For more information regarding environmental services and regulations, please follow the links below to websites which may be of interest to you:
United States Environmental Protection Agency
New York State Department of Conservation
State of New Jersey Department of Environmental Protection
New York City Department of Buildings
New York City Department of Environmental Protection
New York City Office of Environmental Remediation
Suffolk County, New York Department of Health Services
Nassau County, New York Fire Marshall
Nassau County, New York Health Department
Westchester County, New York Planning Department
Glossary of Terms
The following glossary is a compilation of key terms created by leading agencies in the Northeast region. These agencies provide key information that help inform professionals and customers on terminology that is essential to understanding regulatory policy and professional standards for all environmental specialty construction projects.
Glossary of Terms – From the U.S. Environmental Protection Agency (EPA)
- Abiotic- Not biotic; not formed by biologic processes.
- Absolute viscosity -A measure of a fluid’s resistance to tangential or shear stress. Units are usually given in centipoise. Also referred to as dynamic viscosity.
- Acid- A corrosive solution with a pH less than 7. Vinegar is a common weak acid; battery acid is much stronger.
- Actinomycetes- Any of numerous, generally filamentous, and often pathogenic, microorganisms resembling both bacteria and fungi.
- Activated sludge process- A sewage treatment process by which bacteria that feed on organic wastes are continuously circulated and put in contact with organic waste in the presence of oxygen to increase the rate of decomposition.
- Acute effect- An adverse effect on any living organism in which severe symptoms develop rapidly and often subside after the exposure stops.
- Acute toxicity- Adverse effects that result from a single dose or single exposure of a chemical; any poisonous effect produced within a short period of time, usually less than 96 hours. This term normally is used to describe effects in experimental animals.
- Advection- The process of transfer of fluids (vapors or liquid) through a geologic formation in response to a pressure gradient that may be caused by changes in barometric pressure, water table levels, wind fluctuations, or infiltration.
- Aeration- The process of bringing air into contact with a liquid (typically water), usually by bubbling air through the liquid, spraying the liquid into the air, allowing the liquid to cascade down a waterfall, or by mechanical agitation. Aeration serves to (1) strip dissolved gases from solution, and/or (2) oxygenate the liquid.
- Aerobic – A biological process that occurs in the presence of oxygen.
- Afterburner- An off-gas posttreatment unit for control of organic compounds by thermal oxidation. A typical afterburner is a refractory-lined shell providing enough residence time at sufficiently high temperature to destroy organic compounds in the off-gas stream.
- Aggregate- Coarse mineral material (e.g., sand, gravel) that is mixed with either cement to form concrete or tarry hydrocarbons to form asphalt.
- Agricultural waste- Poultry and livestock manure, and residual materials in liquid or solid form generated from the production and marketing of poultry, livestock, furbearing animals, and their products. Also includes grain, vegetable, and fruit harvest residue.
- Air quality standards- The level of selected pollutants set by law that may not be exceeded in outside air. Used to determine the amount of pollutants that may be emitted by industry.
- Algae- Chiefly aquatic, eucaryotic one-celled or multicellular plants without true stems, roots and leaves, that are typically autotrophic, photosynthetic, and contain chlorophyll. Algae are not typically found in groundwater.
- Aliphatic- Of or pertaining to a broad category of carbon compounds distinguished by a straight, or branched, open chain arrangement of the constituent carbon atoms. The carbon-carbon bonds may be either saturated or unsaturated. Alkanes, alkenes, and alkynes are aliphatic hydrocarbons.
- Alkalinity- Having the properties of a base with a pH of more than 7. A common alkaline is baking soda.
- Ambient- Any unconfined portion of the atmosphere; open air; outside surrounding air. And/or Surrounding; the surrounding environment and conditions.
- Anaerobic- A biological process which occurs in the absence of oxygen.
- Analog- In chemistry, a structural derivative of a parent compound.
- Anisotropic- The condition in which hydraulic properties of an aquifer are not equal when measured in all directions.
- Anoxic- Total deprivation of oxygen.
- Aqueous solubility- The extent to which a compound will dissolve in water. The log of solubility is generally inversely related to molecular weight.
- Aquifer- A geologic formation capable of transmitting significant quantities of groundwater under normal hydraulic gradients.
- Aquitard- A geologic formation that may contain groundwater but is not capable of transmitting significant quantities of groundwater under normal hydraulic gradients. In some situations aquitards may function as confining beds.
- Aromatic- Of or relating to organic compounds that resemble benzene in chemical behavior. These compounds are unsaturated and characterized by containing at least one 6-carbon benzene ring.
- Asbestos- A mineral fiber that can pollute air or water and cause cancer or asbestosis when inhaled. EPA has banned or severely restricted the use of asbestos in manufacturing and construction.
- Assimilative capacity – The ability of a natural body of water to receive wastewaters or toxic materials without harmful effects and without damage to aquatic life.
- Attenuation – The reduction or lessening in amount (e.g., a reduction in the amount of contaminants in a plume as it migrates away from the source).
- Atterberg limits- The moisture contents which define a soil’s liquid limit, plastic limit, and sticky limit.
- Autoignition temperature- The temperature at which a substance will spontaneously ignite.
- Autotrophic- Designating or typical of organisms that derive carbon for the manufacture of cell mass from inorganic carbon (carbon dioxide).
- Bacteria- Unicellular microorganisms that exist either as free-living organisms or as parasites and have a broad range of biochemical, and often pathogenic, properties. Bacteria can be grouped by form into five general categories: cocci (spherical), bacilli (rod-shaped), vibrio (curved rod-shaped), spirilla (spiral), and filamentous (thread-like).
- Bactericide- A pesticide used to control or destroy bacteria, typically in the home, schools, or on hospital equipment.
- Baghouse- A dust-collection chamber containing numerous permeable fabric filters through which the exhaust gases pass. Finer particulates entrained in the exhaust gas stream are collected in the filters for subsequent treatment/disposal.
- Benthic organism- Any of a diverse group of aquatic plants and animals that lives on the bottom of marine and fresh bodies of water. The presence or absence of certain benthic organisms can be used as an indicator of water quality.
- Bentonite- A colloidal clay, largely made up of the mineral sodium montmorillonite, a hydrated aluminum silicate. Because of its expansive property, bentonite is commonly used to provide a tight seal around a well casing.
- Berm- A sloped wall or embankment (typically constructed of earth, hay bales, or timber framing) used to prevent inflow or outflow of material into/from an area.
- Best available control technology- The application of the most advanced methods, systems, and techniques for eliminating or minimizing discharges and emissions on a case-by-case basis as determined by EPA. BACT represents an emission limit based on the maximum degree of reduction of each pollutant as described in regulations under the Clean Air Act (CAA). The determination of BACT takes into account energy, environmental, economic effects, and other costs.
- Best available technology economically achievable- Originally described under Section 304(b)(2)(B) of the Clean Water Act, this level of control is generally described as the best technology currently in use and includes controls on toxic pollutants.
- Best management practices- Procedures or controls other than effluent limitations to prevent or reduce pollution of surface water (includes runoff control, spill prevention, and operating procedures).
- Bioaccumulation/biomagnifications- A process where chemicals are retained in fatty body tissue and increase in concentration over time.
- Bioassay- A method used to determine the toxicity of specific chemical contaminants. A number of individuals of a sensitive species are placed in water containing specific concentrations of the contaminant for a specified period of time.
- Bioaugmentation- The introduction of cultured microorganisms into the subsurface environment for the purpose of enhancing bioremediation of organic contaminants. Generally the microorganisms are selected for their ability to degrade the organic compounds present at the remediation site. The culture can be either an isolated genus or a mix of more han one genera. Nutrients are usually also blended with the aqueous solution containing the microbes to serve as a carrier and dispersant. The liquid is introduced into the subsurface under natural conditions (gravity fed) or injected under pressure.
- Bioavailability- The availability of a compound for biodegradation, influenced by the compound’s location relative to microorganisms and its ability to dissolve in water.
- Biochemical oxygen demand- A measure of the oxygen required to break down organic materials in water. Higher organic loads require larger amounts of oxygen and may reduce the amount of oxygen available for fish and aquatic life below acceptable levels.
- Biochemicals- Chemicals that are either naturally occurring or identical to naturally occurring substances. Examples include hormones, pheromones, and enzymes. Biochemicals function as pesticides through non-toxic, non-lethal modes of action, such as disrupting the mating pattern of insects, regulating growth, or acting as repellants. Biochemicals tend to be environmentally compatible and are thus important to Integrated Pest Management programs.
- Biocide- A substance capable of destroying (killing) living organisms.
- Biodegradability potential- The relative ease with which petroleum hydrocarbons will degrade as the result of biological metabolism. Although virtually all petroleum hydrocarbons are biodegradable, biodegradability is highly variable and dependent somewhat on the type of hydrocarbon. In general, biodegradability increases with increasing solubility; solubility is inversely proportional to molecular weight.
- Biodegradable- The ability of a substance to be broken down physically and/or chemically by microorganisms. For example, many chemicals, food scraps, cotton, wool, and paper are bio-degradable; plastics and polyester generally are not.
- Biodegradation- A process by which microbial organisms transform or alter (through metabolic or enzymatic action) the structure of chemicals introduced into the environment.
- Biodegradation potential- The relative ease with which petroleum hydrocarbons will degrade as the result of biological metabolism. Although virtually all petroleum hydrocarbons are biodegradable, biodegradability is highly variable and dependent somewhat on the type of hydrocarbon. In general, biodegradability increases with increasing solubility; solubility is inversely proportional to molecular weight.
- Biodiversity- The number and variety of different organisms in the ecological complexes in which they naturally occur. Organisms are organized at many levels, ranging from complete ecosystems to the biochemical structures that are the molecular basis of heredity. Thus, the term encompasses different ecosystems, species, and genes that must be present for a healthy environment. A large number of species must characterize the food chain, representing multiple predator-prey relationships.
- Biological pesticides- Certain microorganisms, including bacteria, fungi, viruses, and protozoa that are effective in controlling target pests. These agents usually do not have toxic effects on animals and people and do not leave toxic or persistent chemical residues in the environment.
- Biomass- The amount of living matter in a given area or volume.
- Biota- All living organisms in a given area.
- Boiling point- The temperature at which a component’s vapor pressure equals atmospheric pressure. Boiling point is a relative indicator of volatility and generally increases with increasing molecular weight.
- British Thermal Unit (BTU)- The quantity of heat required to raise the temperature of one pound of water one degree Fahrenheit at 39 degrees F; used as the standard for the comparison of heating values of fuels.
- Bubble radius- The maximum radial distance away from a biosparging well where the effects of sparging are observable. Analogous to radius of influence of an air sparging well.
- Bulk density- The amount of mass of a soil per unit volume of soil; where mass is measured after all water has been extracted and total volume includes the volume of the soil itself and the volume of air space (voids) between the soil grains.
- Butterfly valve- A shut-off valve usually found in larger pipe sizes (4 inches or greater). This type of valve can be used for non-critical flow control.
- By-product- Materials, other than the intended product, generated as a result of an industrial process.
- Chemotrophs- Organisms that obtain energy from oxidation or reduction of inorganic or organic matter.
- Chlorination- Adding chlorine to water or wastewater, generally for the purpose of disinfection, but frequently for accomplishing other biological or chemical results. Chlorine also is used almost universally in manufacturing processes, particularly for the plastics industry.
- Chlorofluorocarbons- A family of chemicals commonly used in air conditioners and refrigerators as coolants and also as solvents and aerosol propellants. CFCs drift into the upper atmosphere where their chlorine components destroy ozone. CFCs are thought to be a major cause of the ozone hole over Antarctica.
- Chronic effect- An adverse effect on any living organism in which symptoms develop slowly over a long period of time or recur frequently. Clear cut -Harvesting all the trees in one area at one time, a practice that destroys vital habitat and biodiversity and encourages rainfall or snowmelt runoff, erosion, sedimentation of streams and lakes, and flooding.
- Climate change – This term is commonly used interchangeably with “global warming” and “the greenhouse effect,” but is a more descriptive term. Climate change refers to the buildup of man-made gases in the atmosphere that trap the sun’s heat, causing changes in weather patterns on a global scale. The effects include changes in rainfall patterns, sea level rise, potential droughts, habitat loss, and heat stress. The greenhouse gases of most concern are carbon dioxide, methane, and nitrous oxides. If these gases in our atmosphere double, the earth could warm up by 1.5 to 4.5 degrees by the year 2050, with changes in global precipitation having the greatest consequences.
- Cloning- In biotechnology, obtaining a group of genetically identical cells from a single cell; making identical copies of a gene.
- Closure- The procedure an operator must go through when a landfill reaches the legal capacity for solid waste. No more waste can be accepted and a cap usually is placed over the site. The cap is then planted with grasses and other ground covers.
- Code of Federal Regulations- A periodic publication of the regulations established by U.S. law.
- Cometabolism- The simultaneous metabolism of two compounds, in which the degradation of the second compound(the secondary substrate) depends on the presence of the first compound (the primary substrate). For example, in the process of degrading methane, some bacteria can degrade hazardous chlorinated solvents that they would otherwise be unable to attack.
- Commercial waste management facility- A treatment, storage, disposal, or transfer facility that accepts wastes from a variety of sources for profit. A commercial facility manages a broader spectrum of wastes than a private facility, which normally manages a limited volume or type of waste.
- Community relations- Two-way communications with the public to foster understanding of EPA programs and actions and to increase citizen input into EPA decisions. Specific community relations activities such as holding public meetings and comment periods and opening information repositories are required at Superfund sites.
- Complexation- A reaction in which a metal ion and one or more anionic ligands chemically bond. Complexes often prevent the precipitation of metals.
- Compost- Decomposed organic material that is produced when bacteria in soil break down garbage and biodegradable trash, making organic fertilizer. Making compost requires turning and mixing and exposing the materials to air. Gardeners and farmers use compost for soil enrichment.
- Condensate- The liquid that separates from a vapor during condensation.
- Conditionally exempt generators- Small quantity facilities that produce fewer than 220 pounds of hazardous waste per month. Exempt from most regulations, conditionally exempt generators are required to determine whether their waste is hazardous and to notify local waste management agencies. These generators may treat or dispose of the waste on site or ensure that the waste is sent to a permitted disposal or recycling facility.
- Conductivity- A coefficient of proportionality describing the rate at which a fluid (e.g., water or gas) can move through a permeable medium. Conductivity is a function of both the intrinsic permeability of the porous medium and the kinematic viscosity of the fluid which flows through it.
- Cone of depression- The area around a discharging well where the hydraulic head (potentiometric surface) in the aquifer has been lowered by pumping. In an unconfined aquifer, the cone of depression is a cone-shaped depression in the water table where the media has actually been dewatered.
- Confined aquifer- A fully saturated aquifer overlain by a confining layer. The potentiometric surface (hydraulic head) of the water in a confined aquifer is at an elevation that is equal to or higher than the base of the overlying confining layer. Discharging wells in a confined aquifer lower the potentiometric surface which forms a cone of depression, but the saturated media is not dewatered.
- Confining layer- A geologic formation characterized by low permeability that inhibits the flow of water.
- Consent decree- A legal document submitted by the Department of Justice on behalf of the EPA for approval by a federal judge to settle a case. A consent decree can be used to formalize an agreement reached between EPA and potentially responsible parties (PRPs) for cleanup at a Superfund site.
- Conservation- Preserving and renewing natural resources to assure their highest economic or social benefit over the longest period of time. Clean rivers and lakes, wilderness areas, a diverse wildlife population, healthy soil, and clean air are natural resources worth conserving for future generations.
- Conservative- In the case of a contaminant, one that does not degrade and the movement of which is not retarded; is unreactive. (b) in the case of an assumption, one that leads to a worst-case scenario, one that is most protective of human health and the environment.
- Constituent- An essential part or component of a system or group (e.g., an ingredient of a chemical mixture). For instance, benzene is one constituent of gasoline.
- Corrosive- A substance that eats or wears away materials gradually by chemical action.
- County emergency operations plan -A plan required by Federal Emergency Management Agency regulations that describes actions the county will take to respond to emergency situations such as natural disasters, major fires, transportation incidents, or chemical releases.
- Covered facility -A facility having one or more of the 366+ extremely hazardous substances in amounts higher than the quantity designated by EPCRA. These facilities must file reports with the SERC and LEPC.
- Criteria- Descriptive factors taken into account by EPA in setting standards for pollutants. For example, water quality criteria describe the concentration of pollutants that most fish can be exposed to for an hour without showing acute effects.
- Cross-Cutter Federal Laws and Executive Orders- Federal statues and implementing regulations that address the federal responsibility for protecting and conserving environmental resources. Typically, cross-cutters apply to all construction projects receiving federal funds, regardless of the agency providing those funds.
- Cumulative Impacts- The impact on the environment that results from the incremental impact of the action when added to other past, present, and reasonably foreseeable future actions regardless of what agency (federal or non-federal) or person undertakes such actions. Cumulative impacts can result from individually minor but collectively significant actions taking place over time. See 40 C.F.R. ¿ 1508.7.
- Cyclone-A type of separator for removal of larger particles from an exhaust gas stream. Gas laden with particulates enters the cyclone and is directed to flow in a spiral causing the entrained particulates to fall out and collect at the bottom. The gas exits near the top of the cyclone.
- Darcy’s Law- An empirical relationship between hydraulic gradient and the viscous flow of water in the saturated zone of a porous medium under conditions of laminar flow. The flux of vapors through the voids of the vadose zone can be related to a pressure gradient through the air permeability by Darcy’s Law.
- Dechlorination- Removal of chlorine and chemical replacement with hydrogen or hydroxide ions to detoxify a substance.
