Glossary
|
You may access the list of commonly used Navy Environmental
Restoration glossary items by selecting one of the Quick Links below. Once the
desired letter appears on the screen, simply scroll to view the glossary item(s)
in question.
You may easily return to select another letter of the alphabet
by clicking Back to top at the bottom of each section.
If you would like to add to the glossary, please contact
the Webmaster.
|
A B
C
D
E
F
G
H
I J
K
L
M
N O P
Q
R
S
T U
V
W
XYZ
A
|
|
|
Abandoned Well |
A
well whose use has been
permanently discontinued or
which is in a state of such
disrepair that it cannot be used
for its intended purpose. |
|
Abatement |
Reducing the degree or intensity
of, or eliminating, pollution. |
|
Abiotic |
Not
relating to living things, not
alive. |
|
Absorbance |
A
measure of the decrease in
incident light passing through a
sample into a detector. It is
defined mathematically as:
A = I (solvent) = log
Io
I (solution) I
where I = radiation intensity |
|
Absorbed Dose |
The
amount of a chemical that enters
the body of an exposed organism.
Equal to intake multiplied by an
absorption factor. |
|
Absorption |
1)
The process by which one
substance is taken into the body
of another substance. 2) The
penetration of molecules or ions
of one or more substances (gas,
liquid or solid) into the
interior of another substance.
For example, in hydrated
bentonite (a type of clay), the
water that is held between the
mica-like layers (held within
the clay) is the result of
absorption. |
|
Accelerated Operable Unit (AOU) |
An
action which prevents, controls
or responds to a release or
threatened release of hazardous
substances, pollutants, and
contaminants where prompt action
is necessary but a response
under removal authorities is not
appropriate or desirable. The
purpose of an AOU is to allow
the remedial action for that
Operable Unit to proceed prior
to completion of the final
Record of Decision (ROD) for the
total remedial action. AOUs are
particularly appropriate where
the size and complexity of the
total remedial action would
seriously delay implementation
of independent parts of the
action. AOUs will only proceed
after complying with applicable
procedures in the NCP. It is not
intended that AOUs diminish the
requirements for, delay the
conduct of, or conflict with the
total remedial action. |
|
Accident Site |
The
location of an unexpected
occurrence, failure or loss,
either at a plant or along a
transportation route, resulting
in a release of hazardous
materials. |
|
Accuracy |
The
degree of agreement between a
measured value and a true,
expected value. |
|
Acetone |
A
colorless, volatile liquid with
a sweet odor. It is considered
the least toxic solvent in
industry. It can occur
naturally. It is used in the
production of lubricating oils,
chloroform, pharmaceuticals,
pesticides, paints, varnishes
and lacquers. If present in
water, it is more likely to
volatilize or biodegrade before
bioaccumulating or adsorbing to
sediments. Acetone will also
readily volatilize and
biodegrade in soil. It is also a
common laboratory contaminant,
so its presence in a sample does
not always indicate its presence
in the environment. Synonyms -
Dimethylketone and 2-propanone. |
|
Acid |
An
inorganic or organic compound
that 1) reacts with metals to
yield hydrogen; 2) reacts with a
base to form a salt; 3)
dissociates in water to yield
hydrogen ions; 4) has a pH of
less than 7.0; 5) neutralizes
bases or alkalis; and 6) turns
litmus paper red. All acids
contain hydrogen. They are
corrosive to tissue and should
be handled with care.
|
|
Acid Neutralizing Capacity |
A
measure of the ability of water
or soil to resist changes in pH. |
|
Acidic |
The
condition of water or soil that
contains a sufficient amount of
acid substances to lower the pH
below 7.0 |
|
Action Level (AL) |
1)
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 NCP. 2) Regulatory
levels recommended 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) Unless otherwise specified in
a NAVOSH standard, one-half the
relevant Permissible Exposure
Limit (PEL) or Threshold Limit
Value (TLV). See Tolerances. |
|
Activated Carbon |
A
highly adsorbent form of carbon
used to remove odors and toxic
substances from liquid or
gaseous emissions. In waste
treatment it is used to remove
dissolved organic matter from
waste water. It is also used in
motor vehicle evaporative
control systems. |
|
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, as compared
to longer, continuing exposure
over a period of time. |
|
Acute Toxicity |
The
ability of a substance to cause
poisonous effects resulting in
severe biological harm or death
soon after a single exposure or
dose, usually within 24 hours.
Also, any severe poisonous
effect resulting from a single
short-term exposure to a toxic
substance. See Chronic Toxicity,
Toxicity. |
|
Adaptation |
Changes in an organism's
structure or habits that help it
adjust to its surroundings. |
|
Adjacent Property |
Either those properties
contiguous to the boundaries of
the property being surveyed or
other nearby properties. |
|
Administrative Order |
A
legal document signed by EPA
directing an individual,
business, or other entity to
take corrective action or
refrain from an activity. It
describes the violations and
actions to be taken, and can be
enforced in court. Such orders
may be issued, for example, as a
result of an administrative
complaint whereby the respondent
is ordered to pay a penalty for
violations of a statute. |
|
Administrative Order On Consent |
A
legal agreement signed by EPA
and an individual, business, or
other entity through which the
violator agrees to pay for
correction of violations, take
the required corrective or
cleanup actions, or refrain from
an activity. It describes the
actions to be taken, may be
subject to a comment period,
applies to civil actions, and
can be enforced in court. |
|
Administrative Record (AR) |
A
compilation of information
established for all CERCLA sites
made available to the public at
the start of the Remedial
Investigation (RI) for remedial
actions, or at the time of
Engineering Evaluation/Cost
Analysis (EE/CA) for removal
actions. Information in the
Administrative Record supports
the selected remedy for remedial
actions and removal actions. |
|
Administrative Record File (ARF) |
1)
Refers to documents, as they are
being established and
maintained. Until a response
action decision has been
selected, there is no complete
administrative record for that
decision. Thus, to avoid
creating the impression that the
record is complete at any time
prior to the final selection
decision, the set of documents
is referred to as the ARF rather
than the AR. 2) A file that
contains all information used in
order to make decisions on the
selection of a response action
under CERCLA. Available for
public review and comment. |
|
Adsorption |
The
process by which a gas, vapor,
dissolved material or very small
particle adheres to the surface
of a solid due to chemical or
physical forces; the attraction
and adhesion of ions from an
aqueous solution to the solid
soil or rock surfaces with which
they are in contact. |
|
Advection |
The
transport of dissolved
contaminants by the bulk
movement of groundwater flow;
the main process driving the
movement of dissolved
contaminants. |
|
Advisory |
A
non-regulatory document that
communicates risk information to
those who may have to make risk
management decisions. |
|
Aeration |
A
process of supplying or
introducing air/oxygen into a
medium which promotes biological
degradation of organic matter in
water. The process may be
passive (as when waste is
exposed to air), or active (as
when a mixing or bubbling device
introduces the air). |
|
Aeration Tank |
A
chamber used to inject air into
water. |
|
Aerobe |
Bacteria that use oxygen as an
electron acceptor.
