Abatement Debris. Waste from remediation activities<
/NP>.
Abatement. Reducing the degree or intensity of,
or eliminating, pollution.
Absorbed Dose. In exposure assessment, the amount of a substance that penetrates an exposed organism 's
absorption barriers (e.g.,, skin, lung tis
sue, gastrointestinal tract) through physical or biologi
cal processes. The term is synonymous with internal dose
.
Absorption Barrier. Any of the exchange sites o
f the body that permit uptake of various substances<
/NP> at different rates (e.g., skin, lung t
issue, and gastrointestinal-tract wall)
Absorption. The uptake of water , other flu
ids, or dissolved chemicals by a cell or an org
anism (as tree roots absorb dissolved nutrients in
soil.)
Accident Site. The location of an unexpected occurre
nce, failure or loss, either at a plant or
along a trans - portation route, resulting in a release
of hazardous materials.
Acclimatization. The physiological and behavioral ad
justments of an organism to changes in its
environment.
Acid Aerosol. Acidic liquid or solid particles
small enough to become airborne. High concentrations can irritate
the lungs and have been associated with respiratory diseases
like asthma.
Acid Deposition. A complex chemical and atmospheric
phenomenon that occurs when emissions of sulfur and
nitrogen compounds and other substances are transformed
by chemical processes in the atmosphere, often far from
the original sources, and then deposited on earth in ei
ther wet or dry form. The wet forms, popularly called "<
NP>acid rain," can fall to earth as rain, snow<
/NP>, or fog. The dry forms are acidic gases or part
icul - ates.
Acid Mine Drainage. Drainage of water from
areas that have been mined for coal or other mineral ore
s. The water has a low pH because of its <
NP>contact with sulfur-bearing material and is harmful to aq
uatic organisms.
Acid Neutralizing Capacity. Measure of ability
of a base (e.g., water or soil) to res
ist changes in pH.
Acid Rain. (See. acid deposition)
Acidic. The condition of water or soil
that contains a sufficient amount of acid substances to
lower the pH below 7.0.
Action Levels. 1. Regulatory levels recommended by E
PA for enforcement by FDA and USDA when pesticide residues occur in food or feed commodities
NP> for reasons other than the direct application of the pesti - cide. As opposed to "tolerances" which are esta
blished for residues occurring as a direct result of proper usage, action levels are set for inadvertent res
idues resulting from previous legal use or accidental co
ntami - nation. 2. In the Superfund program, the existen
ce of a contaminant concentration in the environment high enough to warrant action or trigger a response un
der SARA and the National Oil and Hazardous Substanc
es Contingency Plan. The term is also used in other regu
latory programs. (See. tolerances.)
Activated Carbon. A highly adsorbent form of carbon<
/NP> 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 drinki
ng water. It is also used in motor vehicle evaporative c
ontrol systems.
Activated Sludge. Product that results when primary
effluent is mixed with bacteria-laden sludge and then agitat
ed and aerated to promote biological treatment, speeding the
breakdown of organic matter in raw sewage undergoin
g secondary waste treatment.
Activator. A chemical added to a pesticide to i
ncrease its activity.
Active Ingredient. In any pesticide product, the com
ponent that kills, or otherwise controls, target pests.
Pesticides are regulated primarily on the basis of activ
e ingredients.
Activity Plans. Written procedures in a school 's asbestos-management plan that detail the steps a Local Education A gency (LEA) will follow in perfor
ming the initial and additional cleaning, operation<
/NP> and maintenance-program tasks; periodic surveillance; and reinspection required by the Asbestos Hazard Emergency
Response Act (AHERA).
Acute Exposure. A single exposure to a toxic substan
ce which may result in severe biological harm or death
NP>. Acute exposures are usually characterized as lasting no long
er than a day, as compared to longer, continuing exposure over a period of time.
Acute Toxicity. The ability of a substance to c
ause severe biological harm or death soon after a si
ngle exposure or dose. Also, any poisonous effect r
esulting from a single short-term exposure to a toxic substan
ce. (Seechronic toxicity toxicity, toxicity.Ada
ptation
Changes. Changes an organism 'sphysiological structu
re structure function function habits habits that <
NP>it it to survive new surroundings Add-on Control
Device ControlAn air pollution control device control device
such carbon absorber absorber incinerator incinerator t
hat the pollution pollution an exhaust gas The contr
ol device control device usually does not the process proces
s being controlled and thus is "add-ontechnology technology, as o
pposed a scheme scheme to pollution pollution through the basic process itself Adequately Wet
Adequately Asbestos. Asbestos material material that sufficiently mixed or the release with liquid to prevent the release
particulates particulates.
