Today’s natural gas gathering pipelines are constructed and maintained to ensure their safe transport of gas for decades to come. It is a combination of quality materials, high construction standards, adherence to state and federal regulations and a century of pipeline technology which merge to create confidence in the natural gas pipeline system.
The epoxy-coated, high-grade steel pipe which is the building block of the gathering lines plays an important role in the safety of pipelines. The coating and thick walls of the pipe work to inhibit corrosion and any possibility of a leak. X-ray testing of pipeline welds ensures secure pipe connections and hydrostatic tests make use of water pressure to guarantee that the pipeline string has an airtight seal.
Pipelines are operated under specific federal and state regulations and industry standards intended to ensure public and environmental safety and health. Gathering lines are regulated and controlled by the U.S. Department of Transportation and the Environmental Protection Agency. The Railroad Commission of Texas (RRC) is authorized to enforce federal regulations and to audit pipeline inspections.
Texas Midstream Gas Services (TMGS) designs pipelines to higher standards than are required by the federal government, using a higher class of pipe specification in all new pipeline routes throughout the Barnett Shale. The pressure at which the pipe operates is also an indicator of the safety measures taken when transporting natural gas. As required by law, pipelines are only allowed to operate at pressures far below the actual rated strength of the pipe.
They employ inspectors, who periodically inspect or audit pipeline companies and their facilities for compliance with the regulations.
RRC inspectors typically perform some type of audit annually, or more frequently if necessary, on pipelines which are in service. The auditor may look at documents, records or pipeline sites in the course of these audits and interview responsible personnel.
Position of valve sites is another safety component built into the pipeline infrastructure. Valve sites are needed at specific intervals, as regulated by the federal government, so that the flow of gas may be shut off to a particular area of the pipeline. The ability to isolate part of the route allows for the use of inspection tools to clean and maintain the internal walls of the pipeline. And should the unlikely event of a leak occur, it allows for swift containment of the gas stream.
With a network of 2 million miles of pipeline* operating safely within the U.S., it is clear that this technology has been embraced by generations.
*U.S. Dept. of Transportation, Pipeline and Hazardous Materials Safety Division, July 2008
DIG TESS
Because the number one cause of pipeline incidents is a result of third-party digging*, TMGS actively participates in the Texas Excavation Safety System, otherwise known as DIG TESS. DIG TESS is a one-call system which aims to prevent these types of excavation incidents from occurring. Simply calling the number 811 can help save lives and protect infrastructure.
Any excavator breaking ground to a specified depth of 18 inches or greater — from professionals to do-it-yourself homeowners — is required to call DIG TESS (811) at least 48 hours prior to digging. The system alerts TMGS of the planned excavation, and in some cases TMGS sends a representative to monitor any construction around the pipeline.
Through the DIG TESS system, marked lines will show excavators the approximate location of underground lines and prevent undesired consequences. By calling 811 before starting a digging project, citizens can help keep their community safe.
As a member of DIG TESS, TMGS is involved in public awareness initiatives for pipeline operators and the general public.
*Railroad Commission of Texas, 2006 press release
The pipeline safety regulations require pipeline companies to have public awareness programs to help educate the general public, emergency responders and excavators (those digging around pipelines). Topics may include the safety of pipelines, how to recognize a potential leak or problem, how to notify the company in case of a problem, how to recognize pipeline marking signs, etc. This is accomplished through mailing out brochures, media advertising, participation in public meetings and other means to meet these requirements.