QH540.4
.U54
1977
                           OOOK77002

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                                                                                        anaerobic
A
abatement: The reduction  in  degree or intensity
  of pollution.

absorption: The penetration of one substance into
  or through another.

accelerator: In  radiation  science, a device that
  speeds  up charged particles such as electrons
  or protons.

acclimation:  The  physiological and behaviorial
  adjustments  of an organism to changes in  the
  environment.

acclimatization:  The adaptation over several gen-
  erations of a species to a marked change  in the
  environment.

activated  carbon:  A highly  adsorbent form  of
  carbon  used  to remove odors and toxic, sub-
  stances from gaseous emissions.  In advanced
  waste treatment, it is used to remove dissolved
  organic matter from waste water.

activated sludge: Sludge that has been aerated and
  subjected to  bacterial  action; used to  speed
  breakdown  of organic  matter in  raw  sewage
  during secondary waste treatment.

acute toxicity: Any poisonous effect  produced  by
  a single short-term  exposure, that  results  in
  severe biological harm or death.

adaptation: A change in structure or habit  of  an
  organism that produces better adjustment to  its
  surroundings

adhesion:  Molecular attraction  which  holds  the
  surfaces of two substances  in contact,  such  as
  water and rock particles.

adsorption: The attachment of the molecules of a
  liquid or gaseous substance to the surface of a
  solid.

adulterants: Chemical  impurities or  substances
  that by  law  do  not  belong in  a  food,  plant,
  animal,  or pesticide formulation.

advanced waste water treatment: The  tertiary stage
  of sewage treatment.

aeration: To circulate oxygen through a substance,
  as  in waste  water treatment  where  it  aids  in
  purification.

aerobic:  Life  or processes that  depend  on the
  presence of oxygen.
aerosol: A suspension of liquid or solid particles
  in a gas.

afterburner: An air  pollution  control device that
  removes undesirable organic gases by incinera-
  tion.

agricultural pollution: The liquid and solid wastes
  from farming, including: runoff from pesticides,
  fertilizers, and feedlots; erosion and  dust from
  plowing;  animal  manure  and  carcasses, crop
  residues, and debris.

air  curtain:  A method of containing oil spills, air
  bubbling through  a perforated pipe causes an
  upward water flow that slows the  spread of oil.
  It can also  be used to stop fish from entering
  polluted water.

air  mass: A widespread  body  of air that gains
  certain  characteristics while set in  one location.
  The characteristics change as it moves away

air  monitoring: See monitoring.

air  pollution:  The presence of contaminant sub-
  stances in the air  that  do  not disperse properly
  and interfere with  human health.

air  pollution episode: A period of abnormally high
  concentration of  air pollutants, often due  to
  low winds and temperature inversion that can
  cause illness and death.

air  quality control region: An  area designated by
  the Federal Government  in  which  communities
  share a common air pollution problem, some-
  times involving several States

air  quality criteria:  The levels of pollution and
  lengths  of exposure above which adverse effects
  may occur on health and welfare.

air  quality  standards: The level  of pollutants
  prescribed  by law  that  cannot be  exceeded
  during a specified  time in a defined area.

algae: Simple  rootless plants that grow in bodies
  of water in  relative proportion to the amounts
  of nutrients available.  Algal blooms, or sudden
  growth spurts can affect  water  quality ad-
  versely

alpha particle: The least penetrating type of radia-
  tion, usually not harmful to life.

ambient air: Any unconfined portion  of the atmos-
  phere: open air

anadromous:  Fish that  swim  upnver  to  spawn
  like salmon.

anaerobic: Life or processes that can occur with-
  out free oxygen.

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anticoagulant
anticoagulant:  A  chemical that interferes with
  blood clotting.

anti-degradation clause:  Part  of air  quality and
  water quality laws that  prohibits deterioration
  where pollution  levels are within  the legal limit

aquifer: An underground  bed or layer of earth.
  gravel, or porous stone that  contains water

area source: In air pollution, any small  individual
  fuel  combustion source, including  vehicles  A
  more precise legal  definition is available  in
  Federal regulations

asbestos:  A mineral  fiber  that can  pollute air  or
  water and cause cancer  if inhaled  or ingested

A-scale sound  level: A measurement  of sound
  approximating the  sensitivity of the human ear,
  used to  note the intensity or  annoyance  of
  sounds

assimilation: The  ability of a body  of water  to
  purify itself of pollutants

atmosphere:  The  body of air  surrounding the
  Earth

atomic pile: A nuclear reactor

attractant:  A chemical or  agent  that lures insects
  01 other pests  by stimulating their sense  of
  smell

attrition:  Wearing  ot grinding down  a  substance
  by friction.  A contributing  factor in  air pollu-
  tion, as with  dust

audiometer: An instrument that  measures hearing
  sensitivity

autotrophic: An organism that  produces  food from
  inorganic substances
B
backfill: The material used to refill an excavation.
  01 the process of doing so

background \evel:  In  air  pollution,  the level  of
  pollutants present  in  ambient air  from natural
  sources.

bacteria:  Single-celled  microorganisms  that  lack
  chlorophyll  Some cause diseases,  others aid in
  pollution  control by breaking  down organic-
  matter in air and water
baffle: A  deflector that changes  the  direction of
  flow or velocity of water, sewage, or paniculate
  matter. Also used to deaden sound.

baghouse: An  air pollution abatement  device used
  to trap patticulates  by filtering  gas streams
  through large fabric bags usually made of glass
  fibers

baling:  Compacting solid  waste  into  blocks to
  reduce volume

ballistic separator: A  machine  that sorts organic
  from inorganic  matter for composting.

band  application:  In pesticides, the  spreading of
  chemicals over 01 next to each row of plants in
  a field

bar screen:  In waste water  treatment,  a  device
  that removes large solids

basal  application: In pesticides, the spreading of a
  chemical on stems or trunks just above the soil
  line.

benthic region:  The bottom layer of a body of
  water

benthos: The  plants and animals that inhabit the
  bottom of a water body

beryllium: A metal  that  can be hazardous to
  human  health when inhaled.  It is discharged by
  machine shops, ceramic and propellant  plants.
  and foundries

beta particle:  An  elementary particle  emitted by
  radioactive  decay that may cause skin burns.  It
  is halted b\  a thin sheet of metal

bioassay:  Lsing living organisms  to measure the
  effect of a substance, factor,  or  condition

biochemical oxygen demand (BOD): The dissolved
  oxygen required to decompose organic  matter
  in water  It is a measure of  pollution since
  heavy waste  loads  have  a  high demand for
  oxygen

biodegradable: Any  substance that  decomposes
  quickly through the action of  microorganisms.

biological control:  Using means other than  chemi-
  cals to control  pests, such as predatory orga-
  nisms, sterilization, or inhibiting hormones.

biological magnification: The concentration  of cer-
  tain substances up a food chain A  very  impor-
  tant  mechanism in concentrating pesticides and
  heavy metals in organisms such  as fish.

biological  oxidation:  The  way  that bacteria  and
  microorganisms feed  on and decompose com-
  plex organic materials Used  in self-purification
  of water bodies and activated  sludge wastewater
  treatment

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                                                                         chlorine-contact chamber
biomass: The  amount  of living matter in a given
  unit of the environment.

biomonitoring: The use of living organisms to test
  water quality at a discharge site or downstream

biosphere:  The  portion of  Earth and its  atmos-
  phere that can support life

biostabilizer: A machine that converts solid waste
  into compost by grinding and aeration.

biota: All living  organisms that exist in an area

bloom: A  proliferation of  algae  and/or  higher
  aquatic plants in a body of water, often  related
  to pollution.

