A series of drilling-mud releases along the Mariner East 2 Pipeline construction route have raised a lot of speculation about potential risks associated with energy transportation lines.
While it is important that communities in Cumberland County and across central Pennsylvania understand the risks, it is also important that they recognize the heightened safety of today’s pipelines because of modern construction practices. Recent construction activities have led to increased focus on the nature of Horizontal Directional Drilling (HDD) and inadvertent returns, which has also caused unnecessary start-and-stop construction activity. It is important that the public understand the risks created by this start-and-stop approach.
To understand how halting construction drilling can complicate the likelihood of success, it is necessary to look at the process itself. The Mariner East II Pipeline, which runs straight through Cumberland County, employs horizontal directional drilling (HDD) to minimize undue harm to the environment and existing structures. This is a technique of installing pipe and materials by drilling under existing structure instead of cutting through them with an open-cut, trench. The method is widely considered an industry best-practice, specifically for protecting the integrity of sensitive geographies, like aquifers and high water tables.
Similar to drilling a well, horizontal directional drilling allows builders to bore down and around natural obstacles, like bodies of water or shallow land features. During operation, drilling mud is flushed along the bore hole to remove drilled spoil, reinforce the walls of the drill path, and lubricate and cool the bit of the drill. The mud is a mixture of water and non-toxic bentonite clay, a natural element that poses no serious long-term environmental hazards (many consumer products contain bentonite, including cosmetics).
It is not unusual for the drilling fluid to escape during operations and disperse underground following a path of cracks and fissures in the soil, which has been seen locally. This occurrence, known as “inadvertent return,” is not uncommon. In fact, most builders and regulators alike anticipate and account for fluid migration during drilling, and it is not always required that drillers report these occurrences. The environmental impact is usually benign.
When considering pipeline construction and operations, policymakers are smart to make environmental impacts a priority. And they have. An agreement brokered by the state’s Department of Environmental Protection deserves a great deal of credit for establishing expanded oversight protocols that go beyond requirements. And, wisely, these deliberations brought together a broad range of stakeholders to ensure consensus around the precautionary actions.
Nevertheless, Mariner East 2’s example demonstrates just how precarious and uncertain the regulatory process remains for pipeline builders. Inadvertent returns have been blown out of proportion, which has pressured regulators to halt drilling to revise drilling plans. Once plans are approved, HDDs are allowed to resume. That approach works well in a vacuum, but it ignores the environmental risk of idling a drill underground. It is difficult to speculate what the worst case scenario could be, but the start-and-stop approach could risk increased harm via collapse of the borehole. At the end of the day, the environmental risk could be even greater than simply using an open-cut approach.
Ultimately, HDDs remain the industry standard for protecting environmental resources. A pipeline company should not be overly punished because it sought to employ a more environmentally friendly approach to building a pipeline project, but this could be the case with Mariner East 2.
Pennsylvania has experienced great success through Shale development, and there is no reason to back off now. The Keystone State is the second largest producer of natural gas — a title it’s held now for over four years — and the third in total energy production. And Pennsylvania has realized only a fraction of its potential. By continuing to invest in infrastructure, policymakers will create greater access to affordable, clean fuels and drive job creation. And, importantly, they will better protect our communities.
Absolutely, Pennsylvanians should be talking about pipeline safety. But those discussions should not be dictated by exaggeration or subject to knee-jerk reaction. Instead, let’s do things by the book: Write the rules and stick to them. Quit moving the goalposts on the Commonwealth’s energy producers.
Bill Godsey is owner and president of Geo Logic Environmental Services and a former geologist for the Texas Railroad Commission.