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Board Meeting: Safety Study on Integrity Management of Gas Transmission Pipelines in High Consequence Areas, Acting Chairman Hart's Closing Statement
Christopher A. Hart
NTSB Board Room and Conference Center

​In closing, I want to recognize the NTSB staff for their hard work in bringing this Safety Study to the Board. The report team did an outstanding job under study co-managers Ivan Cheung and Nathan Doble.

More than a decade after PHMSA issued its integrity management rule for gas transmission pipelines, this study examined whether the IM programs required under the rule are adequate in high consequence areas.

The NTSB found that IM program requirements have kept the rate of corrosion failures and material failures in high consequence areas low, but found no evidence that the overall accident rate has declined. Improvements in IM program areas must be sought in order to prevent catastrophic gas transmission pipeline accidents from occurring again.

As we have heard today, this safety study’s conclusions will provide the gas transmission pipeline industry with solutions to safety issues found in the integrity management program. The study draws its lessons from NTSB investigations of gas transmission pipeline accidents as well as from numerous sources of quantitative and qualitative data including valuable insights from stakeholders in the pipeline safety community.

We looked at the current practices in how high consequence areas are identified, how risks are calculated, and how pipeline integrity is assessed.  We learned from operators and inspectors where resources and guidance are needed to make sure the intent of the gas IM rules is fully realized.  We also learned that intrastate pipeline operators were less likely to use in-line inspection, which provides the highest per-mile discovery of anomalies among all integrity assessment methods.

We looked at how the Pipeline and Hazardous Materials Safety Administration could better support state inspectors, and at how the states could support each other through information sharing and coordination. And, we examined technological solutions such as the use of GIS to improve integrity management programs.

We made 28 new recommendations, 22 of which were to the Pipeline and Hazardous Materials Safety Administration. We asked PHMSA to improve its coordination with, and resources for, state inspectors, and that it work with the National Association of Pipeline Safety Representatives to increase state-to-state coordination.

We recommended that PHMSA improve the positional accuracy in its National Pipeline Mapping System, require the identification of high consequence areas in this system, and make this system more consistent with its other databases.

We recommended that PHMSA take steps to develop and disseminate inspection standards and specifications, work to develop geospatial data resources for the identification of high consequence areas, and provide guidance and criteria for threat identification and risk assessment.

And we asked that PHMSA collect additional information on previous assessments of pipeline segments involved in accidents to determine what went wrong, and to disseminate the lessons learned to the pipeline industry and the public.

Other new recommendations to the American Gas Association and the Interstate Natural Gas Association of America focus on better data collection to support probabilistic risk assessment models, and on promoting the increased use of in-line inspection, especially in intrastate pipeline inspections. 

This safety study also helped us view a previous recommendation to PHMSA in light of evolving in-line inspection technology.  We superseded the previous recommendation that called for re-configuration of pipelines to enable in-line inspection with a new recommendation that calls for either re-configuration or adaptive use of new in-line inspection technologies. The new recommendation would consider not only age, but also internal pressure, pipe diameter, and class location, to determine priority.

Finally, we recommended eliminating the use of direct assessment as the sole integrity assessment method.

More effective use of resources for integrity management of our gas transmission pipelines – especially older pipelines – can prevent great human and monetary damages in future accidents. And integrity management, at its heart, is by nature a data-driven effort.

Using the most appropriate inspection methods to get the best data, requiring the reporting of the most important data, performing comprehensive analyses, and sharing resources collaboratively among all stakeholders will be critical to improving the safety of our pipeline infrastructure in the future.

We hope that the study adopted today serves as a valuable guide to such future improvements.

We stand adjourned.