|
|
Aerobic |
Life or processes that require,
or are not destroyed by, the
presence of oxygen. See
Anaerobic. |
|
Aerobic Treatment |
Process by which microbes
decompose complex organic
compounds in the presence of
oxygen and use the liberated
energy for reproduction and
growth. Such processes include
extended aeration, trickling
filtration, and rotating
biological contactors. |
|
Affected Public |
The
people who live and/or work near
a hazardous waste site. |
|
Affinity |
A
chemical attraction or force
that causes the atoms of certain
elements or compounds to combine
with atoms of another element or
compound and remain in the
combined state. |
|
Air Changes per Hour (ACH)
|
The
movement of a volume of air in a
given period of time; if a house
has one air change per hour, it
means that all of the air in the
house will be replaced in a
one-hour period. |
|
Air Purification Devices
|
Respirators or filtration
devices which remove particulate
matter, gases, or vapors from
the atmosphere. These devices
range from full face piece, dual
cartridge masks with eye
protection, to half-mask face
piece, mounted cartridges with
no eye protection. |
|
Air Sparging |
General term for the technology
of introducing gases, usually
air, beneath the water table to
promote site remediation. Air
sparging can be divided into two
distinct processes: in-well
aeration and air injection.
|
|
Air Stripping |
A
treatment system that removes
volatile organic compounds
(VOCs) from contaminated
groundwater or surface water by
forcing an airstream through the
water and causing the compounds
to volatilize to the airsteam,
enabling separation of the
compounds from the water and
possible further treatment of
the airstream. |
|
Algae |
Simple rootless plants that grow
in sunlit waters, on rocks and
in soil, in proportion to the
amount of available nutrients.
They can affect water quality
adversely by lowering the
dissolved oxygen in the water.
They are food for fish and small
aquatic animals. |
|
Aliphatic Hydrocarbon |
A
compound built from carbon and
hydrogen atoms joined in a
linear chain. Petroleum products
are composed primarily of
aliphatic hydrocarbons. |
|
Aliquot |
A
measured portion of a sample
taken for analysis.
|
|
Alkali |
Any
compound having highly basic
properties; i.e., one that
readily ionizes in aqueous
solution to yield OH anions,
with a pH above 7.0, and turns
litmus paper blue. Examples are
oxides and hydroxides of certain
metals belonging to group IA of
the periodic table (Li, Na, K,
Rb, Cs, Fr). Ammonia and amines
may also be alkaline. Alkalis
are caustic and dissolve tissue.
Treat alkali burns by quickly
washing with large amounts of
water for at least 15 minutes.
Common commercial alkalis are
sodium carbonate (soda ash),
caustic soda and caustic potash,
lime, lye, waterglass, regular
mortar, portland cement, and
bicarbonate of soda. |
|
Alkaline |
The
condition of water or soil which
contains a sufficient amount of
alkali substances to raise the
pH above 7.0. |
|
Alkalinity |
The
capacity of water to neutralize
acids. |
|
Alluvial |
Relating to mud and/or sand
deposited by flowing water.
|
|
Alternative Fuels |
Substitutes for traditional
liquid, oil-derived motor
vehicle fuels like gasoline and
diesel. Includes methanol,
ethanol, compressed natural gas,
and others. |
|
Alternative Technology |
An
approach that aims to use
resources efficiently or to
substitute resources in order to
do minimum damage to the
environment. This approach
permits a large degree of
personal user control over the
technology.
|
|
Aluminum (Al) |
A
light ductile metal that is easy
to weld. It is a good conductor
of heat and electricity. When it
is exposed to air, it creates a
protective film resistant to
corrosion. It is used in alloys
with copper, zinc, manganese and
magnesium. It is a very
versatile metal and so has a
wide variety of uses: packaging
materials, utensils,
auto-bodies, airplanes, building
materials, electrical
conductors, explosives,
fireworks, abrasives, cosmetics,
paints, and even food additives.
It is a natural component in
soil, water, and air. Inhalation
of the fine powder can lead to
pulmonary fibrosis. |
|
Ambient |
Usual or natural surrounding
conditions, e.g., ambient
temperature - the natural,
uninfluenced temperature of the
surroundings.
|
|
Anabolism |
The
process whereby energy is used
to build organic compounds, such
as enzymes and nucleic acids,
that are necessary for life
functions. |
|
Anadromous |
Fish that spend their adult life
in the sea but swim upriver to
freshwater spawning grounds to
reproduce. |
|
Anaerobic |
A
life or process that occurs in,
or is not destroyed by, the
absence of oxygen. |
|
Anaerobic Decomposition
|
Reduction of the net energy
level and change in chemical
composition of organic matter
caused by microorganisms in an
oxygen free environment. |
|
Analytes |
The
chemicals for which a sample is
analyzed.
|
|
Analytical Method |
Defines the sample preparation
and instrumentation procedures
or steps that must be performed
to estimate the quantity of
analyte in a sample. |
|
Animal Studies |
Investigations using animals as
surrogates for humans with the
expectation that the results are
pertinent to humans. |
|
Anion Exchange Capacity
|
A
quantitative measure of surface
charge of an anion reported in
equivalents of exchangeable ions
per unit weight of the solid.
|
|
Anisotropic / Anisotropy
|
Having different properties in
different directions. See
isotropic. |
|
Antagonism |
1)
Interference or inhibition of
the effect of one chemical by
the action of another. 2)
An interaction of two or more
chemicals which results in an
effect that is less than the sum
of their effects taken
independently. |
|
Anthropogenic |
Of
or relating to humans or the era
of human life. Man-made. |
|
Anthropomorphic |
Ascribing human motivation,
characteristics, or behavior to
inanimate objects, animals, or
natural phenomena. |
|
Anti-Degradation Clause
|
Part of federal air and water
quality requirements prohibiting
deterioration where pollution
levels are above the legal
limit.
