Oil & Gas Manual: Glossary of Terms

As part of our oil and gas manual, we provide this glossary of environmentally related terms.

Acid Deposition: A complex chemical and atmospheric phenomenon that occurs when emissions of sulfur and nitrogen compounds and other substances are transformed by chemical processes in the atmosphere, often far from the original sources, and then deposited on earth in either a wet or dry form. The wet forms, popularly called "acid rain," can fall as rain, snow, or fog. The dry forms are acidic gases or particulates.

Acidic: A pH which can be corrosive; at hazardous waste levels of 2.0 or less.

Activated Carbon: Carbon granules that are very absorbent. They are used in filters to absorb dissolved hydrocarbon materials, ;and sometimes to remove odors.

Acute Toxicity: An immediate or short term toxic affect.

Adhesion: Molecular attraction which holds the surfaces of two substances in contact.

Administrative Order: A legal document signed by EPA directing an individual, business, or other entity to take corrective action or refrain from an activity. It describes the violations and actions to be taken, and can be enforced in court. Such orders may be issued, for example, as a result of an administrative complaint whereby the respondent is ordered to pay a penalty for violations of a statute.

Adsorption: The adhering of contaminants to another substance, but not the chemical combination of them.

Alkaline: A Ph greater than neutral; corrosive at 12.0 or above.

Alluvium: The sediments usually deposited by running water, most frequently at or just below the surface of ground.

Ambient: The surrounding environment, as opposed to the confined environment. Ambient air exposure means the exposure in the outside to some air contaminant, as opposed to a direct exposure by looking into a tank, or within a building.

Analytes: The chemicals for which a sample is analyzed.

Attenuation: The process by which a compound is reduced in concentration over time, through adsorption, degradation, dilution, and/or transformation.

Area Source or Permit: A combination of sources which are permitted under one umbrella permit.

Backfill: The material, usually dirt, used to refill a hole which has been dug.

Background: The concentration of contaminants in an ambient area unaffected by the industrial concern at hand.

Baghouse Filter: Large fabric bag, usually made of glass fibers, used to eliminate intermediate and large (greater than 20 microns in diameter) particles. This device operates in a way similar to the bag of an electric vacuum cleaner, passing the air and smaller particulate matter, while entrapping the larger particulates.

Bailed Sample: A sample collected with a pail or bucket, usually stainless steel, by lowering it into the well.

Bailer: A long cylindrical container with a valve at its lower end used to extract water from a well or test hole (such as a water sample).1

Barite: Barium sulfate, BaSO41 used to increase the weight of drilling mud. It is 4.2 times heavier than water.2

Baseline: An established level of contamination or activity before entering a property or commencing operations. It may be the contamination level, or emission levels.

Bedrock: Solid rock in the ground which usually prevents...