3DSS	three-dimensional seismic survey
Abandonment	In some cases, facilities may be abandoned, such as when pipelines get old and the facilities need upgrading or need to be removed and replaced with a new pipeline. Natural gas pipeline companies must get Commission approval before abandoning facilities or discontinuing services that are subject to FERC jurisdiction.
Abandonment	Converting a drilled well to a condition that can be left indefinitely without further attention and without damaging fresh water supplies or potential petroleum reservoirs
Absorption	Any process that causes one substance to penetrate the inside of another substance. In the case of oil spill clean-up, oil is drawn into porous sorbent materials.
Adsorption	The process that causes one substance to be attracted to and stick to the surface of another substance, without actually penetrating its surface.
Alkylation	Refining process for converting light, gaseous olefins into high-octane gasoline components (reverse of cracking).
Aromatics	Class of hydrocarbons that have at least one benzene ring as part of their structure. Generally describes benzene and benzene derivatives.
Associated Gas	Natural gas associated with oil accumulations, either dissolved in oil or found as a cap of free gas above oil in reservoir.
bbl	barrel
bcf	billion cubic feet
bcpd	barrels of condensate per day
Benzene	An aromatic hydrocarbon present to a minor degree in most crude oils. (Products manufactured from benzene include styrene, phenol, nylon and synthetic detergents.)
Bilge Washing	After oil is removed, a ship's tanks are cleaned. This process is known as bilge washing. It used to be common to clean the tanks using jets spraying seawater. The jets washed the oil residue from the tanks, resulting in a mixture of oil and water that collected at the bottom of the tank, and was then pumped overboard. In some cases, the mixture of oil and water was stored in tanks and re-used as the cleaning solution. Current practice is to use crude oil as the cleaning solution to remove the oil residue from the tank walls. The oil residue and the cleaning solution are then transferred to the load being delivered.
Bio-degradation	The natural process of decomposition by bacteria and other living organisms.
Bio-remediation	The process of accelerating the rate of natural bio-degradation of hydrocarbons by adding fertilizer to provide nitrogen and phosphorus. Following a spill, there are too few of these chemicals compared with the amount of hydrocarbons.
Bitumen	Petroleum in semi-solid or solid forms
boe	barrels of oil equivalent (1 boe = 10mcf)
boe/d	barrels of oil equivalent per day
bopd	barrels of oil per day
BTU	A British Thermal Unit (BTU) is a measure of the heating value of a fuel. It is the amount of heat energy required to raise the temperature of one pound of water one degree Fahrenheit.
Butane (C4H10)	Either of two saturated hydrocarbons, or alkanes, with chemical formula. In both compounds carbon atoms are joined in an open chain.
Carbon	Atomic number is 6; element is in group 14 (or IVa) of periodic table. Carbon content of a hydrocarbon determines, to a degree, hydrocarbon's burning characteristics and qualities.
Carbon Dioxide (CO2)	Colourless, odourless, and slightly acid-tasting gas, sometimes-called carbonic acid gas, molecule of which consists of one atom of carbon joined to two atoms of oxygen. Carbon dioxide in atmosphere tends to prevent escape of outgoing long-wave radiation from Earth to outer space; as more heat is produced and less escapes, temperature of Earth increases. Most important man-made greenhouse gas in UK accounting for 81% of direct global warming potential from national greenhouse emissions in 1990.
Carbon Monoxide (CO)	Chemical compound of carbon and oxygen.
Centrifugal pump	A rotating pump, commonly used for large-volume oil and natural gas pipelines, that takes in fluids near the centre and accelerates them as they move to the outlet on the outer rim.
Certificate of Public Convenience and Necessity	A certificate issued by FERC that allows the recipient to engage in the transportation and/or sale for resale of natural gas in interstate commerce or to acquire and operate facilities needed to accomplish this.
Chlorofluorocarbon (CFC)	Synthetic chemical that is odourless, non-toxic, non-flammable, and chemically inert. Released into atmosphere, chlorine-containing chemicals rise and are broken down by sunlight, whereupon chlorine reacts with and destroys ozone molecules.
