AUSTIN- Texas Railroad Commissioners this week adopted a new, comprehensive pipeline safety rule that will require all Texas natural gas distribution companies to survey their pipeline distribution systems for the greatest potential threats for failure and make replacements.
The rule, which becomes effective March 14, requires gas distribution operators, such as Atmos, Centerpoint, Texas Gas Service, and City Public Service of San Antonio, to develop risk-based programs to determine the risks in their pipeline systems and then develop a prioritized schedule for replacement of a service line or other facility, such as a main or valve. The risk analysis for distribution pipelines will include pipe location including proximity to buildings or large populations; composition and nature of the piping system, including pipe age, materials, operating pressures and leak history; corrosion history; environmental factors that affect gas migration, such as extreme weather conditions, soil conditions and extensive growth of tree roots around pipelines; and any other conditions known to operators that have a potential to cause a gas leak or allow gas to migrate to an area where it could result in a hazard.
The rule also requires that all joints on steel and plastic pipe below ground must be welded or designed and installed to resist pullout.
Additionally, if steel service lines are determined to be the greatest risk in a distribution system, an operator must implement a replacement schedule for these lines. The rule’s steel service line replacement schedule is as follows:
- A segment with an annualized steel service line leak rate of 7.5 percent or greater is a Priority 1 segment, and an operator must complete all steel service line removal and replacement by June 30, 2013.
- A segment with an annualized steel service line leak rate of between 5 percent and less than 7.5 percent is a Priority 2 segment and an operator must remove or replace no less than 10 percent of the system’s original steel service lines per year.
- A segment with an annualized steel service line leak rate of less than 5 percent is a Priority 3 segment, and those lines must be removed and replaced upon discovery of a leak on a Priority 3 pipeline segment.
Unless otherwise approved in an operator’s risk-based plan, all replacement programs require a minimum annual replacement of 5 percent of pipelines or facilities posing the greatest risks identified.
Texas’ rule is more stringent than the federal government’s recently enacted Gas Distribution Integrity Management rule (49 CFR Subpart P) because it mandates the replacement of pipelines or facilities that pose the greatest potential threats for failure.
Chairman Elizabeth Ames Jones said, “With this rule, the Railroad Commission continues to enhance pipeline safety in Texas, and our agency remains a leading and renowned pipeline regulator in the nation.”
Commissioner Michael L. Williams said, "I initiated this rule last year to improve the overall operations, maintenance, repair and replacement of our state's natural gas distribution companies."”
Commissioner David Porter said, “This latest rule is part of the Commission’s ongoing effort to set the bar high on Texas’ pipeline safety standards and expand upon Commission’s pipeline safety rules implemented in recent years, including the pipeline integrity rule and risk-based leak survey rule.”
Texas was one of the first states in the nation to require a pipeline integrity management program, which became effective April 30, 2001—prior to the issuance of the federal pipeline integrity rule, which was effective Dec. 15, 2003. This pipeline integrity management program requires natural gas transmission and hazardous liquid transmission pipeline operators to verify the integrity of their pipelines by either hydrostatic testing (filling the pipeline with water and pressuring it up to see if there are leaks) or the use of inline inspection tools, such as smart pigs (a device that is run through the pipeline to detect anomalies). The integrity management regulations required that gas companies must have had surveyed half of their systems by Dec. 17, 2007. Surveys of the remainder of their systems have to be completed by Dec. 17, 2012. The federal program requires integrity testing only in high consequence areas (HCAs, ie. densely populated areas) whereas Texas’ pipeline safety rules require the entire regulated line to undergo integrity assessment, which is above and beyond federal rules.
Also, in January 2009,Railroad Commissioners adopted rules (effective February 2009) that required natural gas distribution pipeline operators to submit online to the Railroad Commission all leak repairs on their pipeline systems every six months beginning in July 2009. The reports must list leaks identified and the number of un-repaired leaks remaining on pipelines.
For the latest pipeline safety rule adopted Tuesday by Commissioners, operators must submit to the Commission’s Pipeline Safety Division their written procedures for implementing the new Distribution Facilities Replacement rule requirements by Aug. 1, 2011. Click here for the Commission’s new Distribution Facilities Replacement Rule/