Environmental Enlightenment #112
By Ami Adini - April 14, 2005

This is a SHORT, LIGHT and SIMPLE newsletter. Its purpose is to rekindle in the initiated terminology they have once learned, and enlighten the uninitiated on terms they may have heard but never known the meaning of.

Where Did That Chemical Go

To dissipate in the environment means to disappear.

In these pictures, condensed vapor (clouds) is dissipating into thin air.

There are various mechanisms through which a chemical dissipates. It can break down to other chemicals, more toxic or less; it can scatter; it might adsorb to soil particles, it might evaporate, or it could be sucked out by plants or animals.

We measure the rate of dissipation by the half-life of the chemical in the environment.

Half-life is the time it takes for the chemical to be reduced by one-half of its original amount.

The lost 50% could be in the form of breakdown products.

This is why breakdown products must be identified and studied in the same way that the parent chemical is studied.

The dissipation of a chemical may be real, as in the breakdown of the parent chemical to its daughters.

The dissipation may not be real, as in the case when the chemical migrated from the source area elsewhere.

Hide'n'Seek

One must always remember that the fact that a chemical cannot be found does not mean it is not there.
Good testing will establish its whereabouts.

You can find past issues of our "Environmental Enlightenment" at www.amiadini.com: Wealth of information about environmental site assessments in the real estate transactions and issues concerning assessment and cleanup of contamination in the subsurface soil and groundwater.

Call me if you've got any questions. There are no obligations.

Ami Adini
Ami Adini & Associates, Inc.
Environmental Consultants
Underground Storage Tank Experts
323-913-4073; 323-667-2336 fax
mail@amiadini.com
www.amiadini.com

Ami Adini is a mechanical engineer, California Registered Environmental Assessor, Level II, and president of AMI ADINI & ASSOCIATES, INC. (AA&A), an environmental consulting firm specializing in all phases of environmental site assessments, rehabilitation of contaminated sites and upgrading of underground storage tank facilities. AA&A supplies practical solutions to environmental concerns using the highest standards of ethics and integrity while providing its clients with maximum return on their investments.