Feds: Ruptured W.Va. pipe may have been corroded - Article Photos 2/4

This image provided by the National Transportation Safety Board Wednesday Dec. 12, 2012 shows investigators looking over a 20-foot-long section of pipe found more than 40 feet from the rupture site in Sissonville, W.V. The 20-inch transmission pipe exploded around midday Tuesday, destroying four homes, cooking a section of Interstate 77, a major north-south commuting corridor that passes through the capital city, and creating a crater 17 feet deep. (AP Photo/NTSB)