Category: Dictionary

Intermittent Water: A stream or reach that flows continuously only at certain times of the year, as when it receives water from rainfall or snow melt.

Interim Remedial Actions (IRA): Minimum remedial actions taken to address the loss or reduction of available water from a well until a remedy is selected.

Integrated Pest Management: The coordinated use of pest and environmental information with available pest control methods to prevent unacceptable levels of pest damage by the most economical means and with the least possible hazard to people, property, and the environment

Institutional Controls (ICs):  Actions, such as legal controls that help minimize the potential for human exposure to contamination by ensuring appropriate land or resource use. ICs are meant to supplement engineering controls, and they are rarely the sole remedy at a site. ICs are commonly used when residual contamination remains onsite at a level that does not allow for unrestricted use and unlimited exposure after cleanup.

In-Situ: In its original place; unmoved unexcavated; remaining at the site or in the subsurface.

Inorganic Compounds: Compounds that are considered to be of mineral as opposed to biological.

Injection Well: A well in which fluids are injected rather than produced as when treated water is put back into the aquifer after contaminants have been removed.

Infiltration: The flow of a fluid into a substance through pores or small openings.

Impervious Surface: A surface which does not allow water or other liquids to pass through. Impervious surfaces greatly increase the volume and velocity of runoff and the amount of pollution and sediment that enters streams and lakes.

Information Repository: A collection of documents about a specific project. Information on certain WQARF and Superfund sites may be available at ADEQ offices and libraries throughout the state.

Indian Country: As defined in U. S. Code Title 18 §1151 , Indian Country includes all land within the limits of any Indian reservation under the jurisdiction of the U. S. government, all dependent Indian communities within the borders of the U. S., and all Indian allotments to which the Indian titles have not been extinguished. The Arizona Department of Environmental Quality does not have discharge permitting authority in Indian Country, even on private fee lands. Operators in Indian Country must pursue permitting through U.S. EPA Region 9 or federally recognized tribes granted “treatment as state” status or primacy by U.S. EPA over specific environmental programs.

Hydrology: TThe study of the movement, distribution, and quality of water throughout the earth.

Hydrogeology: TThe part of hydrology that deals with the distribution and movement of groundwater in the soil and rocks of the earth’s crust, most commonly in aquifers.

Hydraulics: TThe study of the behavior of fluids, static (not moving) and dynamic (moving).

Human Health Risk Assessment: An evaluation of available data on existing or potential risks to human health posed by a contaminated site.

Household Hazardous Waste (HHW): Hazardous products used and disposed of by residential consumers. Those products include paints, stains, varnishes, solvents, pesticides, and other materials or products containing volatile chemicals that can catch fire, react or explode, or that are corrosive or toxic.

Holding Pond: A pond or reservoir, usually made of earth, built to store polluted runoff.

High Pollution Advistory (HPA): Issued when air pollution levels are reaching unhealthy levels for everyone, not just people with respiratory problems. HPAs encourage people to limit outdoor activity and reduce driving and other activities that cause air pollution.

Heavy Metals: Refers to a group of toxic metals including arsenic, chromium, copper, lead, mercury, silver, and zinc. Heavy metals often are present at industrial sites where operations have included battery recycling and metal plating.

Heat Island Effect: A “dome” of elevated temperatures over an urban area caused by structural and pavement heat fluxes, and pollutant emissions.

Health Based Guidance Level (HBGL): Represents  human ingestion (drinking) levels that are unlikely to result in adverse health effects during long-term exposure. The HBGLs are recommended maximum levels and not legally enforceable. However, the HBGLs can be referred to when there are no regulatory levels specified by law or regulation

Hazardous Waste Operator Certification: The training process to meet guidelines produced and maintained by the Occupations Safety and Health Administration that regulates hazardous waste operations and emergency services.

Hazardous Substance: Any material that, because of its quantity, concentration, and physical or chemical characteristics, poses a significant present or potential hazard to human health and safety or to the environment.

Hazardous Air Pollutants (HAPs): Air pollutants which are not covered by ambient air quality standards but which, as defined in the Clean Air Act, may present a threat of adverse human health effects or adverse environmental effects. Such pollutants include asbestos, beryllium, mercury, benzene, coke oven emissions, radionuclides, and vinyl chloride.

