The pipe that ruptured Tuesday afternoon had less than a third of the wall strength it was supposed to. That was one of the findings made by members of the National Transportation Safety Board as they continue their investigation into what caused the massive natural gas explosion.
At 12:41 p.m. Tuesday, Columbia Gas and its parent company NiSource were notified that there was a drop in pressure in the pipe. Exactly how far of a drop is not yet clear. Shortly after, 911 was first contacted by someone at the Charleston facility. Federal investigators said in a news briefing Thursday that they are continuing investigations into the pipeline will focus on interviews with members of Columbia gas.
The thinned piece of piping will be shipped to Washington D.C. for analysis where they hope to find out what caused the blast. It is unclear if the thinning of the pipe was related to the explosion or was there earlier.