|
|
Applicable or Relevant and
Appropriate Requirement (ARAR)
|
Requirements, including cleanup
standards, standards of control
and other substantive
environmental protection
requirements and criteria, for
hazardous substances as
specified under Federal and
state laws and regulations, that
must be met when complying with
CERCLA and SARA. |
|
Aqueous |
Something made up of, similar
to, or containing water; watery.
|
|
Aquiclude |
A
saturated geologic unit that is
incapable of transmitting
significant quantities of water
under ordinary hydraulic
gradients.
|
|
Aquifer |
A
saturated, permeable geologic
formation or structure that is
capable of yielding water in
usable quantities under ordinary
hydraulic gradients. |
|
Aquitard |
The
less permeable beds in a
stratigraphic sequence; beds may
be permeable enough to transmit
water in quantities that are
significant in the study of
regional groundwater flow or
environmental contamination, but
their permeability is not
sufficient to allow completion
of production wells within them.
|
|
Area of Concern
(AOC) |
A
discrete area of contamination
or suspected contamination that
is in the PA/SI (or RFA) phase
and that has not been entered
into the DOD RMIS database.
|
|
Aromatic |
A
class of hydrocarbons consisting
of cyclic conjugate carbon
atoms, such as benzene or
toluene, commonly added to
gasoline in order to increase
octane. Some aromatics are
toxic. |
|
Arsenic (Ar) |
A
metalloid occurring naturally in
the earth's crust and fossil
fuels. It can be released into
the environment during
combustion of fossil fuels
containing arsenic. It is used
in the production of glass,
enamels, ceramics, oil, cloth,
linoleum, electrical
semiconductors, pigments,
fireworks, pesticides,
fungicides, veterinary
pharmaceuticals, and wood
preservatives. Soluble forms of
arsenic can be quite mobile,
while less soluble forms tend to
adsorb to sediments and soils.
It is a known human carcinogen,
and bioaccumulates to toxic
levels. |
|
Artesian Aquifer |
A
confined aquifer in which
groundwater rises in a well
above the point at which it is
naturally found in the aquifer,
due to artesian pressure. |
|
Asbestos |
A
mineral fiber that can pollute
air or water and cause cancer or
asbestosis when inhaled. EPA has
banned or severely restricted
its use in manufacturing and
construction. |
|
Ash |
The
mineral content of a product
remaining after complete
combustion. |
|
Assessment Endpoint |
Environmental characteristics,
which, if they were found to be
significantly affected, would
indicate a need for remediation
(e.g., decrease in sports
fisheries). |
|
Assimilative Capacity |
The
capacity of a natural body of
water to receive wastewaters or
toxic materials without
deleterious effects and without
damage to aquatic life or humans
who consume the water. |
|
Atmosphere-Supplying Devices
|
Respiratory protection devices
coupled to an air source. The
two types are Self-Contained
Breathing Apparatus (SCBA) and
supplied air respirators
(airline). |
|
Attenuation |
The
process by which a compound is
reduced in concentration with
distance and time through
absorption, adsorption,
degradation, dilution,
diffusion, dispersion, and/or
chemical or biological
transformation. |
|
Autochthonous |
A
term applied to rocks of which
the dominant constituents have
been formed in the natural or
original position as opposed to
prior erosion and disposition.
|
|
Autotrophic |
An
organism that produces food from
inorganic substances, e.g.
photosynthetic plants. |
|
Back to
Top |
|
|
B
|
|
|
Background Correction
|
In
data analysis, a technique to
compensate for variable
background contribution to the
instrument signal and the
determination of trace metals.
|
|
Background Level |
1)
Naturally occurring levels:
ambient concentrations of
chemicals present in the
environment that have not been
influenced by humans; 2)
Anthropogenic levels:
concentrations of chemicals that
are present in the environment
due to human-made, non-site
sources. |
|
Backwashing |
Reversing the flow of water back
through the filter media to
remove the entrapped solids.
|
|
Bacteria |
(Singular: bacterium)
Microscopic living organisms
ubiquitous in the environment,
that can aid in pollution
control by metabolizing organic
matter in sewage, oil spills or
other pollutants. However,
bacteria in soil, water or air
can also cause human, animal and
plant health problems.
|
|
Baghouse Filter |
Large fabric bag, usually made
of glass fibers, used to
eliminate intermediate and large
(greater than 20 microns in
diameter) particles. This device
operates like the bag of an
electric vacuum cleaner, passing
the air and smaller particles
while entrapping the larger
ones.
|
|
Bailer |
A
long pipe with a valve at the
lower end, used to remove slurry
from the bottom or side of a
well as it is being drilled or
to obtain a water sample from a
developed well. |
|
Barium (Ba) |
The
heaviest of the stable alkaline
earths, it is a soft,
silver-grey metal. It is used in
various alloys, paints, soap,
paper, rubber, ceramics, glass,
insecticides, oil and gas well
drilling muds, fireworks,
lubricating oil, and steel
hardening. It is naturally
abundant in nature and is found
in plant and animal tissue.
Ingestion of barium or some of
its compounds can cause muscular
problems, and it can accumulate
in the skeleton. |
|
Barrier Coating(s) |
A
layer of a material that
obstructs or prevents passage of
something through a surface that
is to be protected, e.g. grout,
caulk, or various sealing
compounds; sometimes used with
polyurethane membranes to
prevent corrosion or oxidation
of metal surfaces, chemical
impacts on various materials,
or, for example, to prevent
radon infiltration through
walls, cracks, or joints in a
house. |
|
Base |
Substances that (usually)
liberate OH anions when
dissolved in water. Bases 1)
react with acids to form salts;
2) have a pH greater than 7.0;
3) turn litmus paper blue; and
4) may be corrosive to tissue. A
strong base is called alkaline
or caustic. Examples are lye and
DRANO.
|
|
Base Neutral Acid Compound (BNA)
|
See
Semi-Volatile Organic Compound
(SVOC). |
|
Base Realignment And Closure
(BRAC) |
Refers to policy, procedures,
authorities, and
responsibilities for closing or
realigning military
installations across the
Department of Defense. Includes
environmental restoration
activities. |
|
Baseline Risk Assessment
|
An
analysis of the potential
adverse health effects (current
or future) caused by contaminant
releases from a site in the
absence of any actions to
control or mitigate these
releases. According to EPA, the
baseline risk assessment can be
used to determine whether: 1) A
release or threatened release
poses an unacceptable risk to
human health or the environment
that warrants remedial action,
and 2) A site presents an
imminent and substantial
endangerment. The primary
purpose is to provide risk
managers with an understanding
of the actual and potential
risks to human health and the
environment posed by the site
and the uncertainties associated
with the assessment. |
|
Bed Load |
Sediment particles resting on or
near the channel bottom that are
pushed or rolled along by the
flow of water. |
|
Bedrock |
Any
solid rocks exposed at the
surface or overlain by
unconsolidated materials. |
|
Bench-scale Tests |
Laboratory testing of potential
cleanup technologies.