Dose Dose. exposure assessment the amount the a
mount a substance substance given a test test subject humanhuman animal animal) to dose-response relationshi
ps relationships. exposure exposure chemicals chemi
cals is usually this quantity this quantity is often potentia
l dose Administrative Order
Administrative A legal document legal document signed EPA EPA an individual business, business, other entity
entity to corrective action action or refrain an activi
ty It. It the violations violations actions actions to be taken, and can be enforced court Such orders<
/NP> Such orders may be issued, example example, a result result an administrative complaint complaint the respondent
respondent is ordered to a penalty penalty violations
NP> violations a statute Administrative Order
Administrative Order Consent A legal agreement legal agr
eement signed EPA EPA an individual business, b
usiness, other entity entity through the violator violat
or agrees to pay correction correction violations violat
ions, the required corrective or cleanup actions actions
, or refrain an activity It. It the actions act
ions to be taken, may be subject a comment period period, applies
civil actions actions, and can be enforced court Ad
ministrative Procedures
Act Procedures A law A law spells spells proced
ures procedures requirements requirements related the pr
omulgation promulgation regulations Administrative Recor
d
Administrative All documents All documents EPA EPA consi
dered or relied on in the response action action a Superfund
site site, culminating the record record decision d
ecision remedial action action an action memorandum acti
on memorandum removal actions Adsorption.
Removal. Removal a pollutant pollutant air air
water water by the pollutant pollutant the surface
NP> surface a solid material materiale.g. an advance
d method advanced method of waste waste in which carbon<
/NP> carbon organic matter matter waste-water Adulte
rants.
Chemical impurities Chemical impurities substances subst
ances that law law do not belong a food food, pestic
ide pesticide.
Adulterated. Any pesticide Any pesticide strength streng
th purity purity falls the quality quality stated it
s label label. A food A feed, feed, pr
oduct product that illegal pesticide residues residues.
Treatment A level A level wastewater treatment
treatment more stringent secondary treatment treatment; an 85
- percent reduction reduction conventional pollutant concentrati
on concentration a significant reduction reduction non -
conventional pollutants pollutants. Sometimes tertiary treatment
treatment.
Wastewater TreatmentAny treatment Any treatment sewa
ge sewage that goes the secondary secondary biological w
ater treatment stage stage and the removal removal nutri
ents nutrients such phosphorus phosphorus nitrogen
nitrogen a high percentage percentage of solids solids.
(See secondary treatment secondary treatment.Adverse
Effects DataFIFRA. FIFRA a pesticide registrant reg
istrant to data data EPA EPA any studies studie
s other information information unreasonable adverse effects<
/NP> effects a pesticide pesticide any time time its
registration Advisory.
A non-regulatory document non-regulatory document that communicat
es information information those who who may have to risk management decisions Aerated Lagoon
Aerated Lagoon. A holding and/treatment pond pond that speeds the natural process process biological decomposition decomp
osition organic waste waste by the growth growth act
ivity activity bacteria bacteria degrade organic waste
NP> Aeration.
A process A process which biological degradation degrada
tion organic matter matter water The process Th
e process may be passive (as waste waste is exposed to air), or a
ctive (as when a mixing or device device the air air
Aeration Tank
AerationA chamber A chamber used to air air water Aerobic.
Life. Life or processes that require, or are not destroyed th
e presence the presence oxygen oxygen. (anaerobic.
anaerobic.Aerobic
Treatment Process. Process by microbes microbes complex organic compounds compounds the presence presence <
NP>oxygen oxygen and use the energy energy reproduction<
/NP> reproduction growth growth. Such processes processe
s include aeration aeration, filtration filtration, and
biological contactorscontactors.Aerosol
Aerosol. Small droplets Small droplets particles particl
es suspended the atmosphere atmosphere, typically sulfur
They. They are usually emitted naturally e.g.e.g.,
volcanic eruptions eruptions) and the result result of anthr
opogenic (humanactivities activities such as fossil fuels fuels. The pressurized gas pressurized gas used to substanc
es substances out a container Aerosol.
