You are visiting the web site of the EPSCI Program at the U.S. Dept. of
Energy's Ames Laboratory, Ames, IA
A
Ablation
The rapid reduction of soil particles by means of a focused
laser.
Act of God
An unanticipated grave natural disaster or other natural
phenomenon
of an exceptional, inevitable, and irresistible character, the
effects of which could not have been prevented or avoided by the
exercise of due care or foresight.
Action Level
(1) The exposure level at which OSHA regulations to protect
employees take effect, e.g., workplace air analysis, employee
training, medical monitoring, and record keeping. Exposure at or
above the action level is termed "occupational exposure".
(2)
Regulatory level recommenced by EPA for enforcement by FDA and
USDA
when pesticide residues occur in food or feed commodities for
reasons
other than the direct application of the pesticide. As opposed to
"tolerances" which are established for residues occurring as a direct
result of proper usage, action levels are set for inadvertent
residues resulting from previous legal use or accidental
contamination.
(3) In the Superfund program, the existence of a
contaminant concentration in the environment high enough to
warrant
action or trigger a response under SARA and the National Oil and
Hazardous Substances Contingency Plan. The term can be used
similarly in other regulatory programs.
Acute
Occurring over a short period of time; used to describe brief
exposures and effects which appear promptly after exposure.
Acute exposure
A single exposure to a toxic substance which results in severe
biological harm or death. Acute exposures are usually characterized
as lasting no longer than a day.
Alpha particle
The least penetrating type of radiation usually not harmful to
life.
Alternative method
Any method of sampling and analyzing for an air pollutant which
is
not a reference method or an equivalent method but which has been
demonstrated to the Administrator's satisfaction to produce, in
specific cases, results adequate for his determination of
compliance.
Alternative technology
Proven wastewater treatment processes and techniques which
provide
for the reclaiming and reuse of water, productivity recycle
wastewater constituents or otherwise eliminate the discharge of
pollutants, or recover energy. Specifically, alternative technology
includes land application of effluent and sludge; aquifer recharge;
aquaculture; direct reuse (non-potable); horticulture; revegetation
of disturbed land; containment ponds; sludge composting and drying
prior to land application; self-sustaining incineration; methane
recovery; co-disposal of sludge and solid waste and individual and
on-site systems.
Please e-mail comments to: epsciwebkeeper@ameslab.gov.
Last modified: 1 April 2002 by dave eckels
ESC Glossary: etd/library/glossary/glossaryA.html