Contaminated media from the site
are generally used to determine
the applicability of a
technology to a specific site.
See Pilot Tests and Treatability
Studies. |
|
Benthic Organism (Benthos)
|
A
form of aquatic plant or animal
life that is found on or near
the bottom of a stream, lake,
ocean or other water body. |
|
Benthic Region |
The
bottom layer of a body of water.
|
|
Bentonite |
Clay made of decomposed volcanic
ash which is used to seal wells
(hole plug). |
|
Beryllium (Be) |
A
greyish-white metal occurring
naturally in certain rocks,
soils and volcanic dust. A major
emission source to the
environment is through the fly
ash from combustion of coal and
fuel oil, which can contain the
metal. It is used in nuclear
reactors, radio and television
tubes, fluorescent tubes and
powders. It is discharged by
machine shops, ceramic and
propellant plants, and
foundries. In the environment,
it ultimately accumulates in
sediments. Beryllium can cause
severe dermatitis problems and
can be toxic if inhaled. It is a
Group B2, animal carcinogen
|
|
Best Demonstrated Available
Technology (BDAT) |
As
identified by EPA, the most
effective, commercially
available means of treating
specific types of hazardous
waste. The BDATs may change with
advances in treatment
technologies. |
|
Best Management Practice (BMP)
|
Methods that have been
determined to be the most
effective, practical means of
preventing or reducing pollution
from nonpoint sources. |
|
Bias |
Consistent deviation of measured
values from the true value,
caused by systematic errors in a
procedure. |
|
Bicarbonates |
Metal + HCO3, e.g.
NaHCO3. Can raise the
pH to a high concentration which
may be corrosive. |
|
Bioaccumulants |
Substances that increase in
concentration in living
organisms as they take in
contaminated air, water, or food
because the substances are very
slowly metabolized or excreted.
See Biological Magnification.
|
|
Bioassay |
Study of living organisms to
measure the effect of a
substance, factor, or condition
by comparing before-and-after
exposure or other data. |
|
Bioaugmentation |
The
addition of microbe cultures to
groundwater or soil to enhance
biodegradation. |
|
Bioavailability |
A
general term to describe the
accessibility of contaminants to
ecological populations.
Bioavailability consists of: 1)
a physical aspect related to
phase distribution and mass
transfer, and 2) a physiological
aspect related to the
suitability of the contaminant
as a substrate. |
|
Biobarrier |
An
In Situ remediation technology
consisting of a trench filled
with biological medium to
encourage the growth of bacteria
capable of degrading
contaminants. |
|
Biochemical Oxygen Demand (BOD)
|
A
measure of the amount of oxygen
consumed in the biological
processes that break down
organic matter in water. The
greater the BOD, the greater the
degree of pollution. |
|
Bioconcentration |
The
accumulation of a chemical in
tissues of an organism (such as
a fish) to levels greater than
in the surrounding medium in
which the organism lives. |
|
Bioconcentration Factor (BCF)
|
Provides a measure of the extent
of chemical partitioning at
equilibrium between biological
medium such as fish tissue or
plant tissue and an external
medium such as water. The higher
the BCF, the greater the
accumulation in living tissue is
likely to be. |
|
Biodegradable |
Capable of decomposing under
natural conditions.
|
|
Biodegradation |
1)
The reduction in concentration
of a chemical or physical agent
through naturally occurring
microbial activity. 2) The
process of an organic molecule
becoming transformed by
biological means. |
|
Biodegradation Rate |
The
mass of contaminant metabolized
by microorganisms per unit time.
In soil contamination this is
normalized to the mass of soil
and usually is expressed as mg
contaminant degraded/kg soil/day
(mg/kg/day).
|
|
Biodiversity |
Refers to the variety and
variability among living
organisms and the ecological
complexes in which they occur.
Diversity can be defined as the
number of different items and
their relative frequencies. For
biological diversity, these
items are organized at many
levels, ranging from complete
ecosystems to the biochemical
structures that are the
molecular basis of heredity.
Thus, the term encompasses
different ecosystem, species,
and genes.
|
|
Biological Additive |
Microbiological cultures,
enzymes, or nutrient additives
that are deliberately introduced
into a discharge for the
specific purpose of encouraging
biodegradation to mitigate the
effects of the discharge.
|
|
Biological Magnification
|
Refers to the process whereby
certain substances such as
pesticides or heavy metals move
up the food chain, work their
way into rivers or lakes, and
are eaten by aquatic organisms
such as fish, which in turn are
eaten by large birds, animals or
humans. The substances become
concentrated in tissues or
internal organs as they move up
the chain. See Bioaccumulants.
|
|
Biological Oxidation |
Decomposition of complex organic
materials by microorganisms.
Occurs in self-purification of
water bodies and in activated
sludge wastewater treatment.
|
|
Biological Oxygen Demand (BOD)
|
An
indirect measure of the
concentration of biologically
degradable material present in
organic wastes. It usually
reflects the amount of oxygen
consumed in five days by
biological processes breaking
down organic waste. |
|
Biological Treatment |
A
treatment technology that uses
bacteria to consume waste. |
|
Biomass |
All
of the living material in a
given area; often refers to
vegetation. |
|
Biome |
The
entire community of living
organisms in a single major
ecological area. See Biotic
Community. |
|
Biomonitoring |
1)
The use of living organisms to
test the suitability of
effluents for discharge into
receiving waters and to test the
quality of such waters
downstream from the discharge.
