Operating Conference Roundtable Focuses On Integrity Management

The Southern Gas Association (SGA) holds an annual conference at which many subjects are discussed involving gas transmission and distribution operations.

Topics are chosen by the participants and, while some short presentations are provided, most of the time is spent in peer-to-peer discussions of specific, present-day issues of concern to pipeline operators. This article summarizes some of the relevant issues discussed at the July 2008 Transmission Integrity Management Program (TIMP) roundtable held in Atlanta. The TIMP sessions were co-chaired by Garry Matocha, Principal Engineer of Spectra Energy and Virgil Wallace, Senior Pipeline Integrity Engineer of Williams.

The roundtable began with four presentations providing background on successes and effects on operators of the IMP regulations. The presentations also set the stage for subsequent discussions among operators and service providers.

Dave Johnson of Panhandle Energy and chair of the Interstate Natural Gas Association of America (INGAA) Pipeline Safety Committee led off discussing what the industry has learned to date from performing integrity assessments and the PHMSA IMP audits. In high-consequence area (HCAs) - the focus of the regulations - there have been 0.05 immediate repairs per mile and 0.14 scheduled repairs per mile, since inception of the regulations. Immediate response conditions are being conservatively classified. The industry has an effective suite of tools inline inspection (ILI), engineered pressure tests and direct assessment and it has capable service providers to apply them.

There remains a need for new technology. Representatives of the industry, service providers and PHMSA are working to establish additional inspection tools such as Guided Wave Ultrasonic Technology (GWUT). The process for using GWUT is advancing successfully and is now embodied in a document referred to as the “18 Points.” This is a consensus document developed jointly by PHMSA and INGAA. (http://primis.phmsa.dot.gov/gasimp/docs/GuidedWaveCheckList110107.pdf)

Integration of best practices, as well as knowledge advancement and sharing, are effectively taking place. The industry is good at “pigging and digging” but needs to improve in documentation. While there is no uniform understanding of requirements and enforcement among the PHMSA auditors, the inspection teams’ expectations appear to be converging.

Mark Hereth, a principal at P-PIC, told how IMP has changed what operators do. Operators are formalizing processes and procedures as well as improving documentation of their work. While the regulations and even the supporting consensus standards are largely prescriptive, operators have found multiple paths to solve specific issues. More companies are now making long-term plans to assess their entire systems over 10-15 years It is also becoming clear that operators who successfully apply IMP are finding that they attain a competitive advantage which enables them to obtain special permits for class location changes and operation up to 80% of SMYS.

Chris Bullock, senior pipeline integrity engineer with CenterPoint Energy, provided examples of operator experience as what constituted or created a new HCA and why. He also showed how different kinds of corrosion, dents, SCC and weld anomalies have been found as a result of the pipeline assessments.