- Deep well injection- A process by which waste fluids are injected deep below the surface of the earth.
- Degradation potential- The degree to which a substance is likely to be reduced to a simpler form by bacterial activity.
- Delist- Use of the petition process (1) to have a chemical’s toxic designation rescinded; (2) to remove a site from the National Priority List; or (3) to exclude a particular waste from regulation even though it is a listed hazardous waste.
- Denitrification- Bacterial reduction of nitrite to gaseous nitrogen under anaerobic conditions.
- Density- The amount of mass per unit volume.
- Diffusion- The process by which molecules in a single phase equilibrate to a zero concentration gradient by random molecular motion (Brownian motion). The flux of molecules is from regions of high concentration to low concentration and is governed by Fick’s Second Law.
- Direct Effects- Direct effects are “caused by the action and occur at the same time and place” (40 C.F.R. ¿ 1508.8) and are directly related to the project activity.
- Discharge- The release of any waste into the environment from a point source. Usually refers to the release of a liquid waste into a body of water through an outlet such as a pipe, but also refers to air emissions.
- Discharge area- An area of land where there is a net annual transfer of water from the ground water to surface water, such as to streams, springs, lakes, and wetlands.
- Dispersion- TSDFs that were already in operation when the RCRA standards were established, and that are operating under less stringent standards until they receive a permit.
- Dispersion model- A mathematical prediction of how pollutants from a discharge or emission source will be distributed in the surrounding environment under given conditions of wind, temperature, humidity, and other environmental factors.
- Disposal- The discharge, deposit, injection, dumping, spilling, leaking, or placing of any solid waste or hazardous waste into the environment (land, surface water, ground water, and air).
- Disposal facility- A landfill, incinerator, or other facility which receives waste for disposal. The facility may have one or many disposal methods available for use. Does not include wastewater treatment.
- Dissolution- Dissolving of a substance in a liquid solvent (e.g., water).
- Dissolved oxygen- Oxygen that is freely available in water to sustain the lives of fish and other aquatic organisms.
- Dose- In terms of monitoring exposure levels, the amount of a toxic substance taken into the body over a given period of time.
- Dose response- How an organism’s response to a toxic substance changes as its overall exposure to the substance changes. For example, a small dose of carbon monoxide may cause drowsiness; a large dose can be fatal.
- Downgradient- In the direction of decreasing static head (potential).
- Drawdown- Lowering the water table due to withdrawal of groundwater as from a well.
- Dump- A land site where wastes are discarded in a disorderly or haphazard fashion without regard to protecting the environment. Uncontrolled dumping is an indiscriminate and illegal form of waste disposal. Problems associated with dumps include multiplication of disease-carrying organisms and pests, fires, air and water pollution, unsightliness, loss of habitat, and personal injury.
- Dynamic viscosity- A measure of a fluid’s resistance to tangential or shear stress.
- Ecology- The study of the relationships between all living organisms and the environment, especially the totality or pattern of interactions; a view that includes all plant and animal species and their unique contributions to a particular habitat.
- Ecosystem- The interacting synergism of all living organisms in a particular environment; every plant, insect, aquatic animal, bird, or land species that forms a complex web of interdependency. An action taken at any level in the food chain, use of a pesticide for example, has a potential domino effect on every other occupant of that system.
- Effective porosity- The amount of interconnected pore space in a soil or rock through which fluids can pass, expressed as a percent of bulk volume. Some of the voids and pores in a rock or soil will be filled with static fluid or other material, so that effective porosity is always less than total porosity.
- Effluent- Something that flows out, especially a liquid or gaseous waste stream.
- Effluent Waste- water discharged from a point source, such as a pipe.
- Effluent limitations- Limits on the amounts of pollutants which may be discharged by a facility; these limits are calculated so that water quality standards will not be violated even at low stream flows.
- Electron acceptor- A chemical entity that accepts electrons transferred to it from another compound. It is an oxidizing agent that, by virtue of its accepting electrons, is itself reduced in the process.
- Electron donor- A chemical entity that donates electrons to another compound. It is a reducing agent that, by virtue of its donating electrons, is itself oxidized in the process.
- Emergency and Hazardous Chemical Inventory- An annual report by facilities having one or more extremely hazardous substances or hazardous chemicals above certain weight limits, as specified in Section 311 and 312 of EPCRA.
- Emergency Broadcasting System- Used to inform the public about an emergency and the protective actions to take. The EBS is a service of local radio and television stations, activated as needed and approved by a local emergency management agency.
- Emergency Preparedness Coordinator- The local government official designated to be notified immediately of chemical emergencies (e.g., spills, chemical releases, explosions, or fires) under EPCRA.
- Emission- The release or discharge of a substance into the environment. Generally refers to the release of gases or particulates into the air.
- Emission standards- Government standards that establish limits on discharges of pollutants into the environment (usually in reference to air).
- Empirical- Relying upon or gained from experiment or observation.
- Energy recovery- To capture energy from waste through any of a variety of processes (e.g., burning). Many new technology incinerators are waste-to-energy recovery units.
- Entrained- Particulates or vapor transported along with flowing gas or liquid.
- Environmental assessment- A preliminary, written, environmental analysis required by NEPA (see the Federal Law section) to determine whether a federal activity such as building airports or highways would significantly affect the environment; may require preparation of more detailed Environmental Impact Statement.
- Environmental Assessment (EA)- A concise public document prepared to provide sufficient data and analysis to determine whether to prepare an Environmental Impact Statement (EIS) or Finding of No Significant Impact (FONSI). See 40 C.F.R. ¿ 1508.9.
- Environmental audit- An independent assessment (not conducted by EPA) of a facility’s compliance policies, practices, and controls. Many pollution prevention initiatives require an audit to determine where wastes may be reduced or eliminated or energy conserved. Many supplemental environmental projects that offset a penalty use audits to identify ways to reduce the harmful effects of a violation.
- Environmental impact statement- A document prepared by or for EPA which identifies and analyzes, in detail, environmental impacts of a proposed action. As a tool for decision-making, the EIS describes positive and negative effects and lists alternatives for an undertaking, such as development of a wilderness area.
- Environmental Impact Statement (EIS)- A detailed document prepared to analyze federal actions that are likely to have a significant impact on the environment. An EIS provides the public and decision makers with detailed information and analyses of the environmental impacts of the proposed project. See 40 C.F.R. Part 1502.1
- Environmental Information Document (EID)- A written analysis prepared by the applicant that provides sufficient information for the Responsible Official to undertake an environmental review and prepare either an Environmental Assessment (EA) and Finding of No Significant Impact (FONSI) or an Environmental Impact Statement (EIS) and Record of Decision (ROD) for the proposed action. An EID includes basic project information, including a description of the proposed project, and evaluates the environmental impacts of the project and alternatives to the proposed project. See 40 C.F.R. ¿ 6.102(b)(4)
- Environmental justice- The fair treatment of people of all races, cultures, incomes, and educational levels with respect to the development and enforcement of environmental laws, regulations, and policies. Fair treatment implies that no population should be forced to shoulder a disproportionate share of exposure to the negative effects of pollution due to lack of political or economic strength.
- Environmental response team- EPA’s group of highly trained scientists and engineers based in Edison, NJ and Cincinnati, OH who back up the federal On-Scene Coordinator. The ERT’s capabilities include multimedia sampling and analysis, hazard assessment, hazardous substance and oil spill cleanup techniques, and technical support.
- Enzyme- Any of numerous proteins or conjugated proteins produced by living organisms and functioning as biochemical catalysts. (b) a protein that a living organism uses in the process of degrading a specific compound. The protein serves as a catalyst in the compound’s biochemical transformation.
- Epidemiologist- A medical scientist who studies the various factors involved in the incidence, distribution, and control of disease in a population.
- Estuary- A complex ecosystem between a river and near-shore ocean waters where fresh and salt water mix. These brackish areas include bays, mouths of rivers, salt marshes, wetlands, and lagoons and are influenced by tides and currents. Estuaries provide valuable habitat for marine animals, birds, and other wildlife.
- Eucaryotes- An organism having one or more cells with well-defined nuclei.
- Evaporation- The process by which a liquid enters the vapor (gas) phase.
- Ex situ- Moved from its original place; excavated; removed or recovered from the subsurface.
- Exposure- Radiation or pollutants that come into contact with the body and present a potential health threat. The most common routes of exposure are through the skin, mouth, or by inhalation.
- Extraction well- A well employed to extract fluids (either water, gas, free product, or a combination of these) from the subsurface. Extraction is usually accomplished by either a pump located within the well or suction created by a vacuum pump at the ground surface.
- Extraordinary Circumstances- Those circumstances that may cause a significant environmental effect such that a proposed action that otherwise meets the requirements of a categorical exclusion may not be categorically excluded. See 40 C.F.R. ¿ 6.204.
- Extremely hazardous substances- Any of 366 (+ or -) chemicals or hazardous substances identified by EPA on the basis of hazard or toxicity and listed under EPCRA. The list is periodically revised.
- Facultative- Used to describe organisms that are able to grow in either the presence or absence of a specific environmental factor (e.g., oxygen).
- Facultative anaerobes- Microorganisms that can grow in either the presence or the absence of molecular oxygen. In the absence of oxygen these microorganism can utilize another compound (e.g., sulfate or nitrate) as a terminal electron acceptor.
- Feedstock- Raw material supplied to a machine or processing plant from which other products can be made. For example, polyvinyl chloride and polyethylene are raw chemicals used to produce plastic tiles, mats, fenders, cushions, and traffic cones.
- Fick’s First Law- An equation describing the rate at which a gas transfers into solution. The change in concentration of gas in solution is proportional to the product of an overall mass transfer coefficient and the concentration gradient.
- Fick’s Second Law- An equation relating the change of concentration with time due to diffusion to the change in concentration gradient with distance from the source of concentration.
- Field capacity- The maximum amount of water that a soil can retain after excess water from saturated conditions has been drained by the force of gravity.
- Financial assurance- A means (such as insurance, guarantee, surety bond, letter of credit, or qualification as a self-insurer) by the operator of a facility such as a landfill to assure financial capability for cleaning up possible environmental releases and closure of that facility.
- Finding of No Significant Impact (FONSI)- A document briefly providing the reasons why a proposed action will not have a significant impact on the environment and for which an Environmental Impact Statement (EIS) will not be prepared.
- First draw- The water that comes out when a faucet in the kitchen or bathroom is first opened, which is likely to have the highest level of lead contamination from old plumbing solder and pipes.
- Flare- A device that burns gaseous materials to prevent them from being released into the environment. Flares may operate continuously or intermittently and are usually found on top of a stack. Flares also burn off methane gas in a landfill.
- Floodplain- Mostly level land along rivers and streams that may be submerged by floodwater. A 100-year floodplain is an area which can be expected to flood once in every 100 years.
- Flow Tube- A calibrated flow measuring device made for a specific range of flow velocities and fluids.
- flue gas desulfurization- The removal of sulfur oxides from exhaust gases of a boiler or industrial process; usually a wet scrubbing operation which concentrates hazardous materials in a slurry, requiring proper disposal.
- Flux – The rate of movement of mass through a unit cross-sectional area per unit time in response to a concentration gradient or some advective force.
- Free product- A petroleum hydrocarbon in the liquid (“free” or non-aqueous) phase.
- Fugitive emissions- Air pollutants released to the air other than those from stacks or vents; typically small releases from leaks in plant equipment such as valves, pump seals, flanges, sampling connections, etc.
- Fungicide- A pesticide used to control or destroy fungi on food or grain crops.
- Generator – A facility or mobile source that emits pollutants into the air; any person who produces a hazardous waste that is listed by EPA and therefore subject to regulation.
- Grab sample- A single sample of soil or of water taken without regard to time or flow.
- Gradient- The rate of change in value of a physical or chemical parameter per unit change in position. For example, hydraulic gradient is equal to the difference in head measured at two points (usually wells) divided by the distance separating the two points. The dimensions of head and distance are both lengths, therefore the gradient is expressed as a dimensionless ratio (L/L).
- ground water- Water found below the surface of the land, usually in porous rock formations. Ground water is the source of water found in wells and springs and is used frequently for drinking.
- Groundwater- The water contained in the pore spaces of saturated geologic media.
- Grout- A watery mixture of cement (and commonly bentonite) without aggregate that is used to seal the annular space around well casings to prevent infiltration of water or short-circuiting of vapor flow.
- Hazardous waste- A subset of solid wastes that pose substantial or potential threats to public health or the environment and meet any of the following criteria: -is specifically listed as a hazardous waste by EPA; – exhibits one or more of the characteristics of hazardous wastes (ignitability, corrosiveness, reactivity, and/or toxicity); – is generated by the treatment of hazardous waste; or is contained in a hazardous waste.
- Hazardous waste landfill- A specially permitted, excavated or engineered area in which hazardous waste is deposited and covered. Proper protection of the environment from the materials to be deposited in such a landfill requires careful site selection, the cataloging of types of wastes, good design (including a liner and a leachate collection and treatment system), proper operation, and thorough final closure.
- Health assessment- An evaluation of available data on existing or potential risks posed by a Superfund site. Every site on the National Priorities List has a health assessment prepared by the Agency for Toxic Substances and Disease Registry.
- Heat capacity- The quantity of energy that must be supplied to raise the temperature of a substance. For contaminated soils heat capacity is the quantity of energy that must be added to the soil to volatilize organic components. The typical range of heat capacity of soils is relatively narrow, therefore variations are not likely to have a major impact on application of a thermal desorption process.
- Heavy metal- A common hazardous waste; can damage organisms at low concentrations and tends to accumulate in the food chain.
- Henry’s law- The relationship between the partial pressure of a compound and the equilibrium concentration in the liquid through a proportionality constant known as the Henry’s Law Constant.
- Henry’s law constant- The ratio of the concentration of a compound in air (or vapor) to the concentration of the compound in water under equilibrium conditions.
- Herbicide- A pesticide designed to control or kill plants, weeds, or grasses. Almost 70% of all pesticide used by farmers and ranchers are herbicides. These chemicals have wide- ranging effects on non-target species (other than those the pesticide is meant to control).
- Heterogeneous- Varying in structure or composition at different locations in space.
- Heterotrophic- Designating or typical of organisms that derive carbon for the manufacture of cell mass from organic matter.
- Household or domestic waste- Solid waste, composed of garbage and rubbish, which normally originates from residential, private households, or apartment buildings. Domestic waste may contain a significant amount of toxic or hazardous waste from improperly discarded pesticides, paints, batteries, and cleaners.
- Hydraulic conductivity- A coefficient of proportionality describing the rate at which water can move through a permeable medium. Hydraulic conductivity is a function of both the intrinsic permeability of the porous medium and the kinematic viscosity of the water which flows through it. Also referred to as the coefficient of permeability.
- Hydraulic gradient- The change in total potentiometric (or piezometric) head between two points divided by the horizontal distance separating the two points.
- Hydrocarbon(s)- Chemicals that consist entirely of hydrogen and carbon. Hydrocarbons contribute to air pollution problems like smog.
- Hydrogen peroxide- Hydrogen peroxide is used to increase the dissolved oxygen content of groundwater to stimulate aerobic biodegradation of organic contaminants. Hydrogen peroxide is infinitely soluble in water, but rapidly dissociates to form a molecule of water and one-half molecule of oxygen. Dissolved oxygen concentrations of greater than 1,000 mg/L are possible using hydrogen peroxide, but high levels of D.O. can be toxic to microorganisms.
- Hydrophilic- Having an affinity for water, or capable of dissolving in water; soluble or miscible in water.
- Hydrophobic- Tending not to combine with water, or incapable of dissolving in water; insoluble or immiscible in water. A property exhibited by non-polar organic compounds, including the petroleum hydrocarbons.
- Hypoxic- A condition of low oxygen concentration, below that considered aerobic.
- Identification code- The unique code assigned to each generator, transporter, and treatment, storage, or disposal facility by EPA to facilitate identification and tracking of hazardous waste. Superfund sites also have assigned I.D. numbers.
- In situ- In its original place; unmoved; unexcavated; remaining in the subsurface.
- Incineration- The destruction of solid, liquid, or gaseous wastes by controlled burning at high temperatures. Hazardous organic compounds are converted to ash, carbon dioxide, and water. Burning destroys organics, reduces the volume of waste, and vaporizes water and other liquids the wastes may contain. The residue ash produced may contain some hazardous material, such as non-combustible heavy metals, concentrated from the original waste.
- Indigenous- Living or occurring naturally in a specific area or environment; native.
- Indirect discharge- The introduction of pollutants from a non-domestic source into a publicly owned wastewater treatment system. Indirect dischargers can be commercial or industrial facilities who must pre-treat their wastes before discharge into local sewers.
- Indirect Effects- Indirect impacts are “caused by the action and are later in time or farther removed in distance, but are still reasonably foreseeable” (40 C.F.R. ¿ 1508.8).
- Indoor air- Breathing air inside a habitable structure, often highly polluted because of lack of exchange with fresh oxygen from outdoors. Solvents, smoke, paints, furniture glues, carpet padding, and other synthetic chemicals trapped inside contribute to an often unhealthy environment.
- Industrial waste- Unwanted materials produced in or eliminated from an industrial operation and categorized under a variety of headings, such as liquid wastes, sludge, solid wastes, and hazardous wastes.
- Inert ingredients- Substances that are not “active,” such as water, petroleum distillates, talc, corn meal, or soaps. When discussing pesticides, inert ingredients do not attack a particular pest, but some are chemically or biologically active, causing health and environmental problems.
- Infiltration- The downward movement of water through a soil in response to gravity and capillary suction.
- Infiltration gallery- An engineered structure that facilitates infiltration of water into the subsurface. Infiltration galleries may consist of one or more horizontal or vertical perforated pipes, a single gravel-filled trench or a network of such trenches, or a combination of these.
