SAN BRUNO (CBS/AP) – Corrosive microbe gases are being investigated as a possible cause of the San Bruno natural gas pipeline explosion that killed seven people and destroyed 37 homes this month.
The San Francisco Chronicle reported Pacific Gas & Electric told state regulators last year that there were concerns about microbiological influenced corrosion on the 46-mile line running from San Francisco to Milpitas, which included the portion that ruptured on Sept. 9.
Destructive microbes can lie dormant for years before springing to life in water at the bottom of a pipe and going to work on the metal, according to pipe-corrosion experts.
The old pipe in San Bruno, which was installed in 1956, would likely have corrosion-causing microbes hiding inside it, said Environmental microbiologist Laura Kentala.
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