A ball of flames and smoke in a San Bruno neighborhood are seen from a distance on September 9, 2010. (AP)
San Bruno Explosion
Neighbors watch as a ball of flames and smoke go through a San Bruno neighborhood on September 9, 2010. (AP)
San Bruno Explosion
Flames and a smoke plume rise from a massive fire in a residential neighborhood September 9, 2010 in San Bruno, California. (Getty Images)
San Bruno Explosion
Firefighters monitor flames from a massive fire in a residential neighborhood September 9, 2010 in San Bruno, California. (Getty Images)
San Bruno Explosion
A firefighter carries equipment as he battles a massive fire in a residential neighborhood September 9, 2010 in San Bruno, California. (Getty Images)
San Bruno Explosion
Flames and a smoke plume rise from the massive fire in a residential neighborhood September 9, 2010 in San Bruno. (Getty Images)
San Bruno Explosion
San Francisco firefighters monitor flames from a massive fire in a residential neighborhood September 9, 2010 in San Bruno, California. (Getty Images)
San Bruno Explosion
A law enforcement official runs towards a massive fire in a residential neighborhood September 9, 2010 in San Bruno. (Getty Images)
San Bruno Explosion
A law enforcement official talks on the radio near a massive fire in a residential neighborhood September 9, 2010 in San Bruno, California. (Getty Images)
San Bruno Explosion
Flames several stories high roar through a San Bruno neighborhood, following the gas line explosion September 9, 2010. (AP)
San Bruno Explosion
A firefighter is seen running as a massive fire roars through a San Bruno neighborhood. (AP)
San Bruno Explosion
Two firefighters assess the flames resulting from the gas line explosion in San Bruno on September 9, 2010. (AP)
San Bruno Explosion
Firefighters look on as a CalFire helicopter drops water on a massive fire in a residential neighborhood September 9, 2010 in San Bruno, California. (Getty Images)
San Bruno Explosion
A firefighter stands on the roof of a home as the massive fire roars through a residential neighborhood in San Bruno on September 9, 2010. (AP)
San Bruno Explosion
Firefighters douse a massive fire, following an explosion in a San Bruno neighborhood on September 9, 2010. (AP)
San Bruno Explosion
A Daly City firefighter assesses the fire resulting from a massive gas explosion in San Bruno on September 9, 2010. (AP)
San Bruno Explosion
Firefighters on the scene as a massive fire roars through the San Bruno neighborhood on September 9, 2010. (AP)
San Bruno Explosion
A fire burns where remains of homes and automobiles consumed by a massive fire in a residential neighborhood are scattered on September 9, 2010 in San Bruno. (Ezra Shaw/Getty Images)
San Bruno Explosion
A firefighter tries to contain part of a massive fire that took place on September 9, 2010 in San Bruno. (Ezra Shaw/Getty Images)
San Bruno Explosion
Firefighters examine a residential neighborhood where a massive fire took place on September 9, 2010 in San Bruno. (Ezra Shaw/Getty Images)
San Bruno Explosion
Firefighters walk through a residential neighborhood where a massive fire took place on September 9, 2010 in San Bruno. (Ezra Shaw/Getty Images)
San Bruno Explosion
Firefighters continue to work after a massive fire in a residential neighborhood September 9, 2010 in a San Bruno. (Max Whittaker/Getty Images)
San Bruno Explosion
California firefighter Martin Medina mops-up a fire during a massive fire in a residential neighborhood September 9, 2010 in a San Bruno. (Max Whittaker/Getty Images)
San Bruno Explosion
A crater filled with water marked the site of an explosion that caused a fire the massive fire burning in a residential neighborhood September 9, 2010 in a San Bruno. (Max Whittaker/Getty Images)
San Bruno Explosion
Chimneys, burnt-out cars and a real estate for sale sign remain after a massive fire in a residential neighborhood September 9, 2010 in a San Bruno. (Ezra Shaw/Getty Images)
San Bruno Explosion
A firefighter walks around the massive fire in a residential neighborhood September 9, 2010 in a San Bruno. (Max Whittaker/Getty Images)
San Bruno Explosion
Firefighters work to contain and mop-up a fire during a massive fire in a residential neighborhood September 9, 2010 in a San Bruno. (Max Whittaker/Getty Images)
San Bruno Explosion
Chimneys remain during a massive fire in a residential neighborhood September 9, 2010 in a San Bruno. (Max Whittaker/Getty Images)
San Bruno Explosion
A crater filled with water, marking the site of an explosion that caused a fire the massive fire burning in a residential neighborhood September 9, 2010 in a San Bruno. (Max Whittaker/Getty Images)
San Bruno Explosion
California firefighter Martin Medina mops-up a fire during a massive fire in a residential neighborhood September 9, 2010 in a San Bruno. (Max Whittaker/Getty Images)
San Bruno Explosion
Chimneys and a real estate for sale sign remain after a massive fire in a residential neighborhood September 9, 2010 in a San Bruno. (Max Whittaker/Getty Images)
San Bruno Explosion
Firefighters work to contain and mop up a fire during a massive fire in a residential neighborhood September 9, 2010 in a San Bruno. (Max Whittaker/Getty Images)
San Bruno Explosion
Flames from a massive fire are seen in a residential neighborhood September 9, 2010 in San Bruno. (Getty Images)
San Bruno Explosion
Flames consume homes during a massive fire in a residential neighborhood September 9, 2010 in San Bruno. (Getty Images)
San Bruno Explosion Map
Neighborhood where homes were either destroyed or damaged by the explosion. (CBS)
San Bruno Explosion Aftermath
Firefighters investigate a massive crater at the scene of a gas main explosion Friday in San Bruno. (Justin Sullivan/Getty Images)
San Bruno Explosion Aftermath
Firefighters sift through rubble Friday at burned homes destroyed by a massive gas main explosion and fire in San Bruno. (Justin Sullivan/Getty Images)
San Bruno Explosion Aftermath
SAN BRUNO, CA - SEPTEMBER 13: A couple walks by homes that were destroyed by fire following a deadly gas main explosion on September 13, 2010 in San Bruno. (Justin Sullivan/Getty Images)
San Bruno Explosion Aftermath
A charred car sits in the driveway of a home that was destroyed by fire following a deadly gas main explosion on September 13, 2010 in San Bruno. (Justin Sullivan/Getty Images)
San Bruno Explosion Aftermath
Officials look on as Pacific Gas & Electric workers excavate the crater at the epicenter of a deadly gas main explosion September 13, 2010 in San Bruno. (Justin Sullivan/Getty Images)
San Bruno Explosion Aftermath
A charred Buddha statue sits in the yard of a home that was destroyed by fire following a deadly gas main explosion on September 13, 2010 in San Bruno. (Justin Sullivan/Getty Images)
San Bruno Explosion Cleanup
An American flag flies over a a burned home near the epicenter of the gas line explosion that devastated a San Bruno neighborhood. (Justin Sullivan/Getty Images)
San Bruno Explosion Cleanup
An excavator moves the shell of a destroyed car at a burned home near the epicenter of the gas line explosion that devastated a San Bruno neighborhood. (Justin Sullivan/Getty Images)
San Bruno Explosion Cleanup
A chimney is all that remains at a burned home near the epicenter of the gas line explosion that devastated a neighborhood in San Bruno. (Justin Sullivan/Getty Images)
San Bruno Explosion Cleanup
Workers talk as they stand next to burned homes near the epicenter of the gas line explosion September 24, 2010 in San Bruno. (Justin Sullivan/Getty Images)