environmental engineering dictionary and directory phần 5 potx

IMF Protector™ Drinking water treatment system by Smith & Loveless, Inc.Imhoff cone Cone-shaped container used to determine the volume of settleablesolids in a specific volume of water..

IMF Protector™ Drinking water treatment system by Smith & Loveless, Inc.

Imhoff cone Cone-shaped container used to determine the volume of settleablesolids in a specific volume of water

Imhoff tank A two-story wastewater treatment tank developed by Karl Imhoff inwhich sedimentation occurs in the upper compartment and anaerobic digestionoccurs in the lower compartment Also called an “Emscher fountain.”

immediately dangerous to life or health (IDLH) The maximum environmentalconcentration of a substance from which one could escape from a 30 minuteexposure without irreversible adverse health effects

immiscible Incapable of being mixed

immunoassay The identification of a substance based on its capacity to act as anantigen

immunodeficiency A lack of one or more immune functions

Impac™ Packing media for air stripping towers by Lantec Products, Inc

Impact™ Ion exchange resins by Sybron Chemicals, Inc

impact fee Fee assessed new connections to a water or sewer system intended torecover a portion of the capital cost of the system

impeller The rotating set of vanes in a turbine, blower, or centrifugal pumpdesigned to cause rotation of a fluid mass

Imperial gallon See “gallon, Imperial.”

impermeable strata Layers of clay or dense stone in the earth through whichwater cannot penetrate in measurable quantities

impervious Not allowing the passage of water at ordinary hydrostatic pressure

impingement (1) The entrapment of fish and other marine life on the surface of

an intake screen when a high water velocity prevents escape (2) The striking

of a surface by a moving fluid

impoundment A pond, lake, or reservoir created through the use of a structuralbarrier such as a dam, levee, or dike

impressed voltage cathodic protection The use of an impressed current to vent or reduce the rate of corrosion of a metal in an electrolyte by making themetal the cathode for the impressed current

pre-Impulse® Counter-current water softeners by USFilter/Lowell

impulse turbine An energy recovery device used to recover pressure energy fromreverse osmosis brine streams

impurity A chemical substance which is unintentionally present with anotherchemical substance or mixture

IMR Infant mortality rate

IMS See “Ion Mobility Spectrometry (IMS).”

IMS® Filter media support cap for sand filters by F.B Leopold Co., Inc

in situ Treatment or disposal methods that do not require movement of nated material

contami-in vitro study A laboratory study conducted in glassware

in vivo study A study conducted in a living organism

in-channel storage The water storage volume in a channel or canal above theminimum water level required for conveyance

incidence of illness The rate of occurrence of new cases of disease in a definedpopulation over a specified period of time.

incidental recharge Groundwater recharge occurring as a result of human ities such as irrigation which are unrelated to a recharge project

activ-incineration The process of reducing the volume of a solid by burning of organicmatter

incinerator A furnace or device for incineration

inclined plate separator A series of parallel inclined plates that can be used toincrease the efficiency of clarifiers and gravity thickeners

incompatible waste A hazardous waste that may cause corrosion or decay ofcontainment materials or is unsuitable for comingling with another waste underuncontrolled conditions because of the hazardous reactions that may result

incrustant Solids formed as a crust on the inside wall of a pipe

incubate To maintain optimum environmental conditions for growth and duction of viable microbes

repro-Incutrol Biochemical oxidation measuring and temperature control apparatus forBOD incubation by Hach Co

index organism See “indicator organism.”

indicator organism Microbes that indicate the absence or presence of a specificpollutant

indirect discharger Water treatment plants that discharge pollutants to publiclyowned treatment works

indirect reuse The beneficial use of reclaimed water after releasing it for storage

or dilution into natural surface waters or groundwater

indirect source Any facility, building, property, road, or parking facility thatattracts motor vehicle traffic and, indirectly, causes pollution

induced air flotation (IAF) The clarification of suspended material using persed air bubbles that attach to hydrophobic surfaces causing materials tocollect as a froth on the surface

dis-induced draft cooling tower A cooling tower in which the air flow through thetower is induced by means of an electrically operated fan

industrial waste Waste generated by manufacturing or industrial practices that isnot a hazardous waste regulated under Subtitle C of RCRA

industrial wastewater Liquid wastes resulting from industrial practices orprocesses

inert Lacking active properties and unable to react with other substances

inertial separator A device that uses centrifugal force to separate waste particles

infectious agent Any organism that is capable of being communicated in bodytissues and causing disease or adverse health impacts in humans

infectious dose 50 (ID 50 ) The microbe dose that will infect 50% of a population

to which it is applied

infectious waste Equipment, instruments, pathological specimens, or other posable wastes that may be contaminated from persons who are suspected tohave a communicable disease or have been diagnosed with a communicabledisease

dis-infiltration (1) Water entering a sewer system through broken or defective sewerpipes, service connections, or manhole walls (2) Wind-induced air movementinto a building through openings in walls, doors, or windows.

