DAPL’s Dangerous Leak Detection System

Woefully inadequate leak detection jeopardizes water and families
Date: 07/17/2020

DAPL is dangerous and should be shut off.


Every day over the last three years, the Dakota Access pipeline has pumped over half a million barrels of Bakken crude under Lake Oahe in North Dakota — the sole source of drinking water for the people of the Standing Rock Sioux Tribe. All the while, it has operated with one of most criminally inadequate leak detection systems of any pipeline in America.

Thankfully, recent developments coming out of the Washington D.C. court circuits have heralded a significant victory for the Standing Rock movement. Federal Judge James E. Boasberg, after vacating DAPL’s permit earlier this year over inadequate environmental review, has ordered for the pipeline to be shut down and emptied of its oil. This followed similar victories in a ruling against the proposed Keystone XL pipeline and the cancellation of the Atlantic Coast pipeline.

In response to the ruling, a spokeswoman for parent company Energy Transfer (ET) stated in an email that the company would not be shutting down the line, clarifying later that they’d be seeking relief through the court system. That temporary relief came down earlier this week, when a Court of Appeals froze Boasberg’s order. While this allows DAPL to stay online for longer, the verdict maintains the authority to halt operations at any time.

With the legal drama still unfurling, one thing is clear: DAPL failed to meet basic environmental standards, and thus, it should be shut down immediately.

DAPL’s potential hazard has not lessened over time. Dakota Access was and is still one of the riskiest freshwater crossings by any pipeline in the world, a fact which ET and the Army Corps of Engineers obfuscated and downplayed as much as possible in the approval process. Adding to the concern, if DAPL does remain open, its oil load is scheduled to double soon, due to a North Dakota Public Service Commission ruling approving new pumping capability.

We commend Boasberg’s decision to hold DAPL to account for its faulty environmental review process. Oil projects, even ones that contribute to large corporate profits, shouldn’t be above environmental laws in this country. That’s why Lakota People’s Law Project attorneys filed an amicus (“friend of the court”) brief elucidating that argument in support of Standing Rock’s attorneys at Earthjustice. You can read that here.

As the DAPL saga continues, now four years after the start of the Standing Rock movement, it remains pertinent to understand just how deeply disastrous this project is.

A Faulty System

The Dakota Access pipeline is an unsafe piece of infrastructure. To begin with, DAPL’s bore defies global and national standards for pipeline safety. The 30-inch steel pipeline has been placed 92 to115 feet below Lake Oahe, near the Standing Rock reservation boundary. The pipe was routed under the lake using a technique called Horizontal Directional Drilling (HDD), which involves drilling a series of boreholes of increasing diameter while propping open the borehole and then threading pipe through the tunnel that is created. According to an independent assessment, this is one of the longest HDD projects in the world and violates the standard practice of limiting HDD to under a mile (5,280 ft).

There are few, if any, crude oil pipelines in the world that have such a long HDD component, especially under such a sensitive freshwater crossing used for drinking water and agriculture. Worse, in the permitting process, ET chose to reroute the pipeline adjacent to Lakota land, away from its original trajectory nearer the largely-white areas of Bismarck and Mandan. It also chose to throw out industry standards to create one of the riskiest pipeline water crossings in the world. That is textbook environmental racism.

Because DAPL is located near two natural gas pipelines that cross under Lake Oahe at a shallower depth, proponents of the pipeline (i.e. “DAPL Facts”) attempt to dismiss concerns about DAPL’s environmental impact, arguing there’s nothing uniquely threatening about Dakota Access. However, since crude oil is more toxic and persistent than natural gas, a leak in DAPL would be much more environmentally damaging than a leak from one or both of the natural gas pipelines.

“Nobody has really dug into this issue of a pipeline going under such a huge body of freshwater in an important reservoir that is a drinking water source for a lot of Americans, so I started to investigate everything they had planned to do,” said Steve Martin, energy infrastructure expert and enrollee of the Chippewa nation. “There is no leak detection system in the most critical part of the pipeline [Lake Oahe].”

