General Glossary

Hazard Ranking System Score. A
mathematical score given to each
Superfund site, used to set
priorities for cleanup of sites.
Also called an HRS score.

The bottom layer of lake water
during the summer months. The
water in the hypolimnion is denser
and much colder than the water in
the upper two layers.

Action taken to protect public
health or remove or continue an
obvious source of contamination
before a remedial investigation is
complete.

An electrically charged atom or
group of atoms.

A lot or property where worn-out
or discarded items, metal or other
scrap material is stored for
possible resale.

Topography characterized by
depressions without external
drainage, such as sinkholes,
underground caverns and solution
channels.

A process that involves study,
assessment of problems, and
decisions on how to maintain a
lake as a thriving ecosystem.