Groundwater Model: Refers to computer models of groundwater flow systems that are used by hydrogeologists to simulate and predict aquifer conditions. Models can be used to help summarize, interpret, and present available data; to evaluate such things as monitoring networks or alternate remedial measures; to compare and assess different hypothetical groundwater flow conditions; and to help with water management problems such as predicting changes to the water table due to human activities.

Groundwater Basin: A groundwater reservoir defined by an overlaying land surface and the underlying aquifers that contain the stored groundwater. In some cases, the boundaries of successively deeper aquifers may differ and make it difficult to define the limits of the basin.

Groundwater: Water located beneath the ground surface in soil pore spaces and in the fractures of geologic formations. A formation of rock or soil is called an aquifer when it can yield a usable quantity of water.

Greenwashing: A form of corporate misrepresentation where a company will present a green public image and publicize green initiatives that are false or misleading.

Greenhouse Gas (GHG): Any gas that absorbs infrared radiation in the atmosphere. Greenhouse gases include water vapor, carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), ozone (O3 ), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulfur hexafluoride (SF6).

Green cleaning: Refers to the use of cleaning methods and products with environmentally friendly ingredients designed to preserve human health and environmental quality. Green cleaning techniques and products avoid the use of chemically reactive and toxic products which contain various toxic chemicals.

Gray Water: Wastewater generated from kitchen sinks, washing machines, wash-hand basins, showers and baths, which can be recycled for landscape irrigation and constructed wetlands

Granular Activated Carbon (GAC): An effective absorbent primarily due to its extensive porosity and very large available surface area. By definition, granular activated carbon (as opposed to powdered activated carbon) is composed of particles with sizes greater than 0.8 mm, about the size of coarse sand. Activated carbon is manufactured from a variety of raw materials, including wood, coal, and coconut shells, making it plentiful, relatively inexpensive, and versatile.

Good Neighbor Environmental Board (GNEB): Independent federal advisory committee with mission to advise U.S. government on good neighbor practices along the border with Mexico. Its recommendations are focused on environmental infrastructure needs within the U.S. states contiguous to Mexico.

Global Positioning System (GPS): A space-based satellite navigation system that provides location and time information in all weather conditions, anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites.

Geologic Formation: A body of rock strata (layers) that consists of a certain type or combination of types of rock with the same characteristics such as grain size, or mineral content, or mode of deposition. A formation is usually visually distinguishable from the rock above and below.

Geographical Information System (GIS): A system designed to capture, store, manipulate, analyze, manage, and present all types of spatial or geographical data.

Generator: Any person who produces hazardous waste or causes a hazardous waste to become subject to regulation.

Full-Body Contact (FBC): The use of a surface water for swimming or other recreational activity that causes the human body to come into direct contact with the water to the point of complete submergence. The activity is such that ingestion of the water is likely and sensitive body organs, such as the eyes, ears, or nose, may be exposed to direct contact with the water.

Fugitive Emissions: Emissions not caught by a capture system.

Friable Asbestos Material (FAM): Any material that is more than one percent asbestos and that can be crumbled or reduced to powder by hand pressure.

Fractures: Cracks, faults, or breaks that occur in rock material.

Floodwater: The water that overflows because of a flood.

Fly Ash: Non-combustible residual particles expelled by flue gas..

Floodplain: The flat or nearly flat land along a river or stream or in a tidal area that is covered by water during a flood.

Five-Year Review: A periodic review of a Superfund/WQARF site conducted after a response action has been initiated; the purpose of a five-year review is to evaluate whether the response action remains protective of public health and the environment.

Fissure: A narrow crack or cleft, as in a rock face.

Fissure: A narrow crack or cleft, as in a rock face.

Fish Consumption: The use of a surface water by humans for harvesting aquatic organisms for consumption. Harvestable aquatic organisms include fish, clams, turtles, crayfish, and frogs

Filtration: A treatment process, under the control of qualified operators, for removing solid (particulate) matter from water by means of porous media such as sand or a man-made filter. Filtration also is often used to remove particles that contain pathogens.

