Abatement Debr is. Waste from remediation activities. Abatement. Reducing the degree or intensity of, or eli minating, pollution. Absorbed Dose . In exposure assessment, the amount of a< /lex> substance that pen etrates an exposed organism's absorption barriers (e.g. ,, skin, lung tissue, gastrointestinal tract) through physical or biological processes.< /s> The term is synonymous with internal dose. Absorption Barrier . Any of the exchange sites of the body that permit uptake of various substance s at different rate s (e.g., skin, lung tissue, and gastro intestinal-tract wall) Absorption. The uptake of water , other fluids, or dissolved chemicals by a cell or an organism (as tree roots abs orb dissolved nutrients in soil.) Accident Site . The location of an un expected occurrence, failure or loss,< /lex> either at a plant or along a trans- port ation route, resul ting in a release of hazardous material s. Acclimatization. The physiological< /lex> and behavioral adju stments of an organi sm to changes in its environment.< /lex> Acid Aerosol. Acidic liquid or solid particles small enough to become airborne. High concentrations can irritate the lungs and have been associated with respiratory diseases like asthma. Acid Depositio n. A complex chemical and atmospheric phenomenon that occurs when emissions of sulfur and < lex pos=NN>nitrogen compounds and other substances are< /lex> transformed by chem ical processes in t he atmosphere, ofte n far from the original sources, and then deposited on earth in either wet or d ry form. The wet forms, popularly called "acid rain," can fall to< /lex> earth as rain< lex pos=",">, snow, or fog. The dry forms are acidic gases or particul- ates. Acid Mine Drainage. Drainage of water from areas that have been mined fo r coal or other mineral ores. The water has a low pH because of its contact with sulfur-bearing material and is harmful to aquatic organisms. Acid Neutralizing Capacity. < lex pos=NN>Measure of ability of a base (e.g., water or soil) to resist changes in pH. Acid Rain. < s>(See. acid deposition) Acidic. The condition of water or soil that contains a sufficient amount of acid substances to lower the pH below 7.0. Action Levels . 1. Regulatory levels recommended by EPA for enforce ment by FDA and USDA when pesticide residues occur in food or feed commodities for reasons other than the direct application of the pesti- cide. As o pposed to "tolera nces" which are< /lex> established for re sidues occurring as a direct result of< /lex> proper usage, action levels are set for inadvertent residues resulting fro m previous legal use or accidental conta mi- nation.< /s> 2. In the Superfund program, the existence of a contaminant concentration in the environment high enough to warr ant action or trigge r a response under SARA an d the Natio nal Oil and Hazardous Substances Contingency Plan. The term is also used in other regulatory prog rams. (See< /lex>. tolerances.) Activated Carbon< /lex>. A highly adsorbent form of carbon used to remove odors and toxic substances fro m liquid or gaseous< /lex> emissions. In waste treatment, it is used to remove dissolved organic matter from waste drinking water. It is also used in motor vehicle evaporative control systems. Activated Slu dge. Product that results when < lex pos=JJ>primary effluent is mixed with bacteria-laden< /lex> sludge and then agitated and aerated to promote biological treatment, speedi ng the breakdown of< /lex> organic matter in raw sewage undergoing secondary waste tre atment. Activator. A chemical added to a pes ticide to increase its activity. Active Ingredi ent. In any pesticide product, the component that kills, or otherwise controls, target pests. Pesticides are regulated primarily on the basis of active ingredients. Activity Plans. Written procedures in a school's asbestos-management plan that detail the steps a Lo cal Education A gency ( LEA) will follow in performing the initial and ad ditional cleaning, operation and maintenance-program tasks; periodic surveillance; and < lex pos=NN>reinspection required by the Asbestos Hazard< /lex> Emergency Response Act (AHE RA). Acute Exposure . A single exposure to a toxic substance w hich may result in severe biological har m or death. Acute exposures ar e usually characterized as lasting no longer than a day, as compared < lex pos=TO>to longer, continuing exposure over a period of time. Acute Toxicity . The ability of a subs tance to cause sever e biological harm or death soon after a single exposure or dose. < lex pos=RB>Also, any poisonous effect resulting from a single