- Injection well- A well used to inject under pressure a fluid (liquid or gas) into the subsurface.
- Inlet well- A well through which a fluid (liquid or gas) is allowed to enter the subsurface under natural pressure.
- Innovative technology- New or inventive methods to treat hazardous wastes, conserve energy, or prevent pollution.
- Inoculate- To implant microorganisms onto or into a culture medium.
- Integrated pest management- A combination of biological, cultural, and genetic pest control methods with use of pesticides as the last resort. IPM development to reduce the population. Land use practices are examined for possible change; other animals, birds, or reptiles in the ecosystem are used as natural predators.
- Intergranular- Between the individual grains in a rock or sediment.
- Interstate commerce- A clause of the United States Constitution which reserves to the federal government the right to regulate the conduct of business across state lines. Under this clause, the U.S. Supreme Court has ruled that states may not restrict the disposal of wastes originating out-of-state more than that of waste originating in-state.
- Inversion- An atmospheric condition caused by increasing temperature with elevation, resulting in a layer of warm air preventing the rise of cooler air trapped beneath. This condition prevents the rise of pollutants that might otherwise be dispersed. Trapping pollutants near the ground increases ozone to harmful levels.
- Irradiated food- Food that has been briefly exposed to radioactivity (usually gamma rays) to kill insects, bacteria, and mold. Irradiated food can be stored without refrigeration or chemical preservatives and has a long “shelf life.”
- Isotropic- The condition in which hydraulic properties of an aquifer are equal when measured in any direction.
- Kinematic viscosity- The ratio of dynamic viscosity to mass density. Kinematic viscosity is a measure of a fluid’s resistance to gravity flow: the lower the kinematic viscosity, the easier and faster the fluid will flow.
- Lagoon- A shallow, artificial treatment pond where sunlight, bacterial action, and oxygen work to purify wastewater; a stabilization pond. An aerated lagoon is a treatment pond that uses oxygen to speed up the natural process of biological decomposition of organic wastes. A lagoon is regulated as a point source under the Clean Water Act if there is a direct surface water discharge. Some lagoons that discharge into ground water also are regulated if they have a direct hydrogeologic connection to surface water. In other areas, lagoons were historically used to dump various liquid, solid, and hazardous wastes from manufacturing or industrial processes. These wastes typically flooded and polluted surrounding environs or seeped underground. Such lagoons are now regulated under RCRA but some must be cleaned up under Superfund.
- Land disposal restrictions- Mandated by the 1984 amendments to RCRA; prohibits the disposal of hazardous wastes into or on the land.
- Landfill- A method for final disposal of solid waste on land. The refuse is spread and compacted and a cover of soil applied so that effects on the environment (including public health and safety) are minimized. Under current regulations, landfills are required to have liners and leachate treatment systems to prevent contamination of ground water and surface waters. An industrial landfill disposes of non-hazardous industrial wastes. A municipal landfill disposes of domestic waste including garbage, paper, etc. This waste may include toxins that are used in the home, such as insect sprays and powders, engine oil, paints, solvents, and weed killers.
- Large quantity generator- Person or facility which generates more than 2,200 pounds of hazardous waste per month. In 1989, only 1% of more than 20,000 generators fell into this category. Those generators produced nearly 97% of the nation’s hazardous waste. These generators are subject to all requirements of RCRA.
- Leachate- Liquid (mainly water) that percolates through a landfill and has picked up dissolved, suspended, and/or microbial contaminants from the waste. Leachate can be compared to coffee: water that has percolated down through the ground coffee.
- Lethal concentration 50- A concentration of a pollutant or effluent at which 50% of the test organisms die; a common measure of acute toxicity.
- Lethal dose 50- The dose of a toxicant that will kill 50% of test organisms within a designated period of time. The lower the LD 50, the more toxic the compound.
- Limited degradation- A policy that allows for some lowering of natural environmental quality to a given level beneath an established health standard.
- Liner- Structure of natural clay or manufactured material (plastic) which serves as a barrier to restrict leachate from reaching or mixing with ground water in landfills, lagoons, etc.
- Liquid limit (LL)- The lower limit for viscous flow of a soil.
- Liquidity index (LI)- Quantitative value used to assess whether a soil will behave as a brittle solid, semisolid, plastic, or liquid. LI is equal to the difference between the natural moisture content of the soil and the plastic limit (PL) divided by the plasticity index (PI).
- Lithology- The gross physical character of a rock or rock types in a stratigraphic section.
- Litter- The highly visible portion of solid waste (usually packaging material) which is generated by the consumer and carelessly discarded outside of the regular garbage disposal system, as on the highways or in streets.
- Local emergency planning committee- The body appointed by the State Emergency Response Commission (SERC), as required by EPCRA, which develops comprehensive emergency plans for Local Emergency Planning Districts, collects MSDS forms and chemical release reports, and provides this information to the public. Each county and some large city governments participate in an LEPC.
- Lower explosive limit (LEL)- The concentration of a gas below which the concentration of vapors is insufficient to support an explosion. LELs for most organics are generally 1 to 5 percent by volume.
- Manometer – An instrument for measuring fluid pressure. Typically a U-shaped tube in which opposing fluid pressures reach an equilibrium. The pressure is equal to the differences in the levels of the fluid on either side of the tube.
- Material Safety Data Sheet- Printed material concerning a hazardous chemical, or Extremely Hazardous Substance, including its physical properties, hazards to personnel, fire and explosion potential, safe handling recommendations, health effects, fire fighting techniques, reactivity, and proper disposal. Originally established for employee safety by OSHA.
- Maximum Achievable Control Technology- Generally, the best available control technology, taking into account cost and technical feasibility.
- Maximum Contaminant Level- The maximum level of certain contaminants permitted in drinking water supplied by a public water system as set by EPA under the federal Safe Drinking Water Act.
- Maximum Contaminant Level Goal- The maximum level of a contaminant that is associated with no adverse health effects from drinking water containing that contaminant over a lifetime. For chemicals believed to cause cancer, the MCLGs are set at zero. MCLGs are not enforceable, but are ideal, health-based goals which are set in the National Primary Drinking Water Standards developed by EPA. MCLs are set as close to MCLGs as possible, considering costs and technology.
- Medical waste- All wastes from hospitals, clinics, or other health care facilities (“Red Bag Waste”) that contain or have come into contact with diseased tissues or infectious microorganisms. Also referred to as infectious waste which is hazardous waste with infectious characteristics, including: contaminated animal waste, human blood and blood products, pathological waste, and discarded sharps (needles, scalpels, or broken medical instruments).
- Metabolism- A term that encompasses all of the diverse reactions by which a cell processes food material to obtain energy and the compounds from which new cell components are made.
- Methanogenic- Referring to the formation of methane by certain anaerobic bacteria during the process of anaerobic fermentation.
- Microaerophilic- Obligate aerobes that function best under conditions of low oxygen concentration.
- Microcosm- A diminutive, representative system analogous to a larger system in composition, development, or configuration. As used in biodegradation treatability studies, microcosms are typically constructed in glass bottles or jars.
- Microorganisms- Bacteria, yeasts, simple fungi, algae, protozoans, and a number of other organisms that are microscopic in size. Most are beneficial but some produce disease. Others are involved in composting and sewage treatment.
- Milligrams/liter- A measure of concentration used in the measurement of fluids. Mg/l is the most common way to present a concentration in water and is roughly equivalent to parts per million.
- Mineralization- The release of inorganic chemicals from organic matter in the process of aerobic or anaerobic decay.
- Minimization- Measures or techniques that reduce the amount of wastes generated during industrial production processes; this term also is applied to recycling and other efforts to reduce the volume of waste going to landfills. This term is interchangeable with waste reduction and waste minimization.
- Moisture content- The amount of water lost from a soil upon drying to a constant weight, expressed as the weight per unit weight of dry soil or as the volume of water per unit bulk volume of the soil. For a fully saturated medium, moisture content equals the porosity.
- Molecular diffusion- Process whereby molecules of various gases tend to intermingle and eventually become uniformly dispersed.
- Molecular weight- The amount of mass in one mole of molecules of a substance as determined by summing the masses of the individual atoms which make up the molecule.
- Mutagenicity- The property of a chemical that causes the genetic characteristics of an organism to change in such a way that future generations are permanently affected.
- National Ambient Air Quality Standards- Maximum air pollutant standards that EPA set under the Clean Air Act for attainment by each state. The standards were to be achieved by 1975, along with state implementation plans to control industrial sources in each state.
- National Pollutant Discharge Elimination System- The primary permitting program under the Clean Water Act which regulates all discharges to surface water.
- National Priorities List- A list of sites, many nominated by the states, for hazardous waste cleanup under Superfund.
- National Response Center- The primary communications center operated by the U.S. Coast Guard to receive reports of major chemical and oil spills and other hazardous substances into the environment. The NRC immediately relays reports to a predesignated federal On-Scene Coordinator.
- National Response Team- Representatives from 15 federal agencies with interests and expertise in various aspects of emergency response to pollution incidents. EPA serves as chair and the U.S. Coast Guard serves as vice-chair. The NRT is primarily a national planning, policy, and coordinating body and does not respond directly to incidents. The NRT provides policy guidance prior to an incident and assistance as requested by a federal On-Scene Coordinator via a Regional Response Team during an incident. NRT assistance usually takes the form of technical advice, access to additional resources or equipment, or coordination with other RRTs.
- National Strike Force- Operated by the U.S. Coast Guard, the NSF is composed of three strategically located teams (Atlantic, Pacific, and Gulf coasts) who back up the federal On-Scene Coordinator. These teams are extensively trained and equipped to respond to major oil spills and chemical releases. These capabilities are especially suited to incidents in a marine environment but also include site assessment, safety, action plan development, and documentation for both inland and coastal zone incidents. The NSF Coordination Center is at Elizabeth City, NC.
- Neutralization- The chemical process in which the acidic or basic characteristics of a fluid are changed to those of water (pH = 7).
- No Observed Adverse Effect Level- A level of exposure which does not cause observable harm.
- No Observed Effect Level- A level of exposure which does not cause observable harm.
- Non-aqueous phase liquid (NAPL)- Contaminants that remain as the original bulk liquid in the subsurface.
- Non-attainment- Refers to areas of the United States that have not met air standards for human health by deadlines set in the Clean Air Act.
- Nonpoint source- Any source of pollution not associated with a distinct discharge point. Includes sources such as rainwater, runoff from agricultural lands, industrial sites, parking lots, and timber operations, as well as escaping gases from pipes and fittings.
- Notice of Availability (NOA)- A notice placed in the newspaper and other appropriate communication channels that announces the availability of a Draft EIS or Final EIS for public review.
- Notice of Intent (NOI)- A notice placed in the Federal Register, notifying the public that a federal agency is considering taking a major federal action that may have a significant impact on the environment and for which an EIS will be prepared. The NOI describes the proposed action and possible alternatives and the proposed scoping process (including whether, when, and where scoping meetings will be held) and provides contact information. See 40 C.F.R. ¿ 1508.22.
- Nutrients- Major elements (e.g., nitrogen and phosphorus) and trace elements (including sulfur, potassium, calcium, and magnesium) that are essential for the growth of organisms.
- Obligate aerobes- Organisms that require the presence of molecular oxygen for their metabolism.
- Obligate anaerobes- Organisms for which the presence of molecular oxygen is toxic. These organisms derive the oxygen needed for cell synthesis from chemical compounds.
- Octanol/water partition coefficient (KOW)- A coefficient representing the ratio of the solubility of a compound in octanol (a non-polar solvent) to its solubility in water (a polar solvent). The higher the Kow, the more non-polar the compound. Log Kow is generally used as a relative indicator of the tendency of an organic compound to adsorb to soil. Log Kow values are generally inversely related to aqueous solubility and directly proportional to molecular weight.
- Odor threshold- The lowest concentration of a substance in air that can be smelled. Odor thresholds are highly variable because of the differing ability of individuals to detect odors.
- Off-gas treatment system- Refers to the unit operations used to treat (i.e. condense, collect, or destroy) contaminants in the purge gas from the thermal desorber.
- On site- On the same, or adjacent, property.
- On-Scene Coordinator- The federal official responsible for the coordination of a hazardous materials response action, as specified in individual Regional Contingency Plans. OSCs are predesignated by EPA for inland areas and by the U.S. Coast Guard for coastal areas. The OSC coordinates all federal containment, removal, and disposal efforts and resources during a pollution incident. The OSC is the point of contact for the coordination of federal efforts with those of the local response community. The OSC has access to extensive federal resources, including the National Strike Force, the Environmental Response Team, and Scientific Support Coordinators. The OSC can be a source of valuable support and information to the community.
- Organically grown- Food, feed crops, and livestock grown within an intentionally-diversified, self-sustaining agro-ecosystem. In practice, farmers build up nutrients in the soil using compost, agricultural wastes, and cover crops instead of synthetically derived fertilizers to increase productivity, rotate crops, weed mechanically, and reduce dramatically their dependence on the entire family of pesticides. Farmers must be certified to characterize crops as organically grown and can only use approved natural and synthetic biochemicals, agents, and materials for three consecutive years prior to harvest. Livestock must be fed a diet that includes grains and forages that have been organically grown and cannot receive hormones, sub-therapeutic antibiotics, or other growth promoters.
- Organism- Any living being, whether plant, mammal, bird, insect, reptile, fish, crustacean, aquatic or estuarine animal, or bacterium.
- Orifice plate- A flow measurement device for liquids or gases that uses a restrictive orifice plate consisting of a machined hole that produces a jet effect. Typically the orifice meter consists of a thin plate with a square edged, concentric, and circular orifice. The pressure drop of the jet effect across the orifice is proportional to the flow rate. The pressure drop can be measured with a manometer or differential pressure gauge.
- Oxidant – A substance containing oxygen that reacts chemically with other materials to produce new substances. Oxidants are the primary ingredients in smog.
- Oxidation-reduction (Redox)- A chemical reaction consisting of an oxidation reaction in which a substance loses or donates electrons, and a reduction reaction in which a substance gains or accepts electrons. Redox reactions are always coupled because free electrons cannot exist in solution and electrons must be conserved.
- Ozone- Three molecule oxygen compound found in two layers of the earth’s atmosphere. One layer of beneficial ozone occurs at seven to 18 miles above the surface and shields the earth from ultraviolet light. Several holes in this protective layer have been documented by scientists. Ozone also concentrates at the surface as a result of reactions between by-products of fossil fuel combustion and sunlight, having harmful health effects.
- Partial pressure- The portion of total vapor pressure in a system due to one or more constituents in the vapor mixture.
- Parts per billion- One ppb is comparable to one kernel of corn in a filled, 45-foot silo, 16 feet in diameter.
- Parts per million- One ppm is comparable to one drop of gasoline in a tankful of gas (full-size car).
- Parts per trillion- One ppt is comparable to one drop in a swimming pool covering the area of a football field 43 ft. deep.
- Pathogen- A bacterial organism typically found in the intestinal tracts of mammals, capable of producing disease.
- Permeability- A qualitative description of the relative ease with which rock, soil, or sediment will transmit a fluid (liquid or gas). Often used as a synonym for hydraulic conductivity or coefficient of permeability.
- Permissible Exposure Limit- Workplace exposure limits for contaminants established by OSHA.
- Permit- A legal document issued by state and/or federal authorities containing a detailed description of the proposed activity and operating procedures as well as appropriate requirements and regulations. The permitting process includes provisions for public comment.
- Pesticide- Substances intended to repel, kill, or control any species designated a “pest” including weeds, insects, rodents, fungi, bacteria, or other organisms. The family of pesticides includes herbicides, insecticides, rodenticides, fungicides, and bactericides.
- pH- A measure of the acidity of a solution. pH is equal to the negative logarithm of the concentration of hydrogen ions in a solution. A pH of 7 is neutral. Values less than 7 are acidic, and values greater than 7 are basic.
- Phototrophs- Organisms that use light to generate energy (by photosynthesis) for cellular activity, growth, and reproduction.
- Pilot test- Operation of a small-scale version of a larger system to gain information relating to the anticipated performance of the larger system. Pilot test results are typically used to design and optimize the larger system.
- Plastic limit (PL)- The lower limit of the plastic state of a soil.
- Plastic soil- One that will deform without shearing (typically silts or clays). Plasticity characteristics are measured using a set of parameters known as Atterberg Limits.
- Plasticity index (PI)- The range of water content in which soil is in a plastic state. PI is calculated as the difference between the percent liquid limit and percent plastic limit.
- Plume- A concentration of contaminants in air, soil, or water usually extending from a distinct source.
- Point source- A stationary location or fixed facility such as an industry or municipality that discharges pollutants into air or surface water through pipes, ditches, lagoons, wells, or stacks; a single identifiable source such as a ship or a mine.
- Pollution- Any substances in water, soil, or air that degrade the natural quality of the environment, offend the senses of sight, taste, or smell, or cause a health hazard. The usefulness of the natural resource is usually impaired by the presence of pollutants and contaminants.
- Pollution prevention- Actively identifying equipment, processes, and activities which generate excessive wastes or use toxic chemicals and then making substitutions, alterations, or product improvements. Conserving energy and minimizing wastes are pollution prevention concepts used in manufacturing, sustainable agriculture, recycling, and clean air/clean water technologies.
- Polychlorinated Biphenyls (PCBs)- A group of toxic, persistent chemicals used in electrical transformers and capacitors for insulating purposes, and in gas pipeline systems as a lubricant. The sale and new use of PCBs were banned by law in 1979.
- Pore volume- A process in which something is taken up and held; as used in the Superfund Program, sorption refers to technologies that use a sorption agent that attracts, takes up, and holds hazardous waste for removal.
