Renewables company could transform how millions of tons of hog waste are managed in NC

Published April 7, 2022

By Lisa Sorg

Outside a large steel barn in Magnolia, Martin Redeker scooped loads of dried hog waste, composted with carbon, onto a snow shovel for anyone to take a deep whiff. 

It smelled. 

Not of acrid ammonia or sulfur, but faintly like dirt.

For the past five years at a test site in Duplin County, Redeker and his business partner, Joe Carroll of Montauk Ag Renewables, have been tinkering with a new technology to process the millions of tons of hog waste produced each year in North Carolina. 

Redeker, an engineer, designed a system that is radically different from conventional anaerobic digesters, whose state draft permits are up for public comment. Instead, if this technology meets expectations, it could change how farmers use their lagoon and spray fields, and possibly negate the need for that antiquated method at all.

“We’re running out of room in our lagoons,” said one long-time farmer at a public meeting in Turkey, North Carolina, earlier this year. “We’re running out of spray fields.”

While the technology is not an environmental cure-all – it still produces biogas – it still could benefit residents, most of them people of color, who have long endured the odors and drinking water concerns associated with industrialized hog operations in eastern North Carolina.

Roy Lee Lindsey, CEO of the NC Pork Council, told Policy Watch in an email statement that “We’ve heard some talk about Montauk Renewables but are not familiar with the details of its technology. We look forward to learning more about the company and the ways it might benefit North Carolina’s pig farmers.

“North Carolina pig farmers are always looking for ways to continuously improve how we raise animals. Whether that involves using less water and energy or better manure management, we recognize the value of incremental steps forward.”

Whether Redeker’s and Carroll’s invention offers change that is incremental or transformational remains to be seen. Yet it relies on a simple principle of physics that has existed since the Big Bang: “Energy can’t be created or destroyed,” Redeker said.

Left to right: Martin Redeker and Joe Carroll of Montauk Ag Renewables; Max Pope, mayor of Turkey, at a public meeting earlier this year. (Photo: Lisa Sorg)

D own a long driveway off Blind Bridge Road in Magnolia, sits the barn with a shipping container affixed to its side. Inside the container is a makeshift office, outfitted with a couple of long tables and a whiteboard scribbled with numbers and flow charts.

Redeker, vice president of Montauk Ag Renewables, originally worked on technologies extracting oil from plastics in landfills. He splits his time between Colorado and North Carolina. Carroll, the company president, lives in Greensboro and previously worked in environmental mitigation, restoring streambanks and waterways. The two men owned a separate company that Montauk Renewables, a publicly traded company, purchased last year.

Inside the barn winds a network of conveyors and ovens, pipes and vacuum pumps. There is no stack, Redeker said, because there are no air emissions. 

The process would work like this: Montauk would send a truck to the farms, which either would slurp or excavate the waste directly from the lagoons; it’s also possible to intercept the waste before it reaches those pits. The truck would transport the waste back to the new Montauk facility off Highway 24 in Turkey, in Sampson County. There, the waste would be processed in a “closed-loop” system, and converted into biochar, which is essentially fertilizer; bio-oil, a substitute for petroleum; and biogas. 

As planned, the plant could process 12 tons per day, with the potential to expand to 20 tons. 

“This isn’t something that we just drew up on the back of a napkin,” Carroll told attendees of the public meeting in Turkey. “There’s a lot of engineering, a lot of iron, a lot of steel that goes into this.”

To wring as much as energy from the waste, it must be dried and processed within seven to 10 days. “That’s when a lot of the material starts to degrade and you start to get a lot of that odor,” Redeker said. “We’re in the business of taking advantage of all the energy we possibly can. We’re not stockpiling the waste.”

The public meeting in Turkey was prompted by the news that Montauk Ag Renewables had purchased a former Bay Valley Foods warehouse on the west side of Turkey for $5.5 million. Montauk chose the warehouse in part because it is near five hog lagoons holding about 150,000 tons of waste.

About 50 people – equivalent to about 20% of Turkey’s population – crammed into the small town hall to hear from Redeker and Carroll, who were invited at the mayor’s behest.

Town residents said they were worried about potential odors and flies – the very issues plaguing neighbors of the farms themselves.

“I don’t believe we’re bringing in an odor problem,” Redeker said. “And the farms are going to smell less and less as we remove the waste.”

Residents were also concerned about being sandwiched between two biogas facilities. On the east side of town, Align RNG is a joint project between Smithfield Foods and Dominion Energy. It is a hub for a conventional biogas system. Farmers install covers on their waste lagoons to capture methane, which is then funneled through a miles of underground pipelines to Align RNG. 

