A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Abandoned Well: A well whose use has been permanently discontinued or which is in a state of such disrepair that it cannot be used for its intended purpose.

Abatement: Reducing the degree or intensity of, or eliminating, pollution.

Activated Carbon: A highly adsorbent form of carbon used to remove odors and toxic substances from liquid or gaseous emissions.

Aerobic: Life or processes that require, or are not destroyed by, the presence of oxygen. (See: anaerobic.)

Air Monitoring: (See: monitoring.)

Air Phase Unit: Term applied to the air recovery and treatment (via granular activated carbon filter) system, employed by D.L. Services Inc. to remediate of hydrocarbon-impacted air, typically from the interior of residential dwellings.

Air Sparging: Injecting air or oxygen into an aquifer to strip or flush volatile contaminants as air bubbles up through the ground water and is captured by a vapor extraction system.

Air Stripping: A treatment system that removes volatile organic compounds (VOCs) from contaminated ground water or surface water by forcing an airstream through the water and causing the compounds to evaporate.

Aliquot: A measured portion of a sample taken for analysis. One or more aliquots make up a sample. (See: duplicate.)

Ambient Air: Any unconfined portion of the atmosphere: open air, surrounding air.

Anaerobic: A life or process that occurs in, or is not destroyed by, the absence of oxygen.

Annular Space, Annulus: The space between two concentric tubes or casings, or between a well casing and the borehole wall.

Aqueous: Something made up of water.

Aqueous Solubility: The maximum concentration of a chemical that will dissolve in pure water at a reference temperature.

Aquifer: From the Latin for "water carrier", an underground geological formation (typically porous material, such as sand or gravel, or fractured rock) that stores and is capable of transmitting water in sufficient quantities to serve as a source of water supply.

Aquitard: A geological formation that  prevents significant flow of water (e.g. clay).

Aromatics: A type of hydrocarbon, such as benzene or toluene, with a specific type of ring structure. Aromatics are sometimes added to gasoline in order to increase octane. Some aromatics are toxic.

Artesian (Aquifer or Well): Water held under pressure in porous rock or soil confined by impermeable geological formations.

Assessment: An appraisal or evaluation (e.g. assessment of the degree of success of a remediation procedure at a contamination site).

Attenuation: The process by which a compound is reduced in concentration over time, through absorption, adsorption, degradation, dilution, and/or transformation. an also be the decrease with distance of sight caused by attenuation of light by particulate pollution.

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z