2) Analysis of blood, urine,
tissues, etc., to measure
chemical exposure in humans or
animals.
|
|
Biopile |
Soil pile constructed to allow
aerobic bioremediation by
aeration, possibly supplemented
with water and nutrients. |
|
Bioreactor |
A
container or area in which a
biological reaction or
biological activity takes place.
|
|
Bioreclamation |
The
process of making a contaminated
site usable again through
biological processes. |
|
Bioremediation |
1)
Use of living organisms to clean
up oil spills or remove other
pollutants from soil,
groundwater, or wastewater. 2)
Use of organisms such as
non-harmful insects to remove
agricultural pests or counteract
diseases of trees, plants, and
garden soil. |
|
Bioslurping |
A
technology application that
teams vacuum-assisted
free-product recovery with
bioventing to simultaneously
recover free product and
remediate the vadose zone. |
|
Biosphere |
The
portion of Earth and its
atmosphere that can support
life. |
|
Biota |
The
animal and plant life of a given
region.
|
|
Biotechnology |
Techniques that use living
organisms or parts of organisms
to produce a variety of products
(from medicines to industrial
enzymes) to improve plants or
animals or to develop
microorganisms to remove toxic
compounds from bodies of water,
or act as pesticides. |
|
Biotic Community |
A
naturally occurring assemblage
of plants and animals that live
in the same environment and are
mutually sustaining and
interdependent. See Biome. |
|
Biotransformation |
Conversion of a substance into
other compounds by organisms;
includes biodegradation. |
|
Bioventing |
The
process of aerating vadose zone
soils by means of installed
vents to stimulate in situ
biological activity and optimize
biodegradation of organic
compounds with some
volatilization occurring.
|
|
Blank |
An
artificial sample designed to
monitor the introduction of
artifacts into the sampling and
analytical process. For aqueous
samples, reagent water is used
as a blank matrix; however, a
universal blank matrix does not
exist for solid samples, but
sometimes clean sand is used as
a blank matrix. The blank is
taken through all appropriate
steps of the process. A reagent
blank is an aliquot of
analyte-free water or solvent
analyzed with the analytical
batch. Field blanks are aliquots
of analyte-free water or
solvents brought to the field in
sealed containers and
transported back to the
laboratory with the sample
containers. Trip blanks and
equipment blanks are two
specific types of field blanks.
Trip blanks are not opened in
the field. They are used to
monitor sample contamination
originating from transport,
shipping, and site conditions.
Equipment blanks are opened in
the field and the contents
poured over or through the
sampling equipment, collected in
a sample container, and returned
to the laboratory as a sample.
Equipment blanks monitor
sampling device cleanliness and
decontamination effectiveness.
|
|
Blood Borne Pathogens |
Pathogenic microorganisms that
are present in human blood and
can cause diseases in humans.
These pathogens include
hepatitis B virus (HBV) and
human immunodeficiency virus
(HIV). |
|
Bloom |
A
proliferation of algae and/or
higher aquatic plants in a body
of water; often related to
pollution, especially when
pollutants accelerate growth.
|
|
Blower |
A
unit of rotating mechanical
equipment used to increase the
pressure in a gas stream and
providing a total pressure rise
of more than 4 inches of water
and less than 14.7 psi. |
|
Boiling Point (BP) |
The
temperature at which a liquid
changes its phase to a vapor or
gas. This is the temperature at
which a liquid’s vapor pressure
is equal to the surrounding
atmospheric pressure, so the
liquid rapidly volatilizes.
|
|
Boom |
A
floating device used to contain
oil on a body of water. |
|
Bottom Ash |
The
non-airborne combustion residue
from burning pulverized coal in
a boiler which falls to the
bottom of the boiler and is
removed mechanically. Bottom Ash
is a concentration of the
non-combustible materials, which
may include toxic compounds.
|
|
BRAC Cleanup Plan (BCP)
|
The
road map for expeditious cleanup
of military facilities necessary
to facilitate conveyance of
property to communities for
redevelopment. |
|
BRAC Environmental Coordinator
(BEC) |
The
DOD representative on the Base
Closure Team; has responsibility
and implementation authorities
for environmental cleanup
programs related to the transfer
of the installation's real
property. |
|
BRAC Environmental Funding
|
Includes all NAVFAC
centrally-managed environmental
projects, except NEPA, that are
funded through the BRAC account
such as environmental studies,
clean up, compliance, and
restoration. For Marine Corps
installations, it includes
funding for only restoration
work. |
|
Brackish |
Mixed fresh and salt water.
|
|
Brine Mud |
Waste material, often associated
with well-drilling or mining,
composed of mineral salts or
other inorganic compounds. |
|
Bromine (Br) |
A
halogen that can substitute for
hydrogen in many organic
compounds, generally making the
resultant compound more toxic.
|
|
Buffer |
A
substance that reduces the
change in pH that would
otherwise be produced by adding
acids or bases to a solution. A
pH stabilizer.
|
|
By-product |
Material, other than the
principal product, generated as
a consequence of an industrial
process. |
|
Back to
Top |
|
|
C
|
|
|
Cadmium (Cd) |
A
soft metal used in
electroplating, pigments,
plastic stabilizers, batteries,
fusible alloys, soft solder, and
solder for aluminum. Pollution
sources include smelter fumes
and dust, some incineration
products, fertilizer, municipal
wastewater and sludge
discharges. It is also an
industrial byproduct of the
manufacturing of zinc, copper
and lead. Its mobility depends
on the pH and redox state of the
local environment. It can be
adsorbed to sediments and soils
or relatively soluble in surface
water or groundwater depending
on the conditions.
Bioaccumulation in the
environment is a concern.
Ingestion can cause
gastrointestinal problems, and
inhalation can cause lung
problems. |
|
Calcium (Ca) |
An
alkaline earth metal that is
very abundant in the
environment. Readily forms salts
with various metals and
halogens. When present in water,
it can indicate salinity and
alkalinity. Contributes to hard
water when present in high
concentrations. It is an
essential nutrient for animals
and humans. Not generally
considered toxic. |
|
Calibration |
The
establishment of an analytical
curve based on the absorbance,
emission intensity, or other
measured characteristic of known
standards. The calibration
standards must be prepared using
the same type of acid or
concentration of acids as used
in the sample preparation, i.e.,
the same matrix. |
|
Calibration Blank |
Usually an organic or aqueous
solution that is as free of
analyte as possible and prepared
with the same volume of chemical
reagents used in the preparation
of calibration standards and
diluted to the appropriate
volume with the same solvent
(water or organic). The
calibration blank is used to
give the null reading for the
instrument response versus
concentration calibration curve.
