The utility was charged with violating federal pipeline safety laws, including failing to identify all potential threats to the aging, high-pressure line that sparked the disaster and not maintaining proper repair records, according to the indictment filed in U.S. District Court in San Francisco.
Federal authorities said the violations could carry a total fine up to $6 million.
The explosion — which sparked a wind-driven fire that set trees ablaze and illuminated the evening sky for miles — injured 58 people and destroyed or damaged dozens of homes in the suburb about 12 miles south of San Francisco. The blast left a crater 67 feet long and 26 feet deep; it flung a 28-foot section of pipe 100 feet.
"The citizens of Northern California deserve to have their utility providers put the safety of the community first," U.S. Atty. Melinda Haag said in a statement.
Connie Jackson, San Bruno's city manager, said she hoped that the indictment would bring "a measure of justice and closure for the citizens and victims."
"We've taken accountability [for the accident] and are deeply sorry," PG&E Chairman and Chief Executive Tony Earley said in a statement. "We have worked hard to do the right thing for victims, their families and the community, and we will continue to do so."
The grand jury indictment alleges that PG&E knew before the explosion that it lacked complete data for its pipelines because some records were missing and others contained errors and omissions. Prosecutors said the files were supposed to document key operations and details, such as pressure tests and areas where population centers abutted pipeline routes.
The utility was alerted repeatedly by employees and officials with the
"Despite knowledge of these deficiencies, PG&E did not keep a record-keeping system for gas operations that would ensure that pipeline records were accessible, traceable, verifiable, accurate and complete," the indictment said.
The utility also "failed to gather and integrate all relevant data for many of its older transmission lines" — including maintenance history, pressure fluctuations and threats created by age and corrosion, according to the indictment.
Federal authorities said PG&E was aware that more than 80 miles of gas transmission pipelines had never been pressure tested and had "manufacturing threats" that could create problems during unplanned pressure increases.
The utility provides natural gas to customers through 46,000 miles of distribution and transmission lines, the indictment said. The transmission line that ruptured in San Bruno was installed between 1944 and 1948.
After the disaster, the NTSB determined that maintenance work at a pipeline control center had triggered electrical problems and created a rise in gas pressure before the blast.
The agency issued a scathing report, blaming PG&E for "baffling" mistakes, a "litany of failures" and lax oversight. For example, it detailed how the company had taken nearly 95 minutes to shut off the gas that spewed from the broken pipeline.