PG&E Knew Pipeline Data Was Flawed, Feds Say

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     SAN FRANCISCO (CN) — Pacific Gas and Electric knowingly relied on a flawed record system to make safety decisions for its gas pipelines, a federal prosecutor suggested Wednesday.
     While questioning the fourth witness in a criminal trial over PG&E’s alleged violation of pipeline safety laws, U.S. Assistant Attorney Hallie Hoffman showed jurors emails from PG&E employees who voiced concern about the company’s faulty Geographic Information System, or GIS.
     “There are a ton of errors in GIS for transmission lines 101, 109 and 132,” PG&E engineer Drew Kelly wrote in an email dated March 23, 2009.
     Line 132 is the pipeline that exploded in a San Bruno neighborhood in September 2010, killing eight people and destroying 38 homes.
     Another email from December 2009 stated that two PG&E employees were “under the impression” that data from the record system was not correct.
     “Many times we run with GIS information after no more than a confirmation of wall thickness in the field,” PG&E employee Brian McCoy wrote in a Dec. 15, 2009, email. Still, McCoy concluded his email by saying, “Got to trust something, though.”
     Hoffman showed the emails while questioning PG&E senior engineer Todd Arnett on the eighth day of the criminal trial.
     In 2008, Arnett was tapped to “verify” the maximum allowable pressure on Line 132 by spiking the pressure to 400 psig, or pounds of pressure per square inch. The line was typically operated at a pressure of 375 psig.
     “So you were deliberately raising pressure on lines in high-concentration areas to verify the [maximum allowable operating pressure]?” Hoffman asked Arnett.
     Arnett answered yes, clarifying that the company only raised pressure on lines in populated areas with “certain characteristics.”
     PG&E felt compelled to spike pressure on older pipelines every five years to maintain higher capacity on those lines, a former PG&E employee testified last week.
     The utility adopted that practice because a “grandfather clause” established under the 1968 Gas Pipeline Safety Act allows lines installed before 1971 to operate at the highest pressure experienced within the last five years.
     Still, federal prosecutors say new pipeline safety laws that took effect in 2004 required PG&E to inspect the line for safety problems and conduct a strength pressure test to determine the pipe’s maximum allowable pressure.
     Hoffman showed Arnett a pipe-data record with several categories of information, including joint efficiency, girth weld, wall thickness and size.
     “Do these characteristics help determine how much pressure you can run on a pipe?” Hoffman asked.
     “Yes,” Arnett replied.
     Hoffman then showed the witness a pipeline survey sheet for Segment 180, the part of Line 132 that blew up in San Bruno in 2010. The document had missing data for several categories of information. It also had a minus sign to note that the specified minimum yield strength, or minimum stress a pipe can withstand before deforming, was an assumed value that was not confirmed.
     “Did you look into a manufacturing or construction threat on Line 132?” Hoffman asked Arnett. “Did you look into missing leak repair information?”
     “No,” the senior engineer replied.
     Hoffman showed more email exchanges between PG&E employees debating whether it was worth the cost and effort to “verify the pressure” of Line 132 in 2008 by spiking the pressure to 400 psig.
     It cost $45,471 to coordinate engineers to isolate the line and raise the pressure to 400 psi for two hours, according to a job scope document Hoffman showed the jury.
     “I believe we need to do whatever it takes to keep the line at 400 psig,” PG&E engineer Jason Reider wrote to Arnett in a November 2008 email.
     On Dec. 9, 2008, Arnett received an email confirming that the pressure had been spiked and verified. Less than two years later, the pipeline exploded in San Bruno. More than 100 homes were also damaged.
     The jury did not hear that the line being discussed was the same one that exploded in 2010, however. U.S. District Judge Thelton Henderson barred prosecutors from making the cause of the explosion an issue in the case, finding that the cause of the blast is not an element of any accused crime.
     PG&E faces 12 counts of violating recordkeeping and testing requirements under the Pipeline Safety Act and one count of obstructing an investigation into the cause of the explosion.
     If convicted, the utility company faces a $562 million fine.
     Last year, the California Public Utilities Commission fined PG&E $1.6 billion, the largest penalty ever assessed against a utility company in the state’s history.
     The criminal trial is expected to continue until mid-August.