A finely A finely material material suspended air air other gaseous environment environment.
Landfill Landfill. the Clean Air Act landfills,
landfills that criteria criteria capacity age,
age, emissions rates rates set the EPA They. T
hey are required to collect and their gas emissions emis
sions. t
Public Public. The peopleThe people who live and/wor
k work a hazardous waste site site. The human population
human population adversely impacted exposure exposure a
toxic pollutant pollutant food water, air
, air, soil Afterburner.
Afterburner. incinerator technology a burner a burner lo
cated so the combustion gases gases are made to pass its
flame flame order order to smoke smoke odo
rs It. It may be attached to or be separated the inciner
ator incinerator Age Tank
AgeA tank A tank used to a chemical solution solution of
concentration concentration feed feed a chemical fe
eder feeder. Also a day tank Agent.
Any physical Any chemical, chemical, biological enti
ty entity that can be harmful an organism organism(synonymou
s stressor stressorAgent Orange
AgentA toxic herbicide toxic herbicide defoliant defolia
nt used the Vietnam conflict conflict, containing - trichloro
phen - oxyacetic acid acid (- TT) and 2dichlorophenoxyac
etic 4 acid acid (- DD) with amounts amounts di
oxin Agricultural Pollution
Agricultural Pollution. wastes wastes, runoff runoff leaching leaching pesticides pesticides fertilizers fertilizerserosion erosion dust dust from plowingi
mproper disposal disposal animal manure manure carcasses
carcassescrop residues residues, debris Agroec
osystem.
Land. Land used crops pasture, pasture, liv
estock livestockthe adjacent uncultivated land land that other vegetation vegetation wildlife wildlife; and the
atmosphere atmosphere, the soils groundwater, groun
dwater, drainage networks AHERA Designated
Person Designated Person ADPADPA person A person de
signated a Local Education Agency Agency to ensure the AHERA
requirements requirements asbestos management management abatement abatement are properly Air Binding
AirSituation. Situation air air the filter media media and both the filtration filtration backwash processes
Air Changes
Air Changes Per Hour ACHACHThe movement The movement a volume volume air air a given period period
time time; a house house one air change change
hour it, it means the air air the house ho
use will be replaced a one-hour period Air Cleaning
AirIndoor-air quality-control strategy quality-control strategy t
o various airborne particulates particulates and/gases g
ases the air Most common methods common methods are
filtration electrostatic precipitation electrostatic precipi
tation, gas sorption Air Contaminant
AirAny particulate matter particulate gas, gas, comb
ination combination thereof, other water vapor vapor. (a
ir pollutant air pollutant.Air
CurtainA method A method of oil oil Air bubblin
g Air bubbling a perforated pipe pipe an upward water fl
ow flow that the spread spread oil It. It
can also be used to fish fish from polluted water Ai
r Exchange
Rate ExchangeThe rate The rate at outside air air <
NP>indoor air air in a space Air Gap
AirOpen vertical gap vertical gap empty space space that
drinking water supply supply to be protected another water s
ystem system a treatment plant plant other location
The open gap open gap the drinking water water cont
amination contamination backflow backflow or back Air Ha
ndling
Unit HandlingEquipment. Equipment that a fan fan blower heating, heating and/or coils regulato
r controls regulator controls, drain pans pans, air filt
ers Air Mass.
