SAN FRANCISCO (WKOW) -- An investigation into the explosion that killed at least four people near San Francisco shows the pipeline was known to be dangerous.
In 2007, the gas company ranked in the top 100 riskiest lines and listed its risk failure as "unacceptably high."
According to the federal agency overseeing the nation's pipelines, there were 265 "significant incidents" in 2009 alone and 14 deaths.
Many lines are 40, 50 or 60 years old and need to be replaced.
SAN FRANCISCO (WKOW) -- Officials still aren't sure just how many people died in the explosion and fire that destroyed dozens of homes in a neighborhood near San Francisco Thursday.
The remains of at least four people have been found. Authorities say four people are missing.
Residents were allowed to return to their damaged homes Sunday, accompanied by gas workers to help restore pilot lights and make sure it was safe to turn the power back on.
California regulators are telling Pacific Gas and Electric to survey all of its natural gas lines in the state, in hopes of heading off another disaster.