Gas Well Drilling & Production in Grand PrairieOn September 20, 2005, the City Council adopted the first Gas Drilling and Production Ordinance regulating gas wells within the City limits and its extraterritorial jurisdiction (ETJ). Since then, the City has adopted nine updated gas drilling and production ordinances in an effort to ensure the health and wellbeing of Grand Prairie residents.
The Barnett ShaleGrand Prairie lies atop a natural gas reserve known as the Barnett Shale formation. The Barnett Shale is a natural gas rich geological formation in Texas that spans 5,000 square miles across at least 20 counties. Some experts have suggested the Barnett Shale may be the largest onshore natural gas field in the United States. The field is proven to have 2.5 trillion cubic feet of natural gas, and is widely estimated to contain as much as 40 trillion cubic feet of natural gas resources.
Although the discovery of the Barnett Shale is not new, technology now makes it possible to bring this natural resource to the surface. Historically, gas wells were drilled vertically into formations that had heavy pooling in one area. Now, gas drillers are able to drill horizontally, making 90 degree turns in a few hundred feet. Horizontal drilling allows drillers to capture gas without drilling multiple wells.
Class 1 gas permit means a permit is required if the edge of the pad site boundary for the proposed well is to be located within seven hundred (700) feet of a residence, religious institution, public building, hospital/medical building, nursing home, school or public park, but no closer than five hundred (500) feet. A Class 1 gas permit may require City Council approval.
Class 2 gas permit means a permit is required if the edge of the pad site boundary for the proposed well is to be located greater than seven hundred (700) feet of a residence, religious institution, public building, hospital/medical building, nursing home, school or public park.
Environmental Concerns with Gas Well DrillingGas well operations can have many environmental concerns. Among them are, water consumption, wastewater disposal, use of toxic chemicals, truck traffic, air pollution, noise from the operations, potential groundwater and well water contamination, deforestation, road-building and surface water runoff.
Horizontal drilling reduces the affects to the land surface as fewer wells need to be drilled. In addition, the City requires that applicants use a closed loop system for the spoils of drilling – an oily mud mixture – is used. A closed loop system means that all the “mud” will be stored in tanks rather than on the ground. This system dramatically reduces environmental impacts.
The Gas Well Drilling and Production Ordinance also mandates that the applicant: 1) meet noise level requirements by conducting a Noise Abatement Study prior to the drilling, 2) have secondary containment around all tanks, 3) submit quarterly air monitoring, and 4) clean up all spills immediately.
City Review and Inspections
Prior to permitting a pad site, City Staff from Environmental Services, Legal, Fire, Building Inspections, Transportation, Planning, and Engineering Departments thoroughly review the application submitted by the operator to ensure compliance with local and state regulations. On occasion, an application must go to City Council before being approved.
Once an application is approved and operations have commenced, Environmental Services Staff inspects the pad site quarterly, in response to citizens’ complaints/concerns, and during drilling and completion activities. Environmental Staff also performs air monitoring at each pad site.
In addition, a third party Gas Inspector inspects the site during the initial drilling, fracturing, completion activities, and annually.
All gas wells are permitted by the City of Grand Prairie, Environmental Services Department to ensure that all local, state, and federal regulations are met by the applicant. After a well has been permitted, the site will be prepared by bulldozers and other equipment and a drill rig will be set up. During the drilling operations, expected to last from weeks to several months per well, the drilling crew and security will be on-site 24 hours a day, 7 days a week. The drill rig will be used to drill through solid rock to get to the natural gas reserves about 1.5 miles below the surface.
To improve gas production, a mixture of chemicals, sand and water is forced into the well to fracture the rock and allow natural gas to flow to the well bore. This process, called “fracturing” takes several days per well.
After the well is drilled, storage tanks, meters, pumps, and other equipment are brought onto the site and the area is cleaned up and fenced. These wells are expected to be productive from 30 to 50 years. Occasional “refracturing” may be needed to maintain the flow of gas from the well.
Once the well stops producing, the well is capped and the operator returns the site to its original condition as much as practicable.