BOD-,: The amount of dissolved oxygen consumed
  in 5 days  by biological processes  breaking down
  organic matter in an effluent.

bog:  Wet,   spongy land usually  poorly  drained,
  highly acid  and rich in plant residue,  the result
  of lake eutrophication.

boom: A floating device used to  contain oil on a
  body of water.

botanical  pesticide: A plant-produced chemical
  used  to control pests; for example nicotine or
  strychnine.

brackish water: A mixture of fresh and salt water.

breeder: A  nuclear reactor that produces more
  fuel than  it consumes.

broadcast application:  In  pesticides,  to  spread a
  chemical  over an entire area.

buffer strips:  Strips of grass or other  erosion-
  resisting vegetation between or below cultivated
  strips or fields

burial ground (graveyard): A disposal site for
  unwanted radioactive materials that uses earth
  or water for a shield.
c
cadmium: A heavy  metal element that accumu-
  lates in the environment.

carbon dioxide (CO2):  A colorless, odorless  non-
  poisonous gas  normally part of ambient air,  a
  result of fossil fuel combustion.
carbon  monoxide (CO):  A colorless,  odorless.
  poisonous  gas  produced  by incomplete  fossil
  fuel combustion

carcenogenic: Cancer-producing.

carrying capacity:  I. In recreation, the amount of
  use a recreation area can sustain without dete-
  rioration of its quality 2  In wildlife,  the  maxi-
  mum  number of animals an area can  support
  during a given period of the  year.

catalytic converter:  An  air pollution abatement
  device  that removes organic contaminants by
  oxidizing them into  carbon  dioxide and water.

caustic soda:  Sodium hydroxide (NaOH), a strong
  alkaline substance used as the cleaning agent in
  some detergents.

cells: In solid waste disposal,  holes  where  waste
  is dumped, compacted and covered with layers
  of dirt daily.

centrifugal collector: A mechanical system  using
  centrifugal  force to remove aerosols from a gas
  stream or to de-water sludge.

cfs: Cubic feet per second,  a measure of the
  amount  of water passing a given point.

channelization:  To straighten and deepen  streams
  so water will move faster, a flood reduction or
  marsh drainage tactic that  can interfere  with
  waste assimilation  capacity and  disturb fish
  habitat.

chemical  oxygen  demand (COD):  A  measure of
  the oxygen required to oxidize  all compounds
  in water, organic  and inorganic

chemosterilant: A chemical that controls pests by
  preventing  reproduction.

chilling effect: The lowering of the Earth's temper-
  ature because of increased  particles  in the air
  blocking the Sun's rays.

chlorinated hydrocarbons: A class  of persistent,
  broad-spectrum insecticides,  notably DDT, that
  linger in the environment  and  accumulate in
  the food  chain. Other  examples  are aldrin,
  dieldnn, heptachlor, chlordane, lindane, endrin,
  mirex,  benzene,  hexachlonde, and toxaphene.

chlorination: The  application of chlorine to drink-
  ing water,  sewage, or industrial  waste to  disin-
  fect or to oxidize undesirable compounds.

chlorinator: A device that adds chlorine to  water
  in gas or liquid  form

chlorine-contact chamber: That part  of a  waste
  treatment plant where effluent is disinfected by
  chlorine before being discharged

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chlorosis
chlorosis:  Discoloration of normally  green  plant
  parts that  can be caused  by disease,  lack  of
  nutrients, or various air pollutants

chromium: see heavy metals

chronic: Long-lasting or frequently recurring, as a
  disease.

clarification:  Clearing  action  that occurs during
  waste water treatment  when  solids settle out,
  often aided by centrifugal action and chemically
  induced coagulation.

clarifier: A settling tank where solids are mechan-
  ically removed from  waste water.

clear  cut:  A forest  management  technique that
  involves harvesting all the trees in one area at
  one  time. Under certain soil  and slope condi-
  tions it  can  contribute sediment to  water  pollu-
  tion.

coagulation: Aclumping of particles in waste  water
  to settle out impurities, often induced by chem-
  icals such as lime or alum.

coastal zone:  Ocean waters  and  adjacent  lands
  that exert an  influence on the uses of the  sea
  and its ecology.

coefficient of haze (COH):  A  measurement  of
  visibility interference in the  atmosphere.

coffin: A  thick-walled container (usually  lead)
  used for transporting radioactive materials.

coliform  index:  A rating  of  the  purity of  water
  based on a count of fecal bacteria

coliform organism: Organisms found in the  intes-
  tinal tract  of  humans  and animals, their  pres-
  ence in  water  indicates pollution and potentially
  dangerous bacterial contamination

combined  sewers: A  system that carries  both
  sewage  and storm  water runoff  In  dry weather
  all  flow goes to  the  waste  treatment plant.
  During  a storm  only part of the flow is  inter-
  cepted due to overloading. The remaining mix-
  ture of  sewage and storm water overflows
  untreated into the receiving  stream.

combustion: Burning, or a rapid  oxidation accom-
  panied by release of energy in the form of heat
  and light, a  basic cause of air pollution
compaction: Reduction of the bulk of solid waste
  by rolling and tamping.

compost:  Relatively stable  decomposed  organic
  material.

composting: A  controlled  process of organic
  breakdown of matter. In mechanical composting
  the materials are constantly mixed and aerated
  by a machine. The ventilated cell method mixes
  and aerates materials by dropping them through
  a vertical series of aerated chambers  Using
  windrows, compost is placed in piles out in the
  open air and mixed or turned periodically.

conservation: The protection, improvement, and
  use of natural resources according to principles
  that will assure their highest economic or social
  benefits.

contact pesticide:  A chemical that kills pests when
  it touches them,  rather  than  by being eaten
  (stomach poison).

contrails:  Long narrow clouds caused when high-
  flying jets disturb the atmosphere

contour  plowing:  Farming  methods that break
  ground following the shape of the land in a way
  that discourages erosion.

coolant: A liquid or gas used to  reduce the  heat
  generated by power production in  nuclear reac-
  tors or electric  generators.

cooling tower: A  device that aids in  heat removal
  from water used as a coolant in electric power
  generating plants.

core:  The uranium-containing heart  of a nuclear
  reactor, where energy is released

cover material:  Soil used  to cover compacted
  solid waste in a sanitary landfill.

cover: Vegetation or other  material  providing
  protection

criteria:  The standards EPA has established for
  certain pollutants,  which  not only limit  the
  concentration,  but also set a limit to the number
  of violations per year.

cultural eutrophication:  Increasing the  rate at
  which  water bodies "die"  by pollution from
  human activities
comminution: Mechanical shredding or pulverizing  curie: A measure of radioactivity.
  of waste, used in  solid waste management and
  waste water treatment                          cutie-pie: An instrument used to measure radiation
                                                    levels
comminutor: A machine that grinds solids to make
  waste treatment easier                          cyclone collector:  A device that uses centrifugal
                                                    force to  pull large particles from polluted air.