Although Dakota Access has conspicuously not released any details on DAPL’s leak detection system (LDS), an independent pipeline consulting company, ENVY Enerji ve Çevre Yatırımları A.Ş., performed an assessment of DAPL’s environmental impact and found that DAPL’s LDS may be unable to detect leaks of up to 1-2 percent of its total capacity per day (up to 11,400 bbl/day or 480,000 gal/day). If such a leak were to occur under Lake Oahe, it would be undetectable until the oil migrated to the lake surface and was spotted by an observer. If a leak occurred during the 3-4 months per year when the lake is covered in several inches of ice, it may go undetected until the ice melts.


To put it bluntly: DAPL is unable to detect 75 percent of potential leaks. A leak detection system that can only detect leaks a quarter of the time creates huge vulnerabilities, especially given the high risk it poses to the Standing Rock Sioux Tribe. Surface expressions should not be the main way leaks get detected, particularly in areas like the Lake Oahe crossing, where leaks may not migrate to the surface for days, weeks, or even months.

And if it leaks?

A leak under Lake Oahe could be unfixable. The lake crossing is more than a mile long, nearly 100 feet under the bottom of the lakebed. A leak there would mean construction teams would have to drain the pipeline, pull it out from the ground, redrill the borehole, and push a new section of pipeline through.

Moreover, it could potentially spell ruin for the people living downstream.

Should a leak occur under the lake, containment and remediation efforts would be greatly hampered by the depth of the pipeline underground and its location under the lake. When discussing a worst case discharge scenario, the Army Corps stated that routing the pipeline roughly 100 feet under the lake would have a “greater response time” and would result in “high consequences.”

Despite the extreme challenges posed by the physical location of the pipeline, the Army Corps does not provide any plan in the existing assessment to contain an underground leak or clean contaminated soil and groundwater under Lake Oahe, placing a burden on the Tribe to do so. Additionally, ET stock prices have been steadily dropping for the past four years, meaning the company may not be in a solid enough financial position to pay for a major cleanup project and would likely pass those costs onto local landowners and federal taxpayers.

Additionally, the Army Cops failed to account for the multi-directional flow of groundwater back and forth between Lake Oahe and its underlying aquifers. Because the lake feeds the aquifer when water levels are high and is fed by the aquifer when water levels are low, an oil spill could either be confined to the lake or pulled downward to contaminate connected aquifers. This situation creates the possibility of a slow leak (less than 2 percent of the pipeline’s daily flow rate) remaining undetectable as it contaminates groundwater throughout the wet season when water is high, only for that reservoir of contaminated groundwater to flow back up into the lake during the dry season.

If this happens, it could literally poison the Native communities living nearby for years to come.

Crude oil like that being pumped through DAPL is a mixture of thousands of organic chemicals. This includes a large number of carcinogenic or otherwise toxic chemicals, notably benzene and its derivatives, and a class of compounds known as polycyclic aromatic hydrocarbons (PAHs). These chemicals, particularly PAHs, can bioaccumulate in plankton and make their way up the food chain to harm fish, birds, and humans.

There are at least nine threatened or endangered species within the DAPL project area, including the pallid sturgeon, the grey wolf, and the whooping crane, all of which may be directly or indirectly affected by a spill. The accumulation of toxic substances in fish is particularly relevant for Standing Rock Sioux tribal members, some of whom rely on fish from Lake Oahe for subsistence. A spill would cut off members of the Tribe from both their primary source of drinking water and a ready source of high-quality protein they have utilized for thousands of years.

Moving Forward

DAPL should have never been built to begin with. Its environmental review was just as flawed as its inadequate leak detection. It threatens the life and livelihoods of the Standing Rock Sioux Tribe and all the people downriver. Oil flow should be shut off immediately.

As we await further news from the D.C. courts, we hope that these dispatches from the NoDAPL trial archives help to dispel myths about the so-called safety of oil pipelines.

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