The federal judge overseeing PG&E’s probation for federal safety law violations on Monday ordered the bankrupt utility to explain how a previously inspected jumper cable on a transmission tower could have failed in high wind, apparently sparking the 78,000-acre Kincade wildfire.
U.S. Judge William Alsup gave the company until Nov. 29 to answer questions “all of which are intended to gather information to assess its compliance with conditions of probation.”
The company’s probation stems from its conviction of federal pipeline safety violations arising out of the 2010 San Bruno gas pipeline explosion that left eight people dead.
The judge also asked that the company detail the equipment failure and tree damage it found to its system during the two power shutoffs late last month, including the one it started on the night the Kincade Fire broke out on Oct. 23.
The company had shut off distribution lines nearby but said forecast winds were not strong enough to shut down transmission lines based on the company’s protocols.
Alsup asked the company to detail under what conditions a cable could separate, triggering lightning-like bursts of energy known as arcing.
“If a jumper cable separates and falls away from an energized transmission line, will any arcing or sparking plausibly occur, even briefly, between the energized line as it falls away?” the judge asked. “If a jumper cable becomes disconnected from an energized line, what other scenarios could plausibly produce sparking or arcing?”
He asked what could cause the jumper to separate from the line and for the utility to specify who inspected the tower last and how the check was performed. CEO Bill Johnson has said the tower was twice inspected this year, and the jumper that failed had been found to be in good condition.
“Should we now be worried that other jumper cables inspected in the same manner have potential failures that have gone undetected?” the judge asked. “How many structures have been lost and how many lives have been lost by wildfires arguably caused by PG&E distribution lines in 2019?”
The judge suggested the number so far will be lower than before due to planned power shutoffs, “but the Court (and the public) would appreciate a more precise answer.”