- Porosity- The volume fraction of a rock or unconsolidated sediment not occupied by solid material but usually occupied by water and/or air.
- Potable water- Raw or treated water that is considered safe to drink.
- Pounds per square inch (PSI)- A unit of pressure or pressure drop across a flow resistance. One psi is equivalent to the pressure exerted by 2.31 feet of water column.
- Pressure gradient- A pressure differential in a given medium(e.g., water or air) which tends to induce movement from areas of higher pressure to areas of lower pressure.
- Pretreatment- Methods used by industry and other non-household sources of wastewater to remove, reduce, or alter the pollutants in wastewater before discharge to a POTW.
- Primary treatment- First stage of wastewater treatment in which solids are removed by screening and settling.
- Public comment period- The time allowed for the members of an affected community to express views and concerns regarding an action proposed to be taken by EPA, such as a rulemaking, permit, or Superfund remedy selection.
- Public water system- Any water system that regularly supplies piped water to the public for consumption, serving at least an average of 25 individuals per day for at least 60 days per year, or has at least 15 service connections.
- Publicly Owned Treatment Works- A municipal or public service district sewage treatment system.
- Pugmill- A chamber in which water and soil are mixed together. Typically mixing is aided by an internal mechanical stirring/kneading device.
- Quality assurance/quality control- A system of procedures, checks, audits, and corrective actions to ensure that all technical, operational, monitoring, and reporting activities are of the highest achievable quality.
- Radioactive waste- Any waste that emits energy as rays, waves, or streams of energetic particles. Radioactive materials are often mixed with hazardous waste, usually from nuclear reactors, research institutions, or hospitals.
- Radius of influence- The maximum distance away from an air injection or extraction source that is significantly affected by a change in pressure and induced movement of air.
- Radon- A colorless, naturally occurring gas formed by radioactive decay of radium atoms. Radon accumulating in basements and other areas of buildings without proper ventilation has been identified as a leading cause of lung cancer.
- Reactivity- Refers to those hazardous wastes that are normally unstable and readily undergo violent chemical change but do not explode.
- Reagent- A substance or solution used in a chemical reaction, especially those used in laboratory work to detect, measure, or produce other substances.
- Recharge area- An area of land where there is a net annual transfer of water from the surface to ground water; where rainwater soaks through the earth to reach an aquifer.
- Record of Decision- A public document that explains which cleanup alternative was selected for a Superfund site.
- Record of Decision (ROD)- A public document stating the final decision on a proposed action for which a Final Environmental Impact Statement (EIS) has been prepared. The ROD includes a brief description of the proposed action and alternatives considered in the EIS, environmental factors considered, and project impacts; any commitments to mitigation; an explanation if an environmental preferred alternative was not selected; and responses to any substantive comments on the Final EIS.
- Recycling- Reusing materials and objects in original or changed forms rather than discarding them as wastes.
- Refine- To remove impurities.
- Refractory index- A measure of the ability of a substance to be biodegraded by bacterial activity. The lower the refractory index, the greater the biodegradability.
- Regional response team- There are 13 RRTs, one for each of 10 federal regions, plus one for Alaska, one for the Caribbean, and one for the Pacific Basin. Each RRT maintains a Regional Contingency Plan and has state and federal government representation. EPA and the U.S. Coast Guard cochair the RRTs. Like the NRT, RRTs are planning, policy, and coordinating bodies and do not respond directly to pollution incidents but do provide assistance when requested by the federal On-Scene Coordinator. RRTs also provide assistance to SERCs and LEPCs in local preparedness, planning, and training for emergency response.
- Remedial action- The actual construction or clean-up phase of a Superfund site cleanup.
- Reportable quantity- Amount of a hazardous or extremely hazardous substance that, if released into the environment, must be reported to the NRC, the SERC, and the LEPC under Section 304 of EPCRA.
- Residual risk- The risk associated with pollutants after the application of maximum achievable control technology or MACT.
- Resource recovery- The extraction of useful materials or energy from solid waste. Such materials can include paper, glass, and metals that can be reprocessed for re-use. Resource recovery also is employed in pollution prevention.
- Responsiveness summary- A summary of oral and written comments received by EPA during a public comment period on key documents or actions proposed to be taken, and EPA’s response to those comments.
- Retardation- Preferential retention of contaminant movement in the subsurface resulting from adsorptive processes or solubility differences.
- Risk assessment- A process to determine the increased risk from exposure to environmental pollutants together with an estimate of the severity of impact. Risk assessments use specific chemical information plus risk factors.
- Risk communication- The process of exchanging information about levels or significance of health or environmental risk.
- Risk factor- A characteristic (e.g., race, sex, age, obesity) or variable (e.g., smoking, exposure) associated with increased chance of toxic effects. Some standard risk factors used in general risk assessment calculations include average breathing rates, average weight, and average human life span.
- Sanitary water- Water discharged from restrooms, showers, food preparation facilities, or other nonindustrial operations; also known as “gray water.”
- Saturated zone- The zone in which all the voids in the rock or soil are filled with water at greater than atmospheric pressure. The water table is the top of the saturated zone in an unconfined aquifer.
- Scientific Support Coordinators- Scientific and technical advisors in coastal and marine areas from the National Oceanic and Atmospheric Administration (NOAA) who serve as members of the federal On-Scene Coordinator’s staff. Their capabilities include contingency planning, surface/subsurface trajectory forecasting and hindcasting, resource risk analysis, and liaison to other scientists.
- Scrubbing- A common method of reducing stack air emissions; removal of impurities by spraying a liquid that concentrates the impurities into waste.
- Secondary treatment- The second step taken by a Publicly Owned Treatment Works in which bacteria consume the organic parts of the waste. This treatment usually removes about 90% of all solids and oxygen-demanding substances.
- Sediment- Topsoil, sand, and minerals washed from the land into water, usually after rain or snow melt. Sediments collecting in rivers, reservoirs, and harbors can destroy fish and wildlife habitat and cloud the water so that sunlight cannot reach aquatic plants. Loss of topsoil from farming, mining, or building activities can be prevented through a variety of erosion-control techniques.
- Sentinel well- A groundwater monitoring well situated between a sensitive receptor downgradient and the source of a contaminant plume upgradient. Contamination should be first detected in the sentinel well which serves as a warning that contamination may be moving closer to the receptor. The sentinel well should be located far enough upgradient of the receptor to allow enough time before the contamination arrives at the receptor to initiate other measures to prevent contamination from reaching the receptor, or in the case of a supply well, provide for an alternative water source.
- Septic tank- An underground tank to collect wastes from homes that are not connected to a municipal sewer system. Waste goes from the home to the tank and is decomposed by bacteria. Solids and dead bacteria settle to the bottom as sludge while the liquid portion flows into the ground through drains. While properly placed and maintained septic systems can effectively treat domestic wastewater, others are a major source of ground water and surface water pollution.
- Sequestration- The inhibition or stoppage of normal ion behavior by combination with added materials, especially the prevention of metallic ion precipitation from solution by formation of a coordination complex with a phosphate.
- SESOIL- A one-dimensional model for estimating pollutant distribution in an unsaturated soil column. SESOIL results are commonly used to estimate the source term for groundwater transport modeling of the saturated zone.
- Short circuiting- The entry of ambient air into an extraction well (used for SVE and bioventing) without first passing through the contaminated zone. Short circuiting may occur through utility trenches, incoherent well or surface seals, or layers of high permeability geologic materials.
- Sludge- The residue (solids and some water) produced as a result of raw or wastewater treatment.
- – A pumpable mixture of solids and fluid.
- Smog- Dust, smoke, or chemical fumes that pollute the air and make hazy, unhealthy conditions (literally, the word is a blend of smoke and fog). Automobile, truck, bus, and other vehicle exhausts and particulates are usually trapped close to the ground, obscuring visibility and contributing to a number of respiratory problems.
- Soil moisture – The water contained in the pore spaces in the unsaturated zone.
- Solid waste- As defined under RCRA, any solid, semi-solid, liquid, or contained gaseous materials discarded from industrial, commercial, mining, or agricultural operations, and from community activities. Solid waste includes garbage, construction debris, commercial refuse, sludge from water supply or waste treatment plants, or air pollution control facilities, and other discarded materials.
- Solid Waste Management Facility- Any disposal or resource recovery system; any system, program, or facility for resource conservation; any facility for the treatment of solid wastes.
- Solubility- The amount of mass of a compound that will dissolve in a unit volume of solution.
- Sorption- A general term used to encompass the processes of absorption, adsorption, ion exchange, and chemisorption.
- Source reduction- The design, manufacture, purchase, or use of materials (such as products and packaging) to reduce the amount or toxicity of garbage generated. Source reduction can help reduce waste disposal and handling charges because the costs of recycling, municipal composting, landfilling, and combustion are avoided. Source reduction conserves resources and reduces pollution.
- Source separation- Organizing materials by type (such as paper, metal, plastic, and glass) so that these items can be recycled instead of thrown away. For example, many of us separate these items from the rest of our household and office wastes. Industries also organize materials in this fashion.
- Sparge- Injection of air below the water table to strip dissolved volatile organic compounds and/or oxygenate the groundwater to facilitate aerobic biodegradation of organic compounds.
- Specific gravity- The dimensionless ratio of the density of a substance with respect to the density of water. The specific gravity of water is equal to 1.0 by definition. Most petroleum products have a specific gravity less than 1.0, generally between 0.6 and 0.9. As such, they will float on water–these are also referred to as LNAPLs, or light non-aqueous phase liquids. Substances with a specific gravity greater than 1.0 will sink through water–these are referred to as DNAPLs, or dense non-aqueous phase liquids.
- Standard Industrial Classification Code- A method of grouping industries with similar products or services and assigning codes to these groups.
- State Emergency Response Commission- The agency appointed by the Governor to oversee the administration of EPCRA at the state level. This commission designates and appoints members to LEPCs and reviews emergency response plans for cities and counties.
- Stratification- Layering or bedding of geologic materials (e.g., rock or sediments).
- Stratum- A horizontal layer of geologic material of similar composition, especially one of several parallel layers arranged one on top of another.
- Sump- A pit or depression where liquids drain, collect, or are stored.
- Surface water- All water naturally open to the atmosphere (rivers, lakes, reservoirs, ponds, streams, seas, estuaries) and all springs, wells, or other collectors directly influenced by surface water.
- Sustainable agriculture- Environmentally friendly methods of farming that allow the production of crops or livestock without damage to the farm as an ecosystem, including effects on soil, water supplies, biodiversity, or other surrounding natural resources. The concept of sustainable agriculture is an “intergenerational” one in which we pass on a conserved or improved natural resource base instead of one which has been depleted or polluted. Terms often associated with farms or ranches that are self-sustaining include “low-input,” organic, “ecological,” “biodynamic,” and “permaculture.”
- Synergism- The cooperative action of two or more organisms producing a greater total result than the sum of their independent effects; chemicals or muscles in synergy enhance the effectiveness of one another beyond what an individual could have produced.
- Tedlar bags- Gas-tight bags constructed of non-reactive material (Tedlar) for the collection and transport of gas/vapor samples.
- Ten-to-the-minus-sixth- Used in risk assessments to refer to the probability of risk. Literally means a chance of one in a million. Similarly, ten-to-the-minus-fifth means a probability of one in 100,000, and so on.
- Teratogen- A substance capable of causing birth defects.
- Tertiary treatment- An enhancement of normal sewage treatment operations to provide water of potable quality using further chemical and physical treatment; the highest drinking water standard achieved in the U.S.
- Thermal desorber- Describes the primary treatment unit that heats petroleum-contaminated materials and desorbs the organic materials into a purge gas or off-gas.
- Thermal desorption system- Refers to a thermal desorber and associated systems for handling materials and treated soils and treating offgases and residuals.
- Threshold limit value- The concentration of an airborne substance that a healthy person can be exposed to for a 40-hour work week without adverse effect; a workplace exposure standard.
- Total dissolved solids- The quantity of dissolved material in a given volume of water.
- Toxic chemical- Substances that can cause severe illness, poisoning, birth defects, disease, or death when ingested, inhaled, or absorbed by living organisms.
- Toxic cloud- An airborne mass of gases, vapors, fumes, or aerosols of toxic materials.
- Toxic Release Inventory- A database of annual toxic releases from certain manufacturers compiled from EPCRA Section 313 reports. Manufacturers must report annually to EPA and the states the amounts of almost 350 toxic chemicals and 22 chemical categories that they release directly to air, water, or land, inject underground, or transfer to off-site facilities. EPA compiles these reports and makes the information available to the public under the “Community Right-to-Know” portion of the law.
- Toxic substance- A chemical or mixture that can cause illness, death, disease, or birth defects. The quantities and exposures necessary to cause these effects can vary widely. Many toxic substances are pollutants and contaminants in the environment.
- Toxicity Characteristic Leaching Procedure- A test designed to determine whether a waste is hazardous or requires treatment to become less hazardous; also can be used to monitor treatment techniques for effectiveness.
- Trade secret- Any confidential formula, pattern, process, device, information, or set of data that is used in a business to give the owner a competitive advantage. Such information may be excluded from public review.
- Travel time- The time it takes a contaminant to travel from the source to a particular point downgradient.
- Treatment, Storage, and Disposal Facility- Refers to any facility which treats, stores, or disposes of hazardous wastes.
- Ultraviolet rays- Radiation from the sun in the invisible portion of the spectrum. Some UV rays (UV-A) enhance plant life and are useful in certain medical and dental procedures. Other UV rays (UV-B) can cause skin cancer or other tissue damage. The ozone layer in the atmosphere partly shields us from ultraviolet rays reaching the earth’s surface.
- Unconfined aquifer- An aquifer in which there are no confining beds between the capillary fringe and land surface, and where the top of the saturated zone (the water table) is at atmospheric pressure.
- Underground storage tank- A tank and any underground piping connected to the tank that has 10% or more of its volume (including pipe volume) beneath the surface of the ground. USTs are designed to hold gasoline, other petroleum products, and hazardous materials.
- Unsaturated zone- The zone between land surface and the capillary fringe within which the moisture content is less than saturation and pressure is less than atmospheric. Soil pore spaces also typically contain air or other gases. The capillary fringe is not included in the unsaturated zone.
- Vacuum draft tube- A narrow tube lowered into an extraction well through which a strong vacuum is pulled via a suction pump at ground surface. Fluids (gas, water, and/or free product) are drawn into the draft tube and conveyed to the surface for treatment or disposal. Depending upon the configuration of the extraction system, the inlet of the draft tube may be either above or below the static level of the liquid in the well.
- Vadose zone- The zone between land surface and the water table within which the moisture content is less than saturation (except in the capillary fringe) and pressure is less than atmospheric. Soil pore spaces also typically contain air or other gases. The capillary fringe is included in the vadose zone.
- Vapor- The gas given off by substances that are solids or liquids at ordinary atmospheric pressure and temperatures.
- Vapor pressure- The force per unit area exerted by a vapor in an equilibrium state with its pure solid, liquid, or solution at a given temperature. Vapor pressure is a measure of a substance’s propensity to evaporate. Vapor pressure increases exponentially with an increase in temperature.
- Vapor recovery system- A system by which the volatile gases from gasoline are captured instead of being released into the atmosphere. Recovery systems may be required for gasoline stations in some cities and other non-attainment areas.
- Vent- The connection and piping through which gases enter and exit a piece of equipment.
- Viscosity- A measure of the internal friction of a fluid that provides resistance to shear within the fluid. The greater the forces of internal friction (i.e. the greater the viscosity), the less easily the fluid will flow.
- Volatile organic compounds (VOC)- Any organic compound which evaporates readily to the atmosphere. VOCs contribute significantly to photochemical smog production and certain health problems.
- Volatilization- The process of transfer of a chemical from the aqueous or liquid phase to the gas phase. Solubility, molecular weight, and vapor pressure of the liquid and the nature of the gas-liquid interface affect the rate of volatilization.
- Wastewater treatment plant- A facility containing a series of tanks, screens, filters, and other processes by which pollutants are removed from water. Most treatments include chlorination to attain safe drinking water standards.
- Water quality standard- The combination of a designated use and the maximum concentration of a pollutant which will protect that use for any given body of water. For example, in a trout stream, the concentration of iron should not exceed 1 mg/l.
- Water table- The boundary between the saturated and unsaturated zones. Generally, the level to which water will rise in a well (except artesian wells).
- Weathering- The process during which a complex compound is reduced to its simpler component parts, transported via physical processes, or biodegraded over time.
- Wellhead protection area- A protected surface and subsurface zone surrounding a well or well field that supplies a public water system and through which contaminants could likely reach well water.
- Wetlands- Areas that are soaked or flooded by surface or ground water frequently enough or for sufficient duration to support plants, birds, animals, and aquatic life. Wetlands generally include swamps, marshes, bogs, estuaries, and other inland and coastal areas, and are federally protected. Wetlands frequently serve as recharge/discharge areas and are known as “nature’s kidneys” since they help purify water. Wetlands also have been referred to as natural sponges that absorb flood waters, functioning like natural tubs to collect overflow. Wetlands are important wildlife habitats, breeding grounds, and nurseries because of their biodiversity. Many endangered species as well as countless estuarine and marine fish and shellfish, mammals, waterfowl, and other migratory birds use wetland habitat for growth, reproduction, food, and shelter. Wetlands are among the most fertile, natural ecosystems in the world since they produce great volumes of food (plant material).
- Xenobiotic- A term for non-natural or man-made substances found in the environment (i.e., synthetics, plastics).
- Z-list- OSHA’s Toxic and Hazardous Substances Tables (Z-1, Z-2, and Z-3) of air contaminants; any material found on these tables is considered hazardous.