infiltration gallery A horizontal underground conduit of screens, perforated pipes,

or porous material which collects percolating water, often under a river bed

Infinity™ Continuous later filter underdrain by Roberts Filter Group

inflammable Easily set on fire

inflow Surface and subsurface water or stormwater discharged into a sewer system

inflow/infiltration (I/I) The total quantity of water from inflow and infiltrationwithout distinguishing the source

influent Water or wastewater flowing into a basin or treatment plant

Information Collection Rule (ICR) An EPA rule requiring water utilities servingmore than 10,000 customers to conduct monitoring which will aid in thegathering of data for use in developing the D/DPB Rule and ESWTR

infrared furnace A furnace using infrared radiant heat emitted from silicon bide resistance heating elements to rapidly heat organic wastes to combustiontemperatures

car-infrared radiation Low energy radiation with wavelengths longer than visiblelight and shorter than radio waves

infrastructure The fundamental network of facilities, installations, and utilitysystems serving a community

infuse (1) To pour a liquid into or upon (2) To steep in water or liquid withoutboiling so as to extract soluble constituents

inhalable diameter The diameter of a particle considered to be less than 15 meters for humans which are capable of being inhaled and deposited anywherewithin the respiratory tract

micro-inhalation LC 50 The concentration of a substance expressed as milligrams perliter of air which is lethal for 50% of the test population

inhibitor A chemical that interferes with a chemical reaction

Inipol™ Oil slick dispersant by Elf Atochem North America, Inc

initiator A chemical that can cause the initial step in the carcinogenesis process

injection well A hole drilled below the ground surface into which wastewater ortreated effluent is discharged

inlet (1) A surface connection to a drain pipe (2) A structure at the diversion end

of a conduit (3) The upstream end of any structure through which water mayflow (4) A form of connection between the surface of the ground and a drain

or sewer for the admission of surface or storm water (5) An intake

innovative technology A process or technique which has not been fully provenunder the circumstances of its contemplated use and which represents anadvancement over the state of the art

inoculum (1) Bacterium placed in compost to start biological action (2) A mediumcontaining organisms that is introduced into cultures or living organisms

inorganic carbon The carbon present in an inorganic compound such as carbondioxide or calcium carbonate

inorganic compound Compounds that contain no carbon or contain only carbonbound to elements other than hydrogen

inorganic contaminant (IOC) An inorganic substance regulated by the EPA forcompliance with drinking water requirements.

inorganic matter Substances of mineral origin that do not contain hydrocarbonsand are not subject to decay

insecticide A pesticide compound specifically used to kill or prevent the growth

of insects

In-Situ Oxygenator™ Mechanical floating aerator by Praxair, Inc

insoluble A compound that has very low solubility

InSpectra™ UV analyzer by Azur Enviromental

Instant Ocean® Mineral concentrate used to simulate seawater salinity by ium Systems

Aquar-InstoMix In-line and in-channel mixers by Walker Process Equipment

instrument detection limit (IDL) Lowest concentration of a chemical that can

be detected by an instrument without correction for the effects of a samplematrix or method-specific parameters

instrumentation Use of technology to control, monitor, or analyze physical,chemical, or biological parameters

intake (1) The works or structures at the head of a conduit into which water isdiverted (2) The process or operation by which water is absorbed into theground and added to the saturation zone (3) The flow or rate of flow into acanal, conduit, pump, stack, tank, or treatment process before treatment

Integra® Bladder pumps by Solinst Canada Ltd

integrated exposure assessment Cumulative summation (over time) of the nitude of exposure to a toxic chemical in all media

mag-Intellisieve Rotary fine screen filter by Smith & Loveless, Inc

IntensAer Radial surface aerator formerly offered by Walker Process Equipment

inter- Prefix meaning between or among

interceptor sewer A sewer that receives flow from a number of other sewers oroutlets for disposal or conveyance to a treatment plant

intercondenser A condenser used between stages to reduce steam consumption

in the steam jet vacuum system in an evaporator system

interconnecting piping Piping, usually field-installed, that connects equipmentskids or unit processes to one another

interface The common boundary between two substances such as water and asolid and water and a gas, or between two liquids such as water and oil

interfacial tension The tension that occurs at the interface between two fluids or

a liquid and a solid

intergranular corrosion Corrosion at or near the grain boundaries

Inter-Mix® Slow speed mixer by Air-O-Lator Corp

Internalift® Enclosed screw pump by USFilter/CPC

International Process System Former supplier acquired by USFilter/CPC

International Shredder Sewage shredder by ZMI/Portec Chemical Processing

Interox America Former name of Solvay America

Inter-Sep™ Rotary screen by Dontech, Inc

interstate waters Waters that flow across or form part of state or internationalboundaries, or coastal waters

interstice An open space in granular material that is not occupied by solid material.

interstitial monitoring The continuous surveillance of the space between thewalls of an underground storage tank

interstitial water (1) Water contained in the interstices of rocks (2) Extracellularwater between cells

intra- Prefix meaning within or inside

Intracid® Water tracing dye by Crompton & Knowles Colors, Inc

inverse solubility The characteristic attributed to a substance that becomes lesssoluble with increasing temperature

inversion The abnormal atmospheric condition that occurs when the air ture increases with elevation

tempera-invert The lowest point of the internal surface of a drain, sewer, or channel at anycross section

inverted siphon A u-shaped pipe used to convey flow under a river, road, or otherobstruction Also called a “sag line.”

