On August 1, Enbridge’s Texas Eastern Pipeline Company (TETCO) pipeline exploded in Lincoln County, Kentucky–killing one and sending six to the hospital (see TETCO Pipe Explodes in Kentucky Killing 1; Southbound M-U Gas Stops). Since that time one of the three TETCO pipes in the area has returned to service. The federal Pipeline and Hazardous Materials Safety Administration (PHMSA) continues to investigate. As is typical for such an investigation, we won’t have an official determination for months, maybe even a year, as to what caused the explosion. However, Enbridge is saying the explosion is likely due to a certain kind of pipe manufactured back in the 1950s.