Do you have a private well?
About 42 million people in the U.S. get their drinking
water from household wells, springs, cisterns, and
streams (instead of getting piped water supplied by
public water systems). Although the federal
government does not supervise private wells, most
states have requirements for home well installation.
Gasoline is one of many pollution threats to the
ground water that supplies your well. If you are a
private well owner, the best way to make sure your
drinking water is safe is to test it! More importantly, if
your water supply is clean now, you can take steps to
protect it from pollution in the future (see the section,
How can you protect your drinking water from
pollution risks?, below).
What is MTBE?
MTBE (methyl tertiary-butyl ether) is a chemical added
to gasoline to increase octane. Its use began in the
1970’s to replace lead in gasoline. After 1995, many
metropolitan areas of the country with smog problems
also added MTBE to gasoline because it helps to
reduce harmful emissions from automobile exhaust.
Adding MTBE to gas has been one way to meet EPA’s
Why is MTBE a
drinking water concern?
Gasoline and heating oil travel through pipelines and
are also distributed by truck to above ground and
underground storage tanks. Underground storage tank
leaks and spills provide major sources of MTBE.
In addition, people store gasoline in cars, boats,
planes, lawn mowers, chain saws, generators, and off-
road vehicles. Therefore, farm and residential releases,
car accidents, spills, boats, and storm water runoff also
release gasoline into the environment.
MTBE moves quickly through soil, dissolves easily in
water, and takes longer to break down than some
Could MTBE be in your water?
The US Geological Survey has found MTBE in ground
water in 24 states, though gasoline with MTBE poses a
risk wherever it is used, transported or stored. The
USGS has found MTBE in water roughly five times
more often and at higher concentrations in areas of the
country where M