short-term exposure to a toxic substance. (See . chronic toxicity, toxicity.) Adaptation. Changes in an organism's physiological structure or function or habits that allow it to survive in new surroundings. Add-on Control Device. An air pollution control device such as carbon absorber or incinerator that reduces the pollution in an exhaust gas. The co ntrol device usually does not affect th e process being co ntrolled and thus i s "add-on" technology, as opposed to a scheme to control pollution through altering the basic process itself. Adequately Wet . Asbestos containing material that is sufficiently mixed< /lex> or penetrated with< /lex> liquid to prevent the release of < lex pos=NNS>particulates. Administered Dose. In exposure assessment, the amount of a substance given to a test subject (human or animal) to determine dose-response relationships . Since expo sure to chemicals is usually inadvertent, this quantity is often called pot ential dose. Administrative Order. A legal document signed by EPA directing an individua l, business, or other entity to take corrective action or refrain from an activity. It describes the violations and actions to be taken, and can be enforced in court. Such orders may be issued, for example, as a result of an administrative complaint wher eby the respondent is ordered to pay a penalty for < lex pos=NNS>violations of a statute. Administrative Order O n Consent. A legal agreement signed by EPA and an individual, business, or other entity through which the violator agrees to pay fo r correction of vio lations, take the required corrective o r cleanup actions, or refrain from an activity. It describes the actions to be taken, may be subject to a comment period, applies to civil actions, and can be enforced in court. Administrative Procedures Act. A law that spells out procedures and re quirements related to the promulgation of regulations. Administrative Record. All documents which EPA considered or relied on in selecting the resp onse action at a Superfund site, culminating in the record o f decision for remed ial action or, an action memorandum for removal actions. Adsorption. Removal of a pollutant from air or water by collecting the pollu tant on the surface< /lex> of a solid material; e.g., an advanced m ethod of treating w aste in which acti vated carbon removes organic matter from waste-water. Adulterants. C hemical impurities or substances that by law do not belon g in a food, or pesticide. Adulterated. 1< /lex>. Any pestici de whose strength or purity falls be low the quality sta ted on its label . 2.< /s> A food, feed, or pr oduct that contains illegal pesticide residues. Advanced Trea tment. A level of wastewater treatment more stringent than secondary treatment; requires an 85-percent reduction in conventional pollutant concentration or a significant reducti on in non- conventional pollutants. Sometimes called tertiary treatment. Advanced Wast ewater Treatment. Any treatment of sewage that goes beyond the secondary or biological water treatment stage and includes the removal of nutrients such as phosphorus and nitrogen and a high percentage of suspended solids. < s>(See primary, secondary treatment.) Adverse Effec ts Data. FIFRA requir es a pesticide regis trant to submit dat a to EPA on < lex pos=DT>any studies or other information regarding unreasonable adverse effects of a pestici de at any time after its registratio n. Advisory. A non-regulatory document that communicates risk information t o those who may have to make risk management decisions. Aerated Lagoo n. A holding and/or treatment pond that< /lex> speeds up the natural process of biological decomposition o f organic waste by stimulating the grow th and activity of bacteria that degrad e organic waste. Aeration. A process which promotes biological < lex pos=NN>degradation of organic matter in water. The process < lex pos=MD>may be passive (as when was te is exposed to air), or active (as< /lex> when a mixing or bubbling device introduces the air). Aeration Tank . A chamber used to in ject air into water< /lex>. Aerobic. Life or processes that require, or are not< /lex> destroyed by, the presence of oxygen. (See. anaerobic< lex pos=".">.) Aerobic Treatm ent. Process by which microbes decompose complex organic compounds in the presence of oxygen and use the liberated energy for reproduction and growth< lex pos=".">. (Such processes include extended< /lex> aeration, tricklin g filtration, and rotating biological contactors.) Aerosol. 