in-vessel composting Composting system with integral material handling and vessel mixing and aeration

in-IOC (1) See “inorganic contaminant (IOC).” (2) Inorganic chemicals

iodinator A mechanical device used to introduce iodine into water for sanitizationpurposes

iodine A nonmetallic element in the halogen group sometimes used as a disinfectant

iodine number A surrogate value indicating an activated carbon’s ability to adsorblow molecular weight organics

iodometric titration See “Winkler titration.”

ion An electrically charged atom, molecule or radical

ion chromatography (IC) A technique for separating and measuring the ties of different ions present in a sample based on their affinity for an adsorptionmedium

quanti-ion exchange (IX or IE) A chemical process involving the reversible exchange

of ions between a liquid and a solid

Ion Grabber Electrolytic purification unit by Hoffland Environmental Inc

Ion Mobility Spectrometry (IMS) Continuous emissions analyzer used to sure pollutants in gases

mea-Ion Stick® Electrostatic water treater for prevention of scale and fouling by YorkEnergy Conservation

Ionac® Ion exchange resins by Sybron Chemicals, Inc

ionic strength A measure of solution strength based on both the concentrationsand valences of the ions present

ionization The process by which an atom or molecule acquires a positive ornegative electrical charge through the loss or gain of electrons

ionization chamber A device that measures the intensity of ionizing radiation

ionizing radiation Radiation that can strip electrons from atoms

ionosphere The upper level of the earth’s atmosphere beginning at an altitude ofapproximately 80 km

Ionpure® High purity water treatment products and services by USFilter/Lowell

Iopor Low pressure ultrafiltration system formerly offered by GL&V/Dorr-Oliver,Inc.

IP Inhalable particulates

IPA Isopropyl alcohol

IPCC Intergovernmental Panel on Climate Change

IPLP® Double-pass reverse osmosis system by USFilter Corp

IPP Independent power producer

IPS Composting System In-vessel composting system by USFilter/CPC

IQS/3™ Programmable controller used to operate and monitor water treatmentsystems by Culligan International, Corp

iron A common naturally occurring metallic element found in dissolved form inmost water supplies Chemical formula is Fe

iron bacteria Bacteria capable of metabolizing ferrous iron often from water orsteel pipes See also “crenothrix polyspora.”

Iron Humate® An iron source for agricultural soils and turf grasses produced fromwater treatment plant sludges by Kemiron

Iron Remover Contact bed type iron removal system by Walker Process Equipment

iron salt An iron-based coagulant used in water and wastewater treatment

irradiated food Food subject to brief radioactivity, usually gamma rays, to killinsects, bacteria, and mold, and to permit storage without refrigeration

irradiation Exposure to radiation of wavelengths shorter than those of visible lightfor medical purposes, to sterilize foodstuffs, or to induce polymerization ofmonomers or vulcanization of rubber

irreversible effect An effect characterized by the inability of the body to partially

or fully repair injury caused by a toxic agent

irrigation The artificial application of water to meet the requirements of growingplants or grass that are not met by rainfall alone

irrigation efficiency The amount of water stored in the crop root zone compared

to the amount of irrigation water applied

irritant A substance that can cause irritation of the skin, eyes, or respiratorysystem Effects may be acute from a single high level of exposure or chronicfrom repeated low-level exposures to such compounds as chlorine, nitrogendioxide, and nitric acid

ISA Instrument Society of America

ISCO In-situ chemical oxidation

ISEP® Ion exchange systems by Advanced Separation Technologies

ISF™ Induced air flotation unit by Baker Hughes Process Systems

ISO International Organization for Standardization

ISO 9000 Certification conferred to a manufacturer that has demonstrated the bility of running an integrated business from initial design through manufacture

capa-ISO 14000 A series of guidance standards to provide businesses with a structurefor managing varied environmental concerns

ISO 14001 Environmental management system standards for manufacturing andservice industries

isobar A line on a weather map that joins all points of equal barometric pressure

isobath A line on a map connecting all points of equal depth above the surface

of a water-bearing formation or aquifer

isochrone A line on a map connecting all points having the same time of travelfor contaminants to move through the saturated zone and reach a well

isohaline A line on a map connecting points having equal amounts of salinity

isohyet A line on a map connecting points that receive equal average amounts ofprecipitation

isomer A chemical compound that has the same molecular formula but differentmolecular structure, as another compound

isopleth A line on a map connecting points at which a certain variable has thesame value

isotherm A line on a weather map connecting points that have the same temperature

isothiazalon A high molecular weight non-oxidizing biocide used to control brane biofouling

mem-isotopes Atoms with the same atomic number but different atomic weights

isthmus A narrow strip of land bounded by water on both sides and connectingtwo large land masses

ITT Marlow Former name of ITT A-C Pump

IU Industrial user

IWEM See “CIWEM.”

