Pipeline rupture caused by manufacturer's defect, MVP report says (2024)

A rupture of the Mountain Valley Pipeline during pressure testing in May was caused by a manufacturer’s defect in an elbow joint, a fitting used to accommodate a curve in the pipe, according to an analysis released Thursday.

The failure was an isolated incident, the project’s owner said in a letter to the Pipeline and Hazardous Materials Safety Administration (PHMSA), and there is no risk of a similar incident in the future.

“The pipeline is considered to be stable for purposes of any material defect,” Justin Trettel, vice president of EQT Midstream, wrote in the letter.

Trettel’s letter was accompanied by a 43-page report from DNV, a quality assurance and risk management company hired by Mountain Valley to conduct an independent investigation of the May 1 incident on Bent Mountain in Roanoke County.

DNV said in its report that the failure was caused by weakness in a joint installed at a point where the pipe curved at a 36-degree angle. “The pipe section ruptured along the seam weld of the elbow fitting,” the report states.

At the time, water was running through the pipe at 2,105 pounds per square inch gauge.

The elbow joint and a nearby sister fitting, which was removed from the pipe for analysis, were the only two devices with a matching pedigree from the manufacturer, identified in the report as Custom Alloys. A call to the company Thursday was not immediately returned.

Of more than 2,500 such fittings installed on the 42-inch diameter buried pipeline, the elbow joint on Bent Mountain was the only one to fail during systemwide hydrostatic testing, Trettel wrote in his letter.

But to pipeline opponents, the findings raise questions about the pipe’s integrity.

“The lab hired by MVP blames the rupture on weak steel and a defective weld. This is a pathetically predictable outcome; we know the MVP has used shoddy materials for their rushed construction job on this massive methane pipeline project,” Russell Chisholm, co-director of the Protect Our Water, Heritage, Rights coalition, said in a written statement.

But according to the DNV report, “there was no evidence of external or internal corrosion” on the damaged section of pipe, which was installed in the summer of 2018.

In October, PHMSA ordered Mountain Valley to conduct additional testing of the pipe. At the time, the safety agency wrote in a consent order that conditions may exist that “pose a pipeline integrity risk to public safety, property or the environment.”

The order mentioned explosions of other pipelines in landscapes similar to the mountainous terrain through which Mountain Valley passes on its path from northern West Virginia, through the New River and Roanoke Valleys, to connect with an existing pipeline near the North Carolina line.

All of the potential problems were corrected, PHMSA said in giving the project a green light in June, shortly before the Federal Energy Regulatory Commission issued a final approval for the pipeline to go into operation.

A PHMSA spokesperson could not be reached Thursday.

In his statement, Chisholm said the report on the May 1 rupture “is yet more evidence of the threat MVP poses to everyone along the route, and why the government never should have greenlit this corrupt project.”