US Army Corps of Engineers’ $1.3 billion dredging of North Carolina river could release ‘forever chemicals’

Taking a blood sample from a wild American alligator is not a clinical procedure. North Carolina native Kemp Burdette describes the process as an all-hands-on-deck situation. After rolling over the alligator in a boat and throwing a hook and lead weight attached to heavy-gauge fishing line over the beast’s back, you spin until the hook catches and flips the creature. Next comes the all-hands game. Ideally, a small group of people team up to hold the animal down – it will relax, but just watch the tail – drape its eyes with a towel, tape its mouth shut and poke between the thick armor with a needle.

“Alligator jaws have incredible crushing force, but not many pounds of opening force,” says Burdette. “You can actually shut the mouth of an alligator, even a big one.”

Burdette knows this because the Cape Fear River falls under his jurisdiction. A former Navy search and rescue swimmer who grew up swimming around swamps and backwaters, he is Riverkeeper, the local leader of the national environmental organization Waterkeeper dedicated to saving the region’s 200-mile river ecosystem.

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He fights against these large predators not for sport but to chase away a microscopic threat: PFAS, or per- and polyfluoroalkyl substances. Burdette worked with a team of scientists from North Carolina State University who measured the concentration of PFAS in the blood of alligators and found that it correlated with immune problems in the animals — another worrying sign in a decades-long history of PFAS poisoning on Cape Fear.

First brought to the public eye by investigative articles in the local newspaper in Wilmington, North Carolina. StarNews In 2017, GenX, a PFAS substance used to produce Teflon coating, also known as hexafluoropropylene oxide dimer acid, saturated the region’s watershed and drinking water for years. This has made the region a hotbed of investigation, research and regulatory efforts around hazardous chemicals “forever.”

But a federal megaproject could create even more problems. The U.S. Army Corps of Engineers has proposed a $1.3 billion plan to widen the Cape Fear River, using a fleet of boats, barges and construction equipment to dig up 35 million cubic yards of dirt and sand. About half of these materials would be placed on nearby beaches and habitat restoration sites; the rest would be transported offshore for disposal. The excavations would deepen the harbor by 42 to 47 feet and, in some places, extend the width of the river to the length of two football fields.

It is a colossal logistics gamble intended to accommodate ever-larger post-Panamax ships – whose size matches the dimensions of the recently expanded Panama Canal, widened in 2016 – and keep the local shipping industry competitive in a global supply chain obsessed with efficiency. In estuaries like the Cape Fear, deepening a channel can allow tides and storm surges to travel further upstream, carrying salt water with them. That’s one reason opponents argue the project could disrupt contaminated sediments and amplify flooding as sea levels rise — changes they say could worsen the region’s significant PFAS problem.

After months of growing community concern, the plan was temporarily suspended in January. And on February 24, the confrontation intensified: The North Carolina Department of Environmental Quality formally objected to the Corps’ proposed environmental impact statement (EIS), saying in a statement press release that the proposal did not provide “sufficient information on PFAS, flooding, and placement of dredged materials.” The Corps and the North Carolina State Port Authority said in written statements that they were deciding what next steps to take. The Corps could still reach an agreement through a mediation process with state environmental officials, according to Jedidiah Cayton, Corps public affairs specialist.

“If the Army Corps of Engineers can make changes to its proposal to protect people’s health and the environment, we are at the table to continue this conversation,” DEQ Secretary Reid Wilson said in a statement. statement.

The state Port Authority argued the project was existentially necessary to keep the Port of Wilmington competitive in an era of bigger ships, heavier loads and deeper ports. The nearby ports of Charleston, South Carolina, and Savannah, Georgia, have already been dredged to depths of 52 and 47 feet, respectively. Without a deeper canal, shippers using modern post-Panamax vessels must pack lighter loads or reroute goods by road to reach Wilmington — costly propositions that threaten a port that contributes $14.8 billion a year to North Carolina’s economy.

But local communities are resisting. Some municipalities across the state, including Wilmington, Bald Head Island, Southport and Leland, have passed resolutions requiring stricter mitigation measures. The Cape Fear River supplies drinking water to more than 500,000 inhabitants, but contamination due to the expansion project would disproportionately harm people from low-income and minority populations. People in these groups are more likely to depend on subsistence fishing of the river for proteins– and less likely to be able to afford the expensive reverse osmosis filtration systems that remove PFAS.

An Army Corps of Engineers spokesperson said Scientific American that because the review is ongoing, the agency would have no further comment on the current plan. The Body’s own calculation The draft report states that the dredging operation would allow larger vessels to enter the widened canal fully loaded, bringing an overall annual economic benefit to the region’s economy of nearly $16 million. However, the benefit/cost ratio is relatively low, at 1.3:1.