IWPF Industrial wastewater pretreatment facility

IWS USFilter/Industrial Wastewater Systems

IWT® Illinois Water Treatment product line of USFilter/Rockford

IX See “ion exchange (IX or IE).”

IXPER® Calcium peroxide by Solvay America

J

J See “joule (J).”

J&A Jones and Attwood product division of Waste-Tech, Inc

JAC Oxyditch Oxidation ditch treatment system formerly offered by Chemineer,Inc

Jackbolt™ Aluminum clarifier cover by Enviroquip, Inc

jacking A method of installing pipe by forcing it into a horizontal opening withhorizontal jacks

JackKnife Pivoting air header and drop pipe arrangement by Walker ProcessEquipment

Jackson turbidity unit (JTU) An obsolete unit of measure used to quantify thewater turbidity by observing the outline of a candle flame viewed through awater sample Replaced by “NTU.”

Jacquelyn™ Corrosion and zebra mussel resistant coating by Cook Screen nologies, Inc

Tech-JAPCA Journal of Air Pollution Control Association

jar test A test procedure using laboratory glassware for evaluating coagulation,flocculation, and sedimentation in a series of parallel comparisons.

Jayfloc Polyelectrolyte used to enhance liquid/solid separation by Vulcan mance Chemicals

Perfor-J-Belt Belt filter press by USFilter/Dewatering Systems

Jeffrey Screening equipment product line offered by Jones & Attwood, Inc

Jeffrey® Chain, sprocket, and related component products by Jeffrey Chain Corp

JelClear™ Granular filtration media having a coagulant bonded directly to themedia grains by BetzDearborn-Argo District

jet A stream of pressurized liquid or vapor from a nozzle or orifice

jet aeration Wastewater aeration system using floor-mounted nozzle aerators thatcombine liquid pumping with air diffusion

Jet Breaker™ Screenings washer/compactor by Headworks, Inc

Jet Plant Package wastewater treatment plant by Jet, Inc

Jet Shear Continuous mixing system using jet nozzles by Flo Trend Systems, Inc

jet stream A strong, thermally driven, high altitude wind

Jet Tech Former name of USFilter/Jet Tech

Jet Tray Deaerator by Cochrane Inc

Jet VIP™ Pulsed fabric filter by Wheelabrator Air Pollution Control, Inc

JETA Vortex type grit collector by Waste-Tech, Inc

Jeta-Matic Spray jet pressure leaf filter cleaning system by USFilter/Whittier

Jet-Chlor® Tablet chlorine disinfection system by Jet, Inc

JETIII® Fabric filter by Wheelabrator Air Pollution Control, Inc

JetMix™ Vortex mixing system for sludge storage basins by Liquid DynamicsCorp

jetsam Floating jettisoned material

Jet-Tex Leach bed filter fabric by Jet, Inc

jetty A structure that extends into an open body of water to influence currents ortides or protect a harbor

Jet-Wet™ Dry polymer feeding system by Fluid Dynamics, Inc and Ciba SpecialtyChemicals

J-Flow Gravity belt thickener by USFilter/Dewatering Systems

JH™ Series of air scrubbers for odor control by USFilter/Davis Process

Jigrit Screw-type grit washer by Jeffrey Chain Corp

J-Mate® Sludge volume reduction system by USFilter/Dewatering Systems

Johnson Filter Former name of USFilter/Johnson Screens

Johnson Screen Wedgewire screen media by USFilter/Johnson Screens

Jones and Attwood Environmental product division of Waste-Tech, Inc

joule (J) An SI unit of energy or work equal to the work done by the application

of 1 newton acting through a distance of 1 meter

Joule™ Electrochemical flocculation system by Ecoloquip Inc

journal bearing A cylindrical bearing that supports a rotating shaft

J-Press® Plate and frame filter press by USFilter/Dewatering Systems

J-Spin Centrifuge by USFilter/Dewatering Systems

J-Track™ Nonmetallic return track for chain and flight sludge collectors by ter/Envirex

USFil-JTU See “Jackson turbidity unit.”

JUD Belt tracking system for belt filter press by Klein America, Inc

junction box An enclosure within which electrical cables are connected and/orterminated

J-Vap™ Mechanical sludge dewatering and drying system by USFilter/DewateringSystems

JWI Dewatering equipment product line by USFilter/Dewatering Systems

estab-K 2 Modular™ Volumetric screw feeder by K-Tron North America

Kaldnes System Biological wastewater treatment system by Waterlink BiologicalSystems

kame A ridge or hill of stratified drift deposited by glacial meltwater

KAMET Municipal effluent treatment system by Krofta Engineering Corp

Kan-Floc™ Wastewater flocculant/coagulant by Kem-Tron

kaolin A type of fine white clay material

karst A geologic formation of irregular limestone deposits with sinks, ground streams, and caverns

under-katabatic wind A localized wind that flows down valley or mountainous slopes —usually at night — caused by the descent of cold air as the valley slopesundergo rapid nocturnal cooling