One calibration blank should be
analyzed with each analytical
batch or every method-specified
number of samples, whichever is
more frequent. |
|
Calibration Check |
Verification of the ratio of
instrument response to analyte
amount, a calibration check is
done by analyzing for analyte
standards in an appropriate
solvent. Calibration check
solutions are made from a stock
solution which is different from
the stock used to prepare
standards. |
|
Calibration Standards |
A
series of known standard
solutions used by the analyst
for calibration of the
instrument (i.e. preparation of
the analytical curve). |
|
Cancer |
The
development of a malignant tumor
or abnormal formation of tissue.
|
|
Cancer Risk |
Incremental probability of an
individual developing cancer
over a lifetime as a result of
exposure to a chemical. |
|
Cap |
A
layer of clay, or other
impermeable material installed
over the top of a closed
landfill to prevent infiltration
of rainwater and minimize
leachate. |
|
Capillary Action |
Upward movement of water through
very small spaces due to
molecular forces and surface
tension, called capillary
forces. |
|
Capillary Fringe |
A
zone of porous material lying
between the unsaturated and
saturated zone, just above the
water table, which may hold
water by capillary action in the
smaller void spaces. |
|
Carbon (C) |
An
element, the presence of which
can be used to separate organic
from inorganic compounds. |
|
Carbon Absorber |
An
add-on control device that uses
activated carbon to absorb
volatile organic compounds from
a gas stream. The VOCs are later
recovered from the carbon. |
|
Carbon Adsorption |
A
treatment system that removes
contaminants from groundwater or
surface water by forcing it
through tanks containing
activated carbon treated to
attract the contaminants. |
|
Carbon Dioxide (CO2)
|
A
colorless, odorless,
non-poisonous gas, which results
from fossil fuel combustion and
is normally a part of the
ambient air.
|
|
Carbon Monoxide (CO) |
A
colorless, odorless, poisonous
gas produced by incomplete
fossil fuel combustion. |
|
Carcinogen |
1)
Any substance that can cause,
aggravate, or contribute to the
production of cancer. 2) A
chemical classification for the
purpose of risk assessment based
on the weight of evidence for
human carcinogenicity according
to USEPA 1986 Guidelines for
Risk Assessment, in which
carcinogens are summarized as
follows: Group A: Human
carcinogen: Sufficient evidence
from human epidemiological
studies. Group B:
Probable Human Carcinogen: B1:
Limited evidence from human
epidemiological studies. B2:
Sufficient evidence from animal
studies and inadequate or no
data from human epidemiological
studies. Group C:
Possible Human Carcinogen:
Limited evidence of
carcinogenicity from animal
studies in the absence of human
data. |
|
Carcinogenic |
Causing or producing cancer.
|
Carcinogenic Potency Factor
(CPF) |
The
upper 95th percentile confidence
limit of the slope of the
dose-response curve; expressed
in units of (mg/kg/day)-1.
When derived from human
epidemiological data, the
carcinogenic potency factor may
be a maximum likelihood
estimate. |
|
Carrying Capacity |
1)
In recreation management, the
amount of use a recreation area
can sustain without loss of
quality. 2) In wildlife
management, the maximum number
of animals an area can support
during a given period.
|
|
CAS Registration Number
|
A
number assigned by the Chemical
Abstracts Service to identify a
chemical. |
|
Casing |
Pipe used in water well
construction generally extending
from the land surface to the top
of the well screen. The type and
size of casing used will vary
depending on well yield and
other design requirements.
|
|
Catabolism |
The
process whereby energy is
extracted from organic compounds
by breaking them down into their
component parts. |
|
Catalyst |
An
inorganic substance that changes
the speed, yield, or required
temperature of a chemical
reaction without being consumed
or chemically changed by the
chemical reaction. |
|
Catanadromous |
Fish that swim downstream to
spawn. |
|
Categorical Exclusion (CE)
|
A
class of actions which either
individually or cumulatively
would not have a significant
effect on the human environment
and therefore would not require
preparation of an Environmental
Assessment or Environmental
Impact Statement under the
National Environmental Policy
Act (NEPA). |
|
Cathodic Protection |
A
technique to prevent corrosion
of a metal surface by making it
the cathode of an
electrochemical cell. |
|
Cation Exchange Capacity
|
A
quantitative measure of surface
charge of a cation, reported in
equivalents of exchangeable ions
per unit weight of the solid.
|
|
Cells |
1)
In solid waste disposal, holes
where waste is dumped,
compacted, and covered with
layers of dirt on a daily basis.
2) The smallest structural part
of living matter capable of
functioning as an independent
unit. |
|
Characteristic |
Any
one of the four categories used
in defining hazardous waste:
ignitability, corrosivity,
reactivity, and toxicity. |
|
Characterization |
Facility or site sampling,
monitoring and analysis
activities to determine the
extent and nature of a release.
Characterization provides the
basis for acquiring the
necessary technical information
to develop, screen, analyze, and
select appropriate cleanup
techniques. |
|
Chelate |
A
coordination complex in which
more than one atom or molecule
(often an organic compound)
binds to a metal. In the
environment, chelation
effectively removes the metal:
it is no longer available for
chemical interactions or to
biota. See Complexation. |
|
Chemical Oxygen Demand (COD)
|
A
measure of the oxygen required
to oxidize all compounds, both
organic and inorganic, in water.
|
Chemical
Partitioning |
The
preferential separation of a
chemical into different media or
states. For example, many metals
are more likely to partition to
sediments than to remain in
groundwater. |
Chemical
Resistance |
The
ability of chemical protective
clothing to maintain its
integrity and protection
qualities when it comes into
contact with a hazardous
material. |
|
Chemical Stress |
The
result of a chemical reaction of
two or more materials. Examples
include corrosive materials
attacking a metal, the pressure
or heat generated by the
decomposition or polymerization
of a substance, or any variety
of corrosive actions. |
|
Chemical Treatment |
Any
one of a variety of technologies
that use chemicals or a variety
of chemical processes to treat
waste. |
|
Chemicals of Concern (COC)
|
Specific constituents that are
identified for evaluation in the
risk assessment process. |
|
Chemicals of Potential Concern
(COPC) |
Chemicals identified in the
initial stages of a site
investigation that may pose a
risk, and so are further
investigated to gather data for
a risk assessment. |
|
Chlorides (Cl-)
|
Indicative of the concentration
of salt water. Concentrations
above 250mg/L are detectable by
taste. |
|
Chlorinated Hydrocarbons
|
These include a class of
persistent, broad-spectrum
organic compounds that linger in
the environment and accumulate
in the food chain. Among them
are the insecticides DDT,
aldrin, dieldrin, heptachlor,
chlordane, lindane, endrin,
mirex, hexachloride, and
toxaphene. Other examples
include tetrachloroethene,
trichloroethene, carbon
tetrachloride, and
trichloromethane, used as
industrial solvents. |
|
Chlorinated Solvent |
An
organic hydrocarbon in which
chlorine atoms substitute for
one or more hydrogen atoms in
the compound’s structure, e.g.,
methylene chloride and
1,1,1-trichloromethane. Commonly
used in aerosol spray
containers, in highway paint,
for grease removal in
manufacturing, dry cleaning, and
other operations. The
substituted chlorine makes the
compound less flammable than the
nonsubstituted equivalent, but
more toxic. |
|
Chlorination |
The
application of chlorine to
drinking water, sewage, or
industrial waste to disinfect or
to oxidize undesirable
compounds.