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                                                                                 dystrophic lakes
D
DDT: The first  chlorinated hydrocarbon insecti-
  cide (chemical name: 1,1, l-trichlorous-2, 2-bis
  (p-chloriphenyl)-ethane.) It has a half-life of 15
  years and can collect in fatty tissues of certain
  animals. EPA  banned registration and interstate
  sale of DDT  for  virtually  all but  emergency
  uses in the U.S. in  1972 because of its persist-
  ence  in  the environment and  accumulation in
  the food chain.

decibel (dB): A unit of sound measurement.

decomposition: The breakdown of matter by  bac-
  teria.  It changes  the chemical  make-up and
  physical appearance of materials.

dermal toxicity: The  ability of a pesticide or toxic
  chemical to poison people or animals by touch-
  ing the skin

depletion curve (hydraulics): A graphical represen-
  tation  of water depletion from storage-stream
  channels,  surface soil,  and groundwater. A
  depletion curve can be drawn for  base flow,
  direct  runoff, or total flow

DES  (Diethylstilbestrol):   A  synthetic  estrogen
  used  as a growth stimulant  in food animals.
  Residues in meat  are  thought to  be carcino-
  genic.

desalinization: Removing salt from ocean or brack-
  ish water

desiccant: A chemical agent that dries out plants
  or insects causing  death

desulfurization: Removal of sulfur from fossil fuels
  to cut  pollution

detergent: Synthetic  washing agent  that  helps
  water  to remove dirt  and oil.  Most contain
  large amounts of phosphorus compounds which
  may kill useful bacteria and encourage algae
  growth in the receiving  water.

diatomaceous earth (diatomite): A chalk-like mate-
  rial used to  filter out  solid wastes  in waste
  water  treatment plants,  also found in powdered
  pesticides

diffused air: A type of aeration that forces oxygen
  into sewage by pumping air through perforated
  pipes inside a  holding tank.

digester: In waste water treatment a closed tank,
  sometimes heated to 95° F, where sludge is
  subjected to intensified  bacterial action.
digestion:  The biochemical decomposition of or-
  ganic matter. Digestion of sewage sludge occurs
  in tanks where it breaks down into gas, liquid,
  and mineral matter.

dilution ratio: The  relationship between the vol-
  ume of water in a stream and the  volume  of
  incoming waste  It  can  affect  the ability of the
  stream to assimilate waste.

disinfection:  A chemical or physical process that
  kills organisms  that cause  infectious disease.
  Chlorine is often used to disinfect sewage  treat-
  ment effluent.

dispersant: A chemical agent used  to break  up
  concentrations  of organic material  such  as
  spilled oil.

dissolved oxygen (DO): A  measure of the amount
  of oxygen  available for biochemical activity in
  a given amount of water  Adequate  levels  of
  DO  are needed to support aquatic  life.  Low
  dissolved oxygen concentrations can result from
  inadequate waste treatment.

dissolved solids: The total  of disintegrated organic
  and  inorganic  material contained in  water. Ex-
  cesses can make water  unfit to drink or use in
  industrial processes

distillation: Purifying  liquids through boiling. The
  steam condenses to pure water and  pollutants
  remain in a concentrated residue.

dose: In radiology,  the  quantity of energy  or
  radiation absorbed.

dosimeter: An instrument  that measures  exposure
  to radiation.

dredging:  To remove earth from the bottom  of
  water bodies  using a scooping machine. This
  disturbs the ecosystem  and causes  silting that
  can kill aquatic life.

dry  limestone process:  An  air  pollution control
  method that uses limestone to absorb the  sulfur
  oxides in furnaces and stack gases

dump:  A site  used  to dispose  of  solid wastes
  without environmental controls

dust:  Fine  grain  particles light enough to  be
  suspended  in air.

dustfall jar:  An open container used  to collect
  large particles from  the  air for measurement
  and analysis

dystrophic lakes:  Shallow bodies of  water that
  contain much humus  and organic  matter. They
  contain many plants but few fish and are almost
  eutrophic.

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ecological impact
E
ecological impact: The total effect of an environ-
  mental  change, natural  or  man-made, on  the
  community of living things.

ecology: The relationships  of living things to one
  another and to their environment, or the  study
  of such relationships

economic poisons: Chemicals used to control  pests
  and to defoliate cash crops such as cotton

ecosphere: See biosphere.

ecosystem: The interacting  system of a biological
  community and its nonliving surroundings.

effluent: Waste material discharged  into the  envi-
  ronment, it can be treated or untreated  Gener-
  ally refers to water pollution

electrodialysis: A  process that  uses  electrical cur-
  rent applied to permeable membranes to remove
  minerals from water. Often used to desalinize
  salt or brackish water.

electrostatic  precipitator:  An air pollution control
  device  that imparts an  electrical  charge to
  particles m a gas stream causing them to collect
  on an electrode

emergency episode: See air pollution episode

emission: Like effluent but used  in regard to air
  pollution

emission factor:  The  relationship  between the
  amount of pollution produced  and  the amount
  of raw  material  processed  For example an
  emission factor for  a blast furnace making iron
  would be  the number of pounds of particulates
  per ton of raw materials.

emission  inventory:  A  listing,  by source, of the
  amounts of air pollutants discharged  into the
  atmosphere  of a community daily. It is used to
  establish emission standards

emission standard: The maximum amount of dis-
  charge  legally  allowed  from  a single source.
  mobile or stationary
environment: The sum of all external conditions
   affecting the life, development and survival of
   an organism.

environmental impact  statement:  A document re-
   quired  of  Federal  agencies  by the  National
   Environmental Policy Act  for major projects or
   legislative  proposals  They are used in making
   decisions about the positive and negative effects
   of the undertaking, and list alternatives.

