SAN FRANCISCO (KCBS) – Pacific Gas and Electric considers 239 of its natural gas transmission lines to be at risk of failing – in a fashion similar to the line that exploded in San Bruno almost two years ago.
According to a company assessment obtained by the San Francisco Chronicle, PG&E has identified more than 500 trouble spots on those lines. Those spots range from a few feet in length to more than a mile. They include pipe seam welds susceptible to failing because they are old or because the company pressurized the pipes beyond legal limits without testing them afterward for possible problems.
The pipes include several lines running along the Peninsula, including the one that exploded in San Bruno and one in the East Bay between Sunol and Livermore.
PG&E plans to replace some lines and and test others.
According to the Chronicle, the company reached its conclusion after commissioning a study of its 1,000 mile network of gas transmission lines in urban areas. Engineers with PG&E and its consulting company, Kiefner & Associates, reviewed inspection histories and pipeline records.
KCBS’ Tim Ryan Reports:
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