A large volume large volume air air certain meteorologic
al or polluted characteristics -- e.g.a heat inversion heat
inversion smogginess smogginess--while one location
The characteristics The characteristics can change the air mass m
oves moves Air Monitoring
Air Monitoring. (monitoring. monitoringAir
/ Oil TableThe surface The surface the vadose zone
zone ambient oil oilthe pressure pressure oil o
il the porous medium medium is equal atmospheric pressure Air Padding
Air Padding. dry air air a container container to assist
the withdrawal withdrawal liquid or gas to force a liqu
efied gas such chlorine chlorine out the container A
ir Permeability
AirPermeability. Permeability soil soil respect
respect to air. Important the design design soil-gas surveys
surveys. Measured darcys darcys or Air Plenum
AirAny space Any space used to air air a building furnace, furnace, structure The space The sp
ace above a ceiling ceiling is often used an air plenum
Air Pollutant
AirAny substance Any substance air air that could, h
igh enough concentration harm man harm other animals other vegetation, vegetation, material Pollutants<
/NP>. Pollutants may include any natural natural artificial c
omposition composition airborne matter matter capable of bei
ng They. They may be the form form solid particles
NP> liquid droplets liquid gases, gases, or combinat
ion combination thereof. they, they fall two main groups
groups. 11) those emitted directly identifiable sources
sources and 22) those produced the air air int
eraction interaction two two more primary pollutants pollutants, or reaction reaction normal atmospheric constit
uents constituents, with or photoactivation photoactivation.
Exclusive pollen pollen, fog, dust dust, which are
natural origin origin, 100 contaminants contaminants have be
en Air pollutants Air pollutants are often grouped categories
categories ease ease classification classification
some of he categories categories solids. sulfur compounds sulfur volatile organic chemicals or
ganic particulate matter particulate nitrogen compounds
nitrogen oxygen compounds oxygen halogen compounds halog
enradioactive compound radioactive compound, odors A
ir Pollution AirThe presence The presence contaminants
NP> contaminants pollutant substances substances the air
air that interfere human health health welfare welfare,
or other harmful environmental effects Air Pollution
Control Device ControlMechanism. Mechanism equipment equipment that emissions emissions generated a source
source e.g.an incinerator an industrial smokestack
NP> industrial smokestack, an automobile exhaust system system) b
y pollutants pollutants that would otherwise be released the
atmosphere Air Pollution
Episode PollutionA period A period abnormally high conce
ntration concentration air pollutants pollutants, often due
low winds winds temperature inversion inversion, that ca
n illness illness death death. (episode. po
llution, pollution.Air
Quality Control RegionAir Quality
Standards QualityThe level The level pollutants pol
lutants prescribed regulations regulations that are not be exceed
ed during a time time in a area Air Quality
Criteria QualityThe levels The levels pollution pol
lution lengths lengths exposure exposure above adver
se health health welfare effects effects may Air Spargin
g
Air Sparging. air air oxygen oxygen an aquifer
aquifer to strip flush volatile contaminants contaminants air
bubbles bubbles up The ground water water and is captured <
NP>a vapor extraction system Air Stripping
AirA treatment system treatment system that volatile organic
compounds compounds VOCsVOCs) from ground water wat
er surface water water by an airstream airstream the
water water and the compounds compounds to Air Toxics
NP>
AirAny air pollutant air pollutant for a national ambient air
quality quality standard NAAQSNAAQS) does not exist (i.e.,
ozone carbon monoxide carbon PM - 10-sulfur
dioxide sulfur nitrogen oxide nitrogen oxide) that may reas
onably be anticipated to cancer cancer; respiratory, cardiovascul
ar, developmental effects effectsreproductive dysfunctions neurological disorders neurological heritable gene mutatio
ns gene mutations, other serious or irreversible chronic chr
onic acute health effects effects humans Airborne Pa
rticulates
AirborneTotal. Total particulate matter matter found the atmosphere atmosphere solid particles particles liq
uid droplets Chemical composition Chemical composition p
articulates particulates varies widely, depending location l
ocation time time year Sources.
Sources airborne particulates particulates dust. emi
ssions, emissions industrial processes combustion produc
ts combustion products the burning burning wood woo
d coal combustion products combustion products associate
d motor vehicle vehicle non-road engine exhausts exhaust
s, reactions reactions gases gases the atmosphere Airborne Release
AirborneRelease. Release any pollutant pollutant the
air Alachlor.
A herbicide A herbicide, marketed the trade name Lasso L
asso, used mainly to weeds weeds corn corn soy - bea
n fields Alar.
Trade name Trade name daminozide a pesticide a
pesticide that apples apples redder, firmer, and less likely to d
rop trees trees growers growers are ready to them It. It is also used a lesser extent extent peanut
s tart , cherries cherries, concord grapes, and other fruits.
Aldicarb. An insecticide sold under the trade name T
emik. It is made from ethyl isocyanate.
