By Jared Strong
An eastern Iowa company that says it benefits the environment by turning agricultural byproducts into energy was recently fined for burying barrels of waste from the operation in a giant pit, according to the Iowa Department of Natural Resources.
In June 2022 the DNR investigated a complaint that numerous large drums of potentially hazardous material had been buried at a site southeast of New Liberty, where Sievers Family Farms has a cattle operation and jointly operates AgriReNew.
AgriReNew uses animal manure and byproducts from soybean oil and ethanol plants, among others, to create methane, according to a video posted to its Facebook page. The methane — which is often marketed as a renewable biogas — is burned to produce electricity that is sold to a utility and to create heat for the cattle operation.
The DNR investigated the property and noted about 100 metal and plastic drums in a storage area, many of which contained engine coolant. Bryan Sievers, manager of AgriReNew, told the DNR that he planned to recycle or properly dispose of those containers.
“At this meeting, Mr. Sievers stated that he was not aware of any drums buried on the property,” according to a recent DNR administrative order.
At the time, workers were digging a large basin on the site to build another anaerobic digester to produce biogas. That project was part of a separate partnership with Missouri-based Roeslein Alternative Energy, which was awarded an $80 million federal “climate smart” grant to, in part, produce renewable natural gas, according to a company press release last year.
Jacob Forgie, a DNR environmental specialist who investigated the barrel complaint, saw no evidence of buried waste at the site or in the work area and concluded that the complaint was unfounded.
However, several weeks later Roeslein did some “exploratory digging” based on information from an AgriReNew employee and found a couple of plastic drums buried about three feet deep in a nearby area, the DNR order said. Sievers said he had questioned his employees about the potential burial and reported the find to the DNR.
A subsequent excavation of the site found at least 20 drums — each with a capacity of about 55 gallons — that contained foamy, rancid-smelling and brownish-black fluids, the order said. They were buried in a pit that was about 20 feet wide, 40 feet long and 14 feet deep.
Sievers said a former employee had been instructed to empty barrels that contained food waste for the digesters, crush them and recycle them, but: “He apparently did it for many of the barrels, but not all of them.”
He said the employee — for reasons he doesn’t know — buried some of the barrels while Sievers was away for a family vacation in 2021. Sievers couldn’t say whether it is faster to dispose of the barrels by emptying and crushing them or by digging a large pit and burying them.
Tests of the contaminated soil found small concentrations of barium, chromium and lead that were well below state limits. Water from a nearby private well also had barium, in a concentration of about one-twentieth of what is considered safe to drink by federal regulators.
Sievers said the barrels contained food waste and that the contaminants naturally occur in the soil. The DNR was unable to verify what the barrels contained because it deemed the pit “unsafe to occupy” and didn’t collect samples of the liquids, the order said.
Forgie said a significant amount of contaminated soil was taken to a landfill. The pit was refilled with sand and topsoil that hadn’t been contaminated.
AgriReNew recently agreed to pay a $5,000 fine for the incident.
Editor’s note: This article was updated with information from Bryan Sievers.