The Corps has flatly refused to test sediment for PFAS, worrying local scientists and environmentalists like Burdette. The discovery of Cape Fear’s flanks will not only disrupt ecosystems, but will likely also cause salt water intrusion further upstream. Burdette fears that the phenomenon of “ghost forests” — clusters of native bald cypress trees weakened, distorted and ruined by salinity — could seep into the island of his childhood.

And this is where the danger of PFAS could become more pronounced. When a PFAS is trapped in sediment, it binds to organic matter sequestered in the murky depths. But as salinity increases, the risk of PFAS reverting to the dissolved phase increases. It becomes an “exposure agent,” says Ralph Mead, professor of earth and ocean sciences at the University of North Carolina Wilmington and head of the North Carolina PFAS Research Network.

Mead cautions that while this salinity-driven change has been proven in some of the thousands of PFAS chemicals, it remains a hypothesis for some of the perennial chemicals found in Cape Fear, such as GenX. To his knowledge, there has never been a comprehensive, systematic study examining the before and after impact of dredging on PFAS exposure.

This risk keeps Kerri Allen, coastal management program director at the North Carolina Coastal Federation, up at night. His organization opposed several aspects of the dredging project: its impacts on water quality, local wildlife and shoreline erosion. But the concerns raised here about PFAS have been “a unifying factor” in advocacy and resistance.

Science supports a major concern about the combination of saltwater intrusion, sediment and PFAS chemical seepage. A study of historical tide records from the 19th century to today, found that the tidal range around Wilmington, or the difference in height between high tide and low tide, had already doubled over the past 130 years. “We’re just in the purgatory of knowing the risk but not being able to do anything about it,” Allen said. Scientific American before the DCM rejected the initial proposal. She is now encouraged that the state is taking PFAS concerns seriously.

“The science clearly shows that PFAS are present in Cape Fear River sediments, and dredging has the potential to mobilize this contamination,” Allen says. “Even when the Corps suggests there is little that can be done, it is important that DCM pushes for a more thorough assessment of these risks. »

What’s happening on the Cape Fear is a preview of a much larger regulatory blind spot in the Corps’ national mission and the broader maritime economy. Corps dredges about 240 million cubic yards of material each year, according to Doug Garman, the agency’s public affairs manager, with an annual dredging budget of $1.8 billion. While scientists work to better understand the interaction of PFAS, salinity, and sediment, the Corps makes no effort to consider the risk of these chemicals in its key mission of maintaining approximately 12,000 miles of inland and intracoastal waterways, 13,000 miles of coastal waterways, and 400 ports, harbors, and turning basins.

“There are compounds that never decompose,” says Burdette. “PFAS is a big problem, and this area has been contaminated for over 50 years. You should really do a lot of modeling and sampling.”

The Corps first proposed the Cape Fear expansion in 2020, after a feasibility study by the state Port Authority and a few years after PFAS risks in the area made headlines. The expansion is part of a national effort to expand ports to accommodate the latest generation of post-Panamax oversized container ships.

As such, this is one of several massive dredging projects underway by the Corps. According to William Doyle, CEO of industry group Dredging Contractors of America, the United States spent $2.4 billion on dredging in 2024, with billions of dollars in future projects beginning in Alabama, Texas, New York, Georgia and Maryland. Between the need to expand and maintain commercial ports and the imperative to replenish beaches that boost local tourism economies, dirt and sand transportation has become a big climate-driven industry.

“God doesn’t build the earth anymore,” Doyle said. “There are only two ways to get to dry land: one through a volcanic eruption and the other by extracting dredged material from the ocean floor.”

Doyle argues that riverbed reclamation is not as chaotic as its opponents suggest. Ship teams – cutter dredgers that direct underwater drillsclamshell dredges that dump a bivalve bucket onto the shore, and pump dredges that suck up sediment from the riverbed operate in relatively rapid succession. For the Cape Fear project, much of the sediment will be repositioned on estuaries, islands and beaches; if it does indeed contain a PFAS risk, it will spread into human and animal habitats.

Doyle says the industry has been constrained by increased environmental regulations that require mitigation, testing and restrictions limiting work to certain hours and areas. But these regulations, by and large, do not include testing or even consideration of PFAS.

Starting in 2020, the Michigan Department of Environment, Great Lakes and Energy (EGLE) became one of the first regulatory agencies in the country to require dredging operations to test for PFAS. After the state adopted its PFAS Drinking Water Rules In August 2020, EGLE decided to require PFAS sediment testing for dredging projects to ensure that spoil from this work does not contaminate the drinking water supply. An EGLE representative says that of the state’s 69 ports maintained by the Corps, 14 have been impacted by known sources of PFAS.

The mic The higan testing mandate became controversial earlier this year when it was cited as an obstacle to plans to dredge the city of Grand Haven’s harbor; industry members balked and the state’s congressional delegation even pressured EGLE to postpone the “port killings“. Ultimately, dredging continued, but it was based on a compromise: the project would be divided into sections, with two highest priority areas that already had the green light for valid sediment testing.

