Mountain Valley Pipeline: "Uniquely Risky"

Steel pipelines used to transport fossil fuels are prone to corrosion. Contaminants in oil or gas, such as hydrogen sulfide and carbon dioxide, can cause corrosion on the inside of the pipes. Rain and dew can cause corrosion on the exterior of pipes when they are stored outdoors. Soil constituents and groundwater can cause corrosion on the exterior of pipes when they are buried beneath the surface, with wet areas more susceptible to corrosion than dry areas.

Corrosion in a pipeline is extremely dangerous, leading to catastrophic explosions and death. Indeed, corrosion problems are the second greatest cause of pipeline failures.

MVP pipe in water near a home in Franklin County, VA: according to a local landowner, this pipe was left in a trench that sometimes filled with water up to 2 feet high, for more than a year, until the trench was dewatered

Preserve Bent Mountain

Fortunately, coatings can be applied to pipes to help protect against corrosion. Ideally, pipes are coated both internally and externally to protect from both types of corrosion. Unfortunately, federal regulations only require external coatings for oil and gas pipelines. And pipe coating is not permanent or indestructible. It has to be carefully maintained to retain its protective qualities. If coated pipes are stored outdoors and exposed to the elements, the pipe coating can degrade due to rain, wind, and—especially—ultraviolet (UV) rays from sunlight. As coating degrades, its protective function also diminishes. Even a tiny imperfection in the coating can create a concentrated area of accelerated corrosion.

The rate and extent of coating degradation will vary by the particular circumstances at a site, but according to the National Association of Pipe Coating Applicators: “Above ground storage of coated pipe in excess of 6 months without additional Ultraviolet protection is not recommended.” A 2020 study found that coated pipes that were not provided with additional protection and were exposed to UV rays for many years beyond the recommended six-month maximum “completely failed to retain their original properties and attributes” and were “no longer fit for purpose."1

Mountain Valley Pipeline coatings

Mountain Valley Pipeline (MVP) is a partially completed pipeline that would have high explosive risk if it is completed and enters operation. Its large diameter and high pressure are enough to make it a higher risk pipeline than most other gas transmission pipelines. This risk is further increased by the steepness of the Appalachian mountain slopes it would traverse for long distances. MVP is designed to traverse 75 miles of the steepest slopes in Appalachia and more than 200 miles with “high landslide susceptibility,” which places it at higher risk for explosions. This has never before been attempted for a large gas pipeline. 

Taking all of this into consideration, MVP is perhaps the riskiest new pipeline construction project in the country. Indeed, it’s been called “uniquely risky” by an environmental hydrologist. This is not a hypothetical risk. MVP has already caused dozens of “slips” where a slope has become unstable, including slopes outside of the pipeline’s right-of-way. And, in 2019, MVP itself reported that a landslide along the pipeline route “progressed to the point where a residence directly downslope is unsafe to be occupied.” 

Image of pipeline construction on steep slope
MVP construction on a steep slope in the Adney Gap area of Franklin County, VA, with a home below

Preserve Bent Mountain

Pipes for the Mountain Valley Pipeline (MVP) were purchased years ago. From company testimony in a 2018 court hearing, it appears that they were ordered before the project had even obtained a certificate of approval from the Federal Energy Regulatory Commission.2 The pipes are primarily coated with 3M Scotchkote Fusion Bonded Epoxy (FBE) 6233 coating. Many are still being stored outdoors throughout the pipeline route in Virginia and West Virginia; some are sitting in trenches in the ground and some are stacked in storage yards. Each separate pipe is stamped with the “date of coating.”

MVP pipe has coating date stamps from as long ago as December 2016—six years ago. Local citizens report they have not come across any pipe dated later than 2017.

MVP pipe with 2016 date stamp in Franklin County, Virginia

Preserve Bent Mountain

According to the Pipeline Safety Trust, “There are significant concerns about the effectiveness of the FBE epoxy coatings on the pipeline segments that have been exposed to sun and weathering for far longer than recommended by the manufacturer.” MVP’s coated pipe has been exposed to the elements for up to six years because of the pipeline owner’s bullish decision to purchase and coat the pipes before resolving outstanding issues regarding the unlawfulness of its design and permits issued by federal agencies during the Trump Administration.

MVP claims that they will inspect the pipe and repair any damaged coating or thin spots on exposed pipe before installing it in the ground. But there aren't any federal regulations that specify standards for repair. According to the Pipeline Safety Trust, “The regulations are written to largely allow the operator to determine if the coating is appropriate as opposed to prescribing exactly what would make a coating safe or unsafe.” When pipes for the proposed (and now cancelled) Keystone XL pipeline were stored outdoors for approximately six years due to delay, a company representative stated that any pipe determined to need recoating would have to be transported back to a plant to be stripped and recoated. That requires time—and money. Given that MVP is already more than $3 billion over budget and more than five years behind schedule, the company has incentive to cut corners.

Leaving pipeline inspection and repair up to the pipeline company is simply wrong.

The communities along the route need to able to sleep at night with confidence that their lives and those of their loved ones are being considered—the most important purpose of the coatings. These pipes are sitting on private property that belongs to real people who live in what is known as the “blast zone”—the distance from an explosion where death or serious injury is likely. And they won’t be able to sleep at night knowing that a pipeline company that has been fined millions of dollars for hundreds of state alleged violations is allowed to decide how to address the risks associated with deteriorating pipe coating that has been exposed to the elements for far too long.


Keith Coulson, James Ferguson, and David Milmine, “Study of stockpiled fusion bond epoxy coated pipe,” in Corrosion Management, Institute of Corrosion, January/February 2020.

Mountain Valley Pipeline, LLC, Plaintiff, vs. Sharon Simmons, et al, Defendants, Civil Action Number: 1:17CV211, Proceedings had in the Motion Hearing on January 23, 2018. 

About the Authors

Amy Mall

Senior Advocate, Dirty Energy, Lands Division, Nature Program

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