A federal investigative hearing on the deadly Sept. 9, 2010 San Bruno explosion triggered by the rupture of a high-pressure Pacific Gas & Electric Co. pipeline was all about getting answers — but it has also sparked new questions.
For instance, why didn't the San Bruno Fire Department have maps of the 30-inch gas line running beneath the neighborhood where the blast destroyed 37 homes and killed eight people? Why did PG&E's records list that section of pipe as seamless when the federal investigation revealed that it actually consisted of shorter pieces of pipe, called pups, welded together? Why has PG&E been unable to produce records of close to 30 percent of its pipeline infrastructure, proving that the lines are in decent shape? And does the paperwork it has produced contain reliable information?
These shortcomings speak to a broader issue gaining attention as more fatal pipeline ruptures grab headlines. On a national scale, at least 59 percent of onshore gas transmission pipelines were installed before 1970, according to a report issued by the U.S. Department of Transportation's Office of Pipeline Safety, making most of the infrastructure a minimum of four decades old.
Pipelines everywhere are getting older, and in some cases, weaker. Yet there tends to be a lack of awareness about the risks associated with the subsurface transport of hazardous materials, and as the San Bruno disaster demonstrated, there is often a lack of communication between utilities, local governments, and property owners about minimizing the risks.
These gaps are especially apparent in the process of approving new development projects. Tried-and-true systems are in place for indicating to contractors where they should and shouldn't dig to avoid making direct contact with underground infrastructure, but that information seldom takes into account what condition a pipeline is in. The general assumption is that the pipeline operator (in this case, PG&E) is keeping up with maintenance, and that it's safe to dig. Yet with the gaping questions surrounding PG&E's infrastructure in the wake of the San Bruno blast, there's a new level of uncertainty.
Pipeline safety isn't just a problem for utilities and pipeline regulators to worry about, according to a report issued by Pipelines and Informed Planning Alliance (PIPA), an initiative led by the U.S. Department of Transportation's Pipeline and Hazardous Materials Safety Administration (PHMSA), which brought together more than 100 experts in the field. It should also be on local governments' radar when they're making decisions about land use. Yet in San Francisco, this level of awareness seems to be absent.
According to PIPA, "Changes in land use and new developments near transmission pipelines can create risks to communities and to the pipelines." The hefty report contains an exhaustive set of best practices for planning near pipelines, many specifically targeting local governments. Priority No. 1 for local planning departments should be to "obtain mapping data for all transmission pipelines within their areas of jurisdiction ... and show these pipelines on maps used for development planning." The report also suggests taking special precautions in areas spanning 660 feet on either side of a gas-transmission pipeline; creating systems of communication so information can be readily shared between local governments, utilities, and landowners; and identifying emergency contacts who can halt dangerous excavation activities in case something goes wrong.
The Guardian sent e-mail queries to the Planning Department and Department of Building Inspection (DBI) to find out if the city was adhering to any of the practices recommended by PIPA as the best ways to ensure safe planning near pipelines. Reached by phone, a spokesperson from Planning told the Guardian, "DBI is where you need to call."
But DBI spokesperson Bill Strawn said, "Those questions you were asking really don't fall into the Department of Building Inspection's jurisdiction."
Strawn added that the issue of underground infrastructure is not really taken into account when building permits are issued. "We don't go to the [Public Utilities Commission] or [Department of Public Works] or PG&E" for that kind of information, Strawn said. "That would be the responsibility of the property owner, and the plans they submit to us don't include that kind of utility information."
PG&E is scrambling to meet a March 15 deadline imposed by the California Public Utilities Commission to turn over records proving its lines are intact. Until it can prove the integrity of its system either on paper or through costly, high-pressure water testing, the condition of some lines is unknown. PG&E did not return calls for comment.
In San Francisco, a densely populated urban hub on an earthquake-prone peninsula where major development projects are being permitted all the time, these issues are particularly pressing. Charley Marsteller, former chair of San Francisco Common Cause, certainly thinks so.
Last December, Marsteller penned a letter to a well-respected geotechnical engineer, raising a question about pipeline safety in light of California Pacific Medical Center's plans to construct a massive hospital at its Cathedral Hill site on Franklin Street. According to a map of underground gas lines published by the Guardian (See "PG&E's Secret Pipeline Map," 9/21/10) using several sources of data, a PG&E gas main appears to run beneath Franklin.
Marsteller was worried about whether excavation for CPMC — or other projects requiring excavation, or even simple contractor digging — could cause vibrations that could affect that pipe.
"As CPMC digs its 100-foot hole, and due to the massive construction vibrations, is there not a risk that the PG&E gas pipeline is at risk of rupture?" he wanted to know.
The engineer, who preferred not to have his name published, responded in an informal letter that "it is indeed possible that soil movement generated by excavation and/or foundation construction could rupture a deteriorated gas main." He added that while he wasn't familiar with the details of CPMC's or other excavation projects on Franklin Street, he did know that the area in question "consists of relatively weak soil" underlain at depth by a geologic feature called the Franciscan Formation, made of sandstone and fine-grained, sedimentary rock.
Yet no one seems to be giving this question any kind of professional attention or study. Eerily, Marsteller seems to be the only person in San Francisco who's asking what happens if a major excavation project is permitted nearby a corroded pipeline — and he says he hasn't received much of a response from the "rather blistering memos" he's fired off to planning commissioners and members of the Board of Supervisors to ask about it. "I'm very concerned that we're not suspending contractor digging proximate to a pipeline," Marsteller said, until PG&E can offer proof that the lines nearby excavation projects are in good shape. Whether these issues will ever be considered as part of the local planning process, Marsteller predicted: "The answer is, no one ever thinks about this."
Excavation damage accounts for nearly one-quarter of pipeline "incidents" nationwide, according to the federal Office of Pipeline Safety report. Yet safeguards are in place to prevent these things from happening.
When the Guardian initially phoned the Planning Department to ask about digging near pipelines, the phone call was returned by the Department of Public Works. Anytime a street excavation project is planned, DPW's Gloria Chan explained, a notice of intent is issued 120 days beforehand to PG&E, AT&T, the Public Utilities Commission, and any other stakeholders that might have something running underground. Projects are then designed to integrate existing lines. "Sometimes the information we get may be 40 years old," Chan said. Through a mandated process called USA Service Alert, people go out to physically mark where the underground infrastructure begins and ends on the project site before a contractor starts breaking ground.
That same process occurs with private development projects, explained Alan Kropp, a geotechnical engineer with the firm Alan Kropp & Associates. Kropp said it's left up to a private contractor to work out the technical details for digging, which are governed by a set of regulations. "If you're one foot away or three feet away, most pipes don't care," Kropp said, but he acknowledged that if a pipe is deteriorated, there could be instances where digging a normally safe distance away could still pose a problem.
"Almost all the time, the system works well," Kropp said. As for the condition of the pipe, Kropp said, that information generally doesn't guide project decisions. "It's really up to the owner of the pipeline," he said. "They would be the ones in control of that information."