Noting that it had invested nearly $1.5 billion during the past 26 years to replace one-third of its natural gas transmission system, Pacific Gas and Electric Co. (PG&E) attempted Wednesday to put in perspective concerns and alleged inconsistencies cited by officials regarding its work before and after a catastrophic pipeline rupture last year in San Bruno, CA.

In response to queries from NGI, a utility spokesperson said about 2,100 miles of the 6,000-mile transmission system has been replaced as part of PG&E’s pipeline replacement program, which has been ongoing since 1985. And during those years — particularly in the 1980s and 90s — the priority of various pipe testing and replacement changed frequently. Some changes were caused by major natural disasters in the San Francisco Bay Area.

More questions were raised this week about the thoroughness of the utility’s maintenance/repair and replacement efforts following a state regulatory commission staff audit released on Monday by a local congresswoman. It raised doubts about the handling over the years of Line 132, which ruptured in San Bruno (see Daily GPI, May 18).

In question is $183 million in ratepayer funds authorized by the California Public Utilities Commission (CPUC) in the late 1980s and 1990s for which CPUC staff indicate that there is no repair or replacement work accounted for, according to information that Rep. Jackie Speier (D-San Mateo County) released from the latest review of the 1987-1999 period. The CPUC said the expenditures were authorized as part of three separate PG&E general rate case decisions during the 13-year period.

In more recent years (2000-2010), PG&E has overspent on pipeline safety-related work, according to the CPUC information provided to Speier’s office.

PG&E on Wednesday confirmed that long stretches of Line 132 in San Bruno, both south and north of the ruptured segment, were replaced, but an approximate half-mile segment that included the section that failed was not replaced. The utility spokesperson also said there was no $183 million of unused funds for part of the long-term pipeline replacement effort.

“The [Line 132] project was developed and completed to address seismic concerns related to segments to the north and south of the accident site,” the PG&E spokesperson told NGI. The utility’s gas pipeline replacement program (GPRP) was established to replace pipe throughout PG&E’s territory, using a “prioritization model,” she said.

“This model was developed jointly between PG&E operations and our geosciences department and [it] established prioritization factors that included pipe material or welding techniques, leak history, presence of cathodic protection on the pipe, structure and population proximity and seismic vulnerability.”

For Line 132 in San Bruno, the geosciences unit focused on seismic risks and a GPRP project was developed and completed to address seismic concerns specifically in that area, the spokesperson said. “Based on our program criteria, the segment involved in this terrible tragedy was not part of the project.”

In the 1985-1999 time period PG&E acknowledges that it spent less than was originally forecast for the GPRP, but the spokesperson said it is “important to note” that the utility kept the pipeline program on schedule throughout those years. “At the approximate halfway point, PG&E had replaced 57% of the transmission pipe in the GPRP. We were getting more efficient at replacing gas transmission lines.”

Currently, more than a decade later, PG&E cannot trace precisely whether all of the GPRP funds were spent, but the spokesperson contends that the utility is certain it spent money on “the highest priority work to maintain the safety and reliability of its system.”

For instance, she said, projects that were deemed high priority included those to deal with the 1989 Loma Prieta earthquake and the 1991 Oakland Hills firestorm, as well as reappropriating funds to accommodate customer growth when it exceeded forecasts.

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