|
|
Chlorine (Cl) |
A
halogen that can substitute for
hydrogen in many organic
compounds. The resulting
compounds are generally less
flammable but highly toxic and
persistent in the environment.
|
|
Chlorofluorocarbons (CFCs)
|
A
family of inert, nontoxic, and
easily liquified chemicals used
in refrigeration, air
conditioning, packaging,
insulation, or as solvents and
aerosol propellants. Because
CFCs are not destroyed in the
lower atmosphere they drift into
the upper atmosphere where their
chlorine components destroy
ozone. |
|
Chromium (Cr) |
A
heavy metal that exists
naturally as the trivalent (III)
form and is man-made in the
hexavalent (VI) form. It is used
in making chrome-steel and
chrome-nickel-steel alloys,
chrome plating of metals, brick
lining for high-temperature
industrial furnaces, dyes,
pigments, leather, wood
preservatives, and cooling tower
water treatment. The ultimate
fate of chromium is to settle
into sediments, however, it is
slightly soluble and can persist
in the water column for years
before settling. In soil,
chromium (III) tends to adhere
to soil particles whereas
chromium (VI) does not. This
process depends on the pH and
redox state of the soil.
Chromium (III) is not very toxic
because it does not
bioaccumulate and generally does
not penetrate biological
membranes. However, chromium
(VI) is considered more toxic
because of its high oxidizing
potential and it can penetrate
biological membranes. Dermal
contact with chromic acid or
chromium salts can cause lesions
and ulcers. Chromium is a Group
B, human carcinogen by
inhalation. See Heavy Metals.
|
|
Chronic Daily Intake (CDI)
|
Exposure expressed as mass of a
substance contacted per unit
body weight per unit time
averaged over a long period of
time (as a Superfund program
guideline, seven years to a
lifetime) mg/kg/day. |
|
Chronic Effect |
An
adverse effect on a human or
animal in which symptoms recur
frequently or develop slowly
over a long period of time.
|
|
Chronic Toxicity |
The
capacity of a substance to cause
long-term poisonous human health
effects. See Acute Toxicity.
|
|
Circle of Influence |
The
circular outer edge of the
depression produced in the water
table by pumping water from a
well. See Cone of Influence,
Cone of Depression. |
|
cis |
In
a chiral (directional) organic
compound, the prefix cis
indicates that the substituted
atoms are on the same side of
the compound. For example, in
cis 1,2-Dichloroethene, the
chlorine atoms are on the same
side of the carbon to carbon
double bond. The presence or
absence of cis or trans
compounds can indicate whether
biological activity or abiotic,
chemical reactions have taken
place in the environment. See
trans. |
|
Clarification |
Clearing action that occurs
during water treatment when
solids settle out. This is often
aided by centrifugal action and
chemically induced coagulation.
|
|
Clarifier |
A
tank in which solids settle to
the bottom and are subsequently
removed as sludge. |
|
Clastic Rock |
A
consolidated sedimentary rock
composed of broken fragments
that are derived from
pre-existing rocks, e.g.
sandstone, conglomerate, shale,
etc. |
|
Clay |
1)
Natural material with plastic
(flowing) properties; 2) A
composition of particles of very
fine size grades; and 3) A
composition of crystalline
fragments of hydrous-aluminum
silicate or hydrous-magnesium
silicate minerals. |
|
Clay Soil |
Soil material containing more
than 40 percent clay, less than
45 percent sand, and less than
40 percent silt. |
|
Clean Air Act (CAA) |
The
CAA was passed in 1970 as
amendments to 42 USC 7401, and
was amended in 1990. Its purpose
is to "protect and enhance the
quality of the Nation's air
resources." Its primary
application is through
Prevention of Significant
Deterioration permits to
regulate new potentially
polluting facilities. Of
increasing importance are the
National Emissions Standards for
Hazardous Air Pollutants
(NESHAPs). |
|
Clean Water Act of 1977 (CWA)
|
The
CWA amended the Federal Water
Pollution Control Act first
passed in 1956. Its objective is
to "restore and maintain the
chemical, physical and
biological integrity of the
Nation's waters." The Act's
major enforcement tool is the
National Pollutant Discharge
Elimination System (NPDES)
permit. |
|
Cleanup |
Actions taken to deal with a
release or threat of release of
a hazardous substance that could
affect humans and/or the
environment. The term "cleanup"
is sometimes used
interchangeably with the terms
remedial action, removal action,
response action, or corrective
action.
|
|
Cleanup Level |
The
residual concentration of a
hazardous substance in a medium
that is determined to be
protective of human health and
the environment under specified
exposure conditions. |
|
Cleanup Technology |
A
technology that is the whole or
part of a treatment train to
cleanup hazardous waste sites.
|
|
Climatology |
The
science that deals with the
climate and climatic phenomena.
|
|
Closeout |
Conducted when DON considers no
further response actions under
the IR Program to be appropriate
for the site and when site
cleanup confirms that no
significant threat to public
health or the environment
exists. The Navy forwards
closeout documentation to the
regulators for concurrence.
|
|
Closure |
The
regulatory process of
deactivating, stabilizing and or
decontaminating waste management
units or facilities under RCRA.
|
|
Closure Plan |
Documentation prepared to guide
the deactivation, stabilization
and surveillance of a waste
management unit or facility
under RCRA. |
|
Coagulation |
Clumping of particles in water
to settle out impurities, often
induced by chemicals such as
lime, alum, and iron salts.
|
|
Coastal Plains |
Any
plain which has its margin on
the shore of a large body of
water, particularly the sea, and
generally represents a strip of
recently emerged sea floor.
|
|
Coastal Zone |
As
defined by the NCP, all US
waters subject to the tide, US
waters of the Great Lakes,
specified ports and harbors on
inland rivers, waters of the
contiguous zone, other waters of
the high seas subject to the
NCP, and the land surface or
land substrata, groundwaters,
and ambient air proximal to
those waters. The term coastal
zone delineates an area of
federal responsibility for
response action. Precise
boundaries are determined by
EPA/USCG agreements and
identified in federal regional
contingency plans.
|
|
Cobalt (Co) |
A
hard, ductile, ferromagnetic
metal. It is rare but produced
primarily as a byproduct of
other metals. It is used in
chemical agents, electroplating,
ceramics, lamp filaments,
catalysts, dryers in printing
inks, paints and varnishes, and
in high temperature alloys.