- Zone of saturation- The layer beneath the surface of the land in which all openings are filled with water.
Glossary of Terms – From the New York State Department of Environmental Conservation (NYSDEC)
- Acid- Chemicals that have a high concentration of hydrogen ions. Acids have a pH of less than 7 on a scale of 0 to 14. Strong acids, closer to 0 on the scale are corrosive, and weak acids, with a pH closer to 7, are not. An acid is the opposite of a base.
- Activated carbon- A highly absorbent form of carbon, formed primarily from coal and lignite, that absorbs organic compounds. “Activated carbon treatment systems” are used to remove odors and toxic substances from liquid or gaseous emissions.
- Acute effects- Health effects that have a rapid onset, a short course, and pronounced symptoms and termination. A reaction that occurs shortly after exposure to a chemical.
- Acute exposure- A single, short contact with a chemical. It may last a few seconds or a few hours, but no longer than a day.
- Administrative order on consent- See Consent order Administrative record Part of a site’s Record of Decision (ROD) which lists and defines documents used in the development of DEC’s decision about selection of a remedial action.
- Adsorb/ Adsorption- Molecules of gas, liquid, or dissolved solids that adhere or “stick” to the surfaces they come in contact with. Some chemicals adsorb strongly to soil particles. This differs from absorb: “to take up or make part of the existing whole,” like a sponge absorbs (sucks up) water.
- Air sparging- Injecting air or oxygen into an aquifer to strip or flush volatile contaminants as air bubbles up through the ground water. The air is captured by a vapor extraction system. (See soil vapor extraction system).
- Air stripping- A treatment system that removes or “strips” volatile organic compounds from contaminated groundwater or surface water by forcing an airstream through the water and causing the compounds to evaporate.
- Ambient- The surrounding environment. Ambient usually refers to the surrounding outdoor air, water, or land.
- Anaerobic- Absence of oxygen. Some organisms, such as certain soil bacteria, thrive under anaerobic conditions in soil.
- Analyte- A chemical being tested for in a laboratory test.
- Arsenic- An element used in wood preservatives and pesticides.
- 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.
- Aquifer- An underground water-bearing formation of soil or rock commonly used for drinking water.
- Aquifer recharge- See Recharge Aquitard Geological formation that may contain groundwater but significant quantities of water will not move through it under normal conditions. May function as a confining layer.
- Attenuation- See Natural attenuation Availability session A scheduled gathering of program staff and members of the public in a casual setting, with or without a formal presentation or agenda but usually focusing on a specific aspect of a site’s remedial process.
- Background, Background level- The concentration of a substance in air, water, or soil that occurs naturally or is the result of human activities not related to a hazardous waste site; conditions in the area near, but not affected by, a hazardous waste site. “Background samples” are often taken to compare an area’s natural or pre-existing conditions to conditions at a hazardous waste site.
- Barrier protection layer- A layer of soil covering a geomembrane designed to protect the geomembrane from wear and tear caused by the weather, animals, etc.
- Base- Bases are chemicals that have a large concentration of hydroxyl (one hydrogen plus one oxygen atom) ions. A basic compound has a pH of more than 7 on a scale of 0 to 14. Strong bases, pH closer to 14, are corrosive. Weak bases, with pH closer to 7, are not. An acid can neutralize the effects of a base.
- Bedrock- The continuous solid rock of the continental crust. Bedrock can be found anywhere from the surface to hundreds of feet below ground. Bedrock can be solid or it can contain numerous cracks (fractures). Groundwater and chemicals can move through fractured bedrock.
- Benthic- bottom-dwelling; usually refers to aquatic life living at the bottom of a river, stream or lake.
- Bentonite- A very fine clay, expansible when moist, commonly used to provide a tight seal around a monitoring well. Also used in slurry walls.
- Bioaccumulation- The build-up of toxic materials in body tissues of fish and animals.
- Bioavailability- The extent to which a substance can readily be absorbed by an organism or is ready to interact in an organism’s metabolism.
- Bioremediation- The degradation (breakdown) or stabilization of contaminants in the environment by microorganisms. There are many remedial techniques that use microorganisms, such as bacteria, to break down contaminants. Any of these techniques may be called bioremediation.
- Biota- All the living organisms in a given area.
- Borehole- Hole made with drilling equipment.
- Boring- See Soil boring
- Brownfield- Abandoned, idled, or under-used properties where expansion or redevelopment is complicated by real or perceived environmental contamination. Brownfield sites can pose environmental, legal, and financial burdens on a community and its taxpayers. New York State provides funds through the 1996 Clean Water/Clean Air Bond Act to help municipalities that own brownfields but are not responsible for the contamination to investigate and clean up these sites. Brownfields cleaned up using Bond Act funds are also called Environmental Restoration Projects. The U.S. Environmental Protection Agency has a similar brownfield initiative.
- Cap See Landfill cap/ Landfill cover system
- Carbon adsorption- A process by which contaminants are removed from groundwater or surface water when the water is forced through tanks containing activated carbon, a material that attracts the contaminants.
- Carbon tetrachloride- A colorless, nonflammable liquid with a characteristic odor used as a solvent and in the synthesis of fluorocarbons.
- Carcinogen A cancer-producing substance.
- Catch basin or catch-basin 1) A structure used to catch sediments for contaminant retention, often on a stream. 2) A cistern or vault at the point where a pipe from inside a factory or a street gutter discharges into a sewer, to catch bulky matters which would not pass readily through the sewer.
- Carcinogenic- Capable of producing or inciting cancer.
- CERCLA See Comprehensive Environmental Response, Compensation, and Liability Act Chlorinated hydrocarbons Chemicals containing only chlorine, carbon, and hydrogen. These include some pesticides, such as DDT and heptachlor, and solvents such as trichloroethene and chloroform.
- Chlorinated organics- See Chlorinated Solvents Chlorinated solvents- A group of organic (carbon-containing) solvents which contain chlorine as a part of their molecular structure. Chlorinated solvents are widely used for metal parts cleaning, dry cleaning, chemical processing, and photographic film making. Common chlorinated solvents include chloroform, methylene chloride, carbon tetrachloride, trichloroethene, tetrachloroethene, and 1,1,1-trichloroethane.
- Chloroform A clear, colorless liquid with a characteristic odor. Chloroform was one of the earliest general anesthetics but this use was abandoned due to toxic effects. Now it is widely used as a solvent in the production of lacquer, pharmaceuticals, fluorocarbons, and plastics.
- Chronic effects A long-term or repeated reaction that occurs after an exposure to a chemical. Chronic effects are the opposite of acute effects.
- Citizen participation (CP) A process to inform and involve citizens in the decision-making process during identification, assessment and remediation of inactive hazardous waste sites. This process helps to assure that sound decisions are made from environmental, human health, economic, social and political perspectives.
- Citizen participation plan A document that describes the site-specific citizen participation activities that will take place to complement the investigation and clean-up activities at a hazardous waste site. A plan may be updated or altered as public interest or the technical aspects of the program change.
- Citizen participation record- A series of documents prepared at a major remedial stage which describes the citizen participation activities required at that stage. A CP record also directs a scoping process to determine if additional citizen participation activities are appropriate and feasible.
- Citizen participation specialist A DEC staff member within the Division of Public Affairs and Education who provides guidance, evaluation and assistance to help the project manager carry out the site-specific citizen participation program.
- Classification- See Site classification 1996 Clean Water/Clean Air Bond Act- Provides $1.75 billion for priority environmental programs to ensure further protection of New York’s air, water and natural resources, $200 million of which funds the Environmental Restoration Program, also known as the Brownfield Program, to provide financial assistance to municipalities for the investigation and /or cleanup of municipally-owned potentially contaminated properties. The municipality may then return these properties to productive use or can market them for redevelopment.
- Cleanup Action taken to respond to a hazardous material release or threat of a release that could affect humans and/or the environment. Also called remedial action, removal action, response action, or corrective action.
- Combustion Burning.
- Comment period- A time period for the public to review and comment on various documents and Division of Environmental Remediation (DER) actions. For example, a 30 day comment period is provided when DER issues a Proposed Remedial Action Plan (PRAP).
- Community relations- The Environmental Protection Agency’s program to inform and involve the public in the Superfund process and respond to community concerns.
- Community relations plan (CRP)- The formal plan for Environmental Protection Agency community relations activities at a Superfund site. The CRP is designed to ensure citizen opportunities for public involvement and allow citizens the opportunity to learn about a site.
- Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA)- A Federal law passed in 1980 and modified in 1986 by the Superfund Amendments and Reauthorization Act. CERCLA created a special tax that goes into a trust fund, commonly known as Superfund, to investigate and clean up abandoned or uncontrolled hazardous waste sites. Under the pro-gram, EPA can either pay for site cleanup when parties responsible for the contamination cannot be located or are unwilling or unable to perform the work; or take legal action to force parties responsible for site contamination to clean up the site or reimburse the government for the cost of cleanup.
- Cone of depression/ Cone of influence A depression in the water table that develops around a pumped well.
- Concentration- The amount of one substance in another substance. For example, a concentration of 10 milligrams per liter means there are 10 milligrams of a substance in 1 liter of another substance.
- Conceptual design The general outline of planned actions that will be taken to address a hazardous waste site, such as building a landfill cover system. The conceptual design is incorporated into detailed design documents during Remedial Design.
- Confining layer (confining bed)- A layer or bed of impermeable or distinctly less permeable material lying below or above one or more aquifers. When the confining layer lies between two aquifers, it keeps water from the upper aquifer separated, or confined, from water in the lower aquifer.
- Consent order A legal and enforceable negotiated agreement between DEC and responsible parties where responsible parties agree to undertake investigation and cleanup or pay for the costs of investigation and cleanup work at a site. Also called an “Order on Consent.”
- Construction and demolition (C&D) debris/ waste Waste building materials, dredging materials, tree stumps, and rubble resulting from construction, remodeling, repair, and demolition of homes, commercial buildings and other structures and pavements.
- Contact list- Names, addresses and/or telephone numbers of individuals, groups, organizations and media interested and/or affected by a particular hazardous waste site. The DEC mails site-related information to the contact list, also called a mailing list.
- Contaminant- Any physical, chemical, biological, or radiological substance or matter that has an adverse effect on air, water, or soil.
- Contamination Microorganisms, chemicals, toxic substances, wastes, or wastewater introduced into water, air, or soil in a concentration that makes the medium unfit for its next intended use. Objects such as building surfaces can also contain contamination.
- Contaminant mass The volume and area of contaminants in a polluted material, such as soil or groundwater. The goal of waste cleanup is to reduce the contaminant mass (e.g., reduce the amount and area of contaminants in soil).
- Contaminant plume See Plume Contract Laboratory Program (CLP)- The Environmental Protection Agency’s program that approves laboratories that provide chemical testing services of known quality using a wide range of standard methods and maintaining consistent quality control.
- Corrosive Having the power to degrade or wear away a material by chemical action.
- Cost recovery- A legal process where potentially responsible parties can be required to pay back the federal or state government for money spent on cleanup actions. Cost recovery actions usually begin after the government has completed a site cleanup.
- Cover material- (1) Soil used to cover compacted solid waste in a sanitary landfill. (2) See Landfill cap/landfill cover system.
- Cover system See Landfill cap/landfill cover system
- Deed notification- A notice placed on a property deed to alert future buyers about contamination on a property.
- Deed restriction- A legal restriction placed on a property deed to restrict future uses of a contaminated property. For example, a deed restriction may prohibit future housing development on a contaminated industrial site, or prohibit use of contaminated groundwater on a piece of property.
- Degradation products (Daughter products)- Chlorinated solvents, when released in the environment, will naturally degrade by microbial and physical processes in soil and/or groundwater into similar compounds that have fewer chlorine atoms. These new compounds are known as degradation products. For instance, tetrachloroethylene, which has 4 chlorine atoms, degrades to trichloroethylene, which has only 3 chloride atoms.
- Degreaser Chemical used to remove grease, usually from metal or plastic.
Delist/delisted/delisting- Many sites that have been cleaned up are delisted, meaning they are removed from the State’s Registry of Inactive Hazardous Waste Disposal Sites. Sites that are delisted can fall into one of three categories:
- D1: No consequential amount of hazardous waste was confirmed at the site.
- D1: No consequential amount of hazardous waste was confirmed at the site. D2: Remedial actions have been completed at the site and no further action is required.
- D1: No consequential amount of hazardous waste was confirmed at the site. D3: Site was combined with another site on the Registry of Inactive Hazardous Waste Disposal Sites.
- Dense Non-Aqueous Phase Liquid(DNAPL)- Liquids denser than water that represent a special class of soil and groundwater contaminants with unique behavior and problems. Since they are denser than water, DNAPLs can sink deeper into the ground and can act as a continuing source of groundwater contamination, as small amounts of the material can dissolve in groundwater.
- Density- The mass of a substance per unit of volume. Substances with a density greater than 1.0 are denser than water; substances with a density less than 1.0 are lighter than water.
- Dermal- By or through the skin. “Dermal contact” refers to a substance coming in contact with skin.
- Desorption- The opposite of adsorption or absorption; molecules detach from a surface (such as soil particles).
- Detection limit- The lowest concentration of a chemical that can be reliably measured by a testing method.
- Dewater- (1) Remove a portion of the water in soil or sludge to dry the soil/ sludge so it can be treated or disposed of. (2) Remove or drain the water from a tank or trench.
- 1,1-Dichloroethane (1,1-DCA) and 1,2-Dichloroethane (1,2-DCA)- Chemicals with similar molecular structures used to produce a variety of consumer and industrial products, such as specialty chemicals and cleaning products. These chemicals are sometime found at hazardous waste sites as the degradation products of other chemicals, such as trichloroethane.
- Dichloroethene (DCE) or 1,1-Dichloroethene and 1,2-Dichloroethene- Chemicals with similar molecular structures used to make specialty chemicals and pharmaceuticals. These chemicals are sometimes found at hazardous waste sites as the degradation products of trichloroethene.
- Diffusion- Movement of a substance from an area of high concentration to an area of low concentration. Diffusion can also refer molecules of gas or vapor moving from a source, such as a bottle, to a receptor, such as a human nose.
- Division of Environmental Enforcement- A unit within the DEC which works with the Division of Environmental Remediation to negotiate agreements with responsible parties for the investigation and remediation of hazardous waste sites. A negotiated agreement is contained in a consent order.
- Division of Environmental Remediation Formerly the Division of Hazardous Waste Remediation, a major unit within the DEC created to manage the hazardous waste site remedial program from site discovery through Operation and Maintenance activities. Staff include: engineers, geologists, chemists, attorneys, citizen participation specialists, environmental program specialists and support staff.
- Document Repository Typically, a DEC regional office and/or a public building, such as a library, near a particular site, at which documents related to remedial and citizen participation activities at the site are available for public review. Environ-mental Management Councils (EMCs), Conservation Advisory Committees (CACs) and active local groups can also serve as document repositories.
- Downgradient- The direction that groundwater flows; similar to “downstream” for surface water.
- Drainage Swale- See Swale Drawdown The vertical drop in the height between the water level in a well prior to pumping, and the water level in the well during pumping.
- Drum- A metal or plastic container, usually with a 55 gallon capacity.
- Drywell- A hole dug to a depth above the water table so that its bottom and sides are typically dry except when receiving fluid discharged from an industrial process. Is often filled with gravel or is reinforced with concrete blocks to form a chamber.
- Dual-Phase Vacuum Extraction System- A treatment system designed to remove both contaminated groundwater and soil gas from a common groundwater well or wells. By removing ground-water, the system lowers the groundwater level around the well, allowing a strong vacuum to be applied to remove contaminated soil gas. The contaminated water and air can then be removed or treated and released.
- Duplicate Sample A sample taken at the same location as another sample. Both samples are tested for chemicals. Taking a duplicate sample helps to ensure that testing procedures are precise: because the samples were taken in the same location, the samples should contain similar levels of chemicals.
- Effluent Treated or untreated wastewater that flows out of a treatment plant, sewer, or industrial outfall. Generally refers to wastes discharged to surface waters.
- Enforcement DEC’s efforts, through legal action if necessary, to compel a responsible party to perform or pay for site remedial activities.
- Engineered/engineering controls Method of managing environmental and health risks by placing a barrier between the contamination and the rest of the site, thus limiting exposure pathways.
- Environmental Notice Bulletin A weekly DEC publication used to announce a variety of DEC activities. The ENB announces proposals to delist or change the site classification of hazardous waste sites, as well as voluntary cleanup agreements.
- Environmental Restoration Program/ Project See Brownfield 1986 Environmental Quality
- Bond Act An act passed in 1986 that gives New York State bonding authority of up to $1.2 billion to fund the State’s share of the total cost of remediating hazardous waste sites in New York State.
- Epidemiology The study of diseases as they affect population, including the distribution of disease, the factors (e.g., age, sex, occupation) that influences this distribution; and the application of this study to control health problems.
- EP Tox Test See Extraction Procedure Explanation of Significant Differences (ESD) A document prepared by the Division of Environmental Remediation explaining changes to a cleanup plan called for in a Record of Decision and the reason for those changes.
- Explosive limits The amounts of vapor in air which form explosive mixtures. Explosive limits are expressed as “lower explosive limits” and “upper explosive limits;” these give the range of vapor concentrations in air that will explode if heat is added. Explosive limits are expressed as percent of vapor in air.
- Exposure Contact. No matter how dangerous a substance or activity, without exposure, it cannot harm you.
- Exposure routes A means by which a toxic substance can come into contact with or enter the body. The three major exposure routes are: inhalation (breathing), direct contact (touching), and ingestion (swallowing).
- Ex-situ Outside the original location. For example, contaminated that soil is dug up and removed before it is treated is being treated ex-situ. This is the opposite of in-situ.
