Pacific Gas and Electric Co. (PG&E) on Monday finished lowering the pressure on a natural gas transmission pipeline on the peninsula south of San Francisco in response to a court order initiated over the weekend by the city of San Carlos. It is the same pipeline connected to the line that failed three years ago in nearby San Bruno, prompting recent state regulatory reaction against PG&E.
San Carlos officials and the California Public Utilities Commission (CPUC) met Monday to determine the future of the pipeline as a high-pressure transmission lateral, and city manager Jeff Maltbie indicated that San Carlos plans to hire its own technical and legal experts to evaluate PG&E's documentation of the pipeline.
The court action was prompted when San Carlos city officials on Friday declared an emergency in response to internal PG&E e-mails among utility engineers that expressed concerns about the 24-inch diameter, 3.8-mile pipeline lateral (Line 147) connecting separate 30-inch diameter lines (132 and 101) that run south-to-north up the peninsula.
Noting that the pipeline is safe and was thoroughly hydrostatically and pressure tested two years ago in the wake of the San Bruno pipeline failure and explosion on a segment of Line 132, PG&E officials said Monday they were in the process of lowering the lateral's pressure to around 125 psi from around 300 psi. The combination utility needs to keep some pressure in the line to serve local needs and in case the line would have to be repressurized quickly to meet a sudden gas system need, a utility spokesperson told NGI.
Natural gas utility service on the peninsula will be unaffected by the pressure drop, the utility spokesperson said.
Based on the internal e-mails that again showed that PG&E had incorrectly identified a pipeline segment in which its records did not match the 83-year-old pipeline's actual characteristics, San Carlos declared the emergency and Maltbie called an emergency meeting of the town's city council. After PG&E refused to voluntarily shut down the pipeline lateral, the city sought and got the court injunction. City officials publicly criticized PG&E for not immediately shutting down the line as a transmission pipeline.
In September, the CPUC held two hearings related to the identification and subsequent reporting to the regulatory commission of a Line 147 record keeping error by PG&E (see Daily GPI, Sept. 6).
PG&E's spokesperson stressed then and with the current situation that there has never been any safety problem involved, and the utility wants its employees to continue to raise issues when they see mistakes in the handling of records and any other aspects related to the safety of the utility's massive gas pipeline system.
Late Sunday night San Carlos reported that PG&E had complied with the court injunction by taking Line 147 down to distribution-level pressure. "The lower pressure reduces the risk of a catastrophic explosion along the pipeline," the city officials said.
Since the PG&E engineer's e-mails surfaced last November, city officials and state and congressional elected officials have been leading the charge in questioning the utility's handling of its pipeline safety enhancement efforts, their costs and who ultimately pays for them (see Daily GPI, Aug. 23; June 7;May 29).