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المعجم البيئي مشروع قيد العمل يحتاج ترجمة وإضافات


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  • 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 .lters based on the bed depth and effective size of media.
  • L-10 life See “B-10 life.”
  • La Ni.a A climatic cycle that results in what climatologists believe is the most normal wind, pressure, and current patterns in the tropics.
  • LADD Lowest acceptable daily dose.
  • LAER Lowest achievable emission rate.
  • Lagco Parshall .ume by F.B. Leopold Co., Inc.
  • lagoon An excavated basin or natural depression that contains water, wastewater, or sludge.
  • Lagoonerator™ Submerged, .ne bubble aeration diffusion device by USFil­ter/Envirex.
  • 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 .ow A .ow situation in which .uid moves in smooth parallel layers with essentially no mixing or turbulence, usually with a Reynolds number less than 2000.
  • LAMP Lake Acidi.cation 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 Waste­water Systems.
  • land application The disposal of wastewater or municipal solids onto land under controlled conditions.
  • land ban RCRA provisions prohibiting land disposal of speci.c toxic materials unless they meet applicable treatment standards.
  • land disposal Application of municipal wastewater solids to the soil without pro­duction of usable agricultural products.
  • Land Disposal Restrictions (LDR) EPA-promulgated rules implementing the land ban.
  • landfarming Application of organic waste onto surface soil for the purpose of controlled biodegradation.
  • land.ll (LF) A land disposal site that employs an engineering method of solid waste disposal to minimize environmental hazards and protect the quality of surface and subsurface waters.
  • Landox™ Aeration system by WesTech Engineering Inc. (North America) and Landustrie Sneek BV.
  • landscaping The enhancement of the appearance of land by changing its contours and planting decorative vegetation.
  • Landy™ Surface aerator product line by WesTech Engineering Inc. (North Amer­ica) and Landustrie Sneek BV.
  • Langelier Saturation Index (LSI) A measure of the degree of saturation of cal­cium carbonate in water based on pH, alkalinity, and hardness. A positive LSI indicates that calcium carbonate may precipitate from solution to form scale.
  • 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 (Western Hemisphere) 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 (2200 pounds) 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 more than 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 .rst exposure of a chemical until the appearance 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 Sys­tems, Inc.
  • 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 over.ow weir used to promote uniform .ow rates.
  • laundry wastes Wastewater from industrial laundries that may be characterized by the presence of lint, .bers, oils, and greases.
  • Lavasol™ Liquid reverse osmosis membrane cleaners by Professional Water Tech­nologies, Inc.
  • LC (1) Lethal concentration. (2) Liquid chromatography.
  • LC50 See “lethal concentration.”
  • LCL Lower control limit.
  • LCR Lead and Copper Rule.
  • LCRS Leachate collection and removal system.
  • LD See “lethal dose.”
  • LD50 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 .eld The area of land into which a septic tank drains or wastewater is discharged.
  • leachate Fluid which percolates through solid materials or wastes and contains suspended or dissolved materials or products of the solids.
  • leachate collection system A system that gathers leachate and pumps it to the surface for treatment.
  • leaching The process by which soluble materials are washed out of soil, ore, or buried waste, and into a water source.
  • lead A trace element and cumulative poison that may be inhaled or ingested in food or water. Chemical formula is Pb.
  • Leadtrak Test kits used to determine lead content of water by Hach Co.
  • leaf .lter A precoat .lter with .at elements or leaves.
  • leakage (1) The presence of an ionic species in an ion exchanger ef.uent that usually indicates bed exhaustion. (2) The uncontrolled loss of water from a tank or aquifer.
  • Leakwise® Oil on water monitoring systems by Agar Corp.
  • L’eau Claire® Up.ow .lter 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 of pneumonia called Legionnaires Disease.
  • LEL See “lower explosive limit (LEL).”
  • Lemna® Biological wastewater treatment system utilizing aquatic duckweed by Lemna Corp.
  • Lemnaceae Floating aquatic plants that provide a habitat for aquatic organisms capable 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 ef.uent 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 by
  • F.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 speci.ed
  • percentage of the population, usually expressed at the 50% level as LC50.