Cobalt can be soluble in water,
but depends mainly on the
presence and characteristics of
adsorbing clay minerals and
hydrous oxides of iron,
manganese and aluminum in the
local environment. Chelation is
also possible. |
|
Code of Federal Regulation (CFR)
|
The
basic reference source for
federal rules. Published
annually, it is a compilation of
the regulations of various
federal agencies. The CFR is
divided into 50 titles according
to subject. For example, Title 7
deals with agriculture, Title 40
with the environment and Title
49 with transportation. Titles
are divided into chapters, then
to parts, sections, etc. The
section is the basic unit of the
CFR. Ideally, it consists of a
short, concise presentation of a
single point. It is important to
note that the CFRs are changed
daily by publication of the
Federal Register (FR). The CFRs
are the combination of
regulations published in the FR
for the previous year. |
|
Coefficient of Variation (CV)
|
The
standard deviation as a percent
of the arithmetic mean. |
|
Coliform Bacteria |
A
group of bacteria considered a
reliable indicator of the
adequacy of treatment for
bacterial pathogens. |
|
Coliform Index |
A
rating of the purity of water
based on a count of fecal
bacteria. |
|
Coliform Organism |
Microorganisms found in the
intestinal tract of humans and
animals. Their presence in water
indicates fecal pollution and
potentially adverse
contamination by pathogens.
|
|
Colloids |
Very small, less than 1 ðmm,
finely divided solids (that do
not dissolve) that remain
dispersed in a liquid for a long
time due to their small size and
electrical charge. |
|
Combustible |
A
term the NFPA, DOT, and others
use to classify certain
materials with low flash points
that ignite easily. Both NFPA
and DOT generally define
combustible liquids as having a
flash point of 100° F (38° C) or
higher. The NFPA classifies
nonliquid materials such as wood
and paper as ordinary
combustibles. OSHA defines
combustible liquids within the
Hazard Communication Law as any
liquid with a flash point at or
above 100° F (38° C) but below
200° F (93.3° C). |
|
Combustion |
1)
Burning, or rapid oxidation,
accompanied by release of energy
in the form of heat, light,
and/or sound. A basic cause of
air pollution. 2) Refers to
controlled burning of waste, in
which heat chemically alters
organic compounds, converting
into stable compounds such as
carbon dioxide and water. |
|
Combustion Chamber |
The
actual compartment where waste
is burned in an incinerator.
|
|
Cometabolism |
A
reaction in which microbes
transform a contaminant even
though the contaminant cannot
serve as an energy source for
the organisms. To degrade the
contaminant, the microbes
require the presence of other
compounds (primary substrates)
that can support their growth.
|
|
Comment Period |
Time provided for the public to
review and comment on a proposed
action or rule making after
publication in the Federal
Register or as a document. |
|
Commercial Waste |
All
solid waste emanating from
business establishments such as
stores, markets, office
buildings, restaurants, shopping
centers, and theaters. |
|
Commercial Waste Management
Facility |
A
treatment, storage, disposal, or
transfer facility which accepts
waste from a variety of sources,
as compared to a private
facility which normally manages
a limited waste stream generated
by its own operations.
|
|
Community |
In
ecology, a group of interacting
populations in time and space.
Sometimes, a particular
subgrouping may be specified,
such as the fish community in a
lake or the soil arthropod
community in a forest.
|
|
Community Environmental Response
Facilitation Act of 1992 (CERFA)
|
This law amends CERCLA and
requires that the federal
government identify real
property which is not
contaminated, and that offers
the greatest opportunity for
expedited reuse and
redevelopment by the community
on each facility. The identified
parcels of real property must be
either free from hazardous
substances and petroleum
products, including aviation
fuel and motor oil, and their
derivatives, or the remediation
of contamination by those
substances should be expedited
to facilitate transfer to the
public. |
|
Community Relations |
The
effort to establish two-way
communication with the public to
create understanding of
Installation Restoration Program
and related actions, to assure
public input into
decision-making processes
related to affected communities,
and to make certain that the
Navy is aware of and responsive
to public concerns. Specific
community relations activities
are required in relation to
Superfund remedial actions. The
term "public" includes citizens
directly affected by the site,
other interested citizens or
parties, organized groups,
elected officials, and
potentially responsible parties.
|
|
Community Relations Plan (CRP)
|
A
written plan of action that
provides for interaction with
the public, elected officials
and environmental groups,
including obtaining their input
at appropriate points during the
Installation Restoration (IR)
process. A CRP must be developed
and implemented for removal
actions and remedial actions at
all IR sites. It will be based
on research conducted by
community interviews with state
and local officials, citizen and
community groups, interested
residents, and local media
representatives.
|
|
Community Reuse Plan |
The
basis for the proposed action
and alternatives addressed in
the DOD Component's EIS or other
NEPA analyses. |
|
Community Water System |
In
Virginia, as defined by the
Virginia Department of Health, a
water system serving at least 25
individuals or more than 15
residential connections. |
|
Comparability |
A
qualitative measure of the
confidence with which one data
set can be compared to another.
Sample data should be comparable
with other measurement data for
similar samples and sample
conditions. |
|
Completeness |
A
measure of the amount of valid
data obtained from a measurement
system compared to the amount
that was expected to be obtained
under routine operating
conditions. |
|
Complexation |
Electrostatic association of
positively charged metal ions
and negatively charged organic
matter, usually with two or more
points of attachment. See
Chelate. |
|
Composite Sample |
A
representative sample created by
the homogenization of multiple
samples from multiple sampling
locations within the same
| | | | | | | | |