Environmental Engineering Reference
In-Depth Information
world's drinking water.
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Add man-made pollution, including agri-
culture and irrigation runoff, to the naturally occurring kind, and
the groundwater poisoning issue intensifi es. According to the EPA,
NPS is now recognized as the primary threat to water quality in the
United States.
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Consider California, a state many see as an environmental
leader. “There is no such thing as a clean, pristine aquifer system in
California,” says Richard Atwater, of Inland Empire Utilities Agency
in Southern California. “Geologically, we have naturally occurring
arsenic in the groundwater wells and a variety of man-made pol-
lution, like nitrate pollution, from the legacy of agriculture or the
aerospace industry in Southern California during World War II and
the Vietnam War. We have solvents and different chemicals used by
aerospace in rocket manufacturing. Every one of our groundwater
basins or aquifers in Southern California either has a Superfund
site or a signifi cant number of contaminated wells.”
We'll talk more in the next chapter about what comes out of
your tap besides water. For now, let's just say that it can include
everything from arsenic to selenium to pesticides, boron, molyb-
denum, uranium, MTBE, methane, chromium-6, and much, much
more. In March 2009, some homeowners in Fort Lupton, Colorado,
had to cope with fl ammable water coming out of their faucets.
Other locales around the country have experienced similar situa-
tions. Some suspect the problems could be related to natural gas
exploration, drilling, and wells in the areas that possibly contami-
nate the private wells.
Natural Pollutants
In states like New Hampshire, New Jersey, and Maine, groundwater
wells can be contaminated with too-high concentrations of naturally
occurring arsenic.
Selenium is another contaminant found in groundwater in
parts of California and South Dakota. A naturally occurring, nor-
mally trace element common in certain types of rock, selenium is
vital to humans and animals in small quantities but can be toxic
in higher concentrations. Often the selenium concentrations are