Ferrous Metals: Magnetic metals derived from iron or steel. The products made from ferrous metals include appliances, furniture, containers, and packaging like steel drums and barrels. Recycled products include processing tin/steel cans, strapping, and metals from appliances into new products.

Federal Register (FR) : Official journal of the federal government that contains government agency rules, proposed rules and public notices.

Federal Implementation Plan: A federally implemented plan to achieve attainment of air quality standards, used when a state is unable to develop an adequate plan.

Feasibility Study (FS): A process to identify a reference remedy and alternative remedies that appear to be capable of achieving the remedial objectives for the site. It is often done as part of a two-phase investigation in conjunction with a remedial investigation (RI/FS).

Facility: Usually includes a place, site, or area where a hazardous substance has been deposited, stored, disposed of, placed, or otherwise came to be located.

Extraction Well: A well specifically designed to withdraw groundwater or soil vapor for treatment.

Extinction (of light): The loss of light due to scattering and absorption as it passes through the atmosphere.

Exposure Pathway: The route of contaminants from the source of contamination to potential contact with a medium (air, soil, surface water, or groundwater) that represents a potential threat to human health or the environment. Determining whether exposure pathways exist is an essential step in conducting a risk assessment.

Explanation of Significant Differences (ESD): A document issued by the EPA after adoption of the record of decision which explains differences in the remedial action that significantly change but do not fundamentally alter the remedy selected in the ROD with respect to scope, performance or cost.

Exceedance (of pollution standard): Violation of the pollutant levels permitted by environmental protection standards.

Evaporation Ponds: Areas where sewage sludge is dumped and dried.

Ephemeral Water: A surface water that has a channel that is at all times above the water table and flows only in direct response to precipitation.

Environmental Sustainability: Maintenance of ecosystem components and functions for future generations.

Environmental Protection Agency (EPA): Agency of the federal government created in 1970 for the purpose of protecting human health and the environment by writing and enforcing regulations based on laws passed by Congress.

Environmental Management System (EMS): Management of an organization’s environmental programs in a comprehensive, systematic, planned and documented manner and maintaining policy for environmental protection.

Environmental Justice (EJ): 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.

Environmental Impact Statement (EIS): A document required of federal agencies by the National Environmental Policy Act for major projects or legislative proposals significantly affecting the environment. A tool for decision making, it describes the positive and negative effects of the undertaking and cites alternative actions.

Environmental Council of the States (ECOS): National non-profit, non-partisan association of state and territorial environmental agency leaders. The purpose of ECOS is to improve the capability of state environmental agencies and their leaders to protect and improve human health and the environment.

Environmental Assessment (EA): An environmental analysis prepared pursuant to the National Environmental Policy Act to determine whether a federal action would significantly affect the environment and thus require a more detailed environmental impact statement.

Emission: Pollution discharged into the atmosphere from smokestacks, other vents, and surface areas of commercial or industrial facilities; from residential chimneys; and from motor vehicle, locomotive, or aircraft exhausts.

Emergency Response: A remedial action taken in response to a situation that might cause serious harm to people or the environment if not addressed immediately. An example is removal of soil contaminated by lead in a residential area.

Electronic Waste (e-waste): Electronic products nearing the end of their useful life. Computers, televisions, VCRs, stereos, copiers, and fax machines are common electronic products. Many of these products can be reused, refurbished, or recycled.

Electric arc shaft furnace: A cylindrical furnace lined with material capable of enduring high temperatures that produces molten steel by heating iron and steel scrap and other materials that are used as charge materials, using discharges of electricity from carbon-based conductors and direct-current electrical energy. This energy-efficient technology recovers the heat from the furnace off-gas by exhausting it through a shaft where the steel scrap is held prior to charging.

Effluent-Dependent Water (EDW): A surface water that consists of a point source discharge of wastewater. Without the point source discharge of wastewater, it would be an ephemeral water.

Effluent: Treated or untreated wastewater that flows out of a treatment plant, sewer, or industrial outfall. Generally refers to wastes discharged into surface waters.