1. Small droplets or particles suspended in the atmosphere, typically containing sulfur . They are usually emitted naturall y (e.g., in volcanic eruptions< lex pos=")">) and as the result of anthr opogenic (human) activities such as burning fossil fuel s. 2. The pressurized ga s used to propel substances out of a container. Aerosol. A finely divided material suspended in air or other gaseous environment. Affected Land fill. Under the Clean Air Act, landfills that meet criteria for capacity, age, and emissions rates set by the EPA. They ar e required to colle ct and combust t heir gas emissions . t Affected Public< /lex>. 1 .The people who live and/or work near a hazardous waste site. 2 . The human p opulation adversely impacted following exposure to a toxic pollutant < lex pos=IN>in food, water, air, or soil. Afterburner. In incinerator < lex pos=NN>technology, a burner located so that the combustion gases are made to pass through its flame in orde r to remove smoke and odors. It may be attached to or be separated from the incinerator proper. Age Tank. A tank used to store a chemical solution of known concentration< /lex> for feed to a chemical feeder. Also called a day tank. Agent. Any physical, chemical, or biological entity th at can be harmful to an organism(synonymous with stressor). Agent Orange< /lex>. A toxic herbicide and defoliant used in t he Vietnam conflict, containing 2,4,5-trichlorophen- oxyacetic acid (2,4,5-T) and 2-4 di chlorophenoxyacetic acid (2,4-D) with t race amounts of dio xin. Agricultural Pollution. Farming wastes, including< /lex> runoff and leaching< /lex> of pesticides and fertilizers; erosio n and dust from plowing; improper disposal of animal manure and carcasses; crop residues< lex pos=",">, and debris. Agroecosystem. Land used for crops, pasture, and live stock; the adjacent uncultivated land that supports other vegetation and wildlife; and the asso ciated atmosphere, the underlying soils, groundwater, a nd drainage networks. AHERA Designa ted Person (ADP). A person designated by a Local Education Agency to ensure that the AHERA requirements for asbestos management and abatement are properly implemented. Air Binding. Situation where air enters the filter media and harms both the filtration and b ackwash processes. Air Changes Per Hour (ACH). The movement of a volume of air in a given period of time; if a house has one air change per hour, it means that the air in the house will be replaced in a one-hour period. Air Cleaning< /lex>. Indoor-air quality-control strategy to remove various airbor ne particulates and/or gases from the air. Most common methods are particulate filtra tion, electrostatic precipitation, and gas sorption. Air Contamina nt. Any particulate matter, gas, or combi nation thereof, oth er than water vapor< /lex>. (See . air pollutant< /lex>.) Air Curtain. A m ethod of containing oil spills. Air bubbling through a perforated pipe causes an < lex pos=NN>upward water flow that slows the spread of oil . It can als o be used to stop fish from entering polluted water< lex pos=".">. Air Exchange< /lex> Rate. The rate at whi ch outside air repl aces indoor air in a given space< lex pos=".">. Air Gap . Open ve rtical gap or empty< /lex> space that separat es drinking water su pply to be protecte d from another water system in a < lex pos=NN>treatment plant or other location. < s>The open gap protects the drinking water from contamination by backflow or back siphonage. Air Handling< /lex> Unit. Equipment that includes a fan or b lower, heating and< /lex>/or cooling < lex pos=NNS>coils, regulator controls, condensate drain pans, and air filters. Air Mass. < lex pos=NNP>A large volume of air with certain meteorological or polluted characteristics--e.g., a < lex pos=NN>heat inversion or smogginess--while in one location. The characteristics can change as the air mass moves away. Air Monitorin g. (See. monitoring) Air/< ENAMEX TYPE=ORGANIZATION>Oil Table. The surfa ce between the vados e zone and ambient oil; the pressure of oil in the porous med ium is equal to atmospheric pressure.