- Exceedance Violation of the pollutant levels permitted by environmental protection standards.
- Extraction procedure (EP Tox Test) Determining toxicity by a procedure which simulates leaching; if a certain concentration of a toxic substance can be leached from a waste, that waste is considered hazardous, i.e., “EP Toxic.”
- Extraction well A discharge well used to remove contaminated groundwater or air.
- Feasibility Study (FS) A report examining the pros and cons of alternative methods to address contamination at a hazardous waste site. The feasibility study usually recommends a certain alternative. The FS is usually based on the results of a remedial investigation; together, they are commonly referred to as the RI/FS.
- Federal Register A weekly publication covering federal government activity including rule making, proposed plans, response to public comments, etc..
- Fill Man-made deposits of natural soils or rock products and waste materials.
- Fish and wildlife impact analysis Part of a remedial investigation that looks at the effects or potential effects of contamination on fish and wildlife.
- Flammable Catches on fire easily and burns rapidly.
- Flash point The lowest temperature at which the vapor of a substance will catch on fire, even momentarily, if heat is applied. Provides an indication of how flammable a substance is.
- Gas venting system A system of pipes and vents installed in a landfill to prevent the build up of landfill gases, such as methane, that could potentially explode. Sometimes the gas vents have flares on them to burn the gas as it is released into the atmosphere. At some very large landfills, the gas is collected and used to generate electricity.
- Geomembrane A low permeability plastic sheet that is placed over a landfill to deter rain and snow from entering a landfill’s waste. Geomembranes are often made from a plastic called HDPE (high density polyurethane). The geomembrane is covered with soil (barrier protection layer) and top soil to protect it.
- Geophysical surveys Techniques used to characterize the subsurface without having to dig up large areas. Examples include seismic refraction (commonly used to determine depth to bedrock), ground-penetrating radar (used to define sub-surface structures and buried objects), and magnetometry (used to detect buried iron objects).
- GeoprobeTM A special machine used to make soil borings and to create temporary groundwater monitoring wells.
- Gram(g) The unit of mass in the metric system. An ounce is about 28 grams, and a pound is approximately 450 grams.
- Granular activated carbon treatment A filtering system often used in small water systems and individual homes to remove organic compounds. See activated carbon.
- Groundwater Water found beneath the earth’s surface that fills pores between soil particles such as sand, clay, and gravel or that fills cracks in bedrock. Precipitation that does not evaporate or runoff to surface waters percolates downward through soil and becomes groundwater. Groundwater flows from areas of high elevation to low elevation at generally low velocities (usually ranging from 10-1000 feet/year) and eventually discharges into surface waters such as rivers, lakes, and wetlands. Groundwater often provides a source of drinking water via wells. The chemical composition of the groundwater reflects the soil or bedrock through which it passes; groundwater dissolves minerals in the soil and bedrock. If a source of contamination exists at or below the earth’s surface, percolating rainfall or snowmelt can transport contaminants downward where they can migrate with the groundwater.
- Groundwater collection/extraction and treatment system A system of wells fitted with pumps and piping used to pump out or extract contaminated groundwater from the subsurface. Properly designed and operated systems can effectively contain a groundwater contaminant plume and prevent further contaminant migration.
- Groundwater table See Water Table Half-life (1) The time required for a pollutant to lose half its effect on the environment. (2) The time required for half of the atoms of a radioactive element to undergo decay. (3) The time required for the elimination of one half a total dose from the body.
- Hammer mill- A high-speed machine that uses hammers and cutters to crush, grind, chip, or shred solid waste.
- Hazardous ranking system(HRS)- A scoring system used to evaluate potential relative risks to public health and the environment from releases or threatened releases of hazardous materials. EPA and States use the HRS to calculate a site score (0 to 100) based on the actual or potential release of hazardous materials from a site through air, surface water, or groundwater. This score is the primary factor used to decide if a hazardous waste site should be placed on the National Priorities List.
- Hazardous Substance- (1) Under the Comprehensive Environmental Response, Compensation, and Liability Act, a hazardous substance is any element, compound, mixture, solution, or substance that, when released to the environment, may present a substantial danger to the public health or welfare or to the environment, including, but not limited to, toxic and certain other pollutants under the Federal Water Pollution Control Act, Resource Conservation and Recovery Act, hazardous air pollutants regulated by parts of the Clean Air Act, and Toxic Substance Control Act. The term is much broader than the term hazardous waste. Sites that contain only hazardous substances are excluded from New York’s Superfund program. (2) Any substance designated reportable by the EPA if a designated quantity of the substance is spilled in the waters of the United States or if it is otherwise emitted to the environment.
- Hazardous Substance Site- A site that contains hazardous substances but does not contain hazardous waste. Therefore, it cannot receive funding or attention from the State’s Superfund program.
- Hazardous waste(s)- By-products of society that can pose a substantial or potential hazard to human health or the environment when improperly managed. To be considered hazardous waste, the waste must possess at least one of four characteristics (ignitability, corrosivity, reactivity, or toxicity) or appear on special EPA lists.
- Hazardous waste site- A place where hazardous wastes have been dumped, buried or improperly stored. Sites range from a crest of land containing thousands of tons of chemical wastes to a few drums of solvents dumped in a vacant lot. See also inactive hazardous waste disposal site.
- Health and safety plan A plan included in investigation or cleanup work plans which outlines protective measures for site workers and the community during investigation or cleanup activities.
- Health hazard Anything which can have harmful effects on health. There can be both acute and chronic health hazards.
- Health risk assessment A process which estimates the likelihood that people who could be exposed to chemicals may have health effects. The four steps of a risk assessment are: (1) hazard identification (Can this substance damage health?), (2) dose-response assessment (What dose causes what effect?), (3) exposure assessment (How and how much do people contact it?), and (4) risk characterization (combining the other three steps to estimate risk).
- Heavy metals Metals with high atomic weights, such as mercury, chromium, cadmium, arsenic, and lead. They can damage living things at low concentrations and tend to accumulate in the food chain.
- Herbicide A chemical used to control, suppress, or kill plants, or to severely interrupt their normal growth process.
- Heterogeneous Consisting of dissimilar ingredients or constituents.
- Homogeneous Having a uniform consistency or ingredients; composed of similar ingredients.
- Hydraulic Operated, moved or effected by means of water.
- Hydraulic conductivity The rate at which water can move through apermeable medium.
- Hydraulic gradient In general, the direction of groundwater flow due to changes in the depth of the water table. Just as water flows downhill, water in the ground moves from areas of high elevation to areas of low elevation. The slope of the water table is the hydraulic gradient. The hydraulic gradient determines the speed of groundwater flow. A steep gradient causes groundwater to mover faster than a nearly horizontal gradient.
- Hydrocarbon Any of a series of chemical compounds that consist entirely of carbon and hydrogen.
- Hydrogen Release Compound (HRCTM) Hydrogen Release Compound (HRCTM) is a passive treatment option for bioremediation of chlorinated solvents. HRCTM is injected into contaminated soils. Naturally occurring microbes metabolize lactic acid released by HRCTM, and produce hydrogen. The resulting hydrogen can be used to break down the chlorinated solvents. The process requires anaerobic conditions. Major target compounds include perchloroethene, trichloroethene, and trichloroethane as well as their breakdown products.
- Hydrogeologic testing Physical tests performed to obtain specific groundwater and geologic data. A pump test, for example, is used to determine the permeability (a measure of how readily groundwater flows) and storage capacity (a measure of the amount of water available) of an aquifer.
- Hydrogeology The geology of groundwater, with particular emphasis on the chemistry and movement of water.
- Hydrology The study of the movement and properties of water on the earth’s surface, underground and in the atmosphere.
- Impermeable Unable to be penetrated, as by liquids. For example, an “impermeable membrane” can be a thin plastic sheet through which rainwater cannot move.
- Inactive hazardous waste disposal site A hazardous waste site where disposal of hazardous wastes has been confirmed and wastes are no longer being disposed of there (“inactive” site). Incineration Burning of certain types of solid, liquid, or gaseous materials under controlled conditions to destroy hazardous wastes.
- Infiltration The penetration of water through the ground surface into sub-surface soil or the penetration of water from the soil into sewer or other pipes through defective joints, connections, or manhole walls. (See: percolation.)
- Influent Water, wastewater, or other liquid flowing into a reservoir, basin, or treatment plant. The opposite of effluent.
- Ingestion Swallowing. This is one way a person can be exposed to chemicals.
- Inhalation Breathing. This is one way a person can be exposed to chemicals.
- Inorganic chemicals/compounds Chemicals that do not contain carbon.
- In-Situ In the original place. In-situ treatment is carried out at a hazardous waste site without having to dig up and move the contaminated material. In-situ is the opposite of ex-situ. Insoluble Incapable of being dissolved in water or another liquid.
- Institutional controls A variety of methods used to control access to a contaminated site and/or exposure to contaminants at a site. Examples of institutional controls include fencing or deed notifications/ restrictions.
- Interim remedial measure(s)(IRM) Action(s) that can be conducted at a site relatively quickly to reduce the risk to people’s health and the environment from a well-defined hazardous waste problem. An IRM can involve removing contaminated soil and drums, providing alternative water supplies or securing a site to prevent access.
- Land Disposal Restrictions (LDR’s) Federal rules that require hazardous wastes to be treated before disposal on land to destroy or immobilize hazardous constituents that might migrate into soil and groundwater.
- Landfill Any place where wastes were disposed of by dumping waste and covering it. There are three main kinds of landfills: (1) Sanitary landfills are disposal sites for nonhazardous solid wastes at which the waste is spread in layers, compacted to the smallest practical volume, and covered with material at the end of each operating day. (2) Secure chemical landfills are disposal sites for hazardous waste. They are selected and designed to minimize the chance of release of hazardous substances into the environment. (3) Old landfills were built without modern day protections; these may contain hazardous wastes. Many of these landfills are being investigated and cleaned up under the State’s remediation program.
- Landfill cap/landfill cover system A layering of material over a landfill to deter rain and snowmelt from moving through the waste pile. A typical landfill cover will include a geomembrane or a layer of clay covered with a layer of low permeability soil, which in turn is covered by a layer of topsoil and seeded to encourage grass to grow. Landfill cover systems can also include gas vents to prevent gases such as methane from building up inside the landfill. The cover system is designed so rain and snowmelt is directed into a drainage ditch or swale.
- Landfill gas As organic wastes within a landfill break down, gases such as methane and hydrogen sulfide are produced. The production of these gases drops off over time.
- Leachate Surface or groundwater that is contaminated while moving through a landfill’s wastes.
- Leachate collection system A system that gathers leachate and pumps it to the surface for treatment.
- Light non-aqueous phase liquid (LNAPL) Liquids lighter than water that represent a special class of soil and groundwater contaminants with unique behavior and problems. See also NAPL. Liner A relatively impermeable barrier designed to keep leachate inside a landfill. Liner materials include plastic and dense clay.
- List / listing When DEC adds a hazardous waste site to the Registry of Inactive Hazardous Waste Disposal Sites, this is called “listing” a site.
- Liter The unit of volume in the metric system. A liter is about the same as a quart.
- Low Temperature Thermal Desorption The process of heating soil anywhere between 200 and 1000°F in order to vaporize contaminants with low boiling points. The vaporized contaminants are collected and treated. The low temperatures requires less fuel than other treatment methods.
- Magnetometer/magnetometer survey A magnetometer is an instrument that can detect metal objects buried underground. When this instrument is used to look for buried drums or other metal objects at a hazardous waste site, this is called a magnetometer survey.
- Maximum contaminant level The maximum permissible level of a contaminant in water delivered to any user of a public water system. MCLs are enforceable standards.
- Media/medium Specific environments that can contain contaminants. Air, water, sediment and soil are media.
- Metals A number of chemical elements that share certain special characteristics. Many metals can be toxic in high doses and can bioaccumulate in the food chain. Metals sometimes found at hazardous waste sites include: arsenic, barium, cadmium, chromium, copper, lead, mercury, nickel, silver, and zinc.
- Methane An odorless gas produced in newer landfills as organic material (previously living things or material derived from living things) breaks down. Methane production drops off as a landfill gets older.
- Methylene chloride A colorless nonflammable liquid, with a pleasant aromatic odor, used as a solvent, paint remover, and degreaser.
- Micrograms per kilogram (ug/kg) A way of expressing dose: micrograms (ug) of a substance per kilogram (kg) of body weight or soil.
- Micrograms per liter (ug/l) A unit of measure: the number of micrograms of one substance in a liter of liquid. One microgram per liter means one microgram of chemical per liter of water, and is essentially equivalent to one part per billion (ppb). Theoretically one ug/l of a substance equals one part per billion of the substance multiplied by its density.
- Milligrams per kilogram (mg/kg) A way of expressing dose: milligrams (mg) of a substance per kilogram (kg) of body weight or soil.
- Milligrams per liter (mg/l) A unit of measure: the number of milligrams of one substance in a liter of liquid. One milligram per liter means one milligram of chemical per liter of water, and is essentially equivalent to one part per million (ppm) at very low concentrations. Theoretically one mg/l of a substance equals one part per million of the substance multiplied by its density.
- Monitored Natural Attenuation Natural attentuation that is expected to achieve site cleanup objectives within a time frame that is reasonable compared to more active cleanup methods. The natural attenuation processes are carefully monitored. Monitored Natural Attenuation is used in combination with “source control” or removing the contamination source as far as practicable.
- Monitoring well (1) A well used to obtain water quality samples or measure groundwater levels. (2) A well drilled to collect groundwater samples for testing to determine the amounts, types, and distribution of contaminants in the groundwater beneath the site. The well enables samples of groundwater to be collected at a specific horizontal and vertical location for chemical analysis. Sometimes soil samples are also collected as the well is being drilled.
- National Priorities List (NPL) The U.S. Environmental Protection Agency’s list of the most serious uncontrolled or abandoned hazardous waste sites identified for possible long-term remedial response using money from a special trust fund (Superfund).
- Natural attenuation Relying on natural (physical, chemical, or biological) processes to reduce mass, toxicity, mobility, volume or concentration of compounds in earth or groundwater. Under proper conditions, can be used for perchloroethylene (PCE), trichloroethylene (TCE), and trichloroethane (TCA) at a lower cost than conventional remediation technologies.
- New York State Department of Health Agency within the executive branch of New York State government which: determines potential risk from environmental exposure at hazardous waste sites; conducts health-related community outreach around sites; and reviews remedial actions to assure that public health concerns are addressed.
- New York State Department of Law Agency within the executive branch of New York State government which takes the lead on hazardous waste site litigation. Litigation can involve negotiations and court action with responsible parties to clean up sites; natural resources damage claims, and recovery of remedial costs.
- New York State Registry of Inactive Hazardous Waste Disposal Sites See Registry of Inactive Hazardous Waste Disposal Sites in New York State
- Non-aqueous phase liquids (NAPL) Liquids, commonly a mixture of several different chemicals, that are either denser or less dense than water.
- Dense NAPL (DNAPL), such as chlorinated solvents, will sink if it enters groundwater; less dense, or light NAPL (LNAPL), such as gasoline, will float on the water table. NAPL in the subsurface can be a persistent source of groundwater contamination due to its low solubility and viscosity.
- Occupational exposure limits Maximum allowable concentrations of toxic substances in workroom air for workers.
- Odor threshold The lowest concentrations of a substance’s vapor, in air, that can be smelled. Odor thresholds are highly variable, depending on the individual who breathes the substance and the nature of the substance.
- Operable unit An administrative term used to identify a portion of a site that can be addressed by a distinct investigation and/or cleanup approach. For example, groundwater contamination at a site may be considered as one operable unit, and soil contamination at the same site may be dealt with as a second operable unit. An operable unit can receive specific investigation, and a particular remedy may be proposed. A Record of Decision is prepared for each operable unit.
- Operation and maintenance (O&M) The period following construction of a remedy during which elements of the remedy must be operated and maintained. For example, after a groundwater collection and treatment system is installed (the remedial construction phase), operation of the groundwater collection system and treatment of the water would be part of the “Operation and Maintenance” phase of the remedial program. Activities could also include site inspections, groundwater well monitoring and other sampling.
- Order on Consent See Consent Order Organic (1) In chemistry, any compound containing carbon. (2) Referring to or derived from living organisms.
- Organic compounds Chemicals that contain carbon. Overburden The rock and soil in the ground above bedrock.
- Oxidizer (1) A substance (compound) that will accept electrons from another compound, thus changing (oxidizing) the other compound. (2)A material which may cause combustible materials to ignite without the aid of an external ignition source (such as flame) or which, when mixed with combustible materials, increases the rate of burning of these materials. Part 360 New York State landfill regulations, including some regulations related to old landfills that contain hazardous waste.
- Part 375 The portion of New York State regulations governing inactive hazardous waste disposal sites.
- Particulates Fine liquid or solid particles such as dust, smoke, mist, fumes, or smog, found in air or emissions.
- Parts per billion (ppb) The concentration of a substance of air, water or soil. One ppb means that there is one part of a substance for every billion parts of the air, water or soil in which it is measured. One ppb is about one drop of dye in 18,000 gallons of water or about one second in 32 years. One ppb is 1,000 times less than one part per million.
- Parts per million (ppm) The concentration of a substance in air, water or soil. One ppm means that there is one part of a substance for every million parts of the water or soil in which it is measured. One ppm is about one drop of dye in 18 gallons of water, about one inch in 16 miles, or one penny in $10,000.
- Parts per trillion (ppt) The concentration of a substance in air, water or soil. One ppt means that there is one part of a substance for every trillion parts of the water or soil in which it is measured. One ppt is 1,000 times less than one part per billion.