Ecosystem: The interacting system of a biological community and its non-living environmental surroundings.

Early Response Action (ERA): Refers to a remedial action performed prior to the final remedy, and often prior to the remedial investigation. An ERA addresses current risks to public health, welfare, and the environment; protects or provides a supply of water; addresses sources of contamination; or controls or contains contamination where such actions are expected to reduce the scope or cost of the remedy needed at the site. It is also referred to as an interim remedial action.

Dust Control Action Forecast: An Arizona Department of Environmental Quality forecast which assesses the risk of exceeding the PM-10 federal health standard in Maricopa and Pinal counties.

Drywell: A bored, drilled, or driven shaft or hole, the depth of which is greater than its width, and which disposes of unwanted water, most commonly stormwater runoff, by dissipating it into the ground, where it infiltrates to groundwater.

Dross: A mass of solid impurities that is considered a waste product from molten metal.

Drinking Water: Water safe enough to be consumed by humans or used with low risk of immediate or long-term harm. Also known as potable water.

Drawdown: The vertical distance the groundwater level is lowered due to the removal of water from an aquifer.

Drain Water: Water that enters a drain or channel.

Downgradient: The direction that groundwater flows, similar to “downstream” for rivers. The direction of groundwater flow does not necessarily reflect the topography of the surface.

Domestic Water Source (DWS): The use of a surface water as a source of potable water.

Diurnal Winds: Local winds recurring on a daily basis along the axis of a valley, blowing upslope by day and downslope by night. They occur mostly in calm, clear weather.

Dissolved Oxygen (DO): The oxygen freely available in water, vital to fish and other aquatic life and for the prevention of odors. DO levels are considered a most important indicator of a water body’s ability to support desirable aquatic life.

Dispersion: Dilution over time of a pollutant concentration from its point source due to spreading out of the pollutant.

Disinfectant: A chemical or physical process that kills pathogenic organisms in water, air, or on surfaces. Chlorine is often used to disinfect effluent, water supplies, wells, and swimming pools.

Digester: In wastewater treatment, a closed tank; in solid-waste conversion, a unit in which bacterial action is induced and accelerated to break down organic matter and establish carbon to nitrogen ratio.

Dichloroethylene (DCE): Used to make certain plastics, packaging materials, and flame retardant coatings. Typically, it is a degradation product of other chlorinated solvents.

Dichloro-Diphenyl-Trichloroethane (DDT): The first chlorinated hydrocarbon insecticide chemical name. It has a half-life of 15 years and can collect in fatty tissues of certain animals. EPA banned registration and interstate sale of DDT for virtually all but emergency uses in 1972.

Desalinization: Removal of salt from saline water to provide fresh water (also desalination).

Delegation Agreement (DA): An agreement between ADEQ and a political subdivision that authorizes the political subdivision to exercise functions , powers or duties conferred on the delegating agency by a provision of law.

Declaration of Environmental Use Restriction (DEUR): A restrictive covenant that runs with and burdens the land and requires maintenance of any institutional or engineering control. It must be approved and signed by ADEQ before it may be recorded with the county recorder’s office.

Cubic Feet Per Second (CFS): The flow rate or discharge equal to one cubic foot of water per second or about 7.5 gallons per second commonly used to indicate the rate of flow of a creek, river or flood, i.e., the volume of water that passes a given point in a given amount of time.

Crumb Rubber: Ground rubber fragments the size of sand or silt used in rubber or plastic products, or processed further into reclaimed rubber or asphalt products.

Criteria Flow Condition: The lowest flow over seven consecutive days that has a probability of occurring once in 10 years.

Criteria Air Pollutant (CAP): The 1970 amendments to the Clean Air Act required EPA to set National Ambient Air Quality Standards for pollutants hazardous to human health — ozone, carbon monoxide, total suspended particulates, sulfur dioxide, lead and nitrogen oxide. The term “criteria pollutants” derives from the requirement that EPA must describe the characteristics and potential health and welfare effects of these pollutants. It is on the basis of these criteria that standards are set or revised

Criteria (for Water): Elements of water quality standards that are expressed as pollutant concentrations, levels, or narrative statements representing water quality that supports a designated use.