"Federal investigators' findings in the San Bruno pipeline explosion probe suggest that thousands of miles of long-buried and untested natural gas pipelines across the United States are at far greater risk of failure than the industry and government regulators have long maintained, experts say.

'It's a wake-up call,' Robert Eiber, a pipeline integrity expert with 50 years of experience in the industry, said of the implications of the National Transportation Safety Board's metallurgical analysis of the line that exploded Sept. 9.

'They need to make sure they don't have a duplicate situation someplace else,' Eiber said. 'If it has not been tested, you need to test it.'

In a detailed report released Jan. 21, the safety board identified a 'progressive' crack on a seam running several feet along the San Bruno line as the point where the 30-inch transmission pipe ruptured, causing a fireball that killed eight people and destroyed 38 homes. The crack began at a shoddy weld that extended only halfway through the pipe wall, investigators said."

Jaxon Van Derbeken and Eric Nalder report for the San Francisco Chronicle January 30, 2011. [2]