< /lex> Air Padding. Pumping dry air into a container to assist with the withdrawal of liquid or to force a liquefied gas such as chlorine out o f the container. Air Permeabil ity. Permeability of soil with respect to air. Important to the design of soil-gas surveys. Measured in darcys or centimeters-per-second. Air Plenum. Any space used to conve y air in a building, furnace, or structure. The space above a suspended ceiling is often used as an air plenum. Air Pollutant . Any substance in air that could, in high enough concentrati on, harm man< lex pos=",">, other animals, vegetation, or material. Pollutants may include almost any natural or artificial composition of airborne matter capable of being < lex pos=JJ>airborne. They may be in the form of sol id particles, liqu id droplets, gase s, or in combination thereof. Generally, they fall into two main groups. (1) th ose emitted directly from identifiable sources and (2) those produced in the air by interact ion between two or more primary pollutants, or b y reaction with norm al atmospheric constituents, with or w ithout photoactivation< /ENAMEX>. Exclusive of pollen, fog, and dust, which are of natural origin, about 100 contamin ants have been id entified. Air pollutants are often grouped in categories for ease in classification; some of he categories are. solids, sulfur compounds, volatile organic chemicals, particulate matter, nitrogen compounds, oxygen compounds , halogen compounds, < ENAMEX TYPE=ORGANIZATION>radioactive compound, and odors. < ENAMEX TYPE=ORGANIZATION>Air Pollution. The p resence of contaminants or pollutant substances in the air that interfere with human health or we lfare, or produce other harmful environ mental effects. Air Pollution Control Device. Mechanism or equipment that cleans emissions generated by< /lex> a source (e.g., an i ncinerator, industrial smokestack, or an automobile exhaust system) by remov ing pollutants that would otherwise be released to the at mosphere. 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. (See. episode, pollution.) Air Quality Control Region. Air Quality Standards. The level of pollutants prescribed by regulations that are not be exceeded during a given time in a defi ned area. Air Quality Criteria. The levels of pollution and lengths of exposure above which adverse health and welfare effects may occur. Air Sparging< /lex>. Injecting air or oxygen into an aquifer t o strip or flush volatile contaminants as air bubbles up through The ground water and is captured by a vapor extraction system. Air Stripping . A treatment system that removes volatile organic compounds (< lex pos=NNP>VOCs) from contaminated ground wate r or surface water by forcing an airstream through the water and causing the compounds to < lex pos=VB>evaporate. Air Toxics. Any air pollutant for w hich a national ambi ent air quality stan dard (NAAQ S) does n ot exist (i.e., excluding ozone , carbon monoxide, PM-10, sulfur dioxide, nit rogen oxide) that< /lex> may reasonably be anticipated to cause< /lex> cancer; respiratory , cardiovascular,< /lex> or developmental ef fects; reproductive dysfunctions, neurological disorders, heritable gene mutations, < lex pos=CC>or other serious or irreversible chronic or acute health effects in humans. Airborne Part iculates. Total suspended particulate ma tter found in the atmosphere as solid particles or liquid< /lex> droplets. C hemical composition of particulates varies widely< lex pos=",">, depending on location and time of year. Sources of airborne particulates include. dust, em issions from industrial processes, combustion products fr om the burning of wood and coal, combustion< /ENAMEX> products associated with motor vehicle or non-road engine ex hausts, and reacti ons to gases in the atmosphere.< /s> Airborne Rele ase. Release of any pollutant into the air . Alachlor. A herbicide, marketed under the trade name Lasso, used mainly to control weeds in co rn and soy- < lex pos=NN>bean fields. Alar . Trade name for daminozide, a pesticide that make s apples redder,< /lex> firmer, and less likely to drop off trees before growers are ready to pick them. It i s also used to a lesser extent < lex pos=IN>on peanuts, tart cherries, concord grapes, and other fruits.< /lex> Aldicarb. An insecticide sold under the trade name Temik. It is made from ethyl isocyanate. Algae. Simple rootless plants that grow in sunlit waters in proportion to the amount of avail able nutrients. They can affect water quality adversely by lowering the dissolved oxygen in the water. They are food f or fish and small aquatic animals. Algal Blooms< /lex>. Sudden spurts of algal growth, which ca n affect water quali ty adversely and ind icate poten- tially hazardous changes in local water chemi stry. Algicide. Substance or chemical used specifically to kill or control algae. Aliquot. A measured portion of a sam ple taken for analy sis. One or< /lex> more aliquots mak e up a sample< lex pos=".">. (See. duplicate.) Alkaline. The condition of water or s oil which contains a sufficient amount of alkali substance to raise the pH above 7.0. Alkalinity. The capacity of bases to neutralize acids. An example is lime added to lakes