epidemiology: The study of diseases as they affect
   populations

episode (pollution):  An air pollution  incident in  a
   given area  caused by a  concentration of atmos-
   pheric  pollution  reacting  with meteorological
   conditions  that may result in  a  significant in-
   crease in illnesses or deaths

erosion: The  wearing away of land  surface by
   wind or water  Erosion occurs naturally  from
   weather 01 run-off but can be intensified by
   land-clearing practices

estuaries: Areas where fresh water meets salt
   water (bays,  mouths of rivers,  salt  marshes,
   lagoons)   These  brackish water  ecosystems
   shelter  and feed marine life, birds,  and wildlife

eutrophication: The  slow  aging process  of a lake
   evolving into a marsh and eventually disappear-
   ing  During eutrophication the lake is choked
   by abundant  plant life. Human activities that
   add  nutrients to a water body can speed  up this
   action

eutrophic  lakes:  Shallow murky water bodies that
   have lots of algae and little oxygen

evaporation ponds: Areas  where sewage  sludge is
   dumped and allowed to  dry out.
F
fabric filter: A cloth device that catches dust and
   particles from industrial emissions

fecal coliform bacteria: A group of organisms
   found in the intestinal  tracts  of people  and
   animals  Then  presence  in water  indicates pol-
   lution and possible dangerous bacterial contam-
   ination
enrichment: Sewage effluent or agricultural runoff   feedlot: A  relatively small, confined area for
  adding nutrients (nitrogen, phosphorus, carbon
  compounds) to a water body, greatly increasing
  the growth potential for algae and aquatic
  plants.
   raising cattle that results in lower  costs  but
   may  concentrate large amounts  of animal
   wastes.  The soil  cannot absorb such  large
   amounts of excrement, and runoff from feedlots
   pollutes nearby waterways with  nutrients.

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                                                                                    groundwater
fen: Low-lying land partly covered with water

filling: Depositing dirt and mud, often raised  by
  dredging, into marshy areas  to create  more
  land for real estate development It  can destroy
  the marsh ecology.

film badge: A piece of masked photographic film
  worn by nuclear workers to monitor  their ex-
  posute to radiation  Nuclear radiation darkens
  the film

filtration:  Removing  particles of solid materials
  from water, usually by passing it through  sand

floe:  A clump of solids formed in  sewage  by
  biological or chemical action

flocculation: Separation of suspended solids during
  waste water treatment by chemical  creation of
  clumps of floes

flowmeter:  A  gauge that shows the speed of  waste
  water moving through a treatment plant

flue gas: The air coming out of  a chimney after
  combustion  It can include nitrogen oxides.
  carbon oxides,  water vapor, sulfur oxide,  parti-
  cles, and many chemical pollutants

fluorides: Gaseous, solid, or dissolved compounds
  containing  fluorine that  result from industrial
  processes

fluorocarbons: A gas used as  a propellant in
  aerosols, thought  to  be modifying the  ozone
  layer in the stratosphere thereby allowing more
  harmful  solar  radiation  to  reach  the  Harth's
  surface

flume: A natural or man-made channel that diverts
  watei

fly ash: Noncombustible particles carried by flue
  gas

fog: Suspended liquid particles formed by conden-
  sation of vapor

fogging: Applying a  pesticide  by rapidly heating
  the  liquid chemical so that  it  forms very fine
  droplets  that  resemble smoke It   is used to
  destroy  mosquitoes and blackflies

food waste: Discarded animal and vegetable mat-
  ter,  also called  garbage

fossil fuels: Combustibles  derived from the  re-
  mains of ancient  plants and animals, like coal,
  oil, and natural gas
fume:  Tiny particles trapped by vapor  in  a  gas
  stream.

fumigant:  A pesticide  that  is vaporized  to  kill
  pests;  often  used  in  buildings  or  greenhouses.

fungi:  Tiny plants that lack chlorophyll   Some
  cause disease, others  stabilize sewage and break
  down solid wastes for compost.
G
game fish: Species like trout, salmon, bass, etc
  caught for sport They show more sensitivity to
  environmental changes than "rough" fish

gamma ray: The  most  penetrating waves of ra-
  diant nuclear  energy  They can be stopped by
  dense materials  like lead.

garbage: See food  waste

garbage grinding:  Use  of a household disposal to
  crush food  waste and wash it  into the sewer
  system

gasification: Conversion of a solid material, such
  as coal, into a gas for use as fuel

Geiger counter:  An electrical device that  detects
  the presence of radioactivity

generator: A  device that  converts mechanical
  energy into electrical energy

germicide:  Any  compound  that  kills disease-car-
  rying microorganisms These must be registered
  as pesticides with FPA

grain:  A  unit of weight  equal to 65 milligrams or
  2/1,000 of an ounce

grain  loading: The  rate at which particles are
  emitted from a pollution  source—measurement
  is  made by the numbers of grains per cubic-
  foot of gas emitted.

green  belts: Buffer zones created  by  restricting
  development from certain land areas.

greenhouse effect: The warming of our atmosphere
  caused  by build-up  of carbon dioxide,  which
  allows light from  the Sun's rays to heat the
  Earth but prevents loss of the heat

ground cover: Plants grown  to  keep soil  from
  eroding.

groundwater: The supply of fresh  water under the
  Harth's  surface  that  forms a natural reservoir

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habitat
H
habitat: The sum of environmental conditions in a
  specific place that is occupied by an organism,
  population, or community.

half-life: The time taken  by certain materials to
  lose half their strength. For example the half
  life of DDT is 15 years; of radium 1,580 years.

hammermill: A  high-speed machine that uses ham-
  mers and cutters to crush, grind, chip, or shred
  solid wastes.

hard  water: Alkaline water containing  dissolved
  mineral salts, that  interfere with some industrial
  processes and prevent soap from lathering.

hazardous air  pollutant:  Substances covered by
  Air Quality Criteria, which  may cause or con-
  tribute to illness or death; asbestos, beryllium,
  mercury, and vinyl chloride

hazardous waste: Waste materials which by their
  nature are inherently dangerous to handle or
  dispose of, such as old explosives, radioactive
  materials, some chemicals, and some  biological
  wastes; usually  produced in  industrial  opera-
  tions

heat island effect: A haze dome created in cities
  by  pollutants combining with the  heat trapped
  in the spaces between tall buildings. This haze
  prevents  natural  cooling of air,  and  in the
  absence of strong  winds can hold  high concen-
  trations of pollutants in  one  place.

heating season: The  coldest months of the year,
  when pollution increases in some areas because
  people burn fossil  fuels  to keep warm

heavy metals:  Metallic elements like  mercury.
  chromium, cadmium, arsenic, and  lead,  with
  high molecular weights.  They can damage living
  things at low concentrations and tend to accu-
  mulate in the food chain

herbicide: A chemical that controls  or destroys
  undesirable plants

herbivore: An animal that  feeds on plants.

heterotrophic organism: Humans and animals that
  cannot make food  from  inorganic chemicals

high density polyethylene:  A material used to make
  plastic bottles that produces toxic fumes when
  burned.

hi-volume sampler: A device used to measure and
  analyze suspended particulate pollution
holding pond: A  pond or reservoir usually made
  of earth built to store polluted runoff.

hot: Slang for radioactive material.

humus: Decomposed organic material.

hydrocarbons: Compounds  found  in  fossil fuels,
  that contain carbon and hydrogen and may  be
  carcinogenic.

hydrogen sulfide (H2S): The  gas  emitted during
  organic decomposition  that smells  like  rotten
  eggs. It is also a byproduct of oil refining and
  burning and can cause illness in heavy concen-
  trations.

hydrology: The  science dealing with the proper-
  ties, distribution, and circulation of water.
I
impedance: The rate at which a substance absorbs
  and transmits sound.

implementation plan: An outline of steps needed
  to meet  environmental quality standards by a
  set time.

impoundment:  A  body of  water confined by a
  dam, dike, floodgate, or other barrier.

incineration:  Disposal of solid, liquid, or gaseous
  wastes by burning.

incinerator: A  controlled chamber where  waste
  substances are burned.

indicator: In biology, an organism, species,  or
  community that shows the  presence of certain
  environmental conditions.

inert gas: A  vapor that  doesn't  react with other
  substances under ordinary conditions.

inertia! separator:  A device that uses centrifugal
  force to separate waste particles.

infiltration: The action of  water moving through
  small openings  in  the earth as  it  seeps  down
  into  the ground water.

inoculum:  Bacteria  placed  in compost  to start
  biological action.

integrated pest management: Combining the best
  of all useful techniques—biological, chemical.
  cultural, physical, and mechanical—into a cus-
  tom-made pest control system.