Katec® Thermal oxidizer by Megtec Systems, Inc

Kat-Floc™ Wastewater flocculant/coagulant by Kem-Tron

Katox Catalytic oxidizer by Adwest Technologies, Inc

KD-HF™ Deionization system by Kinetico Engineered Systems, Inc

Kebab™ Disc-type oil skimmer by Vikoma International Ltd

Keene Former equipment manufacturer acquired by Amwell, Inc

Kenics® Static mixer product line by Chemineer, Inc

Kenite® Diatomite material by Celite Corp

Ketema Product group of Baker Process/Ketema

Key-Pac Package water/wastewater treatment plants by Pacific Keystone ogies

Technol-Keystone Former name of Pacific Keystone Technologies

K-Floc™ Wastewater flocculant/coagulant by Kem-Tron

K-Floor Suspended monolithic filter floor by the former PWT Americas

kg See “kilogram (kg).”

kiln A heated enclosure for processing a substance by drying or burning

kiln dust See “cement kiln dust.”

kilocalorie See “calorie.”

kilogram (kg) A unit of mass equivalent to 1000 grams or approximately 2.205pounds

kilopascal (kPa) A unit of pressure equal to 1000 pascals, 0.3346 feet of hydraulichead, or 0.145 psi

kilowatt (kW) A measure of power equal to 1000 watts; 1 hp equals 0.746 kilowatts

kilowatt-hour (kWh) A unit of energy equal to that expended by 1 kilowatt in 1 hour

kinematic viscosity A fluid’s absolute viscosity divided by its mass density

kinesis An organism’s involuntary movement or reaction to an environmentalstimulus

kinetic energy Energy that is possessed by a body of matter as a result of itsmotion

kinetic head The theoretical vertical height that a liquid may reach due to itskinetic energy

KIWA Netherlands Waterworks Testing and Research Institute

Kiwi Centrifuge conveyor by Alfa Laval Separation, Inc

Kjeldahl nitrogen The sum of the organic plus ammonia nitrogen in a water sample

KL Series™ Cleaning powders for removal of membrane foulants by King LeeTechnologies

Klampress® Belt filter press by Ashbrook Corp (U.S.) and Simon-Hartley, Ltd.(U.K.)

Kleer Flow Spiral wound reverse osmosis membranes by Great Lakes tional, Inc

Interna-Klenphos-300 Zinc phosphate corrosion inhibitor by Klenzoid, Inc

Klensorb Oil and grease absorbent by Calgon Carbon Corp

Knight-Botec Auger compost mixer by Knight Manufacturing Corp

knot A unit of speed equal to one nautical mile per hour (approximately 1.15 mph)used to describe the speed of winds or ships

Koagulator Solids contact clarifier by USFilter/Zimpro

Koch Corrosion Control Former name of KCC Corrosion Control Co

KochKleen® Reverse osmosis cleaning chemicals by Koch Membrane Systems,Inc

KochTreat® Antiscalants, stabilizers, and anti-microbial chemicals by Koch brane Systems, Inc

Mem-Koflo® In-line static mixers by Koflo Corp

Komara™ Floating oil skimmer by Vikoma International Ltd

Kompakt Tubular block media by NSW Corp

Kompress® Belt filter press by Komline-Sanderson, Engineering Corp

Komprimat Fish/screenings separation system by Brackett Geiger

Konsolidator Wet scrubber solids filter by CMI-Schneible Co

Kopcke Former name of REKO Industrial Equipment B.V

Koppers Former manufacturer of traveling bridge filters whose product line wasacquired by Infilco Degremont, Inc

Koro-Z PVC biological filter media formerly offered by B.F Goodrich Co

kPa See “kilopascal (kPa).”

kraft An alkaline chemical pulping process using salt cake as makeup

Kraus-Fall Peripheral feed clarifier by Smith & Loveless, Inc.

krill A small, shrimp-like marine crustacean that is a major food source for whales,seals, and squid

Krüger Former name of USFilter/Krüger

Kruger/Fuchs Autothermal thermophilic aerobic digestion system by ter/Krüger

USFil-KUBE 3 Belt filter press by Klein America, Inc

kW See “kilowatt (kW).”

K-W Products Former equipment manufacturer acquired by Smith & Loveless, Inc

kWh See “kilowatt-hour (kWh).”

Kyoto Protocol A global agreement among 150 nations who met in Kyoto, Japan

in 1997 to discuss a comprehensive plan to reduce greenhouse gas emissions

in hopes of improving climatic conditions

L

L*ARO Reverse osmosis system by the former L*A Water Treatment Corp

L/d Liters per day

L/d ratio A simple parameter used to aid in sizing granular media filters based

on the bed depth and effective size of media

L-10 life See “B-10 life.”

