Algae -- the base of the lake's
food chain, it also produces
oxygen

The path and form taken by
contaminated ground water as it
moves from the source.

Pollution arising from a well-
defined origin, such as a
discharge from an industrial
plant.

A substance that pollutes air,
water or land.

The contamination of soil, water
or air by the discharge of
potentially harmful substances.

Equipment designed to reduce
pollution and the resulting
adverse environmental and health
effects from waste combustion or
disposal, or private or industrial
emissions. Filters are often used
to control emissions of particles,
and scrubbers can control
emissions of acidic gases, such as
sulfur dioxide and hydrogen
chloride.

Eliminating or reducing at the
source the use, generation or
release of toxic pollutants,
hazardous substances and hazardous
wastes.

A class of chemicals typically
formed by burning and common in
the environment. PAHs are also
common to petroleum products and
oil. Although most of these
compounds are harmless or mildly
toxic, some are carcinogenic.

Residential waste reused in
industrial process, such as
recycled newspapers used to
manufacture more newsprint.

Parts per billion. Ten ppb means
ten parts of a contaminant to one
billion parts of water.