of a water supply, high cleanup costs, high costs for alternative water supplies and/or potential health problems. Some examples include:

• A leaking underground storage tank released gasoline into the aquifer. A nearby well had to be abandoned because of contamination of the town's drinking water supply;
• A city well had to be abandoned because of chemical contamination originating from a nearby wood treatment facility;
• A municipal authority was forced to install costly treatment devices when a migrating plume of dry cleaner fluid contaminated the water system's most productive well; and
• A small town's primary source of drinking water was shut down for nearly a year as a precautionary measure after a large leak in a gasoline pipeline occurred.