La Niña A climatic cycle that results in what climatologists believe is the mostnormal wind, pressure, and current patterns in the tropics

LADD Lowest acceptable daily dose

LAER Lowest achievable emission rate

Lagco Parshall flume by F.B Leopold Co., Inc

lagoon An excavated basin or natural depression that contains water, wastewater,

or sludge

Lagoonerator™ Submerged, fine bubble aeration diffusion device by ter/Envirex

USFil-laid length The total length of a pipe or pipeline after it has been placed in position

lake A large, inland body of water, usually more than 200,000 square meters

Lake Aid Systems Former name of LAS International

Lakos IPC Self-cleaning pump intake screen by Claude Laval Corp

LAL test See “Limulus Amebocyte Lystate test (LAL test).”

lamel A thin plate

Lamella® Gravity settler/thickener using inclined plates by Parkson Corp

LamGard Automated oxygen control system by Gardner Denver Blower Division

laminar flow A flow situation in which fluid moves in smooth parallel layers withessentially no mixing or turbulence, usually with a Reynolds number less than2000

LAMP Lake Acidification Mitigation Project

Lam-Pak® Package treatment plant by Graver Co

Lamson Centrifugal blower products by Gardner Denver Blower Division.

Lanco Environmental™ Equipment product line of Waterlink Separations, Inc

Lancom™ Flue gas monitoring system by Land Combustion

Lancy™ Wastewater treatment product line offered by USFilter/Industrial water Systems

Waste-land application The disposal of wastewater or municipal solids onto land undercontrolled conditions

land ban RCRA provisions prohibiting land disposal of specific toxic materialsunless they meet applicable treatment standards

land disposal Application of municipal wastewater solids to the soil without duction of usable agricultural products

pro-Land Disposal Restrictions (LDR) EPA-promulgated rules implementing theland ban

landfarming Application of organic waste onto surface soil for the purpose ofcontrolled biodegradation

landfill (LF) A land disposal site that employs an engineering method of solidwaste disposal to minimize environmental hazards and protect the quality ofsurface and subsurface waters

Landox™ Aeration system by WesTech Engineering Inc (North America) andLandustrie Sneek BV

landscaping The enhancement of the appearance of land by changing its contoursand planting decorative vegetation

Landy™ Surface aerator product line by WesTech Engineering Inc (North ica) and Landustrie Sneek BV

Amer-Langelier Saturation Index (LSI) A measure of the degree of saturation of cium carbonate in water based on pH, alkalinity, and hardness A positive LSIindicates that calcium carbonate may precipitate from solution to form scale

cal-Lanpac® Packing media for air stripping towers by Lantec Products, Inc

lapse rate The rate at which temperature decreases as altitude increases

Laran® An anaerobic wastewater pretreatment process by Lotepro Corp (WesternHemisphere) and Linde-KCA-Dresden GmbH

large calorie (Cal) See “calorie.”

large dam Criteria established by ICOLD to categorize dams whose height

15 meters or more; or whose height is between 10-15 meters with a crest length

of at least 500 meters with a reservoir volume of at least 1 million cubic meters

large quantity generator Person or facility generating more than 1000 kilos (2200pounds) of hazardous waste per month and subject to all RCRA requirements

large water system A water system that serves more than 50,000 persons

large-quantity handlers (LQHs) Universal waste handlers who accumulate morethan 5000 kilograms of wastes

LAS See “linear alkyl sulfonate (LAS).”

Lasaire® Lagoon aeration system by A.B Marketech, Inc

latency period The time elapsing from the first exposure of a chemical until theappearance of a toxic effect

latent heat The heat required to cause a change of state at constant temperature,such as the vaporization of water or the melting of ice

lateral A secondary pipe that extends from a main water pipe or header.

Lateral Flow Sludge Thickener™ Gravity sludge thickener by Gravity Flow tems, Inc

Sys-lateral sewer A sewer which connects the collection main to the interceptor sewer

launder A trough used to transport water

laundering weir A v-notched overflow weir used to promote uniform flow rates

laundry wastes Wastewater from industrial laundries that may be characterized

by the presence of lint, fibers, oils, and greases

Lavasol™ Liquid reverse osmosis membrane cleaners by Professional Water nologies, Inc

Tech-LC (1) Lethal concentration (2) Liquid chromatography

LC 50 See “lethal concentration.”

LCL Lower control limit

LCR Lead and Copper Rule

LCRS Leachate collection and removal system

LD See “lethal dose.”

LD 50 See “lethal dose (LD).”

LDC London Dumping Convention

LDCRS Leachate detection, collection, and removal system

LDR See “Land Disposal Restrictions (LDR).”

LDS Leak detection system

leach field The area of land into which a septic tank drains or wastewater isdischarged

leachate Fluid which percolates through solid materials or wastes and containssuspended or dissolved materials or products of the solids

leachate collection system A system that gathers leachate and pumps it to thesurface for treatment

leaching The process by which soluble materials are washed out of soil, ore, orburied waste, and into a water source

lead A trace element and cumulative poison that may be inhaled or ingested infood or water Chemical formula is Pb

Leadtrak Test kits used to determine lead content of water by Hach Co

leaf filter A precoat filter with flat elements or leaves

leakage (1) The presence of an ionic species in an ion exchanger effluent thatusually indicates bed exhaustion (2) The uncontrolled loss of water from atank or aquifer

Leakwise® Oil on water monitoring systems by Agar Corp

L’eau Claire® Upflow filter products by USFilter/Whittier

Lectra/San Marine sanitation system by Exceltec International Corp

left bank The left hand bank of a river or stream when facing downstream

Legionella A genus of bacteria, some species of which have caused a type ofpneumonia called Legionnaires Disease

LEL See “lower explosive limit (LEL).”

