Arkansas Department of Environmental Quality (ADEQ) – The agency that oversees the state’s environmental regulatory programs. It is organized into six regulatory divisions focusing on air, hazardous waste, regulated storage tanks, solid waste, mining and water. (www.adeq.state.ar.us)

Arkansas Natural Resources Commission (ANRC) – The state commission that’s charged with managing and protecting water and land resources in Arkansas. It consists of three divisions – conservation, water development and water management. (www.anrc.arkansas.gov)

Arkansas Oil and Gas Commission (AOGC) – The regulatory agency that oversees oil and gas issues within the state. Among other things, the AOGC issues permits for oil and gas operations and holds hearings to enforce statutes and regulations related to the oil and gas industry. (www.aogc.state.ar.us)

Arkoma Basin – A geological region that consists of portions of west central Arkansas and southeastern Oklahoma. It is an area of low-risk drilling operations with stable production and gas reserves.

Bcf – A unit of measurement representing one billion cubic feet, the standard for measuring natural gas volume on a large scale or over an extended time, such as total per-year volume.

British thermal unit (BTU) – The generally accepted unit for measuring heat; the quantity of heat required to raise the temperature of 1 pound of liquid water by 1 degree Fahrenheit at the temperature at which water has its greatest density.

Casing – A steel pipe used to protect both the well and the earth during the drilling and production process. It prevents the wall of the hole from caving in and the movement of fluids from one formation to another, while improving the efficiency of extracting the natural gas from productive wells.

Central Point Facility (CPF) – A station used in the midstream stage of natural gas transport where gas is compressed so it can enter larger transmission lines. CPFs consist of gas treatment facilities that remove impurities from the gas, dehydration facilities that remove water vapor from the gas and prevent corrosion in downstream steel pipelines, and compression facilities that boost the gas pressure from less than 50 psig to more than 1,000 psig.

Christmas tree – The assembly of valves, pipes and fittings that control the flow of oil and gas from a well.

Dehydration facility – The area in the Central Point Facility where water vapor is removed from the gas. The process also prevents corrosion in downstream steel pipelines.

East Texas Basin – A geological region in east Texas that includes several different formations rich in natural gas. Southwestern Energy runs a low-risk drilling program with significant potential for production and reserve growth in the Overton Field area and in the Angelina River Trend area.

Environmental Protection Agency – The federal agency created in 1970 to “permit coordinated and effective governmental action on behalf of the environment.” It is designed as the “public’s advocate for a livable environment .” (www.epa.gov)

Fayetteville Shale – An unconventional gas reservoir on the Arkansas side of the Arkoma Basin. Ranging in thickness from 50 to 550 feet and in depth from 1,500 to 6,500 feet, the Mississippian-age shale is the geologic equivalent of the Caney Shale found on the Oklahoma side of the Arkoma Basin and the Barnett Shale found in north Texas. (See “Shale”)

Federal Energy Regulatory Commission (FERC) – A 5-member regulatory commission within the Department of Energy that regulates natural gas and hydropower projects, and the transportation and sale of natural gas, oil and electricity in interstate commerce. (www.ferc.gov)

Field – An area consisting of a single reservoir or multiple reservoirs on or related to the same geological structure. While the field name usually refers to the surface area, it may also refer to the underground formations.

Gathering lines – The pipes that transport natural gas from individual wellheads to Central Point Facilities (CPFs).

Horizontal and slant drilling – Drilling techniques that allow for maneuvering through underground formations to reach gas deposits even when the wellhead can’t be sited directly over them.

Hydraulic fracture stimulation – The use of hydraulic pressure to create microfractures through which oil or gas move to reach the well.

Hydrocarbons – The class of chemicals made up of carbon and hydrogen molecules; includes oil and natural gas.

Interstate transmission lines –The pipelines used to move purified natural gas from midstream facilities to the market for distribution to end users.

Lease – A legal contract specifying the relationship between an energy company and a landowner or mineral rights holder on a particular tract.

Midstream – The second of three stages in the delivery of natural gas to market, midstream generally refers to all the steps that occur between production at the well site and the point of sale at market. It includes the process of gathering, treating and transporting natural gas to the point of sale. Southwestern Energy created two companies that specialize in midstream activities – DeSoto Gathering Company, LLC (DGC) and Southwestern Energy Services Company (SES).

Mercaptan – The foul-smelling additive that gives natural gas its distinctive odor. In its unrefined state, natural gas is odorless. The addition of Mercaptan is a safety precaution.

Mcf – A unit of measurement representing one thousand cubic feet of natural gas.

MMcf – A unit of measurement representing one million cubic feet of natural gas; the standard for measuring a natural gas well’s output, typically by per-day volume.

Play – A description for the portion of the exploration and production cycle following the identification by geologists and geophysicists of areas with potential oil and gas reserves.

PSIG –A measure of the amount of pressure in a gas line in pounds (of pressure) per square inch in relation to the surrounding atmosphere.

Royalties – The owner's share of the value of minerals (oil and gas) produced on the property, free of the costs of production.

Seismic imaging – The technology-based process that helps determine where to drill for natural gas by using sound waves and powerful computers and processors to create three-dimensional maps of rock formations thousands of feet under ground. The process is much like that of a sonogram or an MRI, which is commonly used to create visual images of the inside of the human body. Small, specialized rigs drill holes approximately 20 to 40 feet deep and create vibrations while small listening devices called geophones record the sound waves. When charges are triggered by a radio signal, a mobile, truck-mounted central recording unit collects the sound readings from all the geophones. Highly specialized computer software processes the data and generates images for geophysicists.

Shale – A tightly-packed, fine-grained sedimentary rock composed of layers of compressed clay, silt or mud.

Southwestern Energy’s Formula – A formula that represents the mission of Southwestern Energy. It stands for: “The Right People doing the Right Things, wisely investing the cash flow from our underlying Assets, will create Value Plus.”

Tcf – A unit of measurement representing one trillion cubic feet of natural gas, typically used in expressing an entire region’s reserves or long-term production of natural gas.

Unconventional – An oil or gas resource in which the targeted reservoirs generally fall into one of three categories: 1) tight sands; 2) coal beds; and 3) shales. The reservoirs tend to cover large areas and lack the readily apparent traps, seals and discrete hydrocarbon-water boundaries that typically define conventional reservoirs. These reservoirs generally require stimulation treatments or other special recovery processes in order to produce economic flow rates.

Wellhead – The assemblage of equipment installed at the opening of a gas well to regulate and monitor the extraction of natural gas, prevent leakage and prevent blowouts from high gas pressure.