Drilling for Oil

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At a typical drilling site, you will often see barite tanks, compressor stations, water tanks, transport trucks and the drilling rig. A barite tank holds materials used as a weighting agent for drilling fluids in oil and gas exploration to suppress high formation pressures and prevent blowouts. The compressor station is used to compress natural gas to allow it to travel through pipelines. 

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Depending on the configuration of the drilling site, you may see a flare stack, tank batteries, separators and flowlines. A flare stack is used to flare waste or unusable gas. Preferably, this associated gas is reinjected into the reservoir, which saves it for future use while maintaining higher well pressure and crude oil producibility. A tank battery is typically a group of tanks that are connected to receive produced water from a well.



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Any time a well is drilled in Texas including an oil, gas or injection/disposal well, Commission rules require that surface casing in the well be set below the depth of usable quality water to protect the state's water resources. Because usable quality water levels vary throughout the State, the Commission's Groundwater Advisory Unit performs an essential function in determining specific groundwater protection depths for each new well.

The Commission’s rules include strict well construction requirements that require several layers of steel casings and cement to protect groundwater.  

The first protection layer for usable quality groundwater in a well is the surface casing, a steel pipe that is encased in cement that reaches from the ground surface to below the deepest usable quality groundwater level. Surface casing acts as a protective sleeve through which deeper drilling occurs.

The second protection layer for usable quality groundwater is the production casing, a pipe placed in the wellbore to the well’s total depth and permanently cemented in place. Some operators inject fracturing fluid in this casing. Depending on the fracturing pressure needed, other operators use a third protection layer by injecting fracturing fluid in the tubing string that conducts the fracturing fluid to the zone to be perforated and fractured. In addition, Commission rules require gauges that monitor these casings at the surface, so if there is a downhole problem, it is easily and quickly identified. 

Last Updated: 6/9/2016 2:10:54 PM