Lemna® Biological wastewater treatment system utilizing aquatic duckweed byLemna Corp

Lemnaceae Floating aquatic plants that provide a habitat for aquatic organismscapable of metabolizing wastewater organics Also known as “duckweed.”

LemTec™ Biological wastewater treatment system and products by Lemna Corp

lentic water Standing or stagnant pond, swamp, or marsh water

Leo-Lite Fiberglass effluent and scum trough by F.B Leopold Co., Inc

Leopold® Water and wastewater treatment products by F.B Leopold Co., Inc

LeoVision PC-driven graphics display of treatment plant operating conditions byF.B Leopold Co., Inc

LEPA The designation for a low-energy, precision application irrigation sprinkler

lethal Causing, or being able to cause, death

lethal concentration The concentration of a substance which is fatal to a specifiedpercentage of the population, usually expressed at the 50% level as LC50

lethal dose (LD) The quantity of a substance which is fatal to a specified age of the population, usually expressed at the 50% level as LD50

percent-LEV Low emissions vehicle

levee A dike or embankment along a river built to prevent flooding of the rounding land

sur-Level Bed Agitator Agitator used in composting system by USFilter/CPC

Level Mate™ Level measurement instrument by Ametek, PMT Products

Level of Concern (LOC) The concentration in air of an extremely hazardoussubstance above which there may be serious immediate health effects to anyoneexposed for short periods

levigation The separation of fine particles from coarser ones by suspending them

in a liquid

Lewatit® Ion exchange resin by Bayer Corp

LF See “landfill (LF).”

LFG Landfill gas

LFL Lower flammability limit

LHW Liquid hazardous waste

LI See “Langelier Saturation Index (LSI).”

lichen A sponge-like plant growing on wood, stone, or soil which is formed by

an association of a fungus and alga, and often used as an air pollution indicatorspecies

life cycle cost A method of comparing costs of various alternatives which ers capital, operations, and maintenance costs

consid-Lifeserver™ Built-in-place wastewater treatment plants by USFilter/Davco

lifetime exposure Total amount of exposure to a substance which a human wouldreceive in a lifetime, usually assumed to be 70 years

Lift Screen Reciprocating rake bar screen by USFilter/Headworks Products

lift station A chamber that contains pumps, valves, and electrical equipment essary to pump water or wastewater

nec-ligand An atom, ion, or molecule bound to a central atom of a molecule to form

a complex

Lightspeed Digital fiber optic flowmeter by Newport Electronics

lignin An organic substance that forms the chief part of wood tissue

lignite A type of coal with a low energy content; also called “brown coal.”

LIMB Limestone-injection multistage burner

Limberflo Precast filter bottom system by USFilter/Aerator Products

lime The term generally used to describe ground limestone (calcium carbonate),hydrated lime (calcium hydroxide), or burned lime (calcium oxide)

lime kiln A unit used to calcine lime

lime recalcining Recovery of lime from water or wastewater sludge, usually with

a multiple hearth furnace

lime scale Scale formed by hard water containing a high percentage of calciumcarbonate

lime slaker A device used to hydrate quicklime

lime softening The addition of sufficient lime to raw water to achieve a reduction

limestone A sedimentary rock composed primarily of calcium carbonate

limestone scrubbing Use of a limestone and water solution to remove gaseousstack-pipe sulfur before it reaches the atmosphere

limit of detection (LOD) The minimum concentration that can be detected by ananalytical method Generally the same as “instrument detection limit.”

limnology The study of fresh water lakes and their flora and fauna

LIMS Laboratory information management system

Limulus Amebocyte Lystate test (LAL test) A test used to determine presence

of endotoxins in treated water, commonly used on water to be used for maceutical purposes

phar-lindane A pesticide that causes adverse health effects in domestic water suppliesand is toxic to freshwater fish and aquatic life

Lindox® A pure oxygen, activated sludge wastewater treatment process by LoteproCorp (Western Hemisphere) and Linde-KCA-Dresden GmbH

linear alkyl sulfonate (LAS) A family of chemical compounds widely used asdetergents, sometimes called “soft detergents” because they are readilydegraded to simpler substances by biological action

liner (1) A barrier of plastic, clay, or other impermeable material which preventsleachate from contacting surface or subsurface water (2) A protective, corro-sion resistant layer attached or bonded to the inside of a tank

Link-Belt® Environmental equipment product line by USFilter/Envirex

Linpor® An activated sludge wastewater treatment process by Lotepro Corp.(Western Hemisphere) and Linde-KCA-Dresden GmbH

LinX™ A spool valve used in reverse osmosis energy recovery devices by Desal

Co Ltd

lipids A group of organic compounds including fats that are water insoluble andimportant in the structure of cell walls and membranes

lipophilic Having an affinity for oil.