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                                                                                          mulch
interceptor  sewers:  The  collection system  that
  connects main and trunk sewers with the was-
  tewater treatment plant.  In a combined sewer
  system interceptor sewers allow some untreated
  wastes to flow directly into the  receiving
  streams so the plant won't be overloaded.

interstate carrier water supply: A source of water
  for planes, buses,  trains, and ships operating in
  more than one  State.  These sources are regu-
  lated by the Federal Government

interstate waters:  Defined by law as:  1)  waters
  that flow across  or form  a part of State  or
  international  boundaries 2) the Great  Lakes
  and 3) coastal waters.

inversion: An atmospheric condition caused by a
  layer of warm air preventing the rise of cool air
  trapped beneath it. This holds  down  pollutants
  that might  otherwise  be  dispersed,  and can
  cause an air pollution episode.

ionization chamber: A device that detects ionizing
  radiation.

isotope: A  variation of an  element that has  the
  same atomic  number  but  a  different weight
  because of its neutrons. Isotopes of an element
  may have different radioactive behavior





J            K           L

lagoon: A shallow pond  where sunlight, bacterial
  action, and oxygen work to purify waste water.

lateral sewers:  Pipes running  underneath  city
  streets that collect sewage

LC,0:  Median  lethal concentration, a  standard
  measure of toxicity.  It tells  how much of a
  substance is needed to kill half of a group of
  experimental organisms.

leachate: Materials that pollute water as it seeps
  through solid waste.

leaching: The process by which nutrient chemicals
  or contaminants are  dissolved and carried away
  by  water, or  are moved  into  a lower layer of
  soil.
lead:  A heavy  metal that may be hazardous  to
  health if breathed or swallowed

life cycle: The stages an organism  passes through
  during its existence.

lift: In a sanitary landfill, a compacted layer  of
  solid waste and the top layer of cover material.
liquefaction: Changing a solid into a liquid form.

limnology:  The study of the physical, chemical,
  meteorological, and biological aspects of fresh
  water.

limiting factor: A condition whose absence, or
  excessive concentration, exerts  some restrain-
  ing influence upon a population through incom-
  patibility  with  species  requirements or toler-
  ance.
M
marsh: Wet,  soft,  low-lying land that provides a
  niche for  many  plants and  animals. It  can be
  destroyed by dredging and filling.

masking: Blocking out one sight, sound, or smell
  with another.

mechanical turbulence: The erratic movement of
  air caused  by local obstructions such as build-
  ings.

mercury: A heavy metal, highly toxic if breathed
  or swallowed  It can accumulate in the environ-
  ment

methane: A colorless, nonpoisonous. flammable
  gas emitted by marshes and dumps undergoing
  anaerobic decomposition.

mgd: Millions  of gallons per day.  Mgd  is a
  measurement of water flow

microbes: Tiny  plants and animals, some  that
  cause disease are found  in sewage.

mist:  Liquid  particles measuring  500 to  40 mi-
  crons,  that are found by condensation of vapor.
  By comparison, fog particles are  smaller than
  40 microns

mixed liquor: Activated sludge and water contain-
  ing organic  matter being treated in an aeration
  tank.

mobile source: A moving producer of air pollution,
  mainly forms of transportation—cars, motorcy-
  cles, planes.

monitoring:  Periodic  or continuous sampling to
  determine the level of pollution or radioactivity.

muck soils: Earth  made from decaying plant  ma-
  terials

mulch: A layer  of material (wood chips, straw,
  leaves) placed around plants to  hold moisture,
  prevent weed growth, and enrich soil.

                                            9

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multiple use
multiple  use: Harmonious  use  of land  for  more
  than one  purpose; i e.. grazing of livestock,
  wildlife production, recreation,  watershed and
  timber production  Not necessarily the combi-
  nation  of  uses  that will  yield the highest eco-
  nomic  return or greatest unit output

mutagen: Any  substance that causes changes in
  the genetic structure in subsequent generations
o
N
natural gas:  A  natural fuel  containing  methane
  and  hydrocarbons that occurs in certain geo-
  logic formations.

natural selection: The  process  of survival  of  the
  fittest, by  which  organisms that  adapt to their
  environment  survive and  those  that don't dis-
  appear.

necrosis: Death of cells that can discolor areas on
  a plant or kill  the entire plant

nitric oxide (NO): A gas  formed by  combustion
  under high temperature and high  pressure in an
  internal  combustion  engine  It  changes into
  nitrogen  dioxide in the ambient air and contrib-
  utes to photochemical smog

nitrogen dioxide  (NO2): The  result  of  nitric oxide
  combining  with oxygen in the  atmosphere, a
  major component of photochemical smog.

nitrogenous wastes:  Animal or plant residues that
  contain large amounts of nitrogen

NO: A notation  meaning oxides of nitrogen. See
  nitric oxide

nonpoint source:  A contributing factor to  water
  pollution that can't be traced  to a specific spot;
  like agricultural fertilizer runoff,  sediment from
  construction

noise: Any  undesired sound.