Algae. Simple rootless plants that grow in sunlit wa
ters in proportion to the amount of available n
utrients. They can affect water quality adversely b
y lowering the dissolved oxygen in the water. They
NP> are food for fish and small aquatic animals
.
Algal Blooms. Sudden spurts of algal growth, wh
ich can affect water quality adversely and - tially hazardous
changes hazardous changes in local water chemistry.
Algicide. Substance or chemical used specifical
ly to kill or control algae.
Aliquot. A measured portion of a sample taken f
or analysis. One or more aliquots make up a
sample. (See. duplicate.)
Alkaline. The condition of water or soil which contains a sufficient amount of alkali substance to raise the pH above 7.0.
Alkalinity. The capacity of bases to neutralize
acids. An example is lime added to lakes to de
crease acidity.
Allergen. A substance that causes an allergic reacti
on in individuals sensitive to it.
Alluvial. Relating to and/or sand deposited by flowing <
NP>water.
Alternate Method. Any method of sampling and an
alyzing for an air or water pollutant that is not a
reference or equivalent method but that has been demonstrate
d in specific cases-to EPA 's satisfaction-to produce results
adequate for compliance monitoring.
Alternative Compliance. A policy that allows facilit
ies to choose among methods for achieving emission-reduc
tion or risk-reduction instead of command-and control re
gulations that specify standards and how to meet them. Use of a theoretical emissions bubble over a fac
ility to cap the amount of pollution emitted while
allowing the company to choose where and how (within the faci
lity) it complies.(See. bubble, emissions tradi
ng.)
Alternative Fuels. Substitutes for traditional liqui
d, oil-derived motor vehicle fuels like gasoline an
d diesel. Includes mixtures of alcohol -based fuels<
/NP> with gasoline, methanol, ethanol, compress
ed natural gas, and others.
Alternative Remedial Contract Strategy Contractors. Governmen
t contractors who provide project management and technic
al services to support remedial response activities at N
ational Priorities List sites.
Ambient Air. Any unconfined portion of the atmospher
e. open air, surrounding air.
Ambient Air Quality Standards. (See. Criteria Pollutants
and National Ambient Air Quality Standards.)
Ambient Measurement. A measurement of the concentrat
ion of a substance or pollutant within the imme
diate environs of an organism; taken to relate it t
o the amount of possible exposure.
Ambient Medium. Material surrounding or contacting a
n organism (e.g., outdoor air, indoor air,
water, or soil, through which chemicals or pollutants can reach the organism. (See. biological med
ium, environmental medium.)
Ambient Temperature. Temperature of the surrounding
air or other medium.
Amprometric Titration. A way of measuring concentrat
ions of certain substances in water using an el
ectric current that flows during a chemical reaction.
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 or
ganic matter caused by microorganisms in an oxygen-free
environment.
Animal Dander. Tiny scales of animal skin,
a common indoor air pollutant.
Animal Studies. Investigations using animals as
surrogates for humans with the expectation tha
t the results are pertinent to humans.
Anisotropy. In hydrology, the conditions under
which one or more hydraulic properties of an aquifer
vary from a reference point.
Annular Space, Annulus. The space between t
wo concentric tubes or casings, or between the casing and the borehole wall.
Antagonism. Interference or inhibition of t
he effect of one chemical by the action of another.
Antarctic "Ozone Hole". Refers to the seasonal deple
tion of ozone in the upper atmosphere above a l
arge area of Antarctica. (See. Ozone Hole.)
Anti-Degradation Clause. Part of federal air quality
and water quality requirements prohibiting deterioratio
n where pollution levels are above the legal limit.
Anti-Microbial. An agent that kills microbes.
Applicable or Relevant and Appropriate Requirements (ARARs). Any state or federal statute that pertains
to protection of human life and the environment in addressing specific conditions or use of a part
icular cleanup technology at a Superfund site,
Applied Dose. In exposure assessment, the amount of a substance in contact with the primary absorpt
ion boundaries of an organism (e.g., skin,
lung tissue, gastrointestinal track) and available for
absorption.
Aqueous Solubility. The maximum concentration of a c
hemical that will dissolve in pure water at a reference
temperature.
Aqueous. Something made up of water.
