Casing: Casing refers to the steel pipe used to separate the fluids and gas going up and down a well from drinking water aquifers and geologic areas other than the production zone.
Cementing: This process secures the casing in place to the surrounding rock using cement. The inner layers of casing are secured to the casing of outer layers.
Coupling: A coupling is a short length of pipe used to connect two joints of casing. Couplings are an integral component to maintaining the integrity of the connections between pipes. A casing coupling has internal threads that are machined to match the external threads of the long joints of casing. The two joints of casing are threaded into opposite ends of the casing coupling.
Flowback water: Flowback water is a substance that returns to the surface through the wellbore after hydraulic fracturing is complete.
Formation water: The water naturally present in the production zone that surfaces through the wellbore. When combined with flowback water, the mixture returning to the surface is referred to as produced water.
Frack water: The water that is used to create fracturing fluid. The source could be drinking water, surface water, groundwater, or recycled water.
Fracturing fluid: A combination of water, sand, and chemicals that is injected down the wellbore and into the production zone during hydraulic fracturing to create fractures in the shale rock, which allows oil and natural gas to flow into the wellbore.
Horizontal drilling: An innovative drilling technique that allows for drilling horizontally below the surface, to extend the wellbore into a larger area of the production zone. This technique allows for multiple wells to be drilled from each well pad and allows for oil and gas extraction in areas that were not previously accessible by conventional drilling.
Hydraulic fracturing, aka fracking, or fracing: A well stimulation technique that involves the injection of fracking fluid, under pressure, through the wellbore to create artificial fissures (fractures) that allow oil and natural gas to travel into the wellbore efficiently.
NPDES: This acronym stands for The National Pollutant Discharge Elimination System, which is part of the Clean Water Act. The act regulates discharges of pollutants into surface water bodies and is administered either by USEPA or state agencies.
Produced water: The combination of flowback water and formation water that returns to the surface along with the oil and natural gas during the extraction process. Produced water can be disposed of through underground injection, industrial treatment prior to being returned to a surface water body, or it can be recycled and reused at another fracing operation.
Production: In oilfield drilling operations, production refers to the stage when oil and or natural gas is brought to the surface and captured.
Production zone: The geologic area where oil and natural gases are extracted. Production zones vary in depth, ranging anywhere from several hundred to several thousand feet below the surface, well below drinking water aquifers.
Proppant: Typically composed of sand, proppant is a component of a hydraulic fracturing fluid mixture designed to hold open fractures after the fracturing process has been completed.
UIC: This stands for the Underground Injection Control program, a section of the Safe Drinking Water Act, which regulates, among other types of injection wells, Class II Oil and Gas waste disposal wells.
Wellbore: The hole drilled into the ground for the purposes of oil and gas production. The interior of the wellbore is generally isolated from the surrounding environment through casing and multiple cementing processes. The interior of the wellbore is where fracturing fluids are injected during the fracking process, and through which oil, natural gas, and produced water flow up during production.
Well pad: The well pad refers to the location where a drill rig is built, and from which the drill hole originates.
Well stimulation: Well simulation describes the processes implemented to increase the flow of oil and natural gas coming up the wellbore. Hydraulic fracturing is one example of a well stimulation technique.