- PCBs (polychlorinated biphenyls) A group of toxic, persistent chemicals used in transformers for insulating purposes, in gas pipeline systems as a lubricant, and in some florescent light ballasts. The sale of PCBs was banned by law in 1979, but many old transformers still contain them.
- Perchloroethene See Tetrachloroethene Percolate/ percolation The movement of water through a porous substance such as soil. Permeable/ permeability The rate at which liquids pass through soil or other materials in a specified direction. Water moves easily through a “high permeability” soil (such as gravel) and very slowly through a “low permeability” soil (such as clay). Pesticide Substance or mixture of substances intended for preventing, destroying, repelling, or mitigating any pest. Some pesticides can accumulate in the food chain and/or contaminate the environment if misused. pH A measure of the acidity or alkalinity (how basic) of a liquid or solid material. It is related to the number of hydrogen ions in a substance.
- Photo ionization detector (PID) A hand-held instrument used to measure the overall level of volatile organic compounds in air.
- Piezometer An instrument used to measure the elevation of the water table, i.e. how far below the surface groundwater is located.
- Plume An area of chemicals moving away from its source in a feather-like (hence the name, plume) shape. A plume, for example, can be a column of smoke drifting away from a chimney. An area of dissolved chemicals moving with groundwater is called a “groundwater contaminant plume.”
- Polychlorinated biphenyls See PCBs Polycyclic aromatic hydrocarbons(PAHs) A group of over 100 different chemicals that form during the incomplete burning of coal, oil and gas, garbage, or other organic substances like tobacco or charbroiled meat. PAHs are usually found as a mixture containing two or more of these compounds, such as soot. Some PAHs are manufactured. PAHs are found in coal tar, crude oil, creosote, and roofing tar, but a few are used in medicines or to make dyes, plastics, and pesticides. Most do not dissolve easily in water and stick tightly to soil particles.
- Polynuclear aromatic hydrocarbons (PAHs) See polycyclic aromatic hydrocarbons
- Porosity The percentage of the total volume of a given body of rock that is pore space. It is the portion of void (air) space in rock, soil, or sediment.
- Potable Drinkable.
- Potentially responsible party (PRP) Persons identified by the EPA under CERCLA or by New York State law as being responsible for the contamination at a hazardous waste site. By law, PRPs may be generators, present or former owners or operators of a site, or transporters of the hazardous substances.
- PRAP See Proposed Remedial Action Plan
- Precipitation (1) Rain or snow. (2) Removal of solids from liquid waste so that the hazardous solid portion can be disposed of safely.
- Preliminary site assessment (PSA) A PSA is the Division of Environmental Remediation’s first investigation of a site. A PSA is performed to determine if a site meets New York State’s definition of an inactive hazardous waste disposal site by confirming the presence of hazardous waste and determining if the site poses a significant threat to public health or the environment.
- Presumptive remedy Cleanup technique(s) that can be applied to hazardous waste sites with common characteristics. For example, old municipal landfills built without a liner often have similar characteristics. EPA has developed a “presumptive remedy” for this type of site. Essentially, EPA said “Here’s a site similar in all key ways to many other sites we’ve cleaned up. Wouldn’t it make sense to use that cleanup approach here too?”
- Project manager A DEC staff member within the Division of Environmental Remediation (usually an engineer, geologist, or hydrogeologist) responsible for the remedial program at a hazardous waste site. The project manager works with the Division of Public Affairs and Education, fiscal and legal staff and the Department of Health to accomplish site-related goals and objectives.
- Proposed Remedial Action Plan (PRAP) A document outlining alternatives considered by the Division of Environmental Remediation for the remediation of a hazardous waste site and highlighting the alternative preferred by DEC. The PRAP is based on information developed during the site’s Remedial Investigation and Feasibility Study. The PRAP is reviewed by the public and other state agencies.
- Public hearing A formal hearing at which the public has the opportunity to submit comments and testimony on proposed actions for the public record.
- Public meeting A scheduled gathering of DEC staff and the public to give and receive information, ask questions and discuss concerns.
- Publicly owned treatment works (POTW) A wastewater system, owned by a municipality, state, or tribe that is used for the collection, treatment, and/or disposal of sewage. Usually POTW refers specifically to the sewage treatment plant.
- Pump and treat A method used to collect and treat contaminated groundwater. Typically, groundwater is collected in a well or trench and pumped to a treatment system.
- Quality assurance (QA)/ quality control (QC) A system of procedures, checks, audits, and corrective actions to ensure that environmental sampling and testing are of the highest achievable quality.
- Reactivity The ability of a substances to undergo change, usually by combining with another substance or by breaking down. Certain conditions, such as heat and light, may cause a substance to become more reactive. Highly reactive substances may explode.
- Real-time monitoring During construction or investigation activities, continuous monitoring of air with equipment that gives immediate read-outs; that is, samples don’t need to be sent to a laboratory to obtain results.
- Recharge The replenishment of groundwater by infiltration of rain and snow through the soil.
- Reclassification A process by which the Division of Environmental Remediation redefines the threat posed by a hazardous waste site to public health and the environment by developing and assessing site information and, based on findings and conclusions, assigning the site a new classification code (see Site Classification.
- Record of Decision (ROD) A document which provides the definitive record of the cleanup alternative that will be used to remediate a hazardous waste site. The ROD is based on the Remedial Investigation / Feasibility Study and public comment.
- Registry of Inactive Hazardous Waste Disposal Sites in New York State Often referred to as “the Registry,” this is a compilation of all known and suspected hazardous waste sites (meeting certain criteria) in New York State. The Registry is compiled in a series of documents published every spring and can be purchased by the public. The document included a one page description and map of each site.
- Remedial/ remediate/ remediation Refers to any procedures or strategies used to address a hazardous waste site. For example, a Remedial Investigation determines what areas of a site need to be addressed (cleaned up or remediated), a proposed remedial action plan describes remedial actions (cleanup methods or corrective actions) that have been recommended for a specific site; remediation of a site could include removing contaminated soil.
- Remedial action (RA) Action taken to remove, destroy, reduce, or prevent the spread of contamination at a hazardous waste site.
- Remedial alternatives report (RAR) In New York State’s Brownfield program, a RAR is the equivalent of a feasibility study.
- Remedial construction (RC) The physical development, assembly and implementation of the alternative selected to remediate a site. For example, remedial construction could include installing a groundwater collection and treatment system. Construction follows a remedial design stage.
- Remedial design (RD) The process following finalization of a Record of Decision in which plans and specifications are developed for the implementation of the alternative selected to remediate (clean up) a site.
Remedial Investigation (RI) Studies designed to gather the data necessary to determine the type (nature) and extent (location) of contamination at a hazardous waste site. The RI is usually performed at the same time as a Feasibility Study in a process known as the “RI/FS.” This process is designed to:
- Establish criteria for cleaning up the site.
- Identify and screen cleanup alternatives for remedial action; and
- Analyze in detail the technology and costs of the alternatives.
- Remedial program DEC’s efforts to investigate and clean up inactive hazardous waste disposal sites. A remedial program is designed to correct or “cure”(remedy) releases or potential releases of hazardous materials into the environment. DEC takes several steps as part of each site’s remedial program: it investigates contamination (Remedial Investigation), analyzes different methods to address threats posed by the site (Feasibility Study), proposes a cleanup plan (Proposed Remedial Action Plan), selects a final plan (Record of Decision), and designs and implements the plan (Remedial Design andRemedial Construction).
- Remediation See remedial Remedy Actions taken to prevent or mitigate the release of hazardous materials into the environment at hazardous waste sites and brownfield sites. The word “remedy” is used in the sense of a “cure” or “corrective action.”
- Removal action Often less burdensome and extensive than remedial actions, a removal action is intended to be a quick, temporary response to a release or the threat of release of a hazardous material at a hazardous waste site. A removal action could involve removing drums of hazardous material, contaminated soil or contaminated sediment and taking these items to a proper disposal facility
- Residual / residue The quantity of a substance, its degradation products, and/or its metabolites remaining on or in the soil or groundwater. “Residual contamination” usually refers to low levels of chemicals that may be left in soil, bedrock or groundwater after cleanup of hazardous wastes.
- Resource Conservation and Recovery Act (RCRA) Federal law governing the treatment, storage, handling, disposal, and overall management of solid and hazardous wastes.
- Responsible parties See Potentially responsible parties Responsiveness summary A formal or informal written summary and response by the DEC to public questions and comments. A responsiveness summary is prepared following a public meeting about a Proposed Remedial Action Plan and may also be prepared after other public meetings. The responsiveness summary may list and respond to each question, or summarize and respond to questions in categories.
- Reverse osmosis A type of pressurized filtration system in which water is forced through a semipermeable membrane that allows the passage of water but restricts many contaminants.
- Riprap Large fragments of broken rock, thrown together irregularly or fitted together (as on the down-stream face of a dam). Its purpose is to prevent erosion by waves or currents and thereby preserve a surface, slope, or underlying structure. It is used for irrigation channels, river-improvement works, spillways at dams, and sea walls for shore protection.
- Risk The chance of an injury, illness, or death caused by exposure to a hazard.
- Risk assessment The qualitative and quantitative evaluation performed in an effort to define the risk posed to human health and/or the environment by the presence or potential presence and/or use of specific pollutants.
Record of DecisionSampling Small amounts of air, water, or soil are obtained and tested to determine the levels of different hazardous chemicals contained in them.
- Sanitary landfill See Landfill Saturated zone A subsurface area in which all pores and cracks in rock and/or soil are filled with water.
- Scrubber A device for removing unwanted gases or particles from an air stream by spraying the air with liquid (usually water) or forcing air through a series of baths. Scrubbers are often put on smoke stacks.
- Sediment Soil, sand, and minerals washed by rain from land into water that accumulates on the bottom of ditches, streams, rivers and lakes.
- Selected alternative (1) The cleanup alternative selected by the state as the most feasible. (2) The cleanup alternative selected for a site on the National Priorities List based on technical feasibility, permanence, reliability, and cost.
- Semi-volatile organic compounds (SVOCs) Chemicals similar to volatile organic compounds but that do not evaporate as readily. Polynucleated aromatic hydrocarbons are semi-volatile compounds.
Site classification DEC assigns inactive hazardous waste disposal sites classifications established by state law, as follows:
- Class 1- A site causing or presenting an imminent danger of causing irreversible or irreparable damage to the public health or environment – immediate action required.
- Class 2- A site posing a significant threat to the public health or environment – action required.
- Class 2a- A temporary classification for a site that has inadequate and/or insufficient data for inclusion in any of the other classes.
- Class 3- Site does not present a significant threat to the public health or the environment – action may be deferred.
- Class 4- A site which has been properly closed – requires continued management.
- Class 5- A site which has been properly closed, with no evidence of present or potential adverse impact – no further action required.
- Site Investigation/Remedial Alternatives Report (SI/RAR) In New York’s Brownfield program, this is the equivalent of a Remedial Investigation / Feasibility Study report. The site investigation is similar to a Remedial Investigation, and the Remedial Alternatives Report is similar to a Feasibility Study.
- Sludge A semi-solid residue from any of a number of industrial processes or air or water treatment processes. Sludge can be a hazardous waste.
- Slurry A watery mixture that does not contain a significant amount of dissolved materials.
- Slurry Wall An underground wall designed to stop groundwater flow; constructed by digging a trench and backfilling it with a slurry rich in bentonite clay.
- Soil boring A circular hole made in the ground by an auger or mechanical drill rig to collect soil samples deep in the ground. Representative samples are collected for testing to see if the subsoil has been contaminated. Sometimes these borings are converted into groundwater monitoring wells.
- Soil gas Air in the spaces between soil particles. Contaminants can be trapped in this air.
- Soil gas survey A method for investigating underground distributions of volatile organic compounds (VOCs) by looking for their vapors in the shallow soil gas. The presence of VOCs in shallow soil gas indicates the VOCs may be in the unsaturated (dry) soil or in the groundwater below the probe. This survey is used to trace the outline of a contaminant plume and help determine the best location to install groundwater monitoring wells.
- Soil Vapor Extraction System (SVE) An in-situ remediation technique that applies a vacuum to a series of wells (“vapor extraction wells”) and induces air flow through contaminated soil. As the air migrates through the soil, volatile organic compounds (VOCs) volatilize (evaporate) and move with the air to the extraction wells where they are removed from the subsurface. If the concentration of VOCs in the extracted air is high, the air maybe treated by a carbon adsorption system before being released to the atmosphere. In some cases, dual phase vacuum extraction is used to treat both groundwater and the overlying soil.
- Solid waste Non-liquid, non-soluble materials ranging from municipal garbage to industrial wastes that contain complex, and sometimes hazardous, substances. Solid wastes also include sewage sludge, agricultural refuse, demolition wastes, and mining residues.
- Solubility The amount of a substance that can be dissolved in water or (sometimes) another substance. Solvent A substance (usually a liquid) capable of dissolving one or more other substances. For example, paint remover is a paint solvent.
- Sorb To take up and hold by either adsorption or absorption.
- Source area An area from which groundwater contamination is believed to originate. For example, Company A spilled a 55 gallon drum of trichloroethene (TCE) onto the ground near a loading dock at their facility. The TCE spread through the soil and contaminated groundwater around the facility. Because the contamination originated in the loading dock area, this area is the “source area.” Over time, the highly concentrated TCE in the source area would continue to slowly spread through groundwater and soil, acting as a continuous “source” of groundwater contamination. Thus, the most effective way to slow down and prevent further spreading of contamination would be to address the source area.
- SPDES permit (pronounced SPEEDIES) See State Pollution Discharge Elimination System Split samples A soil sample from a hazardous waste site that is divided between the potentially responsible parties (PRPs) and the DEC or the Health Department. It functions as a system of checks and balances since both the PRPs and the DEC analyze their half of the sample. The results of the two analyses can then be compared.
- Split-spoon Sample A sample of unconsolidated material taken by driving a sampling device (split spoon) into the soil ahead of a drill bit in a soil boring. A split-spoon sampler is typically driven into the soil by repeatedly dropping a weight.
- Standards, criteria and guidance values (SCGs) Values that indicate acceptable or normal levels of various contaminants in the environment. These values are used to establish cleanup goals at hazardous waste sites. Depending on the chemical, the values are developed by the U.S. Environmental Protection Agency, DEC and/or the New York State Department of Health.
- State assistance contract (SAC) In DEC’s brownfield program, the official agreement between a municipality and the state that outlines both party’s responsibility for a brownfield investigation and/or cleanup.
- State Pollution Discharge Elimination System (SPDES) permit A permit issued by the DEC as part of the SPDES program, which is designed to maintain New York’s waters with reasonable standards of purity. State law requires a SPDES permit before construction or use of an outlet or discharge pipe for wastewater discharging into surface water or groundwater, and for construction or operation of disposal systems such as sewage treatment plants.
- Sump A pit or tank that catches liquid runoff for drainage or disposal.
- Superfund Federal and state programs to investigate and clean up inactive hazardous waste disposal sites. The federal program gives the U.S. Environmental Protection Agency the funding and authority to investigate, rank and con-duct or supervise cleanup of sites on the National Priority List. New York State’s program gives DEC the same authority to deal with sites that do not qualify for the federal superfund list, but meet certain other qualifications.
- Superfund Amendments and Reauthorization Act (SARA) Modifications to CERCLA enacted in 1986. Sometimes referred to as the “Right to Know Law,” it requires, among other things, that industry provide the government with information on the use and release of certain chemicals into the environment. This information is then made available to the public.
- Surface water All water naturally open to the atmosphere. Refers to water in rivers, lakes, reservoirs, streams, impoundments, seas, estuaries, and so on.
- Swale A slight depression, sometimes swampy, in the midst of generally level land.
- Technical and Administrative Guidance Memorandum (TAGM) An official internal Division of Environmental Remediation document that outlines divisional policies or recommended guidance for topics such as determining cleanup goals at hazardous waste sites.
- Technical Assistance Grant Program (TAG Program) A federal grant program that provides funds for qualified citizens’ groups to hire independent technical advisors to help them understand and comment on technical decisions relating to federal Superfund cleanup actions.
- Technical and Operational Guidance Series (TOGs) DEC Division of Water’s documents listing water quality standards and guidance values.
- Test pit A small excavation at a hazardous waste site. Investigators dig test pits to get an idea of subsurface conditions at hazardous waste sites.
- Tetrachloroethene (Perchloroethene) A clear, colorless, non-flammable liquid with a characteristic odor. It is a widely used solvent, especially as a dry cleaning agent and as a degreaser.
- Threshold A dose or exposure below which there is no measurable adverse effect.
- Title 3 program/project Part of New York State’s Superfund program whereby the State pays 75 percent of eligible costs for remediation of municipally owned hazardous waste sites and the municipality pays 25 percent.
- Toxicity The degree of danger posed by a substance to animal or plant life.
- Toxicity Characteristic Leaching Procedure Laboratory test used to determine the mobility of organic and inorganic contaminants present in liquid, solid, and multiphase wastes. If an extract from a representative sample is shown to contain any contaminant in an amount exceeding the levels allowed by regulations, the waste is banned for land disposal unless properly treated.
- Toxic substances A chemical or mixture that may present an unreasonable risk of injury to health or the environment.
- Toxic Substances Control Act (TSCA) of 1976 A federal law that provides for testing of manufactured substances to determine toxic or otherwise harmful characteristics and regulation of the manufacture, distribution, use, and disposal of regulated substances.
- Treatability studies (1) Tests of potential cleanup technologies conducted in a laboratory. (2) Pilot-scale type tests conducted at hazardous wastes sites to determine if a treatment technology will work for that site’s particular set of environmental conditions.
