Pipeline & Gas Journal
Oildom Publishing Company of Texas, Inc.
1160 Dairy Ashford Road, Suite 610
Houston, TX 77079
Dear Mr. Share:
It is important that we get the facts straight about the San Bruno accident before drawing conclusions about its causes and what they may mean for improving pipeline safety practices, pipeline safety technology and pipeline safety regulation. Consequently, the Interstate Natural Gas Association of America was disappointed with Pipeline & Gas Journal’s assessment that “what we know from published reports indicate that the San Bruno main had a good chance of failing sooner rather than later.” (“Plenty of Questions About San Bruno,” October, 2010). This statement is followed by four points that your publication suggests were indicative of the likelihood that the San Bruno line would fail. We take issue with three of these:
1. “The section of pipe that exploded was 62-years-old.” Absent a host of other factors concerning the age of the pipeline, its surrounding environment, and the history of its inspection and maintenance, there is no basis for concluding that age is indicative of a pipeline’s likelihood of failure.
2. “The main was made of steel, which comprises nearly two thirds of the nation’s larger gas mains.” This is followed by a statement about the Texas Railroad Commission announcing a plan to convert steel gas distribution mains to plastic. The merits of plastic versus steel distribution mains are irrelevant to analysis of the San Bruno accident, which involved a natural gas transmission pipeline, because plastic pipe that might be suitable in a distribution main cannot operate at the higher pressures present in a transmission pipeline.
3. “The age of the gas main, combined with twists and turns of the pipeline, prohibited PG&E from using robots that would have been the best way to maintain and inspect the line.” It is true that inline inspection (ILI) tools – or “smart pigs” – have become increasingly sophisticated and are an invaluable resource in maintaining the integrity of the nation’s natural gas transmission pipelines. But there are limits on the types of anomalies and damages to a pipeline that can be detected using ILI tools. Pipeline & Gas Journal further asks “[e]xactly how safe is the delivery system?” Here is a succinct answer:
Over the past 20 years, all the traditional measures of risk exposure have been rising
– population, energy consumption, pipeline ton-miles. At the same time, the
number of significant incidents involving pipelines has declined 50 percent.
That is not the industry speaking. It is a direct quote from the written testimony of Cynthia L. Quarterman, Administrator of the Pipeline and Hazardous Materials Safety Administration, for a hearing before the U.S. House of Representatives Committee on Energy and Commerce Subcommittee on Energy and the Environment on September 23, 2010.
The San Bruno accident is perplexing because the pipeline had been inspected pursuant to PG&E’s integrity management program and because there is no readily identifiable cause of the failure. INGAA’s members are eager to learn the root cause and stand ready to work with our colleagues in the natural gas industry, industry research organizations, federal and state pipeline safety regulators, the Congress and other stakeholders to examine these findings and determine what actions are necessary to enhance the safety of the nation’s natural gas delivery system.
Pipeline & Gas Journal is correct in its view that the San Bruno accident will be the impetus for what may be an unprecedented review of the fundamental tenets of pipeline safety. It is important that such a review, and what is written about it, be grounded in a thorough understanding of the facts and causes. Unfortunately, the magazine’s observations fall short of this standard.
Donald F. Santa, Jr.
Interstate Natural Gas Association of America