Liquaclone® Hydrocyclonic solids separation unit for removal of granular solidsfrom liquid discharges by Sanborn Environmental Systems

Liquapac™ Solids removal unit for spent coolant/oil clarification applications bySanborn Environmental Systems

liquefaction The process of making or converting a solid or gas to a liquid

Liqui/Jector® Liquid/gas coalescer by Osmonics, Inc

Liqui-Cel® Membrane contactors by Celgard LLC

liquid The state of matter between the solid and gaseous states in which matterpossesses a definite volume and flows freely but has no definite shape

Liquid A™ Sludge stabilization process by RDP Technologies, Inc

Liquid Carbonic Product line acquired by Praxair, Inc

liquid chlorine Chlorine compound that contains no water and results from eous chlorine under high pressure and which is stored in steel drums andcylinders

gas-liquid sludge Sludge which contains sufficient water flow by gravity or permitpumping

liquid-liquid extraction (LLE) See “solvent extraction.”

Liquid-Miser Activated carbon odor absorbers by Westport Environmental Systems

Liquidow® Calcium chloride products by Dow Chemical Co

LiquidPure Small, low-cost activated carbon drum adsorber by American NoritCompany, Inc

Liqui-Fuge™ Internally fed rotary fine screen by Vulcan Industries, Inc

LiQuilaz® In-line sensor for particle measurement by Particle Measuring Systems,Inc

Liquiphant Liquid level indicator by Endress+Hauser

Liqui-pHase® Carbon-dioxide neutralization system by Praxair, Inc

LiquiPro™ Metering pumps by Liquid Metronics, Inc

Liquipure Company acquired by USFilter/Lowell

Liqui-Strainer Externally fed rotating drum screen by Vulcan Industries, Inc

Liquitron® pH/ORP controllers by Liquid Metronics, Inc

liquor A aqueous solution of one or more chemical compounds

listed hazardous waste The designation for a waste material that appears on anEPA list of specific hazardous wastes or hazardous waste categories

liter (L) A unit of volume equal to 1000 cubic centimeters or 1.057 quarts Oneliter of water weighs 1000 grams Also called “litre.”

lithology The character or description of rocks in terms of their physical andchemical characteristics

lithosphere The solid portion of earth composed of rocks and soil

Litmustik® Pocket pH tester by Omega Engineering, Inc

litre See “liter (L).”

litter Solid waste or garbage from human activity deposited indiscriminately

Little Fox Modular wastewater treatment plant for marine applications by Red FoxEnvironmental, Inc

littoral zone The area of the shore line between high and low tides where rootedwater plants can grow

live bottom bin A storage bin in which controlled bottom discharge is facilitated

by a vibrating device or other mechanical mechanism

LLD Lower limit of detection Generally the same as “instrument detection limit.”

LLE Liquid-liquid extraction See “solvent extraction.”

LLL Low liquid level

LLQ Lower limit of quantitation Generally the same as “estimated quantitationlimit.”

LLW See “low-level radioactive waste (LLW).”

LME® Inclined plate separator by USFilter/Zimpro

LMI Liquid Metronics, Inc

LNG Liquefied natural gas

Lo/Pro™ Packaged odor control system by USFilter/RJ Environmental

Load Limitor Automatic chain tensioning system for traveling water screens byUSFilter/Rex & Link-Belt Products

loading rate The flow rate per unit area of treatment process through which waterflows

LOAEL See “lowest-observed-adverse-effect level (LOAEL).”

loam soil A rich soil consisting of organic material, sand, silt, and clay

Lobe-Aire® Rotary lobe blower by Spencer Turbine Co

Lobeflo™ Rotary lobe pump by MGI Pumps, Inc

Lobestar® Mixing eductor by Vortex Ventures

LOC See “Level of Concern (LOC).”

local ventilation The drawing off and replacement of contaminated air directlyfrom its source

localized corrosion Corrosion taking place at a relatively high speed in limitedsections of the area exposed to the corrosive medium

Lo-Cat® Hydrogen sulfide oxidation process for anaerobic bio-gas systems byUSFilter/Gas Technologies

loch A lake or narrow body of water surrounded by land and stretching to the sea(Scottish)

lock A short section of a canal equipped with gates at both ends so that the waterlevel can be changed to raise or lower boats from one level to another

LOD See “limit of detection (LOD).”

LOEL Lowest-observed-effect concentration

log boom A floating structure of logs or timber used to protect an intake, dam, orother structure by deflecting floating material

log reduction See “log removal.”

log removal A means of indicating the level of log10 removal, inactivation, or kill

of pathogenic organisms through physical-chemical treatment of water Forexample, 1-log removal equals a 90% reduction of the specified organism; a2-log reduction equals a 99% reduction; and a 3-log reduction equals a 99.9%reduction

log-death phase Bacterial growth phase where the microbe death rate exceeds theproduction of new cells

LogEasy™ Particle counter by Hach Co