The lack of testing in North Carolina is a direct reflection of the limited state of national regulations. Federal PFAS rules cover only a handful of the 15,000 known PFAS chemicals, and the Trump administration has sought to undo the regulations the federal government has imposed on them— abandoning four regulations entirely and pushing back implementation of the remaining two regulations from 2029 to 2031. Trump’s EPA also proposed Cancel an expansion of the Toxic Substances Control Act in the Biden era that would have significantly improved awareness of PFAS risk. There is one way to hold polluters accountable for harm from PFAS and potential harm from dredging: the EPA’s rule designating PFOA and PFOS as hazardous substances under CERCLA, the Superfund sites law. But by then, the damage will be done.

Environmental advocates in North Carolina argue that testing should be a fundamental prerequisite for any work on the Cape Fear river system because of the region’s history with PFAS. For decades, the manufacturing site of Chemours in Fayetteville, a DuPont spin-off, has been dumping GenX into the river. At a conference last year, Emily Donovan, an activist with the community action group Clean Cape Fear, proclaimed that downstream, “churches in Brunswick County are baptizing their babies in PFAS-contaminated tap water.” Although Burdette and others have worked to reveal the extent of PFAS pollution and a consent agreement was put in place in 2019 to reduce Chemours’ spills, the company has been cited for violation of consent order in 2021, and is actively seeking to expand production in its factory.

“The Cape Fear River has a long and storied history of horrific abuse and mistreatment,” Allen said. “In almost every situation where we have sampled, there have been high concentrations of PFAS.”

Proponents of dredging say no testing has been done on the sediment and therefore there is no evidence that it contains high concentrations of PFAS. Allen believes this point has been “weaponized” to some extent. Maybe the levels aren’t so bad. But it’s a good question worth exploring. There is a feeling in the region that the risks are real; the local water department recently installed a $46 million carbon filtration system to purify the area’s drinking water. Meanwhile, the Corps didn’t even mention PFAS in its entire initial draft EIS.

The complex interaction of tides, sediments, shorelines and salinity is, by its nature, an extremely fluid situation. Currently, a team of local researchers in North Carolina is collaborating to better understand how dredging can lead to the formation of more ghost forests and salinity, with the goal of assessing how much saltwater is entering the river system and how much saltwater is needed to impact local ecosystems. Various approaches are integrated to obtain a more detailed understanding: measuring the history of foraminifera, a single-celled marine organism, in sediments to assess tidal movements; hollowing out bald cypress trees and measuring the width of the rings to see when salt water slowed their growth; and installing a series of sensors to obtain hour-by-hour measurements of tidal activity to better predict how storms and extreme weather can alter tree health. Researchers recently published a study that found that dredging could accelerate the formation of ghost forests.

“It’s really amazing to see what these salinity signatures actually look like on a daily, monthly, and annual time scale, because it’s not like salinity is increasing slowly and uniformly,” says Phil Bresnahan, an oceanographer at UNC Wilmington and one of the study’s co-authors. “There are these big questions about frequency, duration, intensity, severity, for example, what is the combination of these factors in salinity that then impacts the ecology?”

Studies like this, along with sediment analyses, could provide a better understanding of what unleashing massive dredging machines on the river system can do. Mead estimates that a comprehensive before-and-after study of dredging and PFAS would take a year, although mimicking actual dredging could prove difficult. Michigan EGLE scientists found that testing sediment for PFAS (by taking a core sample, drying it, and running it through a mass spectrometer) cost about $335 per sample. At the standard rate of one test per 10,000 cubic yards of material, testing would cost the Cape Fear project about $1.2 million, or less than 0.1 percent of its total budget.

Since there is no viable way to clean up PFAS-containing sediments (they can only be contained), opponents face a strategic problem: They are fighting an irreversible infrastructure project without the definitive data needed to prove its consequences. Bresnahan calls this the ecosystem ratchet effect; Once something is set in motion, it’s very, very difficult to go back.

But there is still some reluctance. If the Corps and the state Port Authority succeed in getting the project approved, it still must be funded; North Carolina’s government may be able to be convinced by voters not to provide the state with the required 25 percent share of the budget, or about $339 million.

Large government infrastructure projects carry immense momentum and are notoriously difficult to stop. But the state’s recent rejection of the original plan has changed the dynamic, and Burdette continues to push for data.

Burdette, who grew up swimming and drinking Cape Fear water, is highly exposed himself; his blood tested positive for significant concentration levels of PFAS. Her father died a few years ago from kidney cancer, a type of cancer closely linked to PFAS exposure. Despite her vegan diet, Burdette has extremely high cholesterol, another known side effect of exposure to these everlasting chemicals; he regularly does blood tests and kidney scans. Like the banks of the river he protects, Burdette carries the chemicals with him, waiting for more data and more answers.

“I try to prepare for whatever eventuality the doctor finds,” he says.