to decrease ac idity. Allergen. A substance that causes an allergic reaction in individuals sensitive to it. Alluvial. Relating to and/or sand deposited by flowin g water. Alternate Method. Any method of sampling and analyzing for a n air or water pollutant that is not a reference or equivalent method but that has been demonstrated in specific cases-to EPA's satisfa ction-to produce results adequate for compliance monitoring. Alternative C ompliance. A policy that allows < lex pos=NNS>facilities to choose among methods for achieving emission-reduction or risk-reduction instead of command-and control regulations that specif y standards and ho w to meet them. Use of a theoretical emissions bubble over a facility to cap the amount of p ollution emitted while allowing the company to choose where and how (within the facility) it complies.(See. < lex pos=NN>bubble, emissions < lex pos=NN>trading.) Alternative F uels. Substitutes for traditional liquid , oil-derived motor vehicle fuels like gasoline and diesel . Includes mixtures of alcohol -based fuels with g asoline, methanol, ethanol, compress ed natural gas, and others. Alternative R emedial Contract Strategy Contractors. Government contractors who provide project management and technical servic es to support remedi al response activities at National Priorities List sites. Ambient Air. Any unconfined portion of the atmosphere. open air, surrounding air. Ambient Air Quality Standards. (See. Criteria Pollutants and National Ambient Air Quality Standa rds.) Ambient Measu rement. A measurement of the concentration of a substance or pollutant within the immediate environs of an organism; taken to relate it to the amount of possible exposure. Ambient Mediu m. Material surrounding or contacting an organism (< lex pos=NN>e.g., outdoor air, indoor a ir, water, < lex pos=CC>or soil, through which chemicals or pollutants can reach the organism. (See . biological medium, environmental medium.) Ambient Tempe rature. Temperature of the surrounding air or other medium. Amprometric T itration. A way of measuring concentrations of certain substances in water using an electric current that flows during a chemical reaction. Anaerobic. A life or process that o ccurs in, or is not destroyed < lex pos=IN>by, the absence of oxygen.< /lex> Anaerobic Dec omposition. Reduction of the net energy level and change in chemical composition of organic matter caused by microorganisms in an oxygen-free environment. Animal Dander . Tiny scales of animal skin, a common indoor air pollutant. Animal Studi es. Investigations using animals as surrogates for human s with the expectati on that the results are pertinent to humans. Anisotropy. In hydrology, the conditions under which one or more hydraulic properties of an aquifer vary from a reference point. Annular Space , Annulus. The < lex pos=NN>space between two concentric tubes or casings, or between the casing and the borehole wall. Antagonism. Interference or < lex pos=NN>inhibition of the effect of one chemical by the a ction of another. Antarctic "Ozone Hole". Refers to the seasonal depl etion of ozone in the upper atmosphere above a large < lex pos=NN>area of Antarctica. (See. Ozone Hole.) Anti-Degradation Clause. Part of fe deral air quality an d water quality req uirements prohibiting deterioration where pollution lev els are above the legal limit. Anti-Microbial. An agent that kills microbes. Applicable or Relevant and Appropriate Requirements (ARARs). Any state or federal statute that pertains to protection of human life and the environment in addressing specific conditions or use of a particular cleanup technology at a Superfund site, Applied Dose. In ex posure assessment, the amount of a substance in contact with the primary absorption boundaries of< /lex> an organism ( e.g., skin, lung tissue,< /lex> gastrointestinal track) and available f or absorption. Aqueous Solub ility. The maximum concentration of a chemical that will dissolve in pure water at a reference temperature. Aqueous. Something made up of water . Aquifer. An underground geological formation, or group of formations, containing water. Are sources of groundwater for wells and springs. Aquifer Test< /lex>. A test to determine hy draulic properties of an aquifer. Aquitard. Geological formation that may contain groundwater but is not capable of transmitting significant quan tities of it under< /lex> normal hydraulic gr adients. May function as confining bed. Architectural Coatings. Coverings< /lex> such as paint and roof tar that are used on exteriors of buildings. Area of < lex pos=NNP>Review. I