Aquifer. An underground geological formation, or gro
up of formations, containing water. Are sources
of groundwater for wells and springs.
Aquifer Test. A test to determine hydraulic properti
es of an aquifer.
Aquitard. Geological formation that may contain grou
ndwater but is not capable of transmitting significant q
uantities of it under normal hydraulic gradients. M
ay function as confining bed.
Architectural Coatings. Coverings such as paint
and roof tar that are used on exteriors of building
s.
Area of Review. In the UIC program, the are
a surrounding an injection well that is reviewed during the
permitting process to determine if flow between aqui
fers will be induced by the injection operation.
Area Source. Any source of air pollution that i
s released over a relatively small area but which cannot be class
ified as a point source. Such sources may include ve
hicles and other small engines, small businesses an
d household activities, or biogenic sources such as
a forest that releases hydrocarbons.
Aromatics. A type of hydrocarbon, such as b
enzene or toluene, with a specific type of ring
structure. Aromatics are sometimes added to gasoline in order to increase octane. Some aromatics
are toxic.
Arsenicals. Pesticides containing arsenic.
Artesian (Aquifer or Well). Water held under pressure in porous rock or soil confined by i
mpermeable geo - logical formations.
Asbestos. A mineral fiber that can pollute air
or water and cause cancer or asbestosis when in
haled. EPA has banned or severely restricted its use
in manufacturing and construction.
Asbestos Abatement. Procedures to control fiber rele
ase from asbestos-containing materials in a building or to remove them entirely, including removal, enc
apsulation, repair, enclosure, encasement,
and opera - tions and maintenance programs.
Asbestos Assessment. In the asbestos-in-schools program,
the evaluation of the physical condition and potent
ial for damage of all friable asbestos containing <
NP>materials and thermal insulation systems.
Asbestos Program Manager. A building owner or designated
representative who supervises all aspects of the fa
cility asbestos management and control program.
Asbestos-Containing Waste Materials (ACWM). Mill tai
lings or any waste that contains commercial asbestos and is generated by a source covered by the Clean Air Act A
sbestos NESHAPS.
Asbestosis. A disease associated with inhalation of asbestos fibers. The disease makes breathing pr
ogres- sively more difficult and can be fatal.
Ash. The mineral content of a product remaining
after complete combustion.
Assay. A test for a specific chemical, micr
obe, or effect.
Assessment Endpoint. In ecological risk assessment,
an explicit expression of the environmental value to be prot
ected; includes both an ecological entity and specific a
ttributed thereof. entity (e.g., salmon are a v
alued ecological entity; reproduction and population
maintenance--the attribute -- form an assessment endpoi
nt.)
Assimilation. The ability of a body of wate
r to purify itself of pollutants.
Assimilative Capacity. The capacity of a natural bod
y of water to receive wastewaters or toxic mate
rials without deleterious effects and without damage to aquatic life or humans who consume the water.
Association of Boards of Certification. An international orga
nization representing boards which certify the operators
of waterworks and wastewater facilities.
Attainment Area. An area considered to have air qual
ity as good as or better than the national ambient air quality st
andards as defined in the Clean Air Act. An area ma
y be an attainment area for one pollutant and a non-
attainment area for others.
Attenuation. The process by which a compound is
reduced in concentration over time, through absorpt
ion, adsorption, degradation, dilution, an
d/or transformation. an also be the decrease wi
th distance of sight caused by attenuation of <
NP>light by particulate pollution.
Attractant. A chemical or agent that lures
insects or other pests by stimulating their sen
se of smell.
Attrition. Wearing or grinding down of a substance by friction. Dust from such processes contributes to
air pollution.
Availability Session. Informal meeting at a public l
ocation where interested citizens can talk with EPA
and state officials on a one-to-one basis.
Available Chlorine. A measure of the amount of
chlorine available in chlorinated lime, hypochlorite
com - pounds, and other materials used as a source
of chlorine when compared with that of liquid or ga
seous chlorines.
Avoided Cost. The cost a utility would incur to generate
the next increment of electric capacity using its
NP> own resources; many landfill gas projects' buy b
uy back rates based on avoided costs.
costs ACScale Sound Level A A measurement sound
sound the the sensitivity the the human ear us
ed to note the the intensity annoyance annoyance level s
ounds.