- Treatment, storage, and disposal facility(TSDF) A site where a hazardous substance is treated, stored or disposed of. TSDF facilities are regulated by EPA and states under the Resource Conservation and Recovery Act.
- 1,1,1-Trichloroethane (1,1,1 TCA) Colorless, non-flammable, man-made liquid solvent used as a degreaser, a dry-cleaning agent, and a propellant.
- Trichloroethene or Trichloroethylene (TCE) A colorless, man-made liquid used primarily as a solvent for removing grease from metal. It has a variety of other uses such as a dry cleaning solvent and in the production of other chemicals. It generally gets into drinking water by improper waste disposal.
- Unconfined aquifer An aquifer in which water is not contained by an impermeable layer of rock or soil. The water level in the aquifer may rise or fall according to the volume of water stored, which varies according to seasonal cycles of natural recharge.
- Unsaturated zone The area of soil and rock between the land surface and the water table. The spaces between soil particles (pore spaces) in the unsaturated zone contain mostly air, but water occurs there as soil moisture.
- Vadose zone The underground zone between the land surface and the water table; essentially the unsaturated zone.
- Vapor The gas given off by a solid or liquid substance at ordinary temperatures.
- Vinyl chloride A colorless gas used in the manufacture of polyvinyl chloride and other resins, and as a chemical intermediate and as an industrial solvent. Vinyl chloride is a carcinogen. Viscosity The property of a fluid describing its resistance to flow.
- Volatile Description of any substance that evaporates easily.
- Volatile organic compounds (VOCs) Carbon-containing chemicals which readily evaporate (cleaning solvents, gasoline, etc.). Many common industrial chemicals are VOCs, including trichloroethene, 1,1,1-trichloroethane, and tetrachloroethene.
- Voluntary cleanup agreement A legal document signed by DEC and another party (volunteer) for investigation and/or cleanup of a contaminated site. In return for cleaning up the site, the volunteer receives a limited liability release for past environmental contamination of the site.
- Voluntary cleanup program A program designed to promote voluntary cleanup of contaminated sites including inactive hazardous waste sites, hazardous substance sites, petroleum contaminated sites and solid waste disposal sites, whereby the volunteer enters into a Voluntary Cleanup Agreement with the DEC.
- Waste (1) Unwanted materials left over from a manufacturing process. (2) Refuse from places of human or animal habitation.
- Water-bearing zone The area underground in which pores and cracks in rock and/or soil are normally filled with water. Therefore, if a well is drilled into this area, water can be drawn out on a regular basis.
- Water table The level of groundwater; the boundary between the unsaturated zone and the saturated zone.The water-table generally reflects surface topography and varies with changes in land surface elevations.
- Weir (1) A wall or plate in a open channel to measure the flow of water. (2) A wall or obstruction used to control flow from settling tanks, clarifiers, or a drainage system to ensure a uniform flow rate.
- Wetlands An area that is regularly saturated by surface water or groundwater. Examples of wetlands include swamps, bogs, fens, marshes, and estuaries.
Glossary of Terms – From the Massachusetts Department of Environmental Protection
- Absorption- The process whereby one substance is physically taken into and included within another substance, as the absorption of water by soil.
- Additive- Any solid or liquid material or biological agent marketed primarily for cleaning, treating, degreasing, unclogging, disinfecting, deodorizing or otherwise affecting the performance of any component of an on-site system.
- Adsorption- Attachment of a substance to the surface of a solid, such as soil particles or sediment. Many different pollutants can adsorb to soil particles.
- Aerobic System- I/A technologies that use aerobic bacteria (bacteria that require oxygen) to treat wastewater and reduce organic material.
- Aggregate- Stones of various sizes surrounding soil absorption system. Allows growth of aerobic sewage treatment bacteria.
- Alternating Bed Systems- Also known as an alternating leach field. An absorption system designed with a backup absorption field for use while the primary absorption field rests.
- Approving Authority- Local Boards of Health are the primary regulatory authorities.
- As-Built Plan- Plan that depicts an on-site system (including dimensions, distances from dwellings, roads, surface water, wells) as it was built by a licensed installer.
- Backwash- Wastewater generated from the cleaning of water and wastewater treatment filters.
- Betterment- Financial agreement (loan) between a community and homeowner to repair, replace and/or upgrade the on-site system itself, or to hook up to existing sewers.
- Biodegradation- Takes place in on-site system soil absorption system (SAS). Organic compounds are broken down into carbon dioxide, water and minerals by the action of microorganisms such as bacteria.
- Blackwater- Wastewater from toilets, urinals, and sinks with garbage disposals.
- Buffer- Areas of vegetation left undisturbed or planted between a developed area and a waterbody. Buffer vegetation includes trees, shrubs, bushes and ground cover plants.
- Centralized Wastewater System- Managed system of collection sewers and a single treatment plant to collect and treat wastewater from an entire service area, in contrast to a system that treats effluent on-site (conventional septic system, innovative/alternative (I/A) system, or cesspool).
- Certificate of Compliance- Certificate issued by the Board of Health to the owner or operator of a system in accordance with 310 CMR 15.021 indicating that an on-site system has been constructed or upgraded, and inspected in compliance with Title 5.
- Cesspool- Pit acting as a settling chamber for solids and leaching for liquids. Cesspools that pose a threat to public health, safety or the environment must be upgraded.
- Cluster System- Wastewater collection and treatment system under some form of common ownership, which collects wastewater from two or more dwellings or buildings and conveys it to a treatment and disposal system that is located nearby.
- Commercial System- Serves a commercial establishment (e.g., retail/office, restaurant or industrial) rather than a residence. Commercial systems serving restaurants and other food preparation facilities must include a grease trap to remove greases and oils before they enter the septic tank (310 CMR 15.230).
- Composting Toilet- Technology that uses a biological process to degrade human waste into a humus-like end product.
- Conventional Pressure Distribution System- On-site wastewater treatment system consisting of a septic tank and a subsurface soil absorption system that relies on pressure distribution of the effluent. Click here for more information.
- Conventional Septic System- On-site wastewater treatment consisting of septic tank and a trench or bed subsurface soil absorption system, which relies on gravity to distribute effluent.
- Conveyance Lines- Pipes that connect the various parts of a septic/on-site system (e.g., building sewer, septic tank, distribution box).
- Cover Material- Soils placed on top of a soil absorption system to bring the area to finish grade.
- Creeping Failure- Condition in which the biomass of a soil absorption system becomes so intensely developed that no water can flow through it, eventually causing system malfunction.
- Decentralized System- On-site and/or cluster system used to collect, treat, and disperse or reclaim wastewater from a small community or service area.
- Decentralized Wastewater Management- Active oversight of multiple on-site or cluster wastewater treatment systems in a state or local area through regulatory control, licensing, financing assistance and other means, with the intention of protecting the environment and public health, and achieving water quality goals.
- Deep Observation Hole- Open pit dug to permit examination of the soils and to obtain data relative to the mean annual high groundwater elevation and depth to impervious materials.
- Design Flow- Quantity of sanitary sewage in gallons per day (gpd) for which a system must be designed in accordance with 310 CMR 15.203.
- Design Life- Estimated length of time before a system will have to be replaced or rehabilitated. Septic systems have a design life of 20-30 years, given proper siting, construction, and maintenance.
- Disposal System Construction Permit- Written approval by local Board of Health authorizing the construction, upgrade, or expansion of an on-site system.
- Distribution Box- Level, watertight structure which receives septic tank effluent and distributes it in substantially equal portions to two or more lines leading to a leaching area.
- Distribution Line- Pipe used for dispersion of septic tank effluent into leaching trenches or leaching fields.
- Dosing Tank- Watertight structure placed between a septic tank and either a distribution box or a soil absorption system, equipped with a pump designed to discharge septic tank effluent to the soil absorption system and to provide a rest period between such discharges.
- Drainfield- See Soil Absorption System.
- Drywell- Pit with open-jointed lining or holes through which stormwater drainage from roofs, basement floors, foundations, or other areas seeps into the surrounding soil.
- Effluent- Sanitary sewage discharged into the environment, whether treated or not.
- Effluent Filter- Filter placed at the outlet of the septic tank to trap suspended solids that are not heavy enough or have had insufficient time to sink to the bottom of the tank.
- Fill- Clean, uncontaminated, non-indigenous soil placed beneath, above and/or around a soil absorption system.
- Flow Diversion Valve- Alternates the flow from the septic tank to one portion of the absorption field while restricting flow to other portions, allowing different parts of the absorption field to be used while other portions rest and recover.
- General Use Certification – Approval for innovative/alternative (I/A) technologies that can be used statewide at any site where a conventional Title 5 system can be installed without review and approval of the system design by MassDEP.
- Grease Trap- Watertight structure located on a building sewer and before a septic tank in which grease and oils are separated from sewage.
- Greenbelt- Area of open space that creates a boundary for development and preserves natural, agricultural, recreational and scenic corridors.
- Greywater- Domestic wastewater from all sources except toilets, urinals, and drains equipped with garbage disposals. Sources include washing machines, sinks, showers, bathtubs, and dishwashers.
- Groundwater- Fresh or saline water beneath the ground surface contained in spaces between rock and soil particles and bedrock fractures.
- Groundwater Elevation- Elevation at which water is observed weeping or flowing from the walls of, or standing in, a deep observation hole.
- Hydraulic Overload- Excessive flows of wastewater that upset the capability of the on-site treatment system to properly treat wastewater.
- Impervious Material- Material having a percolation rate greater than 60 minutes per inch, including, but not limited to bedrock, peat, loam, silt, clay and organic matter.
- Industrial Waste- Any water-carried or liquid waste resulting from any process or industry, manufacture, trade, business, or activity listed in (310 CMR 15.004).
- Infiltration Capacity- Maximum rate at which water can infiltrate into soil under a given set of conditions.
- Infiltration Rate- Rate at which water penetrates the surface of the soil at any given moment, usually expressed in inches per hour.
- Inlet and Outlet Tees- Device on inlet and outlet ports of septic tank. The sanitary tee pipe at the tank inlet slows the incoming rush of water to prevent disturbance to the scum layer and reduce turbulence. The sanitary tee pipe located at the tank’s outlet keeps solids, scum and grease from leaving the tank and entering the soil absorption system.
- Innovative/Alternative (I/A) System- Any on-site wastewater disposal system or part of one that differs from the design or construction of a conventional, or standard on-site system. A conventional, or standard, system has a septic tank, distribution box or dosing mechanism, a soil absorption system (SAS), and a reserve area.
- Large Capacity Septic System- On-site system having the capacity to serve 20 or more persons per day subject to EPA’s Underground Injection Control regulations.
- Leach Field- See “Soil Absorption System.”
- Local Upgrade Approval- Variations of Title 5 that allow system owners to upgrade a nonconforming system to the maximum extent feasible (310 CMR 15.401-405).
- Long Term Acceptance Rate (LTAR)- Stable rate of effluent acceptance through the biological mat of a soil absorption system measured in gallons per day per square foot (gpd/sf) (310 CMR 15.242).
- Management Model- Program consisting of thirteen elements designed to protect and sustain public health and water quality. This effort is focused on ensuring that on-site and cluster wastewater treatment systems are appropriately managed throughout their life cycle.
- Maximum Feasible Compliance- If a failed on-site system cannot be fully upgraded to full compliance with Title 5, the Local Board of Health is authorized to approve an upgrade to bring the system as close to compliance as possible (310 CMR 15.404).
- Mounded System- Systems that are constructed in fill, which extends either wholly or partially above natural grade for purpose of complying with the required four or five foot separation to groundwater (310 CMR 15.212).
- New Construction- Either a new building or building expansion that causes an increase in design flow above the approved capacity of a system. It does not include any construction that does not include increase in flow.
- Nitrogen Reducing Technologies- I/A treatment systems that reduce nitrogen by creating conditions that promote nitrification – the conversion of ammonia (NH3) to nitrate (NO3), followed by denitrification – the conversion of nitrate to inert nitrogen gas (N2). The I/A systems qualifying for a nitrogen reduction credit under Title 5 must be able to reduce nitrogen in wastewater to 19-25 mg/liter from an average influent concentration of 40 mg/liter.
- Nitrogen Sensitive Area- An area designated by MassDEP in accordance with 310 CMR 15.215 [310 CMR 15.215], because of its particular sensitivity to the discharge of nitrogen from on-site sewage disposal systems, including drinking water supply areas.
- Nonpoint Source Pollution- Pollution that comes from diffuse or multiple sources, such as nutrients and bacteria from a malfunctioning on-site system
- On-site System- Treatment and disposal system for sanitary sewage. On-site systems include conventional septic systems, innovative/alternative (I/A) technologies, and cesspools.
- Operating Permit- Renewable and revocable permit to operate and maintain an on-site or cluster treatment system in compliance with specific operational or performance requirements stipulated by the Board of Health.
- Owner- Person, who alone or together with another person(s), has legal title to any facility served by a system or control of the facility, including but not limited to any agent, executor, administrator, trustee, lessee or guardian of the estate for the holder of the legal title.
- Peat Filter System- I/A system that filters wastewater through 2-3 feet of peat, after the septic tank but before the soil absorption system (SAS).
- Perched Ground Water- Occurring when water, infiltrating the soil from above, reaches an underlying layer of impervious or relatively impervious soil that restricts its downward movement. Perched water can result from heavy rainfall and then disappear in a matter of hours, or the water may remain for months.
- Percolation Rate- The rate in which water is absorbed in a percolation hole, expressed in inches per minute.
- Percolation Test- A field test for determining the suitability of soil for the subsurface disposal of sewage
- Permeability- The relative ease (or lack thereof) with which water moves downward through soil. Permeability is measured in inches per hour. The permeability of soil is a critical factor in the suitability/sizing of a leach field for a particular site.
- Piloting Approval- Initial step in MassDEP’s 3-tier approval process for I/A technologies, requiring field testing and technical evaluation to demonstrate that the technology is likely to provide environmental protection equivalent to a conventional septic system.
- Pollutant- A contaminant that adversely alters the physical, chemical, or biological properties of the environment.
- Primary Treatment- In on-site systems, the initial treatment (separation of solids from liquids and limited biodegradation of contaminants) that occurs in the septic tank.
- Provisional Use Approval- Stage in MassDEP’s three-tier approval process for I/A technologies, typically occurring after successful piloting in Massachusetts or satisfactory past performance for two years of general use in one or more other states. Provisional use evaluates the technology’s performance under actual field conditions in Massachusetts.
- Recirculating Sand Filter (RSF)- A modified version of the old single-pass open sand filter designed to alleviate odor problems associated with dosing partially treated wastewater over a sand filter. A RSF must be used if the system’s design flow is 2,000 gpd and is located in a Nitrogen Sensitive Area.
- Remedial Use Approval- MassDEP approval of I/A technologies that can improve conditions at existing sites served by a failing, failed, or nonconforming system.
- Reserve Area- An area of land with demonstrated capacity for subsurface sewage disposal upon which no permanent structures shall be constructed. This land is intended to be used in case the principal system fails and needs replacing.
- Retention Time- Length of time effluent is retained in the septic tank. Effluent should be retained in the tank for at least 24 hours to receive adequate primary treatment (i.e., settling out of solids).
- Sanitary Sewage- Greywater and blackwater from domestic, commercial and other non-industrial sites.
- Scum- A mass of light solids, such as hair, grease, oils and soaps, floating on the surface of the wastewater in a septic tank.
- Septage- Material physically removed from any part of an on-site system; contents of septic system.
- Septage Hauler- Also known as a system pumper. Licensed by each Board of Health to pump on-site systems and dispose of the contents as part of regular system maintenance.
- Septic Tank- A watertight receptacle that receives sewage from a building and provides primary treatment (separation of solids and liquids and partial biodegradation).
- Shared System- A system sited and designed to serve more than one facility or more than one dwelling on a single facility and which has been approved in accordance with 310 CMR 15.290 – 15.293. A system serving a condominium unit or units located on the same facility is not a shared system.
- Sludge- The heavier solids that separate from wastewater inside the septic tank and sink to the bottom. These solids are subject to continual decomposition activity by bacteria in the tank; however, since breakdown is never complete, solids accumulate and must be periodically removed by pumping.
- Soil Absorption System (SAS)- Part of an on-site system: the area of ground and system of subsurface pipes or chambers into which partially treated wastewater from the septic tank or I/A system is discharged for final treatment and absorption by soil. Also called Leach Field, Drainfield or Absorption Field.
- Soil Evaluator- A person approved by MassDEP as capable of evaluating the suitability of soils at a specific site for the use of an on-site subsurface sewage disposal system.
- System Inspector- A person approved by MassDEP as being capable of appropriately assessing the condition of an on-site system.
- Test Pit- A hole dug in the proposed area for a leach field, to determine soil type, seasonal high water table and depth to bedrock.
- Tight Tank- A watertight vessel that has an inlet to receive raw sewage but no outlet. A tight tank is designed and used to collect and store sewage until it is removed for disposal.
- Title 5- On-site sewage disposal systems are governed by Title 5 of the Massachusetts State Environmental Code (310 CMR 15.000). Often erroneously written “Title V,” causing confusion with the Federal Clean Air Act.
- Trickling Filter- I/A treatment system in which wastewater trickles by gravity through a filter installed between the septic tank and the soil absorption system (SAS). The organic biomass on the filter media absorbs and oxidizes pollutants in the wastewater.
- Variance- Variation of Title 5 that occurs when an on-site system cannot meet full regulatory requirements and cannot be approved under a Local Upgrade Approval (310 CMR 15.410-20).
- Water Table- The level at which water stands in a shallow well open along its length and penetrating the surficial deposits just deeply enough to encounter standing water in the bottom.
- Wellhead Protection Areas- Areas of protection around a public drinking water supply