Coal	During Carboniferous period much of world was covered with vegetation growing in swamps. This vegetation died and became submerged under water. As decomposition took place, vegetable matter lost oxygen and hydrogen atoms, leaving a peat deposit with a high percentage of carbon. As time passed, layers of sand and mud settled from water over some of peat deposits. Pressure of these overlying layers, as well as movements of earth's crust and sometimes volcanic heat, acted to compress and harden deposits, thus producing coal.
Cogenerator	A generating facility that produces electricity and another form of useful thermal energy (such as heat or steam), that is used for industrial, commercial, heating, or cooling purposes.
Compressor Station	A facility that is used to compress natural gas in order to create additional pressure to increase the amount of gas a pipeline can hold, help move it through a pipeline, or to move it into or from storage.
Condensate	Liquid mixture of pentane and higher hydrocarbons.
Conventional crude oil	Petroleum found in liquid form, flowing naturally or capable of being pumped without further processing or dilution
Cost-Based Rates	A ratemaking concept used for the design and development of rate schedules to ensure that the filed rate schedules recover only the cost of providing the service.
Critical Energy Infrastructure Information (CEII)	CEII is information concerning proposed or existing critical infrastructure (physical or virtual) that: Relates to the production, generation, transmission or distribution of energy; Could be useful to a person planning an attack on critical infrastructure; Is exempt from mandatory disclosure under the Freedom of Information Act; and Gives strategic information beyond the location of the critical infrastructure.
Cumulative production	Production of oil or gas to date
Decompose	To break up into component parts or elements.
Density	The gravity of crude oil, indicating the proportion of large, carbon-rich molecules, generally measured in kilograms per cubic metre or degrees on the American Petroleum Institute (API) gravity scale
Dike	A raised bank constructed to prevent flooding.
Discovery well	An exploratory well that encounters a previously untapped oil or gas deposit
Dismissal	The Commission can dismiss a proceeding or issue a partial dismissal through a Commission order. If a proceeding is dismissed without prejudice, the applicant may make a revised filing for the case. If the proceeding is dismissed with prejudice, the applicant must file a request for rehearing.
Distribution	For natural gas - the act of distributing gas from the city gate or plant to the customer. For electric - the act of distributing electric power using low voltage transmission lines that deliver power to retail customers.
Docket	A formal proceeding before the Commission. Docket numbers are assigned to individual proceedings.
Downstream sector	The oil and natural gas industry has two main components, the upstream producing sector and the downstream refining and marketing sector. The downstream refining and marketing sector consists of pipeline systems, refineries, gas distribution utilities, oil product wholesalers, service stations and petrochemical companies.
Drilling Mud / Fluid	Mixture of base substance and additives used to lubricate drill bit and to counter act natural pressure in formation. Drilling mud provides circulation, flushing rock cuttings from bottom of well bore to surface.
Drilling Mud Nomenclature	Oil Based Mud (OBM), Pseudo Oil Based Mud (POBM), Water Based Mud (WBM).
Dry gas	Or Lean gas is natural gas composed mainly of methane.
Effective Date	The date on which a rate schedule or tariff sheet becomes legally effective.
Electric Utilities	All enterprises engaged in the production and/or distribution of electricity for use by the public, including investor-owned electric utility companies; cooperatively-owned electric utilities; government-owned electric utilities (municipal systems, federal agencies, state projects, and public power districts).
Eminent Domain	Congress has established that natural gas certificates and hydropower licenses issued by FERC also convey the power of eminent domain. Eminent domain is used as a last resort if a landowner and the project proponent cannot reach agreement on compensation for use or purchase of property required for the project. The project proponent is still required to compensate the landowner for the use or purchase of the property, and for any damages incurred during construction. However, the level of compensation would be determined by a court according to state law.
Environmental Assessment	An Environmental Assessment (EA) evaluates the consequences of a proposed action on the environment and recommends measures to minimize any potentially adverse affects. An EA is prepared when the environmental scoping process has determined that the project would not significantly affect the quality of the human environment.
Environmental Impact Statement	The statement required of federal agencies by Section 102 (C) of the National Environmental Policy Act of 1969, for major Federal actions that may significantly affect the quality of the human environment.