NTA: Nitnlotnacetic acid, a compound proposed
  for use to replace phosphates in detergents

nuclear power  plant:  A device  that  converts
  atomic energy  into usable power, heat produced
  by a reactor makes steam  to drive electricity-
  generating turbines

nutrients: Elements or compounds essential to
  growth and development of  living  things, cai-
  bon, oxygen, nitrogen, potassium and phospho-
  rus.
off-road vehicles:  Forms of motorized transporta-
  tion  that  do not require prepared  surfaces—
  they can be used to reach remote areas

oil spill: Accidental discharge into bodies of water,
  can be controlled by chemical dispersion, com-
  bustion,  mechanical containment, and  absorp-
  tion.

oil "fingerprinting": A method that identifies oil
  spills so  the\   can be traced  back to their
  sources

oligotrophic  lakes: Deep clear lakes  with low
  nutrient  supplies  They contain little  organic
  matter and have a high  dissolved oxygen level.

oncogenic:  A  substance  that  causes tumors.
  whether benign or malignant

opacity:  The amount of light  obscured  by an
  object or substance; a window has zero opacity,
  a wall 100% opacity

open burning: Uncontrolled fires in an open dump.

open dump: see dump

open  space:  A relatively  undeveloped green or
  wooded area provided usually within an  urban
  development to minimize  feelings of congested
  living

organic: Referring to  or derived from living orga-
  nisms  In chemistry, any  compound containing
  carbon

organism: Any living thing

organophosphates: Pesticide chemicals  that  con-
  tain  phosphorus, used  to  control insects  They
  are short-lived but some can  be  toxic  when
  first applied

osmosis: The tendency of a fluid to pass  through
  a  permeable  membrane,  as  the  wall  of  a
  living cell, into a  less  concentrated solution.
  so as to equalize concentrations on both sides
  of the membrane

outfall: The plact  where an  effluent is discharged
  into receiving waters
10

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                                                                                    point source
overfire air: Air forced into the top of an  inciner-
  ator to fan the flame

overturn: The period of mixing (turnover), by top
  to bottom circulation, of previously stratified
  water masses. This phenomenon may occur m
  spring and/or fall; the result is a uniformity of
  physical  and chemical properties of the water
  at all depths.

oxidant: A substance  containing oxygen  that
  reacts chemically  in air to produce a  new
  substance,  primary  source  of  photochemical
  smog

oxidation: Oxygen combining with other elements.

oxidation  pond: A  holding area where  organic
  wastes are broken down by aerobic  bacteria

ozone  (Oj):  A  pungent, colorless, toxic gas  that
  contributes to photochemical smog.
P
packed  tower:  A  pollution control device  that
  forces dirty air  through a tower  packed  with
  crushed  rock or wood  chips  while liquid  is
  sprayed over the packing material The pollu-
  tants  in the air stream either dissolve or chemi-
  cally react with the  liquid.

pandemic: Widespread throughout an area.

PAN: (Peroxyacetyl nitrate)  a pollutant  created
  by the action of sunlight on hydrocarbons and
  nitrogen oxides in the air  An  ingredient of
  smog.

particulates: Fine liquid  or solid  particles such as
  dust,  smoke, mist, fumes, or  smog, found  in
  the air or emissions

particulate  loading: The  introduction of particu-
  lates into ambient air

pathogenic: Capable of causing disease.

PCB's  (Polychlorinated biphenyls):  A  group of
  toxic, persistent  chemicals used in transformers
  and  capacitors.  Further sale  or new use  is
  banned in 1979 by law

percolation:  Downward flow or filtering of water
  through pores or spaces in rock or soil

persistent pesticides: Pesticides that do not break
  down chemically and remain in the environment
  after a growing season
pesticide:  Any  substance used  to  control  pests
  ranging from rats, weeds, and insects to  algae
  and  fungi  Pesticides can  accumulate in the
  food chain and can  contaminate  the  environ-
  ment if misused

pesticide  tolerance: The amount  of pesticide resi-
  due  allowed  by  law to remain in or  on a
  harvested crop By using various safety factors.
  KPA  sets  these  levels well  below the  point
  where  the  chemicals  might  be harmful to con-
  sumers

pH:  A measure  of the  acidity or alkalinity of a
  material, liquid or  solid pH is represented on a
  scale of 0 to 14 with  7 being  a neutral state. 0
  most acid, and  14 most alkaline

phenols: Organic  compounds that are byproducts
  of petroleum refining, tanning, textile, dye, and
  resin manufacture  Low concentrations can
  cause taste and odor  problems in water, higher
  concentrations  can kill aquatic life.

phosphates:  Chemical  compounds  containing
  phosphorus

phosphorus: An  essential food  element that can
  contribute  to the eutrophication of water bod-
  ies

photochemical oxidants:  Air  pollutants  formed by
  the action of sunlight  on oxides of nitrogen and
  hydrocarbons

photochemical smog:  Air pollution caused by not
  one  pollutant  but  by chemical reactions of
  various pollutants   emitted  from different
  sources.

photosynthesis: The manufacture  by plants of car-
  bohydrates and oxygen  from carbon dioxide
  and water in the presence of chlorophyll, using
  sunlight as  an energy source.

phytotoxic: Something that harms plants

pig:  A container, usually lead,  used to ship or
  store radioactive materials

pile:  A nuclear reactor

plankton:  Tiny plants  and  animals  that live in
  water.

plastics: Non-metallic compounds that result  from
  a chemical  reaction, and are molded or formed
  into rigid or pliable structural material

plume: Visible emission  from a flue or chimney.

point source:  A  stationary  location where pollu-
  tants are discharged, usually from  an industry
                                                                                             11

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pollen

pollen: A fine dust produced by plants; a natural
  or background air pollutant.

pollutant:  Any introduced  substance that  ad-
  versely affects the usefulness of a resource.

pollution: The presence of matter or energy whose
  nature, location, or quantity produces undesired
  environmental effects.

polyectrolytes: Synthetic chemicals that help solids
  to clump during sewage treatment.

polyvinyl chloride:  A plastic  that releases  hydro-
  chloric acid when burned.

potable water:  Appetizing water that  is safe  for
  drinking and use in cooking.

ppm: Parts per million; a way of expressing tiny
  concentrations. In air ppm is usually a volume/
  volume ratio; in  water, a weight/volume ratio.

precipitate: A solid that separates from a solution
  because of some chemical or physical change.

precipitators: Air  pollution control  devices  that
  collect particles from an emission by mechani-
  cal or  electrical means.

pretreatment: Processes used to reduce  the
  amount of pollution in water before it  enters
  the sewers or the treatment plant.

primary  treatment: The first stage of waste water
  treatment;  removal of floating debris and solids
  by screening and sedimentation.

process weight: The total  weight of  all materials,
  including fuel, used in a manufacturing process.
  It is used to calculate  the allowable  rate of
  emission of pollutant matter from the process.

pulverization: The  crushing or grinding of mate-
  rials into small pieces.

pumping station:  A  machine installed  on sewers
  to pull the  sewage uphill. In most sewer systems
  waste  water flows  by gravity to  the treatment
  plant.

putrescible:  A substance that can rot quickly
  enough to  cause odors and attract flies.

pyrolysis: Chemical  decomposition by  extreme
  heat.
Q
R
quench tank: A water-filled  tank used  to  cool
  incinerator residues,  or  hot materials  during
  industrial processes.
rad: A unit of  measurement of any kind  of
  radiation absorbed by humans.

radiation: The  emission of particles or rays  by
  the nucleus of an atom.

radiation standards: Regulations  that govern ex-
  posure  to permissible concentrations of and
  transportation of radioactive materials.

radioactive:  Substances that emit rays either nat-
  urally or as a result of scientific manipulation.

radiobiology: The study of the  principles, mecha-
  nisms, and effects of radiation on living  things.

radioecology: The study of the effects of radiation
  on plants and animals in natural communities.

radioisotopes: Radioactive forms of chemical com-
  pounds; such as cobalt-60, used in the treatment
  of diseases.