n the UIC program, th e area surrounding an injection well th at is reviewed dur ing the permitting process to determine if flow between aq uifers will be indu ced by the injection operation. Area Source. Any source of air pollution that is released over a relatively small area but which cannot be classified as a point so urce. Such sources may include vehicles and other small engines, sma ll businesses and h ousehold activities, or biogenic sources such as a forest that releases hyd rocarbons. Aromatics. A type of hydrocarbon, su ch as benzene or toluene, with a specific type of ring structure. Aromatics are sometimes added to gasoline in order to increase octane. Some aromatics < lex pos=VBP>are toxic. Arsenicals. P esticides containing arsenic. Artesian (Aquifer or Well).< /lex> Water held u nder pressure in por ous rock or soil confined by impermeabl e geo- logical formations. Asbestos. A mineral fiber that can pollute air < lex pos=CC>or water and cause cancer or asbestosis when inhaled. EPA has banned or severely restricted its use in manufactu ring and construction. Asbestos Abate ment. Procedures to control fiber release from asbestos-cont aining materials in a building or to remove them entirely< /lex>, including removal , encapsulation, repair, enclosure, encasement, < lex pos=CC>and opera- tions and maintenance programs. Asbestos Asses sment. In the asbestos-in-schools progra m, the evaluation of the physical condition and potential for damage of < lex pos=DT>all friable asbestos containing materials and thermal insulation systems. Asbestos Progr am Manager. A building owner< /lex> or designated representative who supervises< /lex> all aspects of the facility asbestos management and control program. Asbestos-Containing Waste Materials (ACWM). Mill ta ilings or any waste< /lex> that contains comm ercial asbestos and is generated by a< /lex> source covered by the Clean Air Act Asbestos NESHAPS. Asbestosis. A disease associated with inhalation of asbestos fibers . The disease makes breathing progr es- sively more difficult and can be fatal. Ash. The mineral cont ent of a product remaining after comple te combustion. Assay. A test for a specific chemical , microbe, < lex pos=CC>or effect. Assessment En dpoint. In ecological risk assessment, an explicit expression of the environmental value to be protected; includes both an ecological entity and specific attributed thereof. entity (e.g.,< /lex> salmon are a valued ecological entity< /lex>; reproduct ion and population maintenance--the attribute--form an assessment endpoint.) Assimilation. The ability of a body o f water to purify itself of pollutants . Assimilative Capacity. The < lex pos=NN>capacity of a natural body of water to receive w astewaters or toxic materials without deleterious < lex pos=NNS>effects and without damage to aquatic life or humans who consume the water. Association of Boards of Certifi cation. An international organization re presenting boards which certify the operators of waterworks and wastewater facilities.< /s> Attainment Ar ea. An area considered to have air quality as good as or better than the national ambient air < lex pos=NN>quality standards as defined in the Clean Air Act. An area may be an attainm ent area for one pollutant and a < lex pos=NN>non-attainment area for others. Attenuation. The process by which a compound is reduced in concentration over time, through a bsorption, adsorption, degradation, d ilution, and/or transformation. an also be < lex pos=DT>the decrease with distance of sight caused by attenuation < lex pos=IN>of light by particulate pollu tion. Attractant. A chemical or agent that lures insects or other pests by sti mulating their sense of smell. Attrition. Wearing or grinding down of a substance by f riction. Dust from such processes contributes to air pollution. Availability Session.< /lex> Informal meeting at a public loca tion where interested citizens can talk with EPA and state officials on a one-to-one basis. Available Chlo rine. A measure of the amount of chlorine a vailable in chlorinated lime, hypochlorite com- pounds, and other material s used as a < lex pos=NN>source of chlorine when compared with < lex pos=DT>that of liquid or gaseous chlorines. Avoided Cost. The cost a utility would incur to generate the next increment of electric capacity using its own resources; many landfill gas projects' buy back rates are based on avoid ed costs. ACScale Sound Level. A measurement of sound approximating the sensitivity of the human ear, used to note the intensity or annoyance< /lex> level of sounds.