Established reserves	That portion of the discovered resource base that is estimated to be recoverable using known technology under present and anticipated economic conditions. Includes proved plus a portion of probable (usually 50%)
Esters	Compounds formed by combination of acids and alcohols.
Ethanol	Chemical formed by fermentation or synthesis.
Ethene	Or Ethylene simplest member of class of aliphatic organic compounds called alkenes, which contain at least one carbon-carbon double bond. Ethylene is a colourless, slightly sweet-smelling gas of formula H2C=CH2. It is slightly soluble in water and is produced in commercial amounts by cracking and fractional distillation of petroleum and from natural gas.
Evaluative Resolution	Someone is determining who is right or wrong during dispute resolution.
Exploratory well	A well into an area where petroleum has not been previously found or one targeted for formations above or below known reservoirs
Federal Rates	Rates that apply to the marketing of wholesale power and transmission services provided by government owned or leased facilities to non-Federal customers. This is done through FERC-approved rate schedules or contracts at revenue levels sufficient to repay the Federal charges incurred in providing these services.
Field	The surface area above one or more underground petroleum pools sharing the same or related infrastructure
Flow line	Pipe, through which oil or gas travels from the well to a processing facility
Gasification	A process that converts liquefied natural gas (LNG) from a liquid back to a gas. This is done by increasing the temperature and decreasing the pressure of the LNG.
Gasoline	Mixture of lighter liquid hydrocarbons used chiefly as a fuel for internal-combustion engines. Produced by fractional distillation of petroleum; by condensation or adsorption from natural gas; by thermal or catalytic decomposition of petroleum or its fractions; by hydrogenation of producer gas or coal; or by polymerisation of hydrocarbons of lower molecular weight.
Gathering Line	Pipelines, generally small in diameter, used to transport oil or gas from the well to a processing facility or a mainline pipeline.
Generation	The act of producing electrical energy from other forms of energy (such as thermal, mechanical, chemical or nuclear); also, the amount of electric energy produced, usually expressed in kilowatthours (Kwh) or megawatthours (MWh).
Greenhouse Gases	Gases that alter thermal properties of atmosphere (for example, water vapour, carbon dioxide, methane, nitrous oxide, CFCs, halons and ozone).
Halons	Halogenated carbon compounds used in fire extinguishing equipment and contributing to stratospheric ozone depletion. Being phased out under Montreal Protocol.
Heavy crude oil	Oil with a gravity below 28 degrees API
Heavy oil	Long chains of hydrogen and carbon atoms.
Hexane	Petroleum liquid found in small amounts in condensates.
Hydrocarbons	Family of organic compounds, composed entirely of carbon and hydrogen (for example, coal, crude oil and natural gas).
Hydrogen (H)	Reactive, colourless, odourless, and tasteless gaseous element with atomic number of 1. Element is usually classed in group 1 (or Ia) of periodic table. Lightest of all gases, hydrogen combines with carbon to form a variety of gaseous, liquid and solid hydrocarbons.
Hydrogenation	Reacting coal with hydrogen at high pressures, usually in presence of a catalyst.
Hydropower	Takes the energy of running water and converts it to electricity.
Hydropower Exemption	Small hydropower projects (less than 5 megawatts) that are exempted from the Commission's licensing requirements. Exemptions are granted in perpetuity.
Hydropower License (Major)	A major license issued by the Commission, authorizes the licensee to construct and operate a new project, or continue to operate an existing project, which is capable of generating more than 5 megawatts. The license term is from 30 to 50 years.
Hydropower License (Minor)	A minor license issued by the Commission, authorizes the licensee to construct and operate a new project, operate an existing project, which is capable of generating less than 5 megawatts. The license term is typically 30 years.
Hydropower Re-license	A major or minor license issued by the Commission that authorizes the licensee to receive a new license term for an existing licensed project. The new license term may be from 30 to 50 years.
Independent Power Producer	A corporation, person, agency, authority, or other legal entity or instrumentality that owns or operates facilities for the generation of electricity for use primarily by the public, and that is not an electric utility.