  • lethal dose (LD) The quantity of a substance which is fatal to a speci.ed percent­age of the population, usually expressed at the 50% level as LD50.
  • LEV Low emissions vehicle.
  • levee A dike or embankment along a river built to prevent .ooding of the sur­rounding land.
  • 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 hazardous substance above which there may be serious immediate health effects to anyone exposed for short periods.
  • levigation The separation of .ne particles from coarser ones by suspending them in a liquid.
  • Lewatit® Ion exchange resin by Bayer Corp.
  • LF See “land.ll (LF).”
  • LFG Land.ll gas.
  • LFL Lower .ammability 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 indicator species.
  • life cycle cost A method of comparing costs of various alternatives which consid­ers capital, operations, and maintenance costs.
  • Lifeserver™ Built-in-place wastewater treatment plants by USFilter/Davco.
  • lifetime exposure Total amount of exposure to a substance which a human would receive 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 nec­essary to pump water or wastewater.
  • ligand An atom, ion, or molecule bound to a central atom of a molecule to form
  • a complex. Lightspeed Digital .ber optic .owmeter 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.
  • Limber.o Precast .lter 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 calcium carbonate.
  • lime slaker A device used to hydrate quicklime.
  • lime softening The addition of suf.cient lime to raw water to achieve a reduction of carbonate hardness.
  • lime stabilization The addition of lime to untreated sludge to raise the pH to 12 for a minimum of 2 hours to chemically inactivate microorganisms.
  • lime-and-settle Common term for treatment technologies that utilize chemical precipitation and sedimentation processes.
  • lime-soda softening The addition of suf.cient lime and soda ash to raw water to achieve a reduction of carbonate and noncarbonate hardness.
  • limestone A sedimentary rock composed primarily of calcium carbonate.
  • limestone scrubbing Use of a limestone and water solution to remove gaseous stack-pipe sulfur before it reaches the atmosphere.
  • limit of detection (LOD) The minimum concentration that can be detected by an analytical method. Generally the same as “instrument detection limit.”
  • limnology The study of fresh water lakes and their .ora 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 phar­maceutical purposes.
  • lindane A pesticide that causes adverse health effects in domestic water supplies and is toxic to freshwater .sh and aquatic life.
  • Lindox® A pure oxygen, activated sludge wastewater treatment process by Lotepro Corp. (Western Hemisphere) and Linde-KCA-Dresden GmbH.
  • linear alkyl sulfonate (LAS) A family of chemical compounds widely used as detergents, sometimes called “soft detergents” because they are readily degraded to simpler substances by biological action.
  • liner (1) A barrier of plastic, clay, or other impermeable material which prevents leachate from contacting surface or subsurface water. (2) A protective, corro­sion 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 and important in the structure of cell walls and membranes.
  • lipophilic Having an af.nity for oil.
  • Liquaclone® Hydrocyclonic solids separation unit for removal of granular solids from liquid discharges by Sanborn Environmental Systems.
  • Liquapac™ Solids removal unit for spent coolant/oil clari.cation applications by Sanborn 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 matter possesses a de.nite volume and .ows freely but has no de.nite 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 gas­eous chlorine under high pressure and which is stored in steel drums and cylinders.
  • liquid sludge Sludge which contains suf.cient water .ow by gravity or permit pumping.
  • 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 Norit Company, Inc.
  • Liqui-Fuge™ Internally fed rotary .ne 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 an EPA list of speci.c hazardous wastes or hazardous waste categories.
  • liter (L) A unit of volume equal to 1000 cubic centimeters or 1.057 quarts. One liter of water weighs 1000 grams. Also called “litre.”
  • lithology The character or description of rocks in terms of their physical and chemical 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 Fox Environmental, Inc.
  • littoral zone The area of the shore line between high and low tides where rooted water 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 quantitation limit.”
  • LLW See “low-level radioactive waste (LLW).”
  • LME® Inclined plate separator by USFilter/Zimpro.
  • LMI Liquid Metronics, Inc.
  • LNG Lique.ed natural gas.
  • Lo/Pro™ Packaged odor control system by USFilter/RJ Environmental.
