Federal investigators are working to piece together what caused the gas pipeline blast and fire that killed eight people and destroyed 37 homes in San Bruno last month.
Though the causes of the disaster are not completely established and can take up to a year, it raises concerns about whether the regulations, meant to prevent such tragedies, were obeyed by the company.
PG&E charged its customers $5 million to fix a gas pipeline under San Bruno in 2009, but delayed the work citing other priorities, according to the Utility Reform Network (TURN), a utility watchdog.
Was PG&E Cost Cutting?
The utility failed to perform a scheduled replacement on a pipe nearby where the explosion occurred. They also failed to install automatic shut-off valves, which might have significantly reduced the destruction from the explosion. PG&E workers say it took them almost 2 hours to close valves on the 30 inch section manually, requiring workers to enter a secured room, attach an arm to the valve and then physically close it off.
According to TURN, a 2009 report indicates PG&E was aware of the danger. Company officials wrote, “If the replacement of this pipe does not occur, risks associated with this segment will not be reduced. Coupled with the consequences of failure of this section of pipeline, the likelihood of a failure makes the risk of a failure at this location unacceptably high.”
Investigative Panel Assembled
An independent panel has been appointed by California regulators to investigate the explosion, according to The Washington Post. The five-member panel will focus on systemic problems within PG&E that could have contributed to the explosion.
Pipeline Inspection and Safety
Pipeline companies must routinely inspect their pipelines for corrosion and defects. To do so, sophisticated pieces of equipment known as “smart pigs” are used. They can test pipe thickness, roundness, detect leaks and other defects along the interior of the pipeline that may impede the flow of gas.
In addition to the use of smart pigs, there are numerous safety precautions and procedures put in place to minimize the risk of accidents. Together, gas utility and pipeline companies spend close to $7 billion per year to ensure that natural gas is delivered safely and reliably.
A few safety precautions associated with natural gas pipelines include:
Natural gas detecting equipment should be used periodically on the surface to check for leaks. This is particularly important in areas where natural gas is not odorized.
Federal pipeline safety code requires that distribution systems comply with tough requirements for design, construction, testing, inspection, operations and maintenance from the point of connection to the point of transmission, up to and including the customer’s meter.
Natural gas distribution pipes typically are regulated by both federal and state agencies. Distribution systems regulated by a state agency are required by law to comply with standards that are as stringent as or more stringent than those set forth in federal minimum safety mandates.
Preventative maintenance involves routine testing of valves as well as the removal of surface impediment to pipeline inspection.
To read more about natural gas and safety measures visit NaturalGas.org.