rasp: A machine that grinds waste into a manage-
  able  material  and helps prevent odor

raw sewage: Untreated waste water.

receiving waters:  Any  body  of water where un-
  treated wastes are dumped.

recharge: Process by which water is added to the
  zone of saturation, as recharge of an aquifer.

recycling: Converting solid waste  into new prod-
  ucts by using the resources contained  in dis-
  carded materials.

red tide: A proliferation of ocean plankton that
  may kill  large numbers of  fish. This natural
  phenomenon  may be  stimulated by  the addition
  of nutrients.

refuge, wildlife: An area designated for the protec-
  tion  of wild animals,  within which  hunting and
  fishing is either prohibited or strictly controlled.

refuse: See solid waste.

refuse  reclamation:  Conversion  of solid waste into
  useful products, e.g. composting organic  wastes
  to make a soil conditioner.

rem: A measurement  of radiation by  biological
  effect on human  tissue. (Acronym for roentgen
  equivalent man.)
12

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                                                                                settling chamber
rep: A measurement of radiation by energy devel-
  opment in human tissue. (Acronym for roentgen
  equivalent physical.)

reservoir: Any holding area, natural or  artificial,
  used to store, regulate,  or control water.

resource recovery: The process of obtaining matter
  or energy  from  materials formerly discarded
  e.g. solid waste, wood chips.

reverberation: The echoes of a sound that persist
  in an  enclosed space after the sound source has
  stopped

reverse  osmosis: An  advanced method  of waste
  treatment that uses a semi-permeable membrane
  to separate water from pollutants.

Ringelmann chart: A series of shaded illustrations
  used  to  measure  the opacity of  air  pollution
  emissions.  The chart  ranges from light  grey
  (number 1) through black  (number 5)  and  is
  used to set and enforce  emission standards

riparian  rights:  Entitlement of a  land  owner  to
  the water on or bordering his property, includ-
  ing the right to prevent diversion  or misuse  of
  it upstream.

river basin: The land area drained by a  river and
  its tributaries

rodenticide: A chemical or agent  used to destroy
  rats or other rodent pests, or to prevent them
  from damaging food, crops, etc.

rough fish: Those  species not  prized  for game
  purposes or for eating;  gar, suckers, etc. Most
  are more tolerant  of changing environmental
  conditions than game species.

rubbish:  Solid  waste, excluding food  waste and
  ashes, from homes, institutions, and  work-
  places.

runoff: Water from rain,  snow melt, or  irrigation
  that flows over the ground surface  and returns
  to streams. It can collect pollutants from air  or
  land and carry them to the receiving waters.
s
salinity: The degree of salt in water.

salt water intrusion: The invasion of fresh surface
  or ground water by salt  water  If the salt water
  comes  from the ocean it's called sea  water
  intrusion.

salvage: The utilization of waste materials.
sanitation: Control of physical factors in  the  hu-
  man environment  that can harm development,
  health, or survival.

sanitary landfill, landfilling: Protecting the  envi-
  ronment  when disposing of solid waste. Waste
  is  spread  in  thin  layers,  compacted  by heavy
  machinery and covered with soil daily.

sanitary sewers: Underground pipes  that  carry
  only domestic or commercial waste, not storm-
  water.

scrap: Materials  discarded from  manufacturing
  operations that may be suitable for reprocess-
  ing.

screening:  Use of racks  of screens to  remove
  coarse floating and suspended solids from sew-
  age

scrubber:  An air  pollution control  device that
  uses a spray  of water to trap  pollutants and
  cool emissions.

secondary treatment:  Biochemical treatment  of
  wastewater after the  primary stage, using bac-
  teria to consume  the organic  wastes.  Use of
  trickling filters or  the activated sludge process,
  removes floating and settleable solids and  about
  90  percent  of oxygen  demanding  substances
  and suspended solids. Disinfection with chlorine
  is the final stage of secondary treatment.

sedimentation: Letting solids  settle out of  waste
  water by  gravity during waste water treatment.

sedimentation  tanks:  Holding areas for waste
  water where floating wastes are skimmed off
  and settled solids  are pumped out for disposal.

seepage: Water that flows through the soil.

selective pesticide:  A chemical designed to  affect
  only certain types of pests leaving  other plants
  and animals unharmed.

senescence:  The aging  process.  It can refer to
  lakes in advanced  stages of eutrophication.

septic tank: An enclosure  that stores and (proc-
  esses) wastes where no sewer system exists, as
  in  rural areas or on boats. Bacteria decompose
  the organic matter into sludge, which is  pumped
  off periodically.

settleable solids: Materials  heavy enough  to sink
  to the bottom of waste water.

settling chamber:  A  series  of screens placed in
  the way of flue gases to slow the stream of air,
  thus helping gravity to pull  particles out of the
  emission into a collection  area.
                                                                                              13

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settling tank
settling tank:  A  holding  area for  waste water.
  where heavier particles sink to the bottom and
  can be siphoned off.

sewage: The organic waste and waste  water pro-
  duced by residential and commercial establish-
  ments.

sewage lagoon: See lagoon.

sewer: A channel that  carries waste  water and
  stormwater  runoff from the source  to a  treat-
  ment plant or receiving  stream.  Sanitary sewers
  carry household and commercial  waste. Storm
  sewers  carry runoff from ram  or snow   Com-
  bined sewers are used for both purposes.

sewerage: The  entire system of sewage collection.
  treatment, and  disposal. Also applies to all
  effluent carried by sewers

shield: A wall  to protect people from exposure to
  harmful radiation.

significant deterioration:  Pollution  from a  new
  source in previously "clean" areas.

silt:  Fine particles of soil or rock that  can be
  picked  up by air or water and  deposited as
  sediment.

silviculture: Management of forest land  for timber.
  Sometimes contributes to water pollution,  as in
  clear-cutting.

sinking: Controlling oil spills by using an agent to
  trap the oil. Both  sink to  the bottom of the
  body of water and biodegrade there.

skimming: Using a machine to remove oil or
  scum from the surface of the water
soil conditioner: An  organic  material like humus
  or compost  that helps soil absorb water,  build
  a bacterial community, and distribute nutrients
  and minerals

solid waste:  Useless, unwanted,  or discarded ma-
  terial  with insufficient  liquid to be free-flowing.

solid waste disposal: The  final placement of refuse
  that cannot be salvaged or recycled.

solid waste  management:  Supervised  handling  of
  waste materials  from  their  source  through re-
  covery processes to disposal.

sonic  boom: The  thunderous noise made  when
  shock waves reach  the ground  from  a jet
  airplane exceeding the  speed of sound.

soot: Carbon dust  formed by incomplete combus-
  tion

sorption: The  action of  soaking up  or  attracting
  substances:  used  in  many pollution control
  processes

sprawl:  Unplanned development  of open land.

spoil:  Dirt or rock  that  has been  removed from its
  original  location, destroying the composition  of
  the  soil  in the process, as with strip-mining  or
  dredging.

