Engineering ExpertA Pipeline and Hazardous Materials Safety Administration senior engineer for the prosecution in the case against a natural gas company over the 2010 San Bruno explosion. The defendant was found guilty on five felony counts of failing to adequately inspect its gas pipelines. The utility company was also found guilty of misleading federal investigators about the standards used in monitoring old pipelines. The blast killed eight people, seriously injured thirty-eight, and destroyed fifty-eight homes.

The cause of the explosion was found to be a bad internal seam weld in a pipeline installed in the 1950s. In court, defendant alleged their system had no such weld. The National Transportation Safety Board has announced a fine of $562M. The utility company has already paid $1.6M in fines to state regulators and more than $500M in private settlements.

The National Transportation Safety Board’s investigation found that the rupture of Line 132 was caused by a fracture that originated in the partially welded longitudinal seam of one of six short pipe sections, which are known in the industry as “pups.” The fabrication of five of the pups in 1956 would not have met generally accepted industry quality control and welding standards then in effect, indicating that those standards were either overlooked or ignored. The weld defect in the failed pup would have been visible when it was installed. The investigation also determined that a sewer line installation in 2008 near the rupture did not damage the defective pipe.

Engineering expert witnesses are trained to investigate and consult on safety testing for utility companies. They are knowledgeable and able to testify on safety regulations and procedures used in the industry to identify high risk pipelines. In this case, the engineering expert testified that safety procedures used by the utility company were a violation of federal law.


By:  Karen Olson, 20+ years of experience in legal research