Glossary

Any gas released into the atmosphere for which a federal state or regulation exists. Used interchangeably with the term "air contaminant."

The equivalent amount of CO2 emitted by one metric ton of any greenhouse gas (e.g. 1 metric ton of methane is equivalent to 25 tons of CO2.)

Any equipment used to destroy, eliminate, reduce, or control the emission of air contaminants to the atmosphere.

An air pollutant for which a national ambient air quality standard is set by EPA. There are 6 air pollutants classified by EPA as criteria pollutants They are: carbon monoxide, lead, nitrogen dioxide, ozone, inhalable particulate matter, and sulfur dioxide.

SCF - standard cubic feet

The efficiency with which a control device reduces emissions that would otherwise be vented.

The mass or mass rate of air pollutants/contaminants that enter the atmosphere. Typically, emissions are reduced after gases have passed through an air pollution control device (such as a flare).

An unscheduled maintenance, startup, or shutdown activity or upset or unplanned or unavoidable breakdown or excursion of a process or operation that results in an unauthorized emission.

A flare is an air pollution combustion control device that uses an uncontrolled volume of air to burn gases.

Flaring is the controlled combustion of natural gas for operational, safety, or economic reasons.

A general term for organic materials formed from decayed plants and animals that have been converted to crude oil, coal, natural gas, or heavy oils by exposure to heat and pressure in the earth's crust over hundreds of millions of years.

Any gaseous or particulate contaminant entering the atmosphere that could not reasonably pass through a stack, chimney, vent, or other functionally equivalent opening designed to direct or control its flow.

"The proportion between oil and natural gas obtained from a producing well under given conditions of temperature and pressure. Commonly abbreviated GOR and measured in standard cubic feet of gas per barrel of oil (SCF/BBl) . . ."

A well drilled primarily for the production of natural gas.

Any gas that absorbs infrared radiation in the atmosphere. Greenhouse gases include carbon dioxide, methane, nitrous oxide, ozone, chlorofluorocarbons, hydrochlorofluorocarbons, hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride.

Air pollutants that are known or suspected to cause cancer or other serious health effects, such as reproductive effects or birth defects, or adverse environmental effects. Also referred to as "air toxics" or "toxic" air pollutants. EPA has officially designated 187 air pollutants as "hazardous."

Also known as “fracking,” this is a technique that is used for accessing natural gas and oil in tight geologic formations. The process involves pumping or injecting a combination of water, proppant (e.g. sand), and minor quantities of chemicals at high pressures to fracture rock and release(...)

Chemical compounds containing one or more hydrogen and carbon atoms.

The system of pipelines and processing plants through which natural gas, crude oil, and condensate are transported.

A well that produces less than 20 barrels of oil per day.

MCF - thousand cubic feet

A hydrocarbon consisting of one carbon atom and 4 hydrogen atoms. Methane is also classified as a greenhouse gas.

A term identifying the industries that transport natural gas, crude oils and condensates from wellsites. Alternately, these are known as “gatherers.”

MMBTU - million thermal British units

MSCF - thousand standard cubic feet

A fossil fuel made up of organic material that exists as a gas at atmospheric conditions. Natural Gas is typically composed of hydrocarbons, carbon dioxide, nitrogen, hydrogen sulfide, and trace sources of other organic material.

NGLs are hydrocarbons associated with natural gas and are a by-product of natural gas processing. NGLs include ethane, propane, butane, iso-butane, and natural gasoline. They are sold separately and have a variety of different uses, including enhancing oil recovery in oil wells, providing raw(...)

A mixture of hydrocarbons usually existing in the liquid state in natural underground pools or reservoirs.

Well drilled primarily for the production of oil.

The entity responsible for operating an oil and natural gas well.

Sour - Crude oil or natural gas that contains significant concentrations of hydrogen sulfide.

A well that produces 15 barrels of oil or 90 Mcf of natural gas per day or less.

Sweet - Crude oil and/or natural gas that is not considered sour.

A sudden or unavoidable event beyond the control of the operator that could not have been avoided.

A term identifying the oil and natural gas exploration and production industry. Includes the drilling and hydraulic fracturing processes, as well as storage prior to transfer to a midstream company.

The release of gas into the atmosphere without first passing through an air pollution control device (such as a flare).

Hydrocarbons with 3 or more carbon atoms, including but not limited to, propane, butane, octane, among many others.

The process of installing equipment within a well so that the oil and natural gas can be brought to the surface after drilling operations have concluded. In most cases, this process includes hydraulic fracturing (also called “fracking”), although some do not require it.

Operations to repair or improve performance in a well (i.e. restore production or injection rates, or replace downhole equipment.)

Installed at the surface and is the point at which the oil (and/or natural gas) exits the ground from the wellbore.