stabilization: To convert  the  active organic matter
  in sludge into inert, harmless material

stabilization  ponds: See lagoon

stable air:  A   mass  of  air  that is  not moving
  normally,  so that it holds  rather than disperses
  pollutants
sludge: The concentration of solids removed from  stack:  A chimney  or  smokestack; a vertical pipe
  sewage during waste water treatment              that  discharges used air.
slurry: A watery  mixture of insoluble matter that
  results from some pollution control techniques

smog: Air pollution associated with oxidants.

smoke: Particles suspended in air after incomplete
  combustion of materials containing carbon

SOX: The chemical symbol for oxides of sulfur

soft detergents: Cleaning agents that break down
  in nature.

solar energy:  Power collected from sunlight, used
  most often for  heating purposes but occasion-
  ally to generate electricity.
stack effect: Used air,  as in a chimney,  that
  moves upward because  it  is warmer than the
  surrounding atmosphere.

stagnation:  Lack of motion in a mass of air or
  water, which tends to hold pollutants.

stationary  source:  A pollution location  that  is
  fixed  rather than moving. One point of pollution
  rather than widespread.

storm sewer: A system that  collects and carries
  rain  and  snow runoff  to a  point  where it can
  soak  back into the ground-water  or flow into
  surface waters

stratification: Separating into layers
14

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                                                                                   urban  runoff
strip  mining:  A  process  that  uses  machines  to
  scrape soil or rock away from mineral deposits
  just under the Earth's surface.

stripcropping: Growing crops in a systematic ar-
  rangement  of strips or bands  which  serve  as
  harriers to  wind and water erosion

sulfur dioxide (SOJ: A heavy, pungent,  colorless
  gas formed  primarily  by the combustion  of
  fossil fuels This major air pollutant is unhealthy
  for plants,  animals, and people

sump: A  depression  or  tank that catches liquid
  runoff for drainage or disposal, like a cesspool

supersonic transport (SST): A jet  airplane  that
  flies  above  the  speed of sound;  it  may be
  extremely noisy upon takeoff and landing.

surfactant: A surface active  chemical agent,  usu-
  ally made up of phosphates, used  in detergents
  to cause lathering  The phosphates may contrib-
  ute to water  pollution

surveillance system: A series of monitoring devices
  designed to determine environmental quality.

suspended  solids  (SS): Tiny  pieces  of pollutants
  floating  in  sewage  that cloud  the water and
  require special  treatment to remove.

synergism: A  cooperative action of two substances
  that results in a greater effect than both of the
  substances  could  have  had acting independ-
  ently

systemic pesticide: A chemical that  is taken up
  from  the ground or absorbed through the  sur-
  face and carried  through  the  systems of the
  organism being protected, making  it  toxic  to
  pests.
T
tailings: Residue of raw materials  or  waste  sepa-
  rated out during  the  processing of crops or
  mineral ores

teratogenic: Substances  that  are suspected of
  causing  malformations or  serious  deviations
  from the normal type, which can't be inherited,
  in 01 on animal embryos or fetuses.

terracing: Dikes built along the contour of agricul-
  tural  land to hold runoff and  sediment,  thus
  reducing erosion.
tertiary treatment:  Advanced cleaning of waste
  water that goes beyond the secondary or biolog-
  ical  stage.  It removes nutrients such as phos-
  phorus and nitrogen and most suspended solids

thermal pollution: Discharge of heated water from
  industrial  processes that can  affect the life
  processes of aquatic plants and animals

threshold dose:  The  minimum  application of  a
  given substance required  to produce a measur-
  able effect

tidal marsh:  Low.  flat marshlands traversed by
  interlaced channels and tidal sloughs and  sub-
  ject  to tidal inundation; normally, the only
  vegetation  present  is salt-tolerant  bushes and
  grasses.

tolerance: The ability of an organism to cope with
  changes in its environment. Also the safe level
  of any chemical  applied  to crops that  will be
  used as food or feed

topography. The  physical  features of  a surface
  area including relative elevations and the posi-
  tion  of natural and manmade features

toxic substances: A  chemical or mixture that  may
  present an  unreasonable risk of injury to health
  or the environment

toxicant:  A chemical that controls pests by  killing
  rather than repelling them

toxicity: The degree of danger posed by a  sub-
  stance  to animal or  plant life.

trickling filter:  A  biological treatment device
  wastewater is  trickled  over a bed of stones
  covered  with bacterial  growth, the bacteria
  break down the organic wastes in  the sewage
  and  produce cleaner water

troposphere:  The portion  of the  atmosphere be-
  tween  seven and  ten miles from  the Earth's
  surface, where clouds form

turbidimeter:  A device that  measures the amount
  of suspended solids in a liquid

turbidity: Hazy air due to the presence of particles
  and  pollutants; a similar  cloudy condition  in
  water due  to suspended silt or organic matter
u
                                                 urban runoff:  Storm water  from city streets.
                                                   usually carrying litter and organic wastes.
                                                                                             15

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vapor
V
vapor: The gaseous phase  of substances that  are
  liquid or solid at atmospheric temperature and
  pressure—such as steam.

vapor plumes: Flue gases that are visible because
  they contain water droplets.


vaporization:  The  change  of a substance from a
  liquid to a gas.

variance:  Government permission  for  a  delay  or
  exception  in the application of a given law,
  ordinance,  or regulation.

vector: An organism,  often an insect, that carries
  disease.


vinyl chloride: A chemical compound  used  in
  producing  some plastics.  Excessive exposure
  to this substance may cause cancer.

volatile: Any substance that evaporates  at a low
  temperature.
w
waste:  Unwanted materials  left over  from manu-
  facturing processes, refuse from places of hu-
  man or animal habitation.

waste water:  Water  carrying dissolved  or sus-
  pended solids from homes, farms, businesses,
  and industries.

water pollution:  The  addition  of enough  harmful
  or objectionable material to damage water qual-
  ity.

water quality criteria: The levels of pollutants
  that affect use of water for drinking, swimming,
  raising fish, farming or industrial use.

water quality standard: A  management plan that
  considers,  1)  what  water will be  used for 2)
  setting levels  to protect  those  uses 3) imple-
  menting and enforcing the water treatment plans
  and 4) protecting existing high quality waters.

watershed: The land area that drains into a stream.

water supply system:  The collection, treatment,
  storage and distribution  of potable water from
  source to consumer

water table: The level of ground water.





X          Y           Z

zooplankton:  Tiny aquatic  animals  that fish feed
  on.
                                                 First Printing 1973
                                                 Revised September  1977
                                                        For sale by the Superintendent of Documents
                                                     U S Government Printing Office, Washington, D C 20402
                                                               Stock No 055-000-00163-4
16
                                                               ft GPO • 1977 O—245-772

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United States
Environmental Protection
Agency
Office of
Public Awareness (A-107)
Washington D C 20460
Official Business
Penalty for Private Use
$300
                                           Postage and
                                           Fees Paid
                                           Environmental
                                           Protection
                                           Agency
                                           EPA 335

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