  • Load Limitor Automatic chain tensioning system for traveling water screens by USFilter/Rex & Link-Belt Products.
  • loading rate The .ow rate per unit area of treatment process through which water .ows.
  • 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.
  • Lobe.o™ 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 directly from its source.
  • localized corrosion Corrosion taking place at a relatively high speed in limited sections of the area exposed to the corrosive medium.
  • Lo-Cat® Hydrogen sul.de oxidation process for anaerobic bio-gas systems by USFilter/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 water level 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 .oating structure of logs or timber used to protect an intake, dam, or other structure by de.ecting .oating 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. For example, 1-log removal equals a 90% reduction of the speci.ed organism; a 2-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 the production of new cells.
  • LogEasy™ Particle counter by Hach Co.
  • log-growth phase Bacterial growth phase where cells divide at a rate determined by their generation time and their ability to process food.
  • Lo-Head™ Traveling bridge .lter by Agency Environmental, Inc.
  • Lo-Hi™ Low pressure, high intensity ultraviolet lamps by PCI-Wedeco Environ­mental Technologies, Inc.
  • LOI Loss on ignition.
  • long ton A unit of weight equal to 2240 pound.
  • Longopac Screenings bagging system by Spirac.
  • LoNox™ Combustion burner by John Zink Co.
  • LOOP Package wastewater treatment process using oxidation ditch process by Smith & Loveless, Inc.
  • Loop Chain Nonmetallic, .lament wound sludge collector chain by USFil­ter/Envirex.
  • Lo-Pro™ Air stripper by Geotech/ORS Environmental Systems.
  • LOQ Limit of quantitation. Generally the same as “estimated quantitation limit.”
  • loss of head A decrease in head energy that results from a bend, obstruction, or expansion in a channel or pipeline.
  • lotic water Rapidly .owing water of a river or stream.
  • Love Canal An industrial chemical waste site in Niagara Falls, NY which con­taminated a residential area and contributed to public furor resulting in the 1980 enactment of Superfund.
  • low NOx burners One of several combustion technologies used to reduce emis­sions of nitrogen oxides.
  • low sodium water Bottled water containing 140 mg or less of sodium per serving.
  • low sulfur coal See “compliance coal.”
  • lower explosive limit (LEL) The concentration of a compound in air below which the mixture will not catch on .re.
  • lowest-observed-adverse-effect level (LOAEL) The lowest dose of a substance to cause an increase in the frequency or severity of an adverse effect in an exposed population.
  • low-.ow toilet A toilet that uses no more than 1.6 gallons of water per .ush.
  • low-level radioactive waste (LLW) Wastes less hazardous than most of those associated with nuclear reactor, usually generated by hospitals, research lab­oratories, and certain industries.
  • LOX Liquid oxygen.
  • LP Block™ Low pro.le .lter underdrain by Tetra Process Technologies.
  • lpf Liters per .ush.
  • LPG Lique.ed petroleum gas.
  • LQG Large quantity generator.
  • LQHs See “large-quantity handlers (LQHs).”
  • LSC™ Package spray-type deaerating heater by Graver Co.
  • LSI See “Langelier Saturation Index (LSI).”
  • LSTK Lump sum turnkey.
  • LTA Low temperature additive.
  • LTESWTR Long-Term Enhanced Surface Water Treatment Rule.
  • LUFT Leaking underground fuel tank.
  • lumen (1) The bore or axial hole through the center of a hollow .ber membrane or tubular structure. (2) A unit of light measurement equal to the light given off in a unit solid angle from a uniform point source of one candela.
  • LUST Leaking underground storage tank.
  • LVHC Low volume, high concentration.
  • LWL Low water level.
  • LWT® Liquid Waste Technology, Inc.
  • LX Leachability index.
  • Lyco™ Wastewater treatment equipment product line by USFilter/Industrial Wastewater Systems.
  • Lynx® Chain driven bar screen by Waterlink Separations, Inc.
  • lyse To undergo lysis.
  • lysimeter A device used to measure or obtain samples of water draining through soil.
  • lysis The rupture of a cell that results in loss of its contents


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