Occurring over a short time [compare with chronic].
Agency for Toxic Substances and Disease Registry (ATSDR):
The principal federal public health agency involved with
hazardous waste issues, responsible for preventing or reducing
the harmful effects of exposure to hazardous substances on
human health and quality of life. ATSDR is part of the U.S.
Department of Health and Human Services.
Aquifer:
An underground formation composed of materials such as
sand, soil, or gravel that can store and/or supply groundwater
to wells and springs.
Chronic:
Occurring over a long time (more than 1 year) [compare with
acute].
Contaminant:
A substance that is either present in an environment where it
does not belong or is present at levels that might cause harmful
(adverse) health effects.
Dermal Contact:
Referring to the skin. For example, dermal absorption means
passing through the skin.
Exposure:
Contact with a substance by swallowing, breathing, or
touching the skin or eyes. Exposure may be short-term [acute
exposure], of intermediate duration, or long-term [chronic
exposure].
Groundwater:
Water beneath the earth's surface in the spaces between soil
particles and between rock surfaces [compare with surface
water].
Hazardous substance:
Any material that poses a threat to public health and/or the
environment. Typical hazardous substances are materials that
are toxic, corrosive, ignitable, explosive, or chemically
reactive.
Ingestion:
The act of swallowing something through eating, drinking, or
mouthing objects. A hazardous substance can enter the body
this way [see route of exposure].
Inhalation:
The act of breathing. A hazardous substance can enter the
body this way [see route of exposure].
Media:
Soil, water, air, plants, animals, or any other part of the
environment that can contain contaminants.
Model Toxics Control Act (MTCA):
The hazardous waste cleanup law for Washington State.
Monitoring wells:
Special wells drilled at locations on or off a hazardous waste
site so water can be sampled at selected depths and studied to
determine the movement of groundwater and the amount,
distribution, and type of contaminant.
Organic:
Compounds composed of carbon, including materials such as
solvents, oils, and pesticides which are not easily dissolved in
water.
Plume:
A volume of a substance that moves from its source to places
farther away from the source. Plumes can be described by the
volume of air or water they occupy and the direction they
move. For example, a plume can be a column of smoke from a
chimney or a substance moving with groundwater.
Remedial investigation:
The CERCLA process of determining the type and extent of
hazardous material contamination at a site.
Route of exposure:
The way people come into contact with a hazardous substance.
Three routes of exposure are breathing [inhalation], eating or
drinking [ingestion], or contact with the skin [dermal
contact].
Surface Water:
Water on the surface of the earth, such as in lakes, rivers,
streams, ponds, and springs [compare with groundwater].
US Environmental Protection Agency (EPA):
Established in 1970 to bring together parts of various
government agencies involved with the control of pollution.
Volatile organic compound (VOC):
An organic (carbon-containing) compound that evaporates
(volatilizes) easily at room temperature. A significant number
of the VOCs are commonly used as solvents.