Independent System Operator	An independent, Federally regulated entity established to coordinate regional transmission in a non-discriminatory manner and ensure the safety and reliability of the electric system.
Initial established	Established reserves before production
Injection well	A well used for injecting fluids (air, steam, water, natural gas, gas liquids, surfactants, alkalines, polymers, etc.) into an underground formation for the purpose of increasing recovery efficiency
Interstate	Sales where transportation of natural gas, oil, or electricity crosses state boundaries. Interstate sales are subject to Commission jurisdiction.
Interstate Commerce	An interchange of goods or commodities which involves transportation between states.
Intervenor	An intervenor formally participates in a Commission proceeding by filing a request to intervene. Intervenors are able to file briefs, appear at hearings, and be heard by the courts if they choose to appeal the Commission's final ruling.
Intrastate	Sales where transportation of natural gas, oil, or electricity occurs within a single state, and does not cross state boundaries. Intrastate sales are not subject to Commission jurisdiction.
kms	kilometres
Light crude oil	Liquid petroleum with a gravity of 28 degrees API or higher
Light oil	Shorter chains of hydrogen and carbon atoms.
Limestone and dolomite Calcium	carbonate-rich sedimentary rocks in which oil or gas reservoirs are often found
Liquefied Natural Gas	Reducing the temperature of natural gas to minus 259 degrees at atmospheric pressure, will convert the gas into a liquid. Its volume as a liquid is about 1/600 compared to its volume as a gas.
Liquefied Natural Gas (LNG)	Gas, mainly methane, liquefied under pressure and low temperature.
Liquefied Petroleum Gas (LPG)	Pressure or refrigeration liquefies lighter hydrocarbons, such as propane, butane, pentane, and mixtures of these gases.
LNGs	liquids natural gas liquids
Local Distribution Company	Any firm, other than a natural gas pipeline, engaged in the transportation or local distribution of natural gas and its sale to customers that will consume the gas.
Market Power	The ability of any market trader with a large market share to significantly control or affect price by withholding production from the market, limiting service availability, or reducing purchases.
Material Safety Data Sheet (MSDS)	Issued by manufacturer of chemical substances that sets out hazards likely to be encountered by those who come into contact with substance.
mbbls/d	thousands of barrels per day
MCF	A MCF is equivalent to 1,000 cubic feet (of gas).
mcf	thousand cubic feet
mcf/d	thousand cubic feet per day
Mercaptans	Strong-smelling compounds of carbon, hydrogen and sulphur found in oil and gas. Added to natural gas for safety reasons.
Metering Facility	A facility that measures and registers the amount and direction of natural gas or electricity that flows through the facility.
Methane	The principal constituent of natural gas; the simplest hydrocarbon molecule, containing one carbon atom and four hydrogen atoms
Methane (CH4)	Also marsh gas, gas composed of carbon and hydrogen, first member of paraffin or alkane series of hydrocarbons. Methane contributed 12% (counting both direct and indirect global warming effects) of UK national greenhouse gas emissions in 1990. Oil and gas production accounted for 2% of national emissions in 1990.
Middle distillates	Medium-density refined petroleum products, including kerosene, stove oil, jet fuel and light fuel oil
mm	millions
mmbbls	million barrels
mmboe	million barrels of oil equivalent
MMCF	A MMCF is equivalent to 1,000,000 cubic feet (of gas), or 1,000 Mcf.
mmcf	million cubic feet
mmcf/d	million cubic feet per day
mmstb	millions of stock tank barrels of oil
Mud	Fluid circulated down the drill pipe and up the annulus during drilling to remove cuttings, cool and lubricate the bit, and maintain desired pressure in the well
MW	mega watt
Natural Gas	A naturally occurring combustible mixture of gases recovered from the earth from wells. It is composed predominantly of methane, but contains other light hydrocarbons and impurities.
Natural Gas	Gas, occurring naturally, often found in association with oil.
Natural Gas Liquid (NGL)	Liquid hydrocarbons found in association with natural gas.
Natural gas liquids	Liquids obtained during natural gas production, including ethane, pr