Persistent problems with Pacific Gas & Electric’s locate-and-mark practices might have contributed to 67 occasions where people hit underground lines while digging, according to new testimony from safety investigators.

The California Public Utilities Commission in December launched an investigation into alleged locate-and-mark violations committed by PG&E employees. State law requires gas pipeline operators to identify and mark their underground facilities within two working days of being notified of any planned excavation activities (see CEM No. 1519 [11]).

According to the CPUC’s Safety and Enforcement Division, PG&E employees were repeatedly tweaking records to conceal the fact that certain sites had not been visited on time, leading to an undercounting of “late tickets.” In testimony filed with the commission on July 24, the division said late tickets could have contributed to as many as 67 dig-ins, or instances where an excavator struck underground gas infrastructure. The division noted that while PG&E’s senior leadership “seemed” unaware of the issues, management within the locate-and-mark department knew that the records were being manipulated.

According to an analysis conducted by Bates White, an economic consulting firm recruited by PG&E, there were 325 instances where a dig-in occurred on a site that had not been marked on time. In 258 cases, PG&E found that the late tickets were not a contributor to the accident; however, in 67 cases, they could not rule that out.

SED also pushed back against PG&E’s claims that it had successfully reduced its rate of dig-ins over the last few years. The division noted that while the dig-in “rate” decreased, the number of instances of excavation damage did not—in fact, the number of instances of damage increased from 1,534 in 2012 to 1,874 in 2017.

Kavya Balaraman covers the California Public Utilities Commission and PG&E Corp. for California Energy Markets. She has reported on climate policy and science in Washington, D.C. and graduated from Columbia University's Graduate School of Journalism.