"And not all operators we spoke with were aware of existing PHMSA guidance designed to assist operators in making these decisions," the report said. "PHMSA could assist operators in making this decision by formally collecting and sharing evaluation approaches and ensuring operators are aware of existing guidance."
There are approximately 2.5 million miles of pipeline in the United States that transport oil, natural gas and hazardous liquids. Since 2006, there have been about 40 serious pipeline incidents each year that resulted in a fatality or injuries.
The cause of the West Virginia explosion remains under investigation. The NTSB has said the line showed signs of external corrosion and had thinned to about one-third of the recommended thickness in some spots.
U.S. Sen. Jay Rockefeller, D-W.Va., has scheduled a hearing of the Senate Commerce Committee that he chairs to look into pipeline safety. The GAO report will be discussed at the field hearing, set for Monday in Charleston.
"We have miles and miles of pipeline beneath our feet, and we in West Virginia were reminded last month that serious accidents can and do happen," Rockefeller said Wednesday. "Responding to an accident quickly and efficiently is absolutely essential to keeping the public safe. I'm eager to review all of the GAO's findings in the days ahead."