Align RNG cleans and upgrades the biogas and sends it through a pipeline for Duke Energy to use in its natural gas plants. 

Montauk Ag Renewables, whose property is outlined in blue, has purchased a former food warehouse on the west side of Turkey, in Sampson County. A separate project, Align RNG, headed by Dominion Energy and Smithfield Foods, operates on the east side of town off Highway 24 and BF Grady Road. (Base map: Sampson County GIS)

A pipeline runs along Highway 24, which could be an injection point for Montauk’s biogas, Carroll said. However, pipeline companies usually partner with a single user for injection points, “so we will most likely not be partnering with Align.” If Montauk can’t inject into the pipeline, it plans to contract with a trucking company to deliver the gas to another injection point.

Jim Monroe, spokesman for Smithfield Foods, said via email that while the company isn’t “closely familiar with this project and can’t speculate on the outcome of testing, we’re generally supportive of technologies that help farmers manage manure and have the potential to enhance the systems we have in place today. Within our own operations, we’re continually looking for ways to innovate and improve upon available technologies to further support farmers and agriculture and steward the environment.”

However, conventional biogas systems like those deployed by Align RNG have shortcomings. Conventional anaerobic digesters are expensive – hundreds of thousands of dollars or more – a cost borne by the farmers.

Montauk’s technology, Carroll said, requires no upgrades at the farm. “We work with existing infrastructure. They won’t need to retrofit their farm.”

Conventional digesters still leave at least one lagoon uncovered, the main source of the objectionable odors. “High freeboard” – industry parlance for a lagoon that is too full – is a common violation at these farms, according to state records.

The Rev. Jimmy Melvin, center, is pastor of Mt. Zion AME Zion Church in Sampson County. The church had to dig a new well after the county board of health found elevated levels of nitrates in the drinking water. The church is near several hog farms. Melvin attended a public meeting in Turkey about Montauk Ag Renewables proposal to convert hog waste for beneficial reuse. (Photo: Lisa Sorg)

The feces and urine are pumped from the lagoons and sprayed on adjacent fields. That waste then seeps into the groundwater, which can contaminate streams and drinking water wells.

A recent study by three scientists at UNC Wilmington shows that industrialized swine farms, and their lagoon/sprayfield systems, are a source of chronic “nitrogen, phosphorus and fecal microbial” contamination in the soil and waterways in eastern North Carolina.

Nitrogen and phosphorus in waterways can stimulate the growth of toxic algae; fecal contamination poses a public health risk.

Preliminary sampling data shows that nine sites in the Lower Cape Fear River Basin recorded increases in fecal bacteria. Thirteen sampling stations showed significant upticks in nitrate levels. Some drinking water wells in eastern North Carolina have elevated nitrate levels. The Rev. Jimmy Melvin, pastor of Mt. Zion AME Zion Church in Magnolia, attended the meeting in Turkey. He had to have a new well drilled for the church after the local health department notified him nitrate levels in the drinking water were unsafe.

At their test facility in Magnolia, Redeker and Carroll grow switchgrass. If harvested at the right time, switchgrass can clean the soil of excess nitrogen and phosphorus because the plant has absorbed those elements into its stalk.

When the plant in Turkey is fully built out, each of the 20 units will processes 12 to 15 tons of waste per day, essentially removing 275 tons of waste from the watershed daily.

“That’s what got me interested in this in the first place,” Carroll said. “It wasn’t the energy piece, it was reducing the nitrogen and phosphorus in this watershed.” 

Since Smithfield and Dominion announced the Align RNG project, many eastern North Carolina residents and climate activists have objected to it because the release of any methane-producing gas escalates climate change. And eastern North Carolina often bears the brunt of those effects, as hurricanes, storms and floods intensify.

Injecting biogas into traditional pipelines only entrenches the reliance on fossil fuels, they say.

But the methane already exists, Carroll said, generated by the hog, spray field and the lagoon. “We’re able to capture that methane and get a beneficial reuse,” he said, “rather than releasing it into the atmosphere.”

Montauk Renewables, based in Pittsburgh, has long captured landfill gas for energy projects. It recently took over a dairy operation in Idaho to convert the waste into biogas.

“We harvest the gas,” said John Ciroli, vice president general counsel of Montauk. “We’re not making it.”

At the meeting in Turkey, jars of dried hog waste, switchgrass carbon, bio-oil and compost were lined up in a row. Redeker invited attendees to open them. Some